| Message ID | 20220406034346.74409-24-xuanzhuo@linux.alibaba.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | virtio pci support VIRTIO_F_RING_RESET (refactor vring) | expand |
在 2022/4/6 上午11:43, Xuan Zhuo 写道: > This patch implements virtio pci support for QUEUE RESET. > > Performing reset on a queue is divided into these steps: > > 1. notify the device to reset the queue > 2. recycle the buffer submitted > 3. reset the vring (may re-alloc) > 4. mmap vring to device, and enable the queue > > This patch implements virtio_reset_vq(), virtio_enable_resetq() in the > pci scenario. > > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > --- > drivers/virtio/virtio_pci_common.c | 8 +-- > drivers/virtio/virtio_pci_modern.c | 84 ++++++++++++++++++++++++++++++ > drivers/virtio/virtio_ring.c | 2 + > include/linux/virtio.h | 1 + > 4 files changed, 92 insertions(+), 3 deletions(-) > > diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c > index fdbde1db5ec5..863d3a8a0956 100644 > --- a/drivers/virtio/virtio_pci_common.c > +++ b/drivers/virtio/virtio_pci_common.c > @@ -248,9 +248,11 @@ static void vp_del_vq(struct virtqueue *vq) > struct virtio_pci_vq_info *info = vp_dev->vqs[vq->index]; > unsigned long flags; > > - spin_lock_irqsave(&vp_dev->lock, flags); > - list_del(&info->node); > - spin_unlock_irqrestore(&vp_dev->lock, flags); > + if (!vq->reset) { On which condition that we may hit this path? > + spin_lock_irqsave(&vp_dev->lock, flags); > + list_del(&info->node); > + spin_unlock_irqrestore(&vp_dev->lock, flags); > + } > > vp_dev->del_vq(info); > kfree(info); > diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c > index 49a4493732cf..cb5d38f1c9c8 100644 > --- a/drivers/virtio/virtio_pci_modern.c > +++ b/drivers/virtio/virtio_pci_modern.c > @@ -34,6 +34,9 @@ static void vp_transport_features(struct virtio_device *vdev, u64 features) > if ((features & BIT_ULL(VIRTIO_F_SR_IOV)) && > pci_find_ext_capability(pci_dev, PCI_EXT_CAP_ID_SRIOV)) > __virtio_set_bit(vdev, VIRTIO_F_SR_IOV); > + > + if (features & BIT_ULL(VIRTIO_F_RING_RESET)) > + __virtio_set_bit(vdev, VIRTIO_F_RING_RESET); > } > > /* virtio config->finalize_features() implementation */ > @@ -199,6 +202,83 @@ static int vp_active_vq(struct virtqueue *vq, u16 msix_vec) > return 0; > } > > +static int vp_modern_reset_vq(struct virtqueue *vq) > +{ > + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); > + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > + struct virtio_pci_vq_info *info; > + unsigned long flags; > + > + if (!virtio_has_feature(vq->vdev, VIRTIO_F_RING_RESET)) > + return -ENOENT; > + > + vp_modern_set_queue_reset(mdev, vq->index); > + > + info = vp_dev->vqs[vq->index]; > + > + /* delete vq from irq handler */ > + spin_lock_irqsave(&vp_dev->lock, flags); > + list_del(&info->node); > + spin_unlock_irqrestore(&vp_dev->lock, flags); > + > + INIT_LIST_HEAD(&info->node); > + > + /* For the case where vq has an exclusive irq, to prevent the irq from > + * being received again and the pending irq, call disable_irq(). > + * > + * In the scenario based on shared interrupts, vq will be searched from > + * the queue virtqueues. Since the previous list_del() has been deleted > + * from the queue, it is impossible for vq to be called in this case. > + * There is no need to close the corresponding interrupt. > + */ > + if (vp_dev->per_vq_vectors && info->msix_vector != VIRTIO_MSI_NO_VECTOR) > + disable_irq(pci_irq_vector(vp_dev->pci_dev, info->msix_vector)); See the previous discussion and the revert of the first try to harden the interrupt. We probably can't use disable_irq() since it conflicts with the affinity managed IRQ that is used by some drivers. We need to use synchonize_irq() and per virtqueue flag instead. As mentioned in previous patches, this could be done on top of my rework on the IRQ hardening . > + > + vq->reset = true; > + > + return 0; > +} > + > +static int vp_modern_enable_reset_vq(struct virtqueue *vq) > +{ > + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); > + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > + struct virtio_pci_vq_info *info; > + unsigned long flags, index; > + int err; > + > + if (!vq->reset) > + return -EBUSY; > + > + index = vq->index; > + info = vp_dev->vqs[index]; > + > + /* check queue reset status */ > + if (vp_modern_get_queue_reset(mdev, index) != 1) > + return -EBUSY; > + > + err = vp_active_vq(vq, info->msix_vector); > + if (err) > + return err; > + > + if (vq->callback) { > + spin_lock_irqsave(&vp_dev->lock, flags); > + list_add(&info->node, &vp_dev->virtqueues); > + spin_unlock_irqrestore(&vp_dev->lock, flags); > + } else { > + INIT_LIST_HEAD(&info->node); > + } > + > + vp_modern_set_queue_enable(&vp_dev->mdev, index, true); > + > + if (vp_dev->per_vq_vectors && info->msix_vector != VIRTIO_MSI_NO_VECTOR) > + enable_irq(pci_irq_vector(vp_dev->pci_dev, info->msix_vector)); We had the same issue as disable_irq(). Thanks > + > + vq->reset = false; > + > + return 0; > +} > + > static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) > { > return vp_modern_config_vector(&vp_dev->mdev, vector); > @@ -407,6 +487,8 @@ static const struct virtio_config_ops virtio_pci_config_nodev_ops = { > .set_vq_affinity = vp_set_vq_affinity, > .get_vq_affinity = vp_get_vq_affinity, > .get_shm_region = vp_get_shm_region, > + .reset_vq = vp_modern_reset_vq, > + .enable_reset_vq = vp_modern_enable_reset_vq, > }; > > static const struct virtio_config_ops virtio_pci_config_ops = { > @@ -425,6 +507,8 @@ static const struct virtio_config_ops virtio_pci_config_ops = { > .set_vq_affinity = vp_set_vq_affinity, > .get_vq_affinity = vp_get_vq_affinity, > .get_shm_region = vp_get_shm_region, > + .reset_vq = vp_modern_reset_vq, > + .enable_reset_vq = vp_modern_enable_reset_vq, > }; > > /* the PCI probing function */ > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > index 6250e19fc5bf..91937e21edca 100644 > --- a/drivers/virtio/virtio_ring.c > +++ b/drivers/virtio/virtio_ring.c > @@ -2028,6 +2028,7 @@ static struct virtqueue *vring_create_virtqueue_packed( > vq->vq.vdev = vdev; > vq->vq.name = name; > vq->vq.index = index; > + vq->vq.reset = false; > vq->notify = notify; > vq->weak_barriers = weak_barriers; > > @@ -2508,6 +2509,7 @@ struct virtqueue *__vring_new_virtqueue(unsigned int index, > vq->vq.vdev = vdev; > vq->vq.name = name; > vq->vq.index = index; > + vq->vq.reset = false; > vq->notify = notify; > vq->weak_barriers = weak_barriers; > > diff --git a/include/linux/virtio.h b/include/linux/virtio.h > index c86ff02e0ca0..33ab003c5100 100644 > --- a/include/linux/virtio.h > +++ b/include/linux/virtio.h > @@ -33,6 +33,7 @@ struct virtqueue { > unsigned int num_free; > unsigned int num_max; > void *priv; > + bool reset; > }; > > int virtqueue_add_outbuf(struct virtqueue *vq,
On Tue, 12 Apr 2022 15:07:58 +0800, Jason Wang <jasowang@redhat.com> wrote: > > 在 2022/4/6 上午11:43, Xuan Zhuo 写道: > > This patch implements virtio pci support for QUEUE RESET. > > > > Performing reset on a queue is divided into these steps: > > > > 1. notify the device to reset the queue > > 2. recycle the buffer submitted > > 3. reset the vring (may re-alloc) > > 4. mmap vring to device, and enable the queue > > > > This patch implements virtio_reset_vq(), virtio_enable_resetq() in the > > pci scenario. > > > > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > > --- > > drivers/virtio/virtio_pci_common.c | 8 +-- > > drivers/virtio/virtio_pci_modern.c | 84 ++++++++++++++++++++++++++++++ > > drivers/virtio/virtio_ring.c | 2 + > > include/linux/virtio.h | 1 + > > 4 files changed, 92 insertions(+), 3 deletions(-) > > > > diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c > > index fdbde1db5ec5..863d3a8a0956 100644 > > --- a/drivers/virtio/virtio_pci_common.c > > +++ b/drivers/virtio/virtio_pci_common.c > > @@ -248,9 +248,11 @@ static void vp_del_vq(struct virtqueue *vq) > > struct virtio_pci_vq_info *info = vp_dev->vqs[vq->index]; > > unsigned long flags; > > > > - spin_lock_irqsave(&vp_dev->lock, flags); > > - list_del(&info->node); > > - spin_unlock_irqrestore(&vp_dev->lock, flags); > > + if (!vq->reset) { > > > On which condition that we may hit this path? > > > > + spin_lock_irqsave(&vp_dev->lock, flags); > > + list_del(&info->node); > > + spin_unlock_irqrestore(&vp_dev->lock, flags); > > + } > > > > vp_dev->del_vq(info); > > kfree(info); > > diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c > > index 49a4493732cf..cb5d38f1c9c8 100644 > > --- a/drivers/virtio/virtio_pci_modern.c > > +++ b/drivers/virtio/virtio_pci_modern.c > > @@ -34,6 +34,9 @@ static void vp_transport_features(struct virtio_device *vdev, u64 features) > > if ((features & BIT_ULL(VIRTIO_F_SR_IOV)) && > > pci_find_ext_capability(pci_dev, PCI_EXT_CAP_ID_SRIOV)) > > __virtio_set_bit(vdev, VIRTIO_F_SR_IOV); > > + > > + if (features & BIT_ULL(VIRTIO_F_RING_RESET)) > > + __virtio_set_bit(vdev, VIRTIO_F_RING_RESET); > > } > > > > /* virtio config->finalize_features() implementation */ > > @@ -199,6 +202,83 @@ static int vp_active_vq(struct virtqueue *vq, u16 msix_vec) > > return 0; > > } > > > > +static int vp_modern_reset_vq(struct virtqueue *vq) > > +{ > > + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); > > + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > > + struct virtio_pci_vq_info *info; > > + unsigned long flags; > > + > > + if (!virtio_has_feature(vq->vdev, VIRTIO_F_RING_RESET)) > > + return -ENOENT; > > + > > + vp_modern_set_queue_reset(mdev, vq->index); > > + > > + info = vp_dev->vqs[vq->index]; > > + > > + /* delete vq from irq handler */ > > + spin_lock_irqsave(&vp_dev->lock, flags); > > + list_del(&info->node); > > + spin_unlock_irqrestore(&vp_dev->lock, flags); > > + > > + INIT_LIST_HEAD(&info->node); > > + > > + /* For the case where vq has an exclusive irq, to prevent the irq from > > + * being received again and the pending irq, call disable_irq(). > > + * > > + * In the scenario based on shared interrupts, vq will be searched from > > + * the queue virtqueues. Since the previous list_del() has been deleted > > + * from the queue, it is impossible for vq to be called in this case. > > + * There is no need to close the corresponding interrupt. > > + */ > > + if (vp_dev->per_vq_vectors && info->msix_vector != VIRTIO_MSI_NO_VECTOR) > > + disable_irq(pci_irq_vector(vp_dev->pci_dev, info->msix_vector)); > > > See the previous discussion and the revert of the first try to harden > the interrupt. We probably can't use disable_irq() since it conflicts > with the affinity managed IRQ that is used by some drivers. > > We need to use synchonize_irq() and per virtqueue flag instead. As > mentioned in previous patches, this could be done on top of my rework on > the IRQ hardening . OK, the next version will contain hardened features by per virtqueue flag. Thanks. > > > > + > > + vq->reset = true; > > + > > + return 0; > > +} > > + > > +static int vp_modern_enable_reset_vq(struct virtqueue *vq) > > +{ > > + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); > > + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > > + struct virtio_pci_vq_info *info; > > + unsigned long flags, index; > > + int err; > > + > > + if (!vq->reset) > > + return -EBUSY; > > + > > + index = vq->index; > > + info = vp_dev->vqs[index]; > > + > > + /* check queue reset status */ > > + if (vp_modern_get_queue_reset(mdev, index) != 1) > > + return -EBUSY; > > + > > + err = vp_active_vq(vq, info->msix_vector); > > + if (err) > > + return err; > > + > > + if (vq->callback) { > > + spin_lock_irqsave(&vp_dev->lock, flags); > > + list_add(&info->node, &vp_dev->virtqueues); > > + spin_unlock_irqrestore(&vp_dev->lock, flags); > > + } else { > > + INIT_LIST_HEAD(&info->node); > > + } > > + > > + vp_modern_set_queue_enable(&vp_dev->mdev, index, true); > > + > > + if (vp_dev->per_vq_vectors && info->msix_vector != VIRTIO_MSI_NO_VECTOR) > > + enable_irq(pci_irq_vector(vp_dev->pci_dev, info->msix_vector)); > > > We had the same issue as disable_irq(). > > Thanks > > > > + > > + vq->reset = false; > > + > > + return 0; > > +} > > + > > static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) > > { > > return vp_modern_config_vector(&vp_dev->mdev, vector); > > @@ -407,6 +487,8 @@ static const struct virtio_config_ops virtio_pci_config_nodev_ops = { > > .set_vq_affinity = vp_set_vq_affinity, > > .get_vq_affinity = vp_get_vq_affinity, > > .get_shm_region = vp_get_shm_region, > > + .reset_vq = vp_modern_reset_vq, > > + .enable_reset_vq = vp_modern_enable_reset_vq, > > }; > > > > static const struct virtio_config_ops virtio_pci_config_ops = { > > @@ -425,6 +507,8 @@ static const struct virtio_config_ops virtio_pci_config_ops = { > > .set_vq_affinity = vp_set_vq_affinity, > > .get_vq_affinity = vp_get_vq_affinity, > > .get_shm_region = vp_get_shm_region, > > + .reset_vq = vp_modern_reset_vq, > > + .enable_reset_vq = vp_modern_enable_reset_vq, > > }; > > > > /* the PCI probing function */ > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > > index 6250e19fc5bf..91937e21edca 100644 > > --- a/drivers/virtio/virtio_ring.c > > +++ b/drivers/virtio/virtio_ring.c > > @@ -2028,6 +2028,7 @@ static struct virtqueue *vring_create_virtqueue_packed( > > vq->vq.vdev = vdev; > > vq->vq.name = name; > > vq->vq.index = index; > > + vq->vq.reset = false; > > vq->notify = notify; > > vq->weak_barriers = weak_barriers; > > > > @@ -2508,6 +2509,7 @@ struct virtqueue *__vring_new_virtqueue(unsigned int index, > > vq->vq.vdev = vdev; > > vq->vq.name = name; > > vq->vq.index = index; > > + vq->vq.reset = false; > > vq->notify = notify; > > vq->weak_barriers = weak_barriers; > > > > diff --git a/include/linux/virtio.h b/include/linux/virtio.h > > index c86ff02e0ca0..33ab003c5100 100644 > > --- a/include/linux/virtio.h > > +++ b/include/linux/virtio.h > > @@ -33,6 +33,7 @@ struct virtqueue { > > unsigned int num_free; > > unsigned int num_max; > > void *priv; > > + bool reset; > > }; > > > > int virtqueue_add_outbuf(struct virtqueue *vq, >
On Tue, 12 Apr 2022 15:07:58 +0800, Jason Wang <jasowang@redhat.com> wrote: > > 在 2022/4/6 上午11:43, Xuan Zhuo 写道: > > This patch implements virtio pci support for QUEUE RESET. > > > > Performing reset on a queue is divided into these steps: > > > > 1. notify the device to reset the queue > > 2. recycle the buffer submitted > > 3. reset the vring (may re-alloc) > > 4. mmap vring to device, and enable the queue > > > > This patch implements virtio_reset_vq(), virtio_enable_resetq() in the > > pci scenario. > > > > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > > --- > > drivers/virtio/virtio_pci_common.c | 8 +-- > > drivers/virtio/virtio_pci_modern.c | 84 ++++++++++++++++++++++++++++++ > > drivers/virtio/virtio_ring.c | 2 + > > include/linux/virtio.h | 1 + > > 4 files changed, 92 insertions(+), 3 deletions(-) > > > > diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c > > index fdbde1db5ec5..863d3a8a0956 100644 > > --- a/drivers/virtio/virtio_pci_common.c > > +++ b/drivers/virtio/virtio_pci_common.c > > @@ -248,9 +248,11 @@ static void vp_del_vq(struct virtqueue *vq) > > struct virtio_pci_vq_info *info = vp_dev->vqs[vq->index]; > > unsigned long flags; > > > > - spin_lock_irqsave(&vp_dev->lock, flags); > > - list_del(&info->node); > > - spin_unlock_irqrestore(&vp_dev->lock, flags); > > + if (!vq->reset) { > > > On which condition that we may hit this path? As discussed in patch 31, it may fail when renable vq. Thanks. > > > > + spin_lock_irqsave(&vp_dev->lock, flags); > > + list_del(&info->node); > > + spin_unlock_irqrestore(&vp_dev->lock, flags); > > + } > > > > vp_dev->del_vq(info); > > kfree(info); > > diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c > > index 49a4493732cf..cb5d38f1c9c8 100644 > > --- a/drivers/virtio/virtio_pci_modern.c > > +++ b/drivers/virtio/virtio_pci_modern.c > > @@ -34,6 +34,9 @@ static void vp_transport_features(struct virtio_device *vdev, u64 features) > > if ((features & BIT_ULL(VIRTIO_F_SR_IOV)) && > > pci_find_ext_capability(pci_dev, PCI_EXT_CAP_ID_SRIOV)) > > __virtio_set_bit(vdev, VIRTIO_F_SR_IOV); > > + > > + if (features & BIT_ULL(VIRTIO_F_RING_RESET)) > > + __virtio_set_bit(vdev, VIRTIO_F_RING_RESET); > > } > > > > /* virtio config->finalize_features() implementation */ > > @@ -199,6 +202,83 @@ static int vp_active_vq(struct virtqueue *vq, u16 msix_vec) > > return 0; > > } > > > > +static int vp_modern_reset_vq(struct virtqueue *vq) > > +{ > > + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); > > + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > > + struct virtio_pci_vq_info *info; > > + unsigned long flags; > > + > > + if (!virtio_has_feature(vq->vdev, VIRTIO_F_RING_RESET)) > > + return -ENOENT; > > + > > + vp_modern_set_queue_reset(mdev, vq->index); > > + > > + info = vp_dev->vqs[vq->index]; > > + > > + /* delete vq from irq handler */ > > + spin_lock_irqsave(&vp_dev->lock, flags); > > + list_del(&info->node); > > + spin_unlock_irqrestore(&vp_dev->lock, flags); > > + > > + INIT_LIST_HEAD(&info->node); > > + > > + /* For the case where vq has an exclusive irq, to prevent the irq from > > + * being received again and the pending irq, call disable_irq(). > > + * > > + * In the scenario based on shared interrupts, vq will be searched from > > + * the queue virtqueues. Since the previous list_del() has been deleted > > + * from the queue, it is impossible for vq to be called in this case. > > + * There is no need to close the corresponding interrupt. > > + */ > > + if (vp_dev->per_vq_vectors && info->msix_vector != VIRTIO_MSI_NO_VECTOR) > > + disable_irq(pci_irq_vector(vp_dev->pci_dev, info->msix_vector)); > > > See the previous discussion and the revert of the first try to harden > the interrupt. We probably can't use disable_irq() since it conflicts > with the affinity managed IRQ that is used by some drivers. > > We need to use synchonize_irq() and per virtqueue flag instead. As > mentioned in previous patches, this could be done on top of my rework on > the IRQ hardening . > > > > + > > + vq->reset = true; > > + > > + return 0; > > +} > > + > > +static int vp_modern_enable_reset_vq(struct virtqueue *vq) > > +{ > > + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); > > + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > > + struct virtio_pci_vq_info *info; > > + unsigned long flags, index; > > + int err; > > + > > + if (!vq->reset) > > + return -EBUSY; > > + > > + index = vq->index; > > + info = vp_dev->vqs[index]; > > + > > + /* check queue reset status */ > > + if (vp_modern_get_queue_reset(mdev, index) != 1) > > + return -EBUSY; > > + > > + err = vp_active_vq(vq, info->msix_vector); > > + if (err) > > + return err; > > + > > + if (vq->callback) { > > + spin_lock_irqsave(&vp_dev->lock, flags); > > + list_add(&info->node, &vp_dev->virtqueues); > > + spin_unlock_irqrestore(&vp_dev->lock, flags); > > + } else { > > + INIT_LIST_HEAD(&info->node); > > + } > > + > > + vp_modern_set_queue_enable(&vp_dev->mdev, index, true); > > + > > + if (vp_dev->per_vq_vectors && info->msix_vector != VIRTIO_MSI_NO_VECTOR) > > + enable_irq(pci_irq_vector(vp_dev->pci_dev, info->msix_vector)); > > > We had the same issue as disable_irq(). > > Thanks > > > > + > > + vq->reset = false; > > + > > + return 0; > > +} > > + > > static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) > > { > > return vp_modern_config_vector(&vp_dev->mdev, vector); > > @@ -407,6 +487,8 @@ static const struct virtio_config_ops virtio_pci_config_nodev_ops = { > > .set_vq_affinity = vp_set_vq_affinity, > > .get_vq_affinity = vp_get_vq_affinity, > > .get_shm_region = vp_get_shm_region, > > + .reset_vq = vp_modern_reset_vq, > > + .enable_reset_vq = vp_modern_enable_reset_vq, > > }; > > > > static const struct virtio_config_ops virtio_pci_config_ops = { > > @@ -425,6 +507,8 @@ static const struct virtio_config_ops virtio_pci_config_ops = { > > .set_vq_affinity = vp_set_vq_affinity, > > .get_vq_affinity = vp_get_vq_affinity, > > .get_shm_region = vp_get_shm_region, > > + .reset_vq = vp_modern_reset_vq, > > + .enable_reset_vq = vp_modern_enable_reset_vq, > > }; > > > > /* the PCI probing function */ > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > > index 6250e19fc5bf..91937e21edca 100644 > > --- a/drivers/virtio/virtio_ring.c > > +++ b/drivers/virtio/virtio_ring.c > > @@ -2028,6 +2028,7 @@ static struct virtqueue *vring_create_virtqueue_packed( > > vq->vq.vdev = vdev; > > vq->vq.name = name; > > vq->vq.index = index; > > + vq->vq.reset = false; > > vq->notify = notify; > > vq->weak_barriers = weak_barriers; > > > > @@ -2508,6 +2509,7 @@ struct virtqueue *__vring_new_virtqueue(unsigned int index, > > vq->vq.vdev = vdev; > > vq->vq.name = name; > > vq->vq.index = index; > > + vq->vq.reset = false; > > vq->notify = notify; > > vq->weak_barriers = weak_barriers; > > > > diff --git a/include/linux/virtio.h b/include/linux/virtio.h > > index c86ff02e0ca0..33ab003c5100 100644 > > --- a/include/linux/virtio.h > > +++ b/include/linux/virtio.h > > @@ -33,6 +33,7 @@ struct virtqueue { > > unsigned int num_free; > > unsigned int num_max; > > void *priv; > > + bool reset; > > }; > > > > int virtqueue_add_outbuf(struct virtqueue *vq, >
On Wed, Apr 13, 2022 at 11:23 AM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote: > > On Tue, 12 Apr 2022 15:07:58 +0800, Jason Wang <jasowang@redhat.com> wrote: > > > > 在 2022/4/6 上午11:43, Xuan Zhuo 写道: > > > This patch implements virtio pci support for QUEUE RESET. > > > > > > Performing reset on a queue is divided into these steps: > > > > > > 1. notify the device to reset the queue > > > 2. recycle the buffer submitted > > > 3. reset the vring (may re-alloc) > > > 4. mmap vring to device, and enable the queue > > > > > > This patch implements virtio_reset_vq(), virtio_enable_resetq() in the > > > pci scenario. > > > > > > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > > > --- > > > drivers/virtio/virtio_pci_common.c | 8 +-- > > > drivers/virtio/virtio_pci_modern.c | 84 ++++++++++++++++++++++++++++++ > > > drivers/virtio/virtio_ring.c | 2 + > > > include/linux/virtio.h | 1 + > > > 4 files changed, 92 insertions(+), 3 deletions(-) > > > > > > diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c > > > index fdbde1db5ec5..863d3a8a0956 100644 > > > --- a/drivers/virtio/virtio_pci_common.c > > > +++ b/drivers/virtio/virtio_pci_common.c > > > @@ -248,9 +248,11 @@ static void vp_del_vq(struct virtqueue *vq) > > > struct virtio_pci_vq_info *info = vp_dev->vqs[vq->index]; > > > unsigned long flags; > > > > > > - spin_lock_irqsave(&vp_dev->lock, flags); > > > - list_del(&info->node); > > > - spin_unlock_irqrestore(&vp_dev->lock, flags); > > > + if (!vq->reset) { > > > > > > On which condition that we may hit this path? > > > > > > > + spin_lock_irqsave(&vp_dev->lock, flags); > > > + list_del(&info->node); > > > + spin_unlock_irqrestore(&vp_dev->lock, flags); > > > + } > > > > > > vp_dev->del_vq(info); > > > kfree(info); > > > diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c > > > index 49a4493732cf..cb5d38f1c9c8 100644 > > > --- a/drivers/virtio/virtio_pci_modern.c > > > +++ b/drivers/virtio/virtio_pci_modern.c > > > @@ -34,6 +34,9 @@ static void vp_transport_features(struct virtio_device *vdev, u64 features) > > > if ((features & BIT_ULL(VIRTIO_F_SR_IOV)) && > > > pci_find_ext_capability(pci_dev, PCI_EXT_CAP_ID_SRIOV)) > > > __virtio_set_bit(vdev, VIRTIO_F_SR_IOV); > > > + > > > + if (features & BIT_ULL(VIRTIO_F_RING_RESET)) > > > + __virtio_set_bit(vdev, VIRTIO_F_RING_RESET); > > > } > > > > > > /* virtio config->finalize_features() implementation */ > > > @@ -199,6 +202,83 @@ static int vp_active_vq(struct virtqueue *vq, u16 msix_vec) > > > return 0; > > > } > > > > > > +static int vp_modern_reset_vq(struct virtqueue *vq) > > > +{ > > > + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); > > > + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > > > + struct virtio_pci_vq_info *info; > > > + unsigned long flags; > > > + > > > + if (!virtio_has_feature(vq->vdev, VIRTIO_F_RING_RESET)) > > > + return -ENOENT; > > > + > > > + vp_modern_set_queue_reset(mdev, vq->index); > > > + > > > + info = vp_dev->vqs[vq->index]; > > > + > > > + /* delete vq from irq handler */ > > > + spin_lock_irqsave(&vp_dev->lock, flags); > > > + list_del(&info->node); > > > + spin_unlock_irqrestore(&vp_dev->lock, flags); > > > + > > > + INIT_LIST_HEAD(&info->node); > > > + > > > + /* For the case where vq has an exclusive irq, to prevent the irq from > > > + * being received again and the pending irq, call disable_irq(). > > > + * > > > + * In the scenario based on shared interrupts, vq will be searched from > > > + * the queue virtqueues. Since the previous list_del() has been deleted > > > + * from the queue, it is impossible for vq to be called in this case. > > > + * There is no need to close the corresponding interrupt. > > > + */ > > > + if (vp_dev->per_vq_vectors && info->msix_vector != VIRTIO_MSI_NO_VECTOR) > > > + disable_irq(pci_irq_vector(vp_dev->pci_dev, info->msix_vector)); > > > > > > See the previous discussion and the revert of the first try to harden > > the interrupt. We probably can't use disable_irq() since it conflicts > > with the affinity managed IRQ that is used by some drivers. > > > > We need to use synchonize_irq() and per virtqueue flag instead. As > > mentioned in previous patches, this could be done on top of my rework on > > the IRQ hardening . > > OK, the next version will contain hardened features by per virtqueue flag. Actually, I'm working on a new version of hardening. I plan to switch to the virtqueue flag so we will be fine here if we do the resize work on top. I will cc you in the new version. Thanks > > Thanks. > > > > > > > > + > > > + vq->reset = true; > > > + > > > + return 0; > > > +} > > > + > > > +static int vp_modern_enable_reset_vq(struct virtqueue *vq) > > > +{ > > > + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); > > > + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > > > + struct virtio_pci_vq_info *info; > > > + unsigned long flags, index; > > > + int err; > > > + > > > + if (!vq->reset) > > > + return -EBUSY; > > > + > > > + index = vq->index; > > > + info = vp_dev->vqs[index]; > > > + > > > + /* check queue reset status */ > > > + if (vp_modern_get_queue_reset(mdev, index) != 1) > > > + return -EBUSY; > > > + > > > + err = vp_active_vq(vq, info->msix_vector); > > > + if (err) > > > + return err; > > > + > > > + if (vq->callback) { > > > + spin_lock_irqsave(&vp_dev->lock, flags); > > > + list_add(&info->node, &vp_dev->virtqueues); > > > + spin_unlock_irqrestore(&vp_dev->lock, flags); > > > + } else { > > > + INIT_LIST_HEAD(&info->node); > > > + } > > > + > > > + vp_modern_set_queue_enable(&vp_dev->mdev, index, true); > > > + > > > + if (vp_dev->per_vq_vectors && info->msix_vector != VIRTIO_MSI_NO_VECTOR) > > > + enable_irq(pci_irq_vector(vp_dev->pci_dev, info->msix_vector)); > > > > > > We had the same issue as disable_irq(). > > > > Thanks > > > > > > > + > > > + vq->reset = false; > > > + > > > + return 0; > > > +} > > > + > > > static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) > > > { > > > return vp_modern_config_vector(&vp_dev->mdev, vector); > > > @@ -407,6 +487,8 @@ static const struct virtio_config_ops virtio_pci_config_nodev_ops = { > > > .set_vq_affinity = vp_set_vq_affinity, > > > .get_vq_affinity = vp_get_vq_affinity, > > > .get_shm_region = vp_get_shm_region, > > > + .reset_vq = vp_modern_reset_vq, > > > + .enable_reset_vq = vp_modern_enable_reset_vq, > > > }; > > > > > > static const struct virtio_config_ops virtio_pci_config_ops = { > > > @@ -425,6 +507,8 @@ static const struct virtio_config_ops virtio_pci_config_ops = { > > > .set_vq_affinity = vp_set_vq_affinity, > > > .get_vq_affinity = vp_get_vq_affinity, > > > .get_shm_region = vp_get_shm_region, > > > + .reset_vq = vp_modern_reset_vq, > > > + .enable_reset_vq = vp_modern_enable_reset_vq, > > > }; > > > > > > /* the PCI probing function */ > > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > > > index 6250e19fc5bf..91937e21edca 100644 > > > --- a/drivers/virtio/virtio_ring.c > > > +++ b/drivers/virtio/virtio_ring.c > > > @@ -2028,6 +2028,7 @@ static struct virtqueue *vring_create_virtqueue_packed( > > > vq->vq.vdev = vdev; > > > vq->vq.name = name; > > > vq->vq.index = index; > > > + vq->vq.reset = false; > > > vq->notify = notify; > > > vq->weak_barriers = weak_barriers; > > > > > > @@ -2508,6 +2509,7 @@ struct virtqueue *__vring_new_virtqueue(unsigned int index, > > > vq->vq.vdev = vdev; > > > vq->vq.name = name; > > > vq->vq.index = index; > > > + vq->vq.reset = false; > > > vq->notify = notify; > > > vq->weak_barriers = weak_barriers; > > > > > > diff --git a/include/linux/virtio.h b/include/linux/virtio.h > > > index c86ff02e0ca0..33ab003c5100 100644 > > > --- a/include/linux/virtio.h > > > +++ b/include/linux/virtio.h > > > @@ -33,6 +33,7 @@ struct virtqueue { > > > unsigned int num_free; > > > unsigned int num_max; > > > void *priv; > > > + bool reset; > > > }; > > > > > > int virtqueue_add_outbuf(struct virtqueue *vq, > > >
diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c index fdbde1db5ec5..863d3a8a0956 100644 --- a/drivers/virtio/virtio_pci_common.c +++ b/drivers/virtio/virtio_pci_common.c @@ -248,9 +248,11 @@ static void vp_del_vq(struct virtqueue *vq) struct virtio_pci_vq_info *info = vp_dev->vqs[vq->index]; unsigned long flags; - spin_lock_irqsave(&vp_dev->lock, flags); - list_del(&info->node); - spin_unlock_irqrestore(&vp_dev->lock, flags); + if (!vq->reset) { + spin_lock_irqsave(&vp_dev->lock, flags); + list_del(&info->node); + spin_unlock_irqrestore(&vp_dev->lock, flags); + } vp_dev->del_vq(info); kfree(info); diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c index 49a4493732cf..cb5d38f1c9c8 100644 --- a/drivers/virtio/virtio_pci_modern.c +++ b/drivers/virtio/virtio_pci_modern.c @@ -34,6 +34,9 @@ static void vp_transport_features(struct virtio_device *vdev, u64 features) if ((features & BIT_ULL(VIRTIO_F_SR_IOV)) && pci_find_ext_capability(pci_dev, PCI_EXT_CAP_ID_SRIOV)) __virtio_set_bit(vdev, VIRTIO_F_SR_IOV); + + if (features & BIT_ULL(VIRTIO_F_RING_RESET)) + __virtio_set_bit(vdev, VIRTIO_F_RING_RESET); } /* virtio config->finalize_features() implementation */ @@ -199,6 +202,83 @@ static int vp_active_vq(struct virtqueue *vq, u16 msix_vec) return 0; } +static int vp_modern_reset_vq(struct virtqueue *vq) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + struct virtio_pci_vq_info *info; + unsigned long flags; + + if (!virtio_has_feature(vq->vdev, VIRTIO_F_RING_RESET)) + return -ENOENT; + + vp_modern_set_queue_reset(mdev, vq->index); + + info = vp_dev->vqs[vq->index]; + + /* delete vq from irq handler */ + spin_lock_irqsave(&vp_dev->lock, flags); + list_del(&info->node); + spin_unlock_irqrestore(&vp_dev->lock, flags); + + INIT_LIST_HEAD(&info->node); + + /* For the case where vq has an exclusive irq, to prevent the irq from + * being received again and the pending irq, call disable_irq(). + * + * In the scenario based on shared interrupts, vq will be searched from + * the queue virtqueues. Since the previous list_del() has been deleted + * from the queue, it is impossible for vq to be called in this case. + * There is no need to close the corresponding interrupt. + */ + if (vp_dev->per_vq_vectors && info->msix_vector != VIRTIO_MSI_NO_VECTOR) + disable_irq(pci_irq_vector(vp_dev->pci_dev, info->msix_vector)); + + vq->reset = true; + + return 0; +} + +static int vp_modern_enable_reset_vq(struct virtqueue *vq) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + struct virtio_pci_vq_info *info; + unsigned long flags, index; + int err; + + if (!vq->reset) + return -EBUSY; + + index = vq->index; + info = vp_dev->vqs[index]; + + /* check queue reset status */ + if (vp_modern_get_queue_reset(mdev, index) != 1) + return -EBUSY; + + err = vp_active_vq(vq, info->msix_vector); + if (err) + return err; + + if (vq->callback) { + spin_lock_irqsave(&vp_dev->lock, flags); + list_add(&info->node, &vp_dev->virtqueues); + spin_unlock_irqrestore(&vp_dev->lock, flags); + } else { + INIT_LIST_HEAD(&info->node); + } + + vp_modern_set_queue_enable(&vp_dev->mdev, index, true); + + if (vp_dev->per_vq_vectors && info->msix_vector != VIRTIO_MSI_NO_VECTOR) + enable_irq(pci_irq_vector(vp_dev->pci_dev, info->msix_vector)); + + vq->reset = false; + + return 0; +} + static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) { return vp_modern_config_vector(&vp_dev->mdev, vector); @@ -407,6 +487,8 @@ static const struct virtio_config_ops virtio_pci_config_nodev_ops = { .set_vq_affinity = vp_set_vq_affinity, .get_vq_affinity = vp_get_vq_affinity, .get_shm_region = vp_get_shm_region, + .reset_vq = vp_modern_reset_vq, + .enable_reset_vq = vp_modern_enable_reset_vq, }; static const struct virtio_config_ops virtio_pci_config_ops = { @@ -425,6 +507,8 @@ static const struct virtio_config_ops virtio_pci_config_ops = { .set_vq_affinity = vp_set_vq_affinity, .get_vq_affinity = vp_get_vq_affinity, .get_shm_region = vp_get_shm_region, + .reset_vq = vp_modern_reset_vq, + .enable_reset_vq = vp_modern_enable_reset_vq, }; /* the PCI probing function */ diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 6250e19fc5bf..91937e21edca 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -2028,6 +2028,7 @@ static struct virtqueue *vring_create_virtqueue_packed( vq->vq.vdev = vdev; vq->vq.name = name; vq->vq.index = index; + vq->vq.reset = false; vq->notify = notify; vq->weak_barriers = weak_barriers; @@ -2508,6 +2509,7 @@ struct virtqueue *__vring_new_virtqueue(unsigned int index, vq->vq.vdev = vdev; vq->vq.name = name; vq->vq.index = index; + vq->vq.reset = false; vq->notify = notify; vq->weak_barriers = weak_barriers; diff --git a/include/linux/virtio.h b/include/linux/virtio.h index c86ff02e0ca0..33ab003c5100 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -33,6 +33,7 @@ struct virtqueue { unsigned int num_free; unsigned int num_max; void *priv; + bool reset; }; int virtqueue_add_outbuf(struct virtqueue *vq,
This patch implements virtio pci support for QUEUE RESET. Performing reset on a queue is divided into these steps: 1. notify the device to reset the queue 2. recycle the buffer submitted 3. reset the vring (may re-alloc) 4. mmap vring to device, and enable the queue This patch implements virtio_reset_vq(), virtio_enable_resetq() in the pci scenario. Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> --- drivers/virtio/virtio_pci_common.c | 8 +-- drivers/virtio/virtio_pci_modern.c | 84 ++++++++++++++++++++++++++++++ drivers/virtio/virtio_ring.c | 2 + include/linux/virtio.h | 1 + 4 files changed, 92 insertions(+), 3 deletions(-)