| Message ID | 20220126073533.44994-14-xuanzhuo@linux.alibaba.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | virtio pci support VIRTIO_F_RING_RESET | expand |
在 2022/1/26 下午3:35, Xuan Zhuo 写道: > This patch implements virtio pci support for QUEUE RESET. > > Performing reset on a queue is divided into two steps: > > 1. reset_vq: reset one vq > 2. enable_reset_vq: re-enable the reset queue > > In the first step, these tasks will be completed: > 1. notify the hardware queue to reset > 2. recycle the buffer from vq > 3. release the ring of the vq > > The process of enable reset vq: > vp_modern_enable_reset_vq() > vp_enable_reset_vq() > __vp_setup_vq() > setup_vq() > vring_setup_virtqueue() > > In this process, we added two parameters, vq and num, and finally passed > them to vring_setup_virtqueue(). And reuse the original info and vq. > > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > --- > drivers/virtio/virtio_pci_common.c | 36 +++++++---- > drivers/virtio/virtio_pci_common.h | 5 ++ > drivers/virtio/virtio_pci_modern.c | 100 +++++++++++++++++++++++++++++ > 3 files changed, 128 insertions(+), 13 deletions(-) > > diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c > index c02936d29a31..ad21638fbf66 100644 > --- a/drivers/virtio/virtio_pci_common.c > +++ b/drivers/virtio/virtio_pci_common.c > @@ -205,23 +205,28 @@ static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors, > return err; > } > > -static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, > - void (*callback)(struct virtqueue *vq), > - const char *name, > - bool ctx, > - u16 msix_vec, u16 num) > +struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, > + void (*callback)(struct virtqueue *vq), > + const char *name, > + bool ctx, > + u16 msix_vec, u16 num) > { > struct virtio_pci_device *vp_dev = to_vp_device(vdev); > - struct virtio_pci_vq_info *info = kmalloc(sizeof *info, GFP_KERNEL); > + struct virtio_pci_vq_info *info; > struct virtqueue *vq; > unsigned long flags; > > - /* fill out our structure that represents an active queue */ > - if (!info) > - return ERR_PTR(-ENOMEM); > + info = vp_dev->vqs[index]; > + if (!info) { > + info = kzalloc(sizeof *info, GFP_KERNEL); > + > + /* fill out our structure that represents an active queue */ > + if (!info) > + return ERR_PTR(-ENOMEM); > + } > > vq = vp_dev->setup_vq(vp_dev, info, index, callback, name, ctx, > - msix_vec, NULL, num); > + msix_vec, info->vq, num); > if (IS_ERR(vq)) > goto out_info; > > @@ -238,6 +243,9 @@ static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, > return vq; > > out_info: > + if (info->vq && info->vq->reset) > + return vq; > + > kfree(info); > return vq; > } > @@ -248,9 +256,11 @@ 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_common.h b/drivers/virtio/virtio_pci_common.h > index 65db92245e41..c1d15f7c0be4 100644 > --- a/drivers/virtio/virtio_pci_common.h > +++ b/drivers/virtio/virtio_pci_common.h > @@ -119,6 +119,11 @@ int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs, > struct virtqueue *vqs[], vq_callback_t *callbacks[], > const char * const names[], const bool *ctx, > struct irq_affinity *desc); > +struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, > + void (*callback)(struct virtqueue *vq), > + const char *name, > + bool ctx, > + u16 msix_vec, u16 num); > const char *vp_bus_name(struct virtio_device *vdev); > > /* Setup the affinity for a virtqueue: > diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c > index 2ce58de549de..6789411169e4 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 +179,94 @@ static void vp_reset(struct virtio_device *vdev) > vp_disable_cbs(vdev); > } > > +static int vp_modern_reset_vq(struct virtio_reset_vq *param) > +{ > + struct virtio_pci_device *vp_dev = to_vp_device(param->vdev); > + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > + struct virtio_pci_vq_info *info; > + u16 msix_vec, queue_index; > + unsigned long flags; > + void *buf; > + > + if (!virtio_has_feature(param->vdev, VIRTIO_F_RING_RESET)) > + return -ENOENT; > + > + queue_index = param->queue_index; > + > + vp_modern_set_queue_reset(mdev, queue_index); > + > + /* After write 1 to queue reset, the driver MUST wait for a read of > + * queue reset to return 1. > + */ > + while (vp_modern_get_queue_reset(mdev, queue_index) != 1) > + msleep(1); Is this better to move this logic into vp_modern_set_queue_reset()? > + > + info = vp_dev->vqs[queue_index]; > + msix_vec = info->msix_vector; > + > + /* Disable VQ callback. */ > + if (vp_dev->per_vq_vectors && msix_vec != VIRTIO_MSI_NO_VECTOR) > + disable_irq(pci_irq_vector(vp_dev->pci_dev, msix_vec)); How about the INTX case where irq is shared? I guess we need to disable and enable the irq as well. > + > + while ((buf = virtqueue_detach_unused_buf(info->vq)) != NULL) > + param->free_unused_cb(param, buf); Any reason that we can't leave this logic to driver? (Or is there any operations that must be done before the following operations?) > + > + /* delete vq */ > + spin_lock_irqsave(&vp_dev->lock, flags); > + list_del(&info->node); > + spin_unlock_irqrestore(&vp_dev->lock, flags); > + > + INIT_LIST_HEAD(&info->node); > + > + if (vp_dev->msix_enabled) > + vp_modern_queue_vector(mdev, info->vq->index, > + VIRTIO_MSI_NO_VECTOR); I wonder if this is a must. > + > + if (!mdev->notify_base) > + pci_iounmap(mdev->pci_dev, > + (void __force __iomem *)info->vq->priv); Is this a must? what happens if we simply don't do this? > + > + vring_reset_virtqueue(info->vq); > + > + return 0; > +} > + > +static struct virtqueue *vp_modern_enable_reset_vq(struct virtio_reset_vq *param) > +{ > + struct virtio_pci_device *vp_dev = to_vp_device(param->vdev); > + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > + struct virtio_pci_vq_info *info; > + u16 msix_vec, queue_index; > + struct virtqueue *vq; > + > + if (!virtio_has_feature(param->vdev, VIRTIO_F_RING_RESET)) > + return ERR_PTR(-ENOENT); > + > + queue_index = param->queue_index; > + > + info = vp_dev->vqs[queue_index]; > + > + if (!info->vq->reset) > + return ERR_PTR(-EPERM); > + > + /* check queue reset status */ > + if (vp_modern_get_queue_reset(mdev, queue_index) != 1) > + return ERR_PTR(-EBUSY); > + > + vq = vp_setup_vq(param->vdev, queue_index, param->callback, param->name, > + param->ctx, info->msix_vector, param->ring_num); > + if (IS_ERR(vq)) > + return vq; > + > + vp_modern_set_queue_enable(&vp_dev->mdev, vq->index, true); > + > + msix_vec = vp_dev->vqs[queue_index]->msix_vector; > + if (vp_dev->per_vq_vectors && msix_vec != VIRTIO_MSI_NO_VECTOR) > + enable_irq(pci_irq_vector(vp_dev->pci_dev, msix_vec)); How about the INT-X case? Thanks > + > + return vq; > +} > + > static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) > { > return vp_modern_config_vector(&vp_dev->mdev, vector); > @@ -284,6 +375,11 @@ static void del_vq(struct virtio_pci_vq_info *info) > struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); > struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > > + if (vq->reset) { > + vring_del_virtqueue(vq); > + return; > + } > + > if (vp_dev->msix_enabled) > vp_modern_queue_vector(mdev, vq->index, > VIRTIO_MSI_NO_VECTOR); > @@ -403,6 +499,8 @@ 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 = { > @@ -421,6 +519,8 @@ 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 */
On Mon, Feb 7, 2022 at 4:19 PM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote: > > On Mon, 7 Feb 2022 14:57:13 +0800, Jason Wang <jasowang@redhat.com> wrote: > > > > 在 2022/1/26 下午3:35, Xuan Zhuo 写道: > > > This patch implements virtio pci support for QUEUE RESET. > > > > > > Performing reset on a queue is divided into two steps: > > > > > > 1. reset_vq: reset one vq > > > 2. enable_reset_vq: re-enable the reset queue > > > > > > In the first step, these tasks will be completed: > > > 1. notify the hardware queue to reset > > > 2. recycle the buffer from vq > > > 3. release the ring of the vq > > > > > > The process of enable reset vq: > > > vp_modern_enable_reset_vq() > > > vp_enable_reset_vq() > > > __vp_setup_vq() > > > setup_vq() > > > vring_setup_virtqueue() > > > > > > In this process, we added two parameters, vq and num, and finally passed > > > them to vring_setup_virtqueue(). And reuse the original info and vq. > > > > > > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > > > --- > > > drivers/virtio/virtio_pci_common.c | 36 +++++++---- > > > drivers/virtio/virtio_pci_common.h | 5 ++ > > > drivers/virtio/virtio_pci_modern.c | 100 +++++++++++++++++++++++++++++ > > > 3 files changed, 128 insertions(+), 13 deletions(-) > > > > > > diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c > > > index c02936d29a31..ad21638fbf66 100644 > > > --- a/drivers/virtio/virtio_pci_common.c > > > +++ b/drivers/virtio/virtio_pci_common.c > > > @@ -205,23 +205,28 @@ static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors, > > > return err; > > > } > > > > > > -static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, > > > - void (*callback)(struct virtqueue *vq), > > > - const char *name, > > > - bool ctx, > > > - u16 msix_vec, u16 num) > > > +struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, > > > + void (*callback)(struct virtqueue *vq), > > > + const char *name, > > > + bool ctx, > > > + u16 msix_vec, u16 num) > > > { > > > struct virtio_pci_device *vp_dev = to_vp_device(vdev); > > > - struct virtio_pci_vq_info *info = kmalloc(sizeof *info, GFP_KERNEL); > > > + struct virtio_pci_vq_info *info; > > > struct virtqueue *vq; > > > unsigned long flags; > > > > > > - /* fill out our structure that represents an active queue */ > > > - if (!info) > > > - return ERR_PTR(-ENOMEM); > > > + info = vp_dev->vqs[index]; > > > + if (!info) { > > > + info = kzalloc(sizeof *info, GFP_KERNEL); > > > + > > > + /* fill out our structure that represents an active queue */ > > > + if (!info) > > > + return ERR_PTR(-ENOMEM); > > > + } > > > > > > vq = vp_dev->setup_vq(vp_dev, info, index, callback, name, ctx, > > > - msix_vec, NULL, num); > > > + msix_vec, info->vq, num); > > > if (IS_ERR(vq)) > > > goto out_info; > > > > > > @@ -238,6 +243,9 @@ static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, > > > return vq; > > > > > > out_info: > > > + if (info->vq && info->vq->reset) > > > + return vq; > > > + > > > kfree(info); > > > return vq; > > > } > > > @@ -248,9 +256,11 @@ 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_common.h b/drivers/virtio/virtio_pci_common.h > > > index 65db92245e41..c1d15f7c0be4 100644 > > > --- a/drivers/virtio/virtio_pci_common.h > > > +++ b/drivers/virtio/virtio_pci_common.h > > > @@ -119,6 +119,11 @@ int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs, > > > struct virtqueue *vqs[], vq_callback_t *callbacks[], > > > const char * const names[], const bool *ctx, > > > struct irq_affinity *desc); > > > +struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, > > > + void (*callback)(struct virtqueue *vq), > > > + const char *name, > > > + bool ctx, > > > + u16 msix_vec, u16 num); > > > const char *vp_bus_name(struct virtio_device *vdev); > > > > > > /* Setup the affinity for a virtqueue: > > > diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c > > > index 2ce58de549de..6789411169e4 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 +179,94 @@ static void vp_reset(struct virtio_device *vdev) > > > vp_disable_cbs(vdev); > > > } > > > > > > +static int vp_modern_reset_vq(struct virtio_reset_vq *param) > > > +{ > > > + struct virtio_pci_device *vp_dev = to_vp_device(param->vdev); > > > + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > > > + struct virtio_pci_vq_info *info; > > > + u16 msix_vec, queue_index; > > > + unsigned long flags; > > > + void *buf; > > > + > > > + if (!virtio_has_feature(param->vdev, VIRTIO_F_RING_RESET)) > > > + return -ENOENT; > > > + > > > + queue_index = param->queue_index; > > > + > > > + vp_modern_set_queue_reset(mdev, queue_index); > > > + > > > + /* After write 1 to queue reset, the driver MUST wait for a read of > > > + * queue reset to return 1. > > > + */ > > > + while (vp_modern_get_queue_reset(mdev, queue_index) != 1) > > > + msleep(1); > > > > > > Is this better to move this logic into vp_modern_set_queue_reset()? > > > > OK. > > > > > > + > > > + info = vp_dev->vqs[queue_index]; > > > + msix_vec = info->msix_vector; > > > + > > > + /* Disable VQ callback. */ > > > + if (vp_dev->per_vq_vectors && msix_vec != VIRTIO_MSI_NO_VECTOR) > > > + disable_irq(pci_irq_vector(vp_dev->pci_dev, msix_vec)); > > > > > > How about the INTX case where irq is shared? I guess we need to disable > > and enable the irq as well. > > For the INTX scenario, I don't think we need to disable/enable the irq. But I do > have a mistake, I should put the following list_del(&info->node) here, so that > when the irq comes, it will no longer operate this vq. > > In fact, for no INTX case, the disable_irq here is not necessary, according to > the requirements of the spec, after reset, the device should not generate irq > anymore. I may miss something but I don't think INTX differs from MSI from the vq handler perspective. > Here just to prevent accidents. The problem is that if you don't disable/sync IRQ there could be a race between the vq irq handler and the virtqueue_detach_unused_buf()? > > > > > > > > + > > > + while ((buf = virtqueue_detach_unused_buf(info->vq)) != NULL) > > > + param->free_unused_cb(param, buf); > > > > > > Any reason that we can't leave this logic to driver? (Or is there any > > operations that must be done before the following operations?) > > As you commented before, we merged free unused buf and reset queue. > > I think it's a good note, otherwise, we're going to > > 1. reset vq > 2. free unused(by driver) > 3. free ring of vq Rethink about this, I'd prefer to leave it to the driver for consistency. E.g the virtqueue_detach_unused_buf() is called by each driver nowdays. > > > > > > > > > + > > > + /* delete vq */ > > > + spin_lock_irqsave(&vp_dev->lock, flags); > > > + list_del(&info->node); > > > + spin_unlock_irqrestore(&vp_dev->lock, flags); > > > + > > > + INIT_LIST_HEAD(&info->node); > > > + > > > + if (vp_dev->msix_enabled) > > > + vp_modern_queue_vector(mdev, info->vq->index, > > > + VIRTIO_MSI_NO_VECTOR); > > > > > > I wonder if this is a must. > > > > > > > + > > > + if (!mdev->notify_base) > > > + pci_iounmap(mdev->pci_dev, > > > + (void __force __iomem *)info->vq->priv); > > > > > > Is this a must? what happens if we simply don't do this? > > > > The purpose of these two operations is mainly to be symmetrical with del_vq(). This is another question I want to ask. Any reason for calling del_vq()? Is it because you need to exclude a vq from the vq handler? For any case, the MSI and notification stuff seems unnecessary. Thanks > > > > > > > + > > > + vring_reset_virtqueue(info->vq); > > > + > > > + return 0; > > > +} > > > + > > > +static struct virtqueue *vp_modern_enable_reset_vq(struct virtio_reset_vq *param) > > > +{ > > > + struct virtio_pci_device *vp_dev = to_vp_device(param->vdev); > > > + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > > > + struct virtio_pci_vq_info *info; > > > + u16 msix_vec, queue_index; > > > + struct virtqueue *vq; > > > + > > > + if (!virtio_has_feature(param->vdev, VIRTIO_F_RING_RESET)) > > > + return ERR_PTR(-ENOENT); > > > + > > > + queue_index = param->queue_index; > > > + > > > + info = vp_dev->vqs[queue_index]; > > > + > > > + if (!info->vq->reset) > > > + return ERR_PTR(-EPERM); > > > + > > > + /* check queue reset status */ > > > + if (vp_modern_get_queue_reset(mdev, queue_index) != 1) > > > + return ERR_PTR(-EBUSY); > > > + > > > + vq = vp_setup_vq(param->vdev, queue_index, param->callback, param->name, > > > + param->ctx, info->msix_vector, param->ring_num); > > > + if (IS_ERR(vq)) > > > + return vq; > > > + > > > + vp_modern_set_queue_enable(&vp_dev->mdev, vq->index, true); > > > + > > > + msix_vec = vp_dev->vqs[queue_index]->msix_vector; > > > + if (vp_dev->per_vq_vectors && msix_vec != VIRTIO_MSI_NO_VECTOR) > > > + enable_irq(pci_irq_vector(vp_dev->pci_dev, msix_vec)); > > > > > > How about the INT-X case? > > Explained above. > > Thanks. > > > > > Thanks > > > > > > > + > > > + return vq; > > > +} > > > + > > > static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) > > > { > > > return vp_modern_config_vector(&vp_dev->mdev, vector); > > > @@ -284,6 +375,11 @@ static void del_vq(struct virtio_pci_vq_info *info) > > > struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); > > > struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > > > > > > + if (vq->reset) { > > > + vring_del_virtqueue(vq); > > > + return; > > > + } > > > + > > > if (vp_dev->msix_enabled) > > > vp_modern_queue_vector(mdev, vq->index, > > > VIRTIO_MSI_NO_VECTOR); > > > @@ -403,6 +499,8 @@ 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 = { > > > @@ -421,6 +519,8 @@ 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 */ > > >
On 2022/2/8 上午10:55, Jason Wang wrote: > On Mon, Feb 7, 2022 at 4:19 PM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote: >> On Mon, 7 Feb 2022 14:57:13 +0800, Jason Wang <jasowang@redhat.com> wrote: >>> 在 2022/1/26 下午3:35, Xuan Zhuo 写道: >>>> This patch implements virtio pci support for QUEUE RESET. >>>> >>>> Performing reset on a queue is divided into two steps: >>>> >>>> 1. reset_vq: reset one vq >>>> 2. enable_reset_vq: re-enable the reset queue >>>> >>>> In the first step, these tasks will be completed: >>>> 1. notify the hardware queue to reset >>>> 2. recycle the buffer from vq >>>> 3. release the ring of the vq >>>> >>>> The process of enable reset vq: >>>> vp_modern_enable_reset_vq() >>>> vp_enable_reset_vq() >>>> __vp_setup_vq() >>>> setup_vq() >>>> vring_setup_virtqueue() >>>> >>>> In this process, we added two parameters, vq and num, and finally passed >>>> them to vring_setup_virtqueue(). And reuse the original info and vq. >>>> >>>> Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> >>>> --- >>>> drivers/virtio/virtio_pci_common.c | 36 +++++++---- >>>> drivers/virtio/virtio_pci_common.h | 5 ++ >>>> drivers/virtio/virtio_pci_modern.c | 100 +++++++++++++++++++++++++++++ >>>> 3 files changed, 128 insertions(+), 13 deletions(-) >>>> >>>> diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c >>>> index c02936d29a31..ad21638fbf66 100644 >>>> --- a/drivers/virtio/virtio_pci_common.c >>>> +++ b/drivers/virtio/virtio_pci_common.c >>>> @@ -205,23 +205,28 @@ static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors, >>>> return err; >>>> } >>>> >>>> -static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, >>>> - void (*callback)(struct virtqueue *vq), >>>> - const char *name, >>>> - bool ctx, >>>> - u16 msix_vec, u16 num) >>>> +struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, >>>> + void (*callback)(struct virtqueue *vq), >>>> + const char *name, >>>> + bool ctx, >>>> + u16 msix_vec, u16 num) >>>> { >>>> struct virtio_pci_device *vp_dev = to_vp_device(vdev); >>>> - struct virtio_pci_vq_info *info = kmalloc(sizeof *info, GFP_KERNEL); >>>> + struct virtio_pci_vq_info *info; >>>> struct virtqueue *vq; >>>> unsigned long flags; >>>> >>>> - /* fill out our structure that represents an active queue */ >>>> - if (!info) >>>> - return ERR_PTR(-ENOMEM); >>>> + info = vp_dev->vqs[index]; >>>> + if (!info) { >>>> + info = kzalloc(sizeof *info, GFP_KERNEL); >>>> + >>>> + /* fill out our structure that represents an active queue */ >>>> + if (!info) >>>> + return ERR_PTR(-ENOMEM); >>>> + } >>>> >>>> vq = vp_dev->setup_vq(vp_dev, info, index, callback, name, ctx, >>>> - msix_vec, NULL, num); >>>> + msix_vec, info->vq, num); >>>> if (IS_ERR(vq)) >>>> goto out_info; >>>> >>>> @@ -238,6 +243,9 @@ static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, >>>> return vq; >>>> >>>> out_info: >>>> + if (info->vq && info->vq->reset) >>>> + return vq; >>>> + >>>> kfree(info); >>>> return vq; >>>> } >>>> @@ -248,9 +256,11 @@ 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_common.h b/drivers/virtio/virtio_pci_common.h >>>> index 65db92245e41..c1d15f7c0be4 100644 >>>> --- a/drivers/virtio/virtio_pci_common.h >>>> +++ b/drivers/virtio/virtio_pci_common.h >>>> @@ -119,6 +119,11 @@ int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs, >>>> struct virtqueue *vqs[], vq_callback_t *callbacks[], >>>> const char * const names[], const bool *ctx, >>>> struct irq_affinity *desc); >>>> +struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, >>>> + void (*callback)(struct virtqueue *vq), >>>> + const char *name, >>>> + bool ctx, >>>> + u16 msix_vec, u16 num); >>>> const char *vp_bus_name(struct virtio_device *vdev); >>>> >>>> /* Setup the affinity for a virtqueue: >>>> diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c >>>> index 2ce58de549de..6789411169e4 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 +179,94 @@ static void vp_reset(struct virtio_device *vdev) >>>> vp_disable_cbs(vdev); >>>> } >>>> >>>> +static int vp_modern_reset_vq(struct virtio_reset_vq *param) >>>> +{ >>>> + struct virtio_pci_device *vp_dev = to_vp_device(param->vdev); >>>> + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; >>>> + struct virtio_pci_vq_info *info; >>>> + u16 msix_vec, queue_index; >>>> + unsigned long flags; >>>> + void *buf; >>>> + >>>> + if (!virtio_has_feature(param->vdev, VIRTIO_F_RING_RESET)) >>>> + return -ENOENT; >>>> + >>>> + queue_index = param->queue_index; >>>> + >>>> + vp_modern_set_queue_reset(mdev, queue_index); >>>> + >>>> + /* After write 1 to queue reset, the driver MUST wait for a read of >>>> + * queue reset to return 1. >>>> + */ >>>> + while (vp_modern_get_queue_reset(mdev, queue_index) != 1) >>>> + msleep(1); >>> >>> Is this better to move this logic into vp_modern_set_queue_reset()? >>> >> OK. >> >>>> + >>>> + info = vp_dev->vqs[queue_index]; >>>> + msix_vec = info->msix_vector; >>>> + >>>> + /* Disable VQ callback. */ >>>> + if (vp_dev->per_vq_vectors && msix_vec != VIRTIO_MSI_NO_VECTOR) >>>> + disable_irq(pci_irq_vector(vp_dev->pci_dev, msix_vec)); >>> >>> How about the INTX case where irq is shared? I guess we need to disable >>> and enable the irq as well. >> For the INTX scenario, I don't think we need to disable/enable the irq. But I do >> have a mistake, I should put the following list_del(&info->node) here, so that >> when the irq comes, it will no longer operate this vq. >> >> In fact, for no INTX case, the disable_irq here is not necessary, according to >> the requirements of the spec, after reset, the device should not generate irq >> anymore. > I may miss something but I don't think INTX differs from MSI from the > vq handler perspective. > >> Here just to prevent accidents. > The problem is that if you don't disable/sync IRQ there could be a > race between the vq irq handler and the virtqueue_detach_unused_buf()? I understand that under INTX, the irq handler (vp_vring_interrupt) will check the list vp_dev->virtqueues to call the vq callback. Then if we have deleted it from vp_dev->virtqueues, then there is no need to disable irq. And this process is locked by vp_dev->lock. >>> >>>> + >>>> + while ((buf = virtqueue_detach_unused_buf(info->vq)) != NULL) >>>> + param->free_unused_cb(param, buf); >>> >>> Any reason that we can't leave this logic to driver? (Or is there any >>> operations that must be done before the following operations?) >> As you commented before, we merged free unused buf and reset queue. >> >> I think it's a good note, otherwise, we're going to >> >> 1. reset vq >> 2. free unused(by driver) >> 3. free ring of vq > Rethink about this, I'd prefer to leave it to the driver for consistency. > > E.g the virtqueue_detach_unused_buf() is called by each driver nowdays. > OK >> >>> >>>> + >>>> + /* delete vq */ >>>> + spin_lock_irqsave(&vp_dev->lock, flags); >>>> + list_del(&info->node); >>>> + spin_unlock_irqrestore(&vp_dev->lock, flags); >>>> + >>>> + INIT_LIST_HEAD(&info->node); >>>> + >>>> + if (vp_dev->msix_enabled) >>>> + vp_modern_queue_vector(mdev, info->vq->index, >>>> + VIRTIO_MSI_NO_VECTOR); >>> >>> I wonder if this is a must. >>> >>> >>>> + >>>> + if (!mdev->notify_base) >>>> + pci_iounmap(mdev->pci_dev, >>>> + (void __force __iomem *)info->vq->priv); >>> >>> Is this a must? what happens if we simply don't do this? >>> >> The purpose of these two operations is mainly to be symmetrical with del_vq(). > This is another question I want to ask. Any reason for calling > del_vq()? Is it because you need to exclude a vq from the vq handler? I didn't actually call del_vq(), but I think the process is similar to it, so I'd like to be symmetric with del_vq() in implementation. The separation from the vq handler is achieved by the following code: spin_lock_irqsave(&vp_dev->lock, flags); list_del(&info->node); spin_unlock_irqrestore(&vp_dev->lock, flags); > For any case, the MSI and notification stuff seems unnecessary. I will remove these in next version. Thanks. > Thanks > >> >>>> + >>>> + vring_reset_virtqueue(info->vq); >>>> + >>>> + return 0; >>>> +} >>>> + >>>> +static struct virtqueue *vp_modern_enable_reset_vq(struct virtio_reset_vq *param) >>>> +{ >>>> + struct virtio_pci_device *vp_dev = to_vp_device(param->vdev); >>>> + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; >>>> + struct virtio_pci_vq_info *info; >>>> + u16 msix_vec, queue_index; >>>> + struct virtqueue *vq; >>>> + >>>> + if (!virtio_has_feature(param->vdev, VIRTIO_F_RING_RESET)) >>>> + return ERR_PTR(-ENOENT); >>>> + >>>> + queue_index = param->queue_index; >>>> + >>>> + info = vp_dev->vqs[queue_index]; >>>> + >>>> + if (!info->vq->reset) >>>> + return ERR_PTR(-EPERM); >>>> + >>>> + /* check queue reset status */ >>>> + if (vp_modern_get_queue_reset(mdev, queue_index) != 1) >>>> + return ERR_PTR(-EBUSY); >>>> + >>>> + vq = vp_setup_vq(param->vdev, queue_index, param->callback, param->name, >>>> + param->ctx, info->msix_vector, param->ring_num); >>>> + if (IS_ERR(vq)) >>>> + return vq; >>>> + >>>> + vp_modern_set_queue_enable(&vp_dev->mdev, vq->index, true); >>>> + >>>> + msix_vec = vp_dev->vqs[queue_index]->msix_vector; >>>> + if (vp_dev->per_vq_vectors && msix_vec != VIRTIO_MSI_NO_VECTOR) >>>> + enable_irq(pci_irq_vector(vp_dev->pci_dev, msix_vec)); >>> >>> How about the INT-X case? >> Explained above. >> >> Thanks. >> >>> Thanks >>> >>> >>>> + >>>> + return vq; >>>> +} >>>> + >>>> static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) >>>> { >>>> return vp_modern_config_vector(&vp_dev->mdev, vector); >>>> @@ -284,6 +375,11 @@ static void del_vq(struct virtio_pci_vq_info *info) >>>> struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); >>>> struct virtio_pci_modern_device *mdev = &vp_dev->mdev; >>>> >>>> + if (vq->reset) { >>>> + vring_del_virtqueue(vq); >>>> + return; >>>> + } >>>> + >>>> if (vp_dev->msix_enabled) >>>> vp_modern_queue_vector(mdev, vq->index, >>>> VIRTIO_MSI_NO_VECTOR); >>>> @@ -403,6 +499,8 @@ 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 = { >>>> @@ -421,6 +519,8 @@ 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 */
On Tue, Feb 8, 2022 at 3:44 PM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote: > > On Tue, 8 Feb 2022 10:55:37 +0800, Jason Wang <jasowang@redhat.com> wrote: > > On Mon, Feb 7, 2022 at 4:19 PM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote: > > > > > > On Mon, 7 Feb 2022 14:57:13 +0800, Jason Wang <jasowang@redhat.com> wrote: > > > > > > > > 在 2022/1/26 下午3:35, Xuan Zhuo 写道: > > > > > This patch implements virtio pci support for QUEUE RESET. > > > > > > > > > > Performing reset on a queue is divided into two steps: > > > > > > > > > > 1. reset_vq: reset one vq > > > > > 2. enable_reset_vq: re-enable the reset queue > > > > > > > > > > In the first step, these tasks will be completed: > > > > > 1. notify the hardware queue to reset > > > > > 2. recycle the buffer from vq > > > > > 3. release the ring of the vq > > > > > > > > > > The process of enable reset vq: > > > > > vp_modern_enable_reset_vq() > > > > > vp_enable_reset_vq() > > > > > __vp_setup_vq() > > > > > setup_vq() > > > > > vring_setup_virtqueue() > > > > > > > > > > In this process, we added two parameters, vq and num, and finally passed > > > > > them to vring_setup_virtqueue(). And reuse the original info and vq. > > > > > > > > > > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > > > > > --- > > > > > drivers/virtio/virtio_pci_common.c | 36 +++++++---- > > > > > drivers/virtio/virtio_pci_common.h | 5 ++ > > > > > drivers/virtio/virtio_pci_modern.c | 100 +++++++++++++++++++++++++++++ > > > > > 3 files changed, 128 insertions(+), 13 deletions(-) > > > > > > > > > > diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c > > > > > index c02936d29a31..ad21638fbf66 100644 > > > > > --- a/drivers/virtio/virtio_pci_common.c > > > > > +++ b/drivers/virtio/virtio_pci_common.c > > > > > @@ -205,23 +205,28 @@ static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors, > > > > > return err; > > > > > } > > > > > > > > > > -static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, > > > > > - void (*callback)(struct virtqueue *vq), > > > > > - const char *name, > > > > > - bool ctx, > > > > > - u16 msix_vec, u16 num) > > > > > +struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, > > > > > + void (*callback)(struct virtqueue *vq), > > > > > + const char *name, > > > > > + bool ctx, > > > > > + u16 msix_vec, u16 num) > > > > > { > > > > > struct virtio_pci_device *vp_dev = to_vp_device(vdev); > > > > > - struct virtio_pci_vq_info *info = kmalloc(sizeof *info, GFP_KERNEL); > > > > > + struct virtio_pci_vq_info *info; > > > > > struct virtqueue *vq; > > > > > unsigned long flags; > > > > > > > > > > - /* fill out our structure that represents an active queue */ > > > > > - if (!info) > > > > > - return ERR_PTR(-ENOMEM); > > > > > + info = vp_dev->vqs[index]; > > > > > + if (!info) { > > > > > + info = kzalloc(sizeof *info, GFP_KERNEL); > > > > > + > > > > > + /* fill out our structure that represents an active queue */ > > > > > + if (!info) > > > > > + return ERR_PTR(-ENOMEM); > > > > > + } > > > > > > > > > > vq = vp_dev->setup_vq(vp_dev, info, index, callback, name, ctx, > > > > > - msix_vec, NULL, num); > > > > > + msix_vec, info->vq, num); > > > > > if (IS_ERR(vq)) > > > > > goto out_info; > > > > > > > > > > @@ -238,6 +243,9 @@ static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, > > > > > return vq; > > > > > > > > > > out_info: > > > > > + if (info->vq && info->vq->reset) > > > > > + return vq; > > > > > + > > > > > kfree(info); > > > > > return vq; > > > > > } > > > > > @@ -248,9 +256,11 @@ 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_common.h b/drivers/virtio/virtio_pci_common.h > > > > > index 65db92245e41..c1d15f7c0be4 100644 > > > > > --- a/drivers/virtio/virtio_pci_common.h > > > > > +++ b/drivers/virtio/virtio_pci_common.h > > > > > @@ -119,6 +119,11 @@ int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs, > > > > > struct virtqueue *vqs[], vq_callback_t *callbacks[], > > > > > const char * const names[], const bool *ctx, > > > > > struct irq_affinity *desc); > > > > > +struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, > > > > > + void (*callback)(struct virtqueue *vq), > > > > > + const char *name, > > > > > + bool ctx, > > > > > + u16 msix_vec, u16 num); > > > > > const char *vp_bus_name(struct virtio_device *vdev); > > > > > > > > > > /* Setup the affinity for a virtqueue: > > > > > diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c > > > > > index 2ce58de549de..6789411169e4 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 +179,94 @@ static void vp_reset(struct virtio_device *vdev) > > > > > vp_disable_cbs(vdev); > > > > > } > > > > > > > > > > +static int vp_modern_reset_vq(struct virtio_reset_vq *param) > > > > > +{ > > > > > + struct virtio_pci_device *vp_dev = to_vp_device(param->vdev); > > > > > + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > > > > > + struct virtio_pci_vq_info *info; > > > > > + u16 msix_vec, queue_index; > > > > > + unsigned long flags; > > > > > + void *buf; > > > > > + > > > > > + if (!virtio_has_feature(param->vdev, VIRTIO_F_RING_RESET)) > > > > > + return -ENOENT; > > > > > + > > > > > + queue_index = param->queue_index; > > > > > + > > > > > + vp_modern_set_queue_reset(mdev, queue_index); > > > > > + > > > > > + /* After write 1 to queue reset, the driver MUST wait for a read of > > > > > + * queue reset to return 1. > > > > > + */ > > > > > + while (vp_modern_get_queue_reset(mdev, queue_index) != 1) > > > > > + msleep(1); > > > > > > > > > > > > Is this better to move this logic into vp_modern_set_queue_reset()? > > > > > > > > > > OK. > > > > > > > > > > > > + > > > > > + info = vp_dev->vqs[queue_index]; > > > > > + msix_vec = info->msix_vector; > > > > > + > > > > > + /* Disable VQ callback. */ > > > > > + if (vp_dev->per_vq_vectors && msix_vec != VIRTIO_MSI_NO_VECTOR) > > > > > + disable_irq(pci_irq_vector(vp_dev->pci_dev, msix_vec)); > > > > > > > > > > > > How about the INTX case where irq is shared? I guess we need to disable > > > > and enable the irq as well. > > > > > > For the INTX scenario, I don't think we need to disable/enable the irq. But I do > > > have a mistake, I should put the following list_del(&info->node) here, so that > > > when the irq comes, it will no longer operate this vq. > > > > > > In fact, for no INTX case, the disable_irq here is not necessary, according to > > > the requirements of the spec, after reset, the device should not generate irq > > > anymore. > > > > I may miss something but I don't think INTX differs from MSI from the > > vq handler perspective. > > > > > Here just to prevent accidents. > > > > The problem is that if you don't disable/sync IRQ there could be a > > race between the vq irq handler and the virtqueue_detach_unused_buf()? > > > > > > > > > > > > > > > > > > + > > > > > + while ((buf = virtqueue_detach_unused_buf(info->vq)) != NULL) > > > > > + param->free_unused_cb(param, buf); > > > > > > > > > > > > Any reason that we can't leave this logic to driver? (Or is there any > > > > operations that must be done before the following operations?) > > > > > > As you commented before, we merged free unused buf and reset queue. > > > > > > I think it's a good note, otherwise, we're going to > > > > > > 1. reset vq > > > 2. free unused(by driver) > > > 3. free ring of vq > > > > Rethink about this, I'd prefer to leave it to the driver for consistency. > > > > E.g the virtqueue_detach_unused_buf() is called by each driver nowdays. > > In this case, go back to my previous design and add three helpers: > > int (*reset_vq)(); > int (*free_reset_vq)(); So this is only needed if there are any transport specific operations. But I don't see there's any. Thanks > int (*enable_reset_vq)(); > > Thanks. > > > > > > > > > > > > > > > > > > > > > > + > > > > > + /* delete vq */ > > > > > + spin_lock_irqsave(&vp_dev->lock, flags); > > > > > + list_del(&info->node); > > > > > + spin_unlock_irqrestore(&vp_dev->lock, flags); > > > > > + > > > > > + INIT_LIST_HEAD(&info->node); > > > > > + > > > > > + if (vp_dev->msix_enabled) > > > > > + vp_modern_queue_vector(mdev, info->vq->index, > > > > > + VIRTIO_MSI_NO_VECTOR); > > > > > > > > > > > > I wonder if this is a must. > > > > > > > > > > > > > + > > > > > + if (!mdev->notify_base) > > > > > + pci_iounmap(mdev->pci_dev, > > > > > + (void __force __iomem *)info->vq->priv); > > > > > > > > > > > > Is this a must? what happens if we simply don't do this? > > > > > > > > > > The purpose of these two operations is mainly to be symmetrical with del_vq(). > > > > This is another question I want to ask. Any reason for calling > > del_vq()? Is it because you need to exclude a vq from the vq handler? > > > > For any case, the MSI and notification stuff seems unnecessary. > > > > Thanks > > > > > > > > > > > > > > > > > + > > > > > + vring_reset_virtqueue(info->vq); > > > > > + > > > > > + return 0; > > > > > +} > > > > > + > > > > > +static struct virtqueue *vp_modern_enable_reset_vq(struct virtio_reset_vq *param) > > > > > +{ > > > > > + struct virtio_pci_device *vp_dev = to_vp_device(param->vdev); > > > > > + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > > > > > + struct virtio_pci_vq_info *info; > > > > > + u16 msix_vec, queue_index; > > > > > + struct virtqueue *vq; > > > > > + > > > > > + if (!virtio_has_feature(param->vdev, VIRTIO_F_RING_RESET)) > > > > > + return ERR_PTR(-ENOENT); > > > > > + > > > > > + queue_index = param->queue_index; > > > > > + > > > > > + info = vp_dev->vqs[queue_index]; > > > > > + > > > > > + if (!info->vq->reset) > > > > > + return ERR_PTR(-EPERM); > > > > > + > > > > > + /* check queue reset status */ > > > > > + if (vp_modern_get_queue_reset(mdev, queue_index) != 1) > > > > > + return ERR_PTR(-EBUSY); > > > > > + > > > > > + vq = vp_setup_vq(param->vdev, queue_index, param->callback, param->name, > > > > > + param->ctx, info->msix_vector, param->ring_num); > > > > > + if (IS_ERR(vq)) > > > > > + return vq; > > > > > + > > > > > + vp_modern_set_queue_enable(&vp_dev->mdev, vq->index, true); > > > > > + > > > > > + msix_vec = vp_dev->vqs[queue_index]->msix_vector; > > > > > + if (vp_dev->per_vq_vectors && msix_vec != VIRTIO_MSI_NO_VECTOR) > > > > > + enable_irq(pci_irq_vector(vp_dev->pci_dev, msix_vec)); > > > > > > > > > > > > How about the INT-X case? > > > > > > Explained above. > > > > > > Thanks. > > > > > > > > > > > Thanks > > > > > > > > > > > > > + > > > > > + return vq; > > > > > +} > > > > > + > > > > > static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) > > > > > { > > > > > return vp_modern_config_vector(&vp_dev->mdev, vector); > > > > > @@ -284,6 +375,11 @@ static void del_vq(struct virtio_pci_vq_info *info) > > > > > struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); > > > > > struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > > > > > > > > > > + if (vq->reset) { > > > > > + vring_del_virtqueue(vq); > > > > > + return; > > > > > + } > > > > > + > > > > > if (vp_dev->msix_enabled) > > > > > vp_modern_queue_vector(mdev, vq->index, > > > > > VIRTIO_MSI_NO_VECTOR); > > > > > @@ -403,6 +499,8 @@ 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 = { > > > > > @@ -421,6 +519,8 @@ 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 */ > > > > > > > > > >
On Wed, 9 Feb 2022 13:44:06 +0800, Jason Wang <jasowang@redhat.com> wrote: > On Tue, Feb 8, 2022 at 3:44 PM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote: > > > > On Tue, 8 Feb 2022 10:55:37 +0800, Jason Wang <jasowang@redhat.com> wrote: > > > On Mon, Feb 7, 2022 at 4:19 PM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote: > > > > > > > > On Mon, 7 Feb 2022 14:57:13 +0800, Jason Wang <jasowang@redhat.com> wrote: > > > > > > > > > > 在 2022/1/26 下午3:35, Xuan Zhuo 写道: > > > > > > This patch implements virtio pci support for QUEUE RESET. > > > > > > > > > > > > Performing reset on a queue is divided into two steps: > > > > > > > > > > > > 1. reset_vq: reset one vq > > > > > > 2. enable_reset_vq: re-enable the reset queue > > > > > > > > > > > > In the first step, these tasks will be completed: > > > > > > 1. notify the hardware queue to reset > > > > > > 2. recycle the buffer from vq > > > > > > 3. release the ring of the vq > > > > > > > > > > > > The process of enable reset vq: > > > > > > vp_modern_enable_reset_vq() > > > > > > vp_enable_reset_vq() > > > > > > __vp_setup_vq() > > > > > > setup_vq() > > > > > > vring_setup_virtqueue() > > > > > > > > > > > > In this process, we added two parameters, vq and num, and finally passed > > > > > > them to vring_setup_virtqueue(). And reuse the original info and vq. > > > > > > > > > > > > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > > > > > > --- > > > > > > drivers/virtio/virtio_pci_common.c | 36 +++++++---- > > > > > > drivers/virtio/virtio_pci_common.h | 5 ++ > > > > > > drivers/virtio/virtio_pci_modern.c | 100 +++++++++++++++++++++++++++++ > > > > > > 3 files changed, 128 insertions(+), 13 deletions(-) > > > > > > > > > > > > diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c > > > > > > index c02936d29a31..ad21638fbf66 100644 > > > > > > --- a/drivers/virtio/virtio_pci_common.c > > > > > > +++ b/drivers/virtio/virtio_pci_common.c > > > > > > @@ -205,23 +205,28 @@ static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors, > > > > > > return err; > > > > > > } > > > > > > > > > > > > -static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, > > > > > > - void (*callback)(struct virtqueue *vq), > > > > > > - const char *name, > > > > > > - bool ctx, > > > > > > - u16 msix_vec, u16 num) > > > > > > +struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, > > > > > > + void (*callback)(struct virtqueue *vq), > > > > > > + const char *name, > > > > > > + bool ctx, > > > > > > + u16 msix_vec, u16 num) > > > > > > { > > > > > > struct virtio_pci_device *vp_dev = to_vp_device(vdev); > > > > > > - struct virtio_pci_vq_info *info = kmalloc(sizeof *info, GFP_KERNEL); > > > > > > + struct virtio_pci_vq_info *info; > > > > > > struct virtqueue *vq; > > > > > > unsigned long flags; > > > > > > > > > > > > - /* fill out our structure that represents an active queue */ > > > > > > - if (!info) > > > > > > - return ERR_PTR(-ENOMEM); > > > > > > + info = vp_dev->vqs[index]; > > > > > > + if (!info) { > > > > > > + info = kzalloc(sizeof *info, GFP_KERNEL); > > > > > > + > > > > > > + /* fill out our structure that represents an active queue */ > > > > > > + if (!info) > > > > > > + return ERR_PTR(-ENOMEM); > > > > > > + } > > > > > > > > > > > > vq = vp_dev->setup_vq(vp_dev, info, index, callback, name, ctx, > > > > > > - msix_vec, NULL, num); > > > > > > + msix_vec, info->vq, num); > > > > > > if (IS_ERR(vq)) > > > > > > goto out_info; > > > > > > > > > > > > @@ -238,6 +243,9 @@ static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, > > > > > > return vq; > > > > > > > > > > > > out_info: > > > > > > + if (info->vq && info->vq->reset) > > > > > > + return vq; > > > > > > + > > > > > > kfree(info); > > > > > > return vq; > > > > > > } > > > > > > @@ -248,9 +256,11 @@ 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_common.h b/drivers/virtio/virtio_pci_common.h > > > > > > index 65db92245e41..c1d15f7c0be4 100644 > > > > > > --- a/drivers/virtio/virtio_pci_common.h > > > > > > +++ b/drivers/virtio/virtio_pci_common.h > > > > > > @@ -119,6 +119,11 @@ int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs, > > > > > > struct virtqueue *vqs[], vq_callback_t *callbacks[], > > > > > > const char * const names[], const bool *ctx, > > > > > > struct irq_affinity *desc); > > > > > > +struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, > > > > > > + void (*callback)(struct virtqueue *vq), > > > > > > + const char *name, > > > > > > + bool ctx, > > > > > > + u16 msix_vec, u16 num); > > > > > > const char *vp_bus_name(struct virtio_device *vdev); > > > > > > > > > > > > /* Setup the affinity for a virtqueue: > > > > > > diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c > > > > > > index 2ce58de549de..6789411169e4 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 +179,94 @@ static void vp_reset(struct virtio_device *vdev) > > > > > > vp_disable_cbs(vdev); > > > > > > } > > > > > > > > > > > > +static int vp_modern_reset_vq(struct virtio_reset_vq *param) > > > > > > +{ > > > > > > + struct virtio_pci_device *vp_dev = to_vp_device(param->vdev); > > > > > > + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > > > > > > + struct virtio_pci_vq_info *info; > > > > > > + u16 msix_vec, queue_index; > > > > > > + unsigned long flags; > > > > > > + void *buf; > > > > > > + > > > > > > + if (!virtio_has_feature(param->vdev, VIRTIO_F_RING_RESET)) > > > > > > + return -ENOENT; > > > > > > + > > > > > > + queue_index = param->queue_index; > > > > > > + > > > > > > + vp_modern_set_queue_reset(mdev, queue_index); > > > > > > + > > > > > > + /* After write 1 to queue reset, the driver MUST wait for a read of > > > > > > + * queue reset to return 1. > > > > > > + */ > > > > > > + while (vp_modern_get_queue_reset(mdev, queue_index) != 1) > > > > > > + msleep(1); > > > > > > > > > > > > > > > Is this better to move this logic into vp_modern_set_queue_reset()? > > > > > > > > > > > > > OK. > > > > > > > > > > > > > > > + > > > > > > + info = vp_dev->vqs[queue_index]; > > > > > > + msix_vec = info->msix_vector; > > > > > > + > > > > > > + /* Disable VQ callback. */ > > > > > > + if (vp_dev->per_vq_vectors && msix_vec != VIRTIO_MSI_NO_VECTOR) > > > > > > + disable_irq(pci_irq_vector(vp_dev->pci_dev, msix_vec)); > > > > > > > > > > > > > > > How about the INTX case where irq is shared? I guess we need to disable > > > > > and enable the irq as well. > > > > > > > > For the INTX scenario, I don't think we need to disable/enable the irq. But I do > > > > have a mistake, I should put the following list_del(&info->node) here, so that > > > > when the irq comes, it will no longer operate this vq. > > > > > > > > In fact, for no INTX case, the disable_irq here is not necessary, according to > > > > the requirements of the spec, after reset, the device should not generate irq > > > > anymore. > > > > > > I may miss something but I don't think INTX differs from MSI from the > > > vq handler perspective. > > > > > > > Here just to prevent accidents. > > > > > > The problem is that if you don't disable/sync IRQ there could be a > > > race between the vq irq handler and the virtqueue_detach_unused_buf()? > > > > > > > > > > > > > > > > > > > > > > > + > > > > > > + while ((buf = virtqueue_detach_unused_buf(info->vq)) != NULL) > > > > > > + param->free_unused_cb(param, buf); > > > > > > > > > > > > > > > Any reason that we can't leave this logic to driver? (Or is there any > > > > > operations that must be done before the following operations?) > > > > > > > > As you commented before, we merged free unused buf and reset queue. > > > > > > > > I think it's a good note, otherwise, we're going to > > > > > > > > 1. reset vq > > > > 2. free unused(by driver) > > > > 3. free ring of vq > > > > > > Rethink about this, I'd prefer to leave it to the driver for consistency. > > > > > > E.g the virtqueue_detach_unused_buf() is called by each driver nowdays. > > > > In this case, go back to my previous design and add three helpers: > > > > int (*reset_vq)(); > > int (*free_reset_vq)(); > > So this is only needed if there are any transport specific operations. > But I don't see there's any. Yes, you are right. Performing reset on a queue is divided into four steps 1. virtio_config_ops->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() (new function) 4. virtio_config_ops->enable_reset_vq(): re-enable the reset queue Thanks. > > Thanks > > > int (*enable_reset_vq)(); > > > > Thanks. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > + > > > > > > + /* delete vq */ > > > > > > + spin_lock_irqsave(&vp_dev->lock, flags); > > > > > > + list_del(&info->node); > > > > > > + spin_unlock_irqrestore(&vp_dev->lock, flags); > > > > > > + > > > > > > + INIT_LIST_HEAD(&info->node); > > > > > > + > > > > > > + if (vp_dev->msix_enabled) > > > > > > + vp_modern_queue_vector(mdev, info->vq->index, > > > > > > + VIRTIO_MSI_NO_VECTOR); > > > > > > > > > > > > > > > I wonder if this is a must. > > > > > > > > > > > > > > > > + > > > > > > + if (!mdev->notify_base) > > > > > > + pci_iounmap(mdev->pci_dev, > > > > > > + (void __force __iomem *)info->vq->priv); > > > > > > > > > > > > > > > Is this a must? what happens if we simply don't do this? > > > > > > > > > > > > > The purpose of these two operations is mainly to be symmetrical with del_vq(). > > > > > > This is another question I want to ask. Any reason for calling > > > del_vq()? Is it because you need to exclude a vq from the vq handler? > > > > > > For any case, the MSI and notification stuff seems unnecessary. > > > > > > Thanks > > > > > > > > > > > > > > > > > > > > > > + > > > > > > + vring_reset_virtqueue(info->vq); > > > > > > + > > > > > > + return 0; > > > > > > +} > > > > > > + > > > > > > +static struct virtqueue *vp_modern_enable_reset_vq(struct virtio_reset_vq *param) > > > > > > +{ > > > > > > + struct virtio_pci_device *vp_dev = to_vp_device(param->vdev); > > > > > > + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > > > > > > + struct virtio_pci_vq_info *info; > > > > > > + u16 msix_vec, queue_index; > > > > > > + struct virtqueue *vq; > > > > > > + > > > > > > + if (!virtio_has_feature(param->vdev, VIRTIO_F_RING_RESET)) > > > > > > + return ERR_PTR(-ENOENT); > > > > > > + > > > > > > + queue_index = param->queue_index; > > > > > > + > > > > > > + info = vp_dev->vqs[queue_index]; > > > > > > + > > > > > > + if (!info->vq->reset) > > > > > > + return ERR_PTR(-EPERM); > > > > > > + > > > > > > + /* check queue reset status */ > > > > > > + if (vp_modern_get_queue_reset(mdev, queue_index) != 1) > > > > > > + return ERR_PTR(-EBUSY); > > > > > > + > > > > > > + vq = vp_setup_vq(param->vdev, queue_index, param->callback, param->name, > > > > > > + param->ctx, info->msix_vector, param->ring_num); > > > > > > + if (IS_ERR(vq)) > > > > > > + return vq; > > > > > > + > > > > > > + vp_modern_set_queue_enable(&vp_dev->mdev, vq->index, true); > > > > > > + > > > > > > + msix_vec = vp_dev->vqs[queue_index]->msix_vector; > > > > > > + if (vp_dev->per_vq_vectors && msix_vec != VIRTIO_MSI_NO_VECTOR) > > > > > > + enable_irq(pci_irq_vector(vp_dev->pci_dev, msix_vec)); > > > > > > > > > > > > > > > How about the INT-X case? > > > > > > > > Explained above. > > > > > > > > Thanks. > > > > > > > > > > > > > > Thanks > > > > > > > > > > > > > > > > + > > > > > > + return vq; > > > > > > +} > > > > > > + > > > > > > static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) > > > > > > { > > > > > > return vp_modern_config_vector(&vp_dev->mdev, vector); > > > > > > @@ -284,6 +375,11 @@ static void del_vq(struct virtio_pci_vq_info *info) > > > > > > struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); > > > > > > struct virtio_pci_modern_device *mdev = &vp_dev->mdev; > > > > > > > > > > > > + if (vq->reset) { > > > > > > + vring_del_virtqueue(vq); > > > > > > + return; > > > > > > + } > > > > > > + > > > > > > if (vp_dev->msix_enabled) > > > > > > vp_modern_queue_vector(mdev, vq->index, > > > > > > VIRTIO_MSI_NO_VECTOR); > > > > > > @@ -403,6 +499,8 @@ 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 = { > > > > > > @@ -421,6 +519,8 @@ 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_pci_common.c b/drivers/virtio/virtio_pci_common.c index c02936d29a31..ad21638fbf66 100644 --- a/drivers/virtio/virtio_pci_common.c +++ b/drivers/virtio/virtio_pci_common.c @@ -205,23 +205,28 @@ static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors, return err; } -static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, - void (*callback)(struct virtqueue *vq), - const char *name, - bool ctx, - u16 msix_vec, u16 num) +struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, + void (*callback)(struct virtqueue *vq), + const char *name, + bool ctx, + u16 msix_vec, u16 num) { struct virtio_pci_device *vp_dev = to_vp_device(vdev); - struct virtio_pci_vq_info *info = kmalloc(sizeof *info, GFP_KERNEL); + struct virtio_pci_vq_info *info; struct virtqueue *vq; unsigned long flags; - /* fill out our structure that represents an active queue */ - if (!info) - return ERR_PTR(-ENOMEM); + info = vp_dev->vqs[index]; + if (!info) { + info = kzalloc(sizeof *info, GFP_KERNEL); + + /* fill out our structure that represents an active queue */ + if (!info) + return ERR_PTR(-ENOMEM); + } vq = vp_dev->setup_vq(vp_dev, info, index, callback, name, ctx, - msix_vec, NULL, num); + msix_vec, info->vq, num); if (IS_ERR(vq)) goto out_info; @@ -238,6 +243,9 @@ static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, return vq; out_info: + if (info->vq && info->vq->reset) + return vq; + kfree(info); return vq; } @@ -248,9 +256,11 @@ 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_common.h b/drivers/virtio/virtio_pci_common.h index 65db92245e41..c1d15f7c0be4 100644 --- a/drivers/virtio/virtio_pci_common.h +++ b/drivers/virtio/virtio_pci_common.h @@ -119,6 +119,11 @@ int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs, struct virtqueue *vqs[], vq_callback_t *callbacks[], const char * const names[], const bool *ctx, struct irq_affinity *desc); +struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned index, + void (*callback)(struct virtqueue *vq), + const char *name, + bool ctx, + u16 msix_vec, u16 num); const char *vp_bus_name(struct virtio_device *vdev); /* Setup the affinity for a virtqueue: diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c index 2ce58de549de..6789411169e4 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 +179,94 @@ static void vp_reset(struct virtio_device *vdev) vp_disable_cbs(vdev); } +static int vp_modern_reset_vq(struct virtio_reset_vq *param) +{ + struct virtio_pci_device *vp_dev = to_vp_device(param->vdev); + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + struct virtio_pci_vq_info *info; + u16 msix_vec, queue_index; + unsigned long flags; + void *buf; + + if (!virtio_has_feature(param->vdev, VIRTIO_F_RING_RESET)) + return -ENOENT; + + queue_index = param->queue_index; + + vp_modern_set_queue_reset(mdev, queue_index); + + /* After write 1 to queue reset, the driver MUST wait for a read of + * queue reset to return 1. + */ + while (vp_modern_get_queue_reset(mdev, queue_index) != 1) + msleep(1); + + info = vp_dev->vqs[queue_index]; + msix_vec = info->msix_vector; + + /* Disable VQ callback. */ + if (vp_dev->per_vq_vectors && msix_vec != VIRTIO_MSI_NO_VECTOR) + disable_irq(pci_irq_vector(vp_dev->pci_dev, msix_vec)); + + while ((buf = virtqueue_detach_unused_buf(info->vq)) != NULL) + param->free_unused_cb(param, buf); + + /* delete vq */ + spin_lock_irqsave(&vp_dev->lock, flags); + list_del(&info->node); + spin_unlock_irqrestore(&vp_dev->lock, flags); + + INIT_LIST_HEAD(&info->node); + + if (vp_dev->msix_enabled) + vp_modern_queue_vector(mdev, info->vq->index, + VIRTIO_MSI_NO_VECTOR); + + if (!mdev->notify_base) + pci_iounmap(mdev->pci_dev, + (void __force __iomem *)info->vq->priv); + + vring_reset_virtqueue(info->vq); + + return 0; +} + +static struct virtqueue *vp_modern_enable_reset_vq(struct virtio_reset_vq *param) +{ + struct virtio_pci_device *vp_dev = to_vp_device(param->vdev); + struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + struct virtio_pci_vq_info *info; + u16 msix_vec, queue_index; + struct virtqueue *vq; + + if (!virtio_has_feature(param->vdev, VIRTIO_F_RING_RESET)) + return ERR_PTR(-ENOENT); + + queue_index = param->queue_index; + + info = vp_dev->vqs[queue_index]; + + if (!info->vq->reset) + return ERR_PTR(-EPERM); + + /* check queue reset status */ + if (vp_modern_get_queue_reset(mdev, queue_index) != 1) + return ERR_PTR(-EBUSY); + + vq = vp_setup_vq(param->vdev, queue_index, param->callback, param->name, + param->ctx, info->msix_vector, param->ring_num); + if (IS_ERR(vq)) + return vq; + + vp_modern_set_queue_enable(&vp_dev->mdev, vq->index, true); + + msix_vec = vp_dev->vqs[queue_index]->msix_vector; + if (vp_dev->per_vq_vectors && msix_vec != VIRTIO_MSI_NO_VECTOR) + enable_irq(pci_irq_vector(vp_dev->pci_dev, msix_vec)); + + return vq; +} + static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) { return vp_modern_config_vector(&vp_dev->mdev, vector); @@ -284,6 +375,11 @@ static void del_vq(struct virtio_pci_vq_info *info) struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); struct virtio_pci_modern_device *mdev = &vp_dev->mdev; + if (vq->reset) { + vring_del_virtqueue(vq); + return; + } + if (vp_dev->msix_enabled) vp_modern_queue_vector(mdev, vq->index, VIRTIO_MSI_NO_VECTOR); @@ -403,6 +499,8 @@ 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 = { @@ -421,6 +519,8 @@ 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 */
This patch implements virtio pci support for QUEUE RESET. Performing reset on a queue is divided into two steps: 1. reset_vq: reset one vq 2. enable_reset_vq: re-enable the reset queue In the first step, these tasks will be completed: 1. notify the hardware queue to reset 2. recycle the buffer from vq 3. release the ring of the vq The process of enable reset vq: vp_modern_enable_reset_vq() vp_enable_reset_vq() __vp_setup_vq() setup_vq() vring_setup_virtqueue() In this process, we added two parameters, vq and num, and finally passed them to vring_setup_virtqueue(). And reuse the original info and vq. Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> --- drivers/virtio/virtio_pci_common.c | 36 +++++++---- drivers/virtio/virtio_pci_common.h | 5 ++ drivers/virtio/virtio_pci_modern.c | 100 +++++++++++++++++++++++++++++ 3 files changed, 128 insertions(+), 13 deletions(-)