Xuan Zhuo
2023-Mar-30 01:50 UTC
[PATCH v6] virtio: add VIRTIO_F_NOTIFICATION_DATA feature support
On Thu, 30 Mar 2023 01:49:23 +0300, Viktor Prutyanov <viktor at daynix.com> wrote:> On Fri, Mar 24, 2023 at 10:50?PM Viktor Prutyanov <viktor at daynix.com> wrote: > > > > According to VirtIO spec v1.2, VIRTIO_F_NOTIFICATION_DATA feature > > indicates that the driver passes extra data along with the queue > > notifications. > > > > In a split queue case, the extra data is 16-bit available index. In a > > packed queue case, the extra data is 1-bit wrap counter and 15-bit > > available index. > > > > Add support for this feature for MMIO, channel I/O and modern PCI > > transports. > > > > Signed-off-by: Viktor Prutyanov <viktor at daynix.com> > > Acked-by: Jason Wang <jasowang at redhat.com> > > Reviewed-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com> > > --- > > v6: use VRING_PACKED_EVENT_F_WRAP_CTR > > v5: replace ternary operator with if-else > > v4: remove VP_NOTIFY macro and legacy PCI support, add > > virtio_ccw_kvm_notify_with_data to virtio_ccw > > v3: support feature in virtio_ccw, remove VM_NOTIFY, use avail_idx_shadow, > > remove byte swap, rename to vring_notification_data > > v2: reject the feature in virtio_ccw, replace __le32 with u32 > > > > Tested with disabled VIRTIO_F_NOTIFICATION_DATA on qemu-system-s390x > > (virtio-blk-ccw), qemu-system-riscv64 (virtio-blk-device, > > virtio-rng-device), qemu-system-x86_64 (virtio-blk-pci, virtio-net-pci) > > to make sure nothing is broken. > > Tested with enabled VIRTIO_F_NOTIFICATION_DATA on 64-bit RISC-V Linux > > and my hardware implementation of virtio-rng with MMIO. > > > > drivers/s390/virtio/virtio_ccw.c | 22 +++++++++++++++++++--- > > drivers/virtio/virtio_mmio.c | 18 +++++++++++++++++- > > drivers/virtio/virtio_pci_modern.c | 17 ++++++++++++++++- > > drivers/virtio/virtio_ring.c | 19 +++++++++++++++++++ > > include/linux/virtio_ring.h | 2 ++ > > include/uapi/linux/virtio_config.h | 6 ++++++ > > 6 files changed, 79 insertions(+), 5 deletions(-) > > > > diff --git a/drivers/s390/virtio/virtio_ccw.c b/drivers/s390/virtio/virtio_ccw.c > > index 954fc31b4bc7..02922768b129 100644 > > --- a/drivers/s390/virtio/virtio_ccw.c > > +++ b/drivers/s390/virtio/virtio_ccw.c > > @@ -391,7 +391,7 @@ static void virtio_ccw_drop_indicator(struct virtio_ccw_device *vcdev, > > ccw_device_dma_free(vcdev->cdev, thinint_area, sizeof(*thinint_area)); > > } > > > > -static bool virtio_ccw_kvm_notify(struct virtqueue *vq) > > +static inline bool virtio_ccw_do_kvm_notify(struct virtqueue *vq, u32 data) > > { > > struct virtio_ccw_vq_info *info = vq->priv; > > struct virtio_ccw_device *vcdev; > > @@ -402,12 +402,22 @@ static bool virtio_ccw_kvm_notify(struct virtqueue *vq) > > BUILD_BUG_ON(sizeof(struct subchannel_id) != sizeof(unsigned int)); > > info->cookie = kvm_hypercall3(KVM_S390_VIRTIO_CCW_NOTIFY, > > *((unsigned int *)&schid), > > - vq->index, info->cookie); > > + data, info->cookie); > > if (info->cookie < 0) > > return false; > > return true; > > } > > > > +static bool virtio_ccw_kvm_notify(struct virtqueue *vq) > > +{ > > + return virtio_ccw_do_kvm_notify(vq, vq->index); > > +} > > + > > +static bool virtio_ccw_kvm_notify_with_data(struct virtqueue *vq) > > +{ > > + return virtio_ccw_do_kvm_notify(vq, vring_notification_data(vq)); > > +} > > + > > static int virtio_ccw_read_vq_conf(struct virtio_ccw_device *vcdev, > > struct ccw1 *ccw, int index) > > { > > @@ -495,6 +505,7 @@ static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev, > > struct ccw1 *ccw) > > { > > struct virtio_ccw_device *vcdev = to_vc_device(vdev); > > + bool (*notify)(struct virtqueue *vq); > > int err; > > struct virtqueue *vq = NULL; > > struct virtio_ccw_vq_info *info; > > @@ -502,6 +513,11 @@ static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev, > > unsigned long flags; > > bool may_reduce; > > > > + if (__virtio_test_bit(vdev, VIRTIO_F_NOTIFICATION_DATA)) > > + notify = virtio_ccw_kvm_notify_with_data; > > + else > > + notify = virtio_ccw_kvm_notify; > > + > > /* Allocate queue. */ > > info = kzalloc(sizeof(struct virtio_ccw_vq_info), GFP_KERNEL); > > if (!info) { > > @@ -524,7 +540,7 @@ static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev, > > may_reduce = vcdev->revision > 0; > > vq = vring_create_virtqueue(i, info->num, KVM_VIRTIO_CCW_RING_ALIGN, > > vdev, true, may_reduce, ctx, > > - virtio_ccw_kvm_notify, callback, name); > > + notify, callback, name); > > > > if (!vq) { > > /* For now, we fail if we can't get the requested size. */ > > diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c > > index 3ff746e3f24a..dd4424c14233 100644 > > --- a/drivers/virtio/virtio_mmio.c > > +++ b/drivers/virtio/virtio_mmio.c > > @@ -285,6 +285,16 @@ static bool vm_notify(struct virtqueue *vq) > > return true; > > } > > > > +static bool vm_notify_with_data(struct virtqueue *vq) > > +{ > > + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vq->vdev); > > + u32 data = vring_notification_data(vq); > > + > > + writel(data, vm_dev->base + VIRTIO_MMIO_QUEUE_NOTIFY); > > + > > + return true; > > +} > > + > > /* Notify all virtqueues on an interrupt. */ > > static irqreturn_t vm_interrupt(int irq, void *opaque) > > { > > @@ -363,12 +373,18 @@ static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned int in > > const char *name, bool ctx) > > { > > struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); > > + bool (*notify)(struct virtqueue *vq); > > struct virtio_mmio_vq_info *info; > > struct virtqueue *vq; > > unsigned long flags; > > unsigned int num; > > int err; > > > > + if (__virtio_test_bit(vdev, VIRTIO_F_NOTIFICATION_DATA)) > > + notify = vm_notify_with_data; > > + else > > + notify = vm_notify; > > + > > if (!name) > > return NULL; > > > > @@ -397,7 +413,7 @@ static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned int in > > > > /* Create the vring */ > > vq = vring_create_virtqueue(index, num, VIRTIO_MMIO_VRING_ALIGN, vdev, > > - true, true, ctx, vm_notify, callback, name); > > + true, true, ctx, notify, callback, name); > > if (!vq) { > > err = -ENOMEM; > > goto error_new_virtqueue; > > diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c > > index 9e496e288cfa..05deba5153bd 100644 > > --- a/drivers/virtio/virtio_pci_modern.c > > +++ b/drivers/virtio/virtio_pci_modern.c > > @@ -288,6 +288,15 @@ static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) > > return vp_modern_config_vector(&vp_dev->mdev, vector); > > } > > > > +static bool vp_notify_with_data(struct virtqueue *vq) > > +{ > > + u32 data = vring_notification_data(vq); > > + > > + iowrite32(data, (void __iomem *)vq->priv); > > + > > + return true; > > +} > > + > > static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev, > > struct virtio_pci_vq_info *info, > > unsigned int index, > > @@ -298,10 +307,16 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev, > > { > > > > struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > > + bool (*notify)(struct virtqueue *vq); > > struct virtqueue *vq; > > u16 num; > > int err; > > > > + if (__virtio_test_bit(&vp_dev->vdev, VIRTIO_F_NOTIFICATION_DATA)) > > + notify = vp_notify_with_data; > > + else > > + notify = vp_notify; > > + > > if (index >= vp_modern_get_num_queues(mdev)) > > return ERR_PTR(-EINVAL); > > > > @@ -321,7 +336,7 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev, > > vq = vring_create_virtqueue(index, num, > > SMP_CACHE_BYTES, &vp_dev->vdev, > > true, true, ctx, > > - vp_notify, callback, name); > > + notify, callback, name); > > if (!vq) > > return ERR_PTR(-ENOMEM); > > > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > > index 4c3bb0ddeb9b..f9c6604352b4 100644 > > --- a/drivers/virtio/virtio_ring.c > > +++ b/drivers/virtio/virtio_ring.c > > @@ -2752,6 +2752,23 @@ void vring_del_virtqueue(struct virtqueue *_vq) > > } > > EXPORT_SYMBOL_GPL(vring_del_virtqueue); > > > > +u32 vring_notification_data(struct virtqueue *_vq) > > +{ > > + struct vring_virtqueue *vq = to_vvq(_vq); > > + u16 next; > > + > > + if (vq->packed_ring) > > + next = (vq->packed.next_avail_idx & > > + ~(-(1 << VRING_PACKED_EVENT_F_WRAP_CTR))) | > > + vq->packed.avail_wrap_counter << > > + VRING_PACKED_EVENT_F_WRAP_CTR; > > + else > > + next = vq->split.avail_idx_shadow; > > + > > + return next << 16 | _vq->index; > > +} > > +EXPORT_SYMBOL_GPL(vring_notification_data); > > + > > /* Manipulates transport-specific feature bits. */ > > void vring_transport_features(struct virtio_device *vdev) > > { > > @@ -2771,6 +2788,8 @@ void vring_transport_features(struct virtio_device *vdev) > > break; > > case VIRTIO_F_ORDER_PLATFORM: > > break; > > + case VIRTIO_F_NOTIFICATION_DATA: > > + break; > > default: > > /* We don't understand this bit. */ > > __virtio_clear_bit(vdev, i); > > diff --git a/include/linux/virtio_ring.h b/include/linux/virtio_ring.h > > index 8b95b69ef694..2550c9170f4f 100644 > > --- a/include/linux/virtio_ring.h > > +++ b/include/linux/virtio_ring.h > > @@ -117,4 +117,6 @@ void vring_del_virtqueue(struct virtqueue *vq); > > void vring_transport_features(struct virtio_device *vdev); > > > > irqreturn_t vring_interrupt(int irq, void *_vq); > > + > > +u32 vring_notification_data(struct virtqueue *_vq); > > #endif /* _LINUX_VIRTIO_RING_H */ > > diff --git a/include/uapi/linux/virtio_config.h b/include/uapi/linux/virtio_config.h > > index 3c05162bc988..2c712c654165 100644 > > --- a/include/uapi/linux/virtio_config.h > > +++ b/include/uapi/linux/virtio_config.h > > @@ -99,6 +99,12 @@ > > */ > > #define VIRTIO_F_SR_IOV 37 > > > > +/* > > + * This feature indicates that the driver passes extra data (besides > > + * identifying the virtqueue) in its device notifications. > > + */ > > +#define VIRTIO_F_NOTIFICATION_DATA 38 > > + > > /* > > * This feature indicates that the driver can reset a queue individually. > > */ > > -- > > 2.35.1 > > > > pingGenerally speaking, Michael will merge patch here and will not reply in the mail list. You can see it here. https://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git/log/?h=linux-next At present, this patch has not been merged, and you need to give Micheal some time. Thanks.