Xuan Zhuo
2022-Feb-14 08:14 UTC
[PATCH v5 14/22] virtio_pci: queue_reset: support VIRTIO_F_RING_RESET
This patch implements virtio pci support for QUEUE RESET.
Performing reset on a queue is divided into these steps:
1. reset_vq: reset one vq
2. recycle the buffer from vq by virtqueue_detach_unused_buf()
3. release the ring of the vq by vring_release_virtqueue()
4. enable_reset_vq: re-enable the reset queue
This patch implements reset_vq, enable_reset_vq in the pci scenario.
Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com>
---
drivers/virtio/virtio_pci_common.c | 8 ++--
drivers/virtio/virtio_pci_modern.c | 60 ++++++++++++++++++++++++++++++
2 files changed, 65 insertions(+), 3 deletions(-)
diff --git a/drivers/virtio/virtio_pci_common.c
b/drivers/virtio/virtio_pci_common.c
index 5a4f750a0b97..9ea319b1d404 100644
--- a/drivers/virtio/virtio_pci_common.c
+++ b/drivers/virtio/virtio_pci_common.c
@@ -255,9 +255,11 @@ 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 bed3e9b84272..7d28f4c36fc2 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 */
@@ -176,6 +179,59 @@ static void vp_reset(struct virtio_device *vdev)
vp_disable_cbs(vdev);
}
+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);
+
+ vq->reset = VIRTQUEUE_RESET_STAGE_DEVICE;
+
+ 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;
+ struct virtqueue *_vq;
+
+ if (vq->reset != VIRTQUEUE_RESET_STAGE_RELEASE)
+ return -EBUSY;
+
+ /* check queue reset status */
+ if (vp_modern_get_queue_reset(mdev, vq->index) != 1)
+ return -EBUSY;
+
+ info = vp_dev->vqs[vq->index];
+ _vq = vp_setup_vq(vq->vdev, vq->index, NULL, NULL, NULL,
+ info->msix_vector);
+ if (IS_ERR(_vq)) {
+ vq->reset = VIRTQUEUE_RESET_STAGE_RELEASE;
+ return PTR_ERR(_vq);
+ }
+
+ vp_modern_set_queue_enable(&vp_dev->mdev, vq->index, true);
+
+ return 0;
+}
+
static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector)
{
return vp_modern_config_vector(&vp_dev->mdev, vector);
@@ -397,6 +453,8 @@ 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 = {
@@ -415,6 +473,8 @@ 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 */
--
2.31.0
Jason Wang
2022-Feb-16 04:14 UTC
[PATCH v5 14/22] virtio_pci: queue_reset: support VIRTIO_F_RING_RESET
On Mon, Feb 14, 2022 at 4:14 PM Xuan Zhuo <xuanzhuo at linux.alibaba.com> wrote:> > This patch implements virtio pci support for QUEUE RESET. > > Performing reset on a queue is divided into these steps: > > 1. reset_vq: reset one vq > 2. recycle the buffer from vq by virtqueue_detach_unused_buf() > 3. release the ring of the vq by vring_release_virtqueue() > 4. enable_reset_vq: re-enable the reset queue > > This patch implements reset_vq, enable_reset_vq in the pci scenario. > > Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com> > --- > drivers/virtio/virtio_pci_common.c | 8 ++-- > drivers/virtio/virtio_pci_modern.c | 60 ++++++++++++++++++++++++++++++ > 2 files changed, 65 insertions(+), 3 deletions(-) > > diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c > index 5a4f750a0b97..9ea319b1d404 100644 > --- a/drivers/virtio/virtio_pci_common.c > +++ b/drivers/virtio/virtio_pci_common.c > @@ -255,9 +255,11 @@ 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 bed3e9b84272..7d28f4c36fc2 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 */ > @@ -176,6 +179,59 @@ static void vp_reset(struct virtio_device *vdev) > vp_disable_cbs(vdev); > } > > +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]; > +Any reason that we don't need to disable irq here as the previous versions did?> + /* 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); > + > + vq->reset = VIRTQUEUE_RESET_STAGE_DEVICE; > + > + 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; > + struct virtqueue *_vq; > + > + if (vq->reset != VIRTQUEUE_RESET_STAGE_RELEASE) > + return -EBUSY; > + > + /* check queue reset status */ > + if (vp_modern_get_queue_reset(mdev, vq->index) != 1) > + return -EBUSY; > + > + info = vp_dev->vqs[vq->index]; > + _vq = vp_setup_vq(vq->vdev, vq->index, NULL, NULL, NULL, > + info->msix_vector);So we only care about moden devices, this means using vp_setup_vq() with NULL seems tricky. As replied in another thread, I would simply ask the caller to call the vring reallocation helper. See the reply for patch 17. Thanks> + if (IS_ERR(_vq)) { > + vq->reset = VIRTQUEUE_RESET_STAGE_RELEASE; > + return PTR_ERR(_vq); > + } > + > + vp_modern_set_queue_enable(&vp_dev->mdev, vq->index, true); > + > + return 0; > +} > + > static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) > { > return vp_modern_config_vector(&vp_dev->mdev, vector); > @@ -397,6 +453,8 @@ 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 = { > @@ -415,6 +473,8 @@ 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 */ > -- > 2.31.0 >