| Message ID | 20220629065656.54420-31-xuanzhuo@linux.alibaba.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | virtio pci support VIRTIO_F_RING_RESET | expand |
在 2022/6/29 14:56, 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 | 12 +++- > drivers/virtio/virtio_pci_modern.c | 96 ++++++++++++++++++++++++++++++ > drivers/virtio/virtio_ring.c | 2 + > include/linux/virtio.h | 1 + > 4 files changed, 108 insertions(+), 3 deletions(-) > > diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c > index ca51fcc9daab..ad258a9d3b9f 100644 > --- a/drivers/virtio/virtio_pci_common.c > +++ b/drivers/virtio/virtio_pci_common.c > @@ -214,9 +214,15 @@ 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 it fails during re-enable reset vq. This way we won't rejoin > + * info->node to the queue. Prevent unexpected irqs. > + */ > + 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 9041d9a41b7d..754e5e10386b 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 +202,95 @@ 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 synchronize_irq(), and > + * break it. > + * > + * We can't use disable_irq() since it conflicts with the affinity > + * managed IRQ that is used by some drivers. So this is done on top of > + * IRQ hardening. > + * > + * 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) { > +#ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION > + __virtqueue_break(vq); > +#endif > + synchronize_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]; > + > + if (vp_modern_get_queue_reset(mdev, index)) > + return -EBUSY; > + > + if (vp_modern_get_queue_enable(mdev, index)) > + 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); > + } > + > +#ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION > + if (vp_dev->per_vq_vectors && info->msix_vector != VIRTIO_MSI_NO_VECTOR) > + __virtqueue_unbreak(vq); > +#endif > + > + vp_modern_set_queue_enable(&vp_dev->mdev, index, true); > + 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); > @@ -413,6 +505,8 @@ 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 = { > @@ -431,6 +525,8 @@ 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 7b02be7fce67..82b058e8ce34 100644 > --- a/drivers/virtio/virtio_ring.c > +++ b/drivers/virtio/virtio_ring.c > @@ -2008,6 +2008,7 @@ static struct virtqueue *vring_create_virtqueue_packed( > vq->vq.vdev = vdev; > vq->vq.name = name; > vq->vq.index = index; > + vq->vq.reset = false; > vq->we_own_ring = true; > vq->notify = notify; > vq->weak_barriers = weak_barriers; > @@ -2487,6 +2488,7 @@ 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->we_own_ring = false; > vq->notify = notify; > vq->weak_barriers = weak_barriers; > diff --git a/include/linux/virtio.h b/include/linux/virtio.h > index dc474a0d48d1..88f21796b1c3 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; > }; I wonder if it's better to move virtio_ring part into a separate patch. Other looks good. Thanks > > int virtqueue_add_outbuf(struct virtqueue *vq,
diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c index ca51fcc9daab..ad258a9d3b9f 100644 --- a/drivers/virtio/virtio_pci_common.c +++ b/drivers/virtio/virtio_pci_common.c @@ -214,9 +214,15 @@ 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 it fails during re-enable reset vq. This way we won't rejoin + * info->node to the queue. Prevent unexpected irqs. + */ + 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 9041d9a41b7d..754e5e10386b 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 +202,95 @@ 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 synchronize_irq(), and + * break it. + * + * We can't use disable_irq() since it conflicts with the affinity + * managed IRQ that is used by some drivers. So this is done on top of + * IRQ hardening. + * + * 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) { +#ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION + __virtqueue_break(vq); +#endif + synchronize_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]; + + if (vp_modern_get_queue_reset(mdev, index)) + return -EBUSY; + + if (vp_modern_get_queue_enable(mdev, index)) + 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); + } + +#ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION + if (vp_dev->per_vq_vectors && info->msix_vector != VIRTIO_MSI_NO_VECTOR) + __virtqueue_unbreak(vq); +#endif + + vp_modern_set_queue_enable(&vp_dev->mdev, index, true); + 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); @@ -413,6 +505,8 @@ 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 = { @@ -431,6 +525,8 @@ 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 7b02be7fce67..82b058e8ce34 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -2008,6 +2008,7 @@ static struct virtqueue *vring_create_virtqueue_packed( vq->vq.vdev = vdev; vq->vq.name = name; vq->vq.index = index; + vq->vq.reset = false; vq->we_own_ring = true; vq->notify = notify; vq->weak_barriers = weak_barriers; @@ -2487,6 +2488,7 @@ 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->we_own_ring = false; vq->notify = notify; vq->weak_barriers = weak_barriers; diff --git a/include/linux/virtio.h b/include/linux/virtio.h index dc474a0d48d1..88f21796b1c3 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 | 12 +++- drivers/virtio/virtio_pci_modern.c | 96 ++++++++++++++++++++++++++++++ drivers/virtio/virtio_ring.c | 2 + include/linux/virtio.h | 1 + 4 files changed, 108 insertions(+), 3 deletions(-)