[PATCH 0/7] Doorbell mapping support for virito-pci vDPA

[PATCH 0/7] Doorbell mapping support for virito-pci vDPA

[Jason Wang]

Hi All:

This series implements the doorbell mapping support for virtio-pci
vDPA driver. Tested with page-per-vq=on in a nested guest.

Please review

Thanks

Jason Wang (7):
  virtio_pci_modern: introduce helper to map vq notify area
  virtio-pci library: switch to use vp_modern_map_vq_notify()
  vp_vdpa: switch to use vp_modern_map_vq_notify()
  virtio_pci_modern: hide vp_modern_get_queue_notify_off()
  virito_pci libray: hide vp_modern_map_capability()
  virtio-pci library: report resource address
  vp_vdpa: report doorbell address

 drivers/vdpa/virtio_pci/vp_vdpa.c      | 26 ++++++++--
 drivers/virtio/virtio_pci_modern.c     | 27 +---------
 drivers/virtio/virtio_pci_modern_dev.c | 68 +++++++++++++++++++++-----
 include/linux/virtio_pci_modern.h      | 11 ++---
 4 files changed, 83 insertions(+), 49 deletions(-)

-- 
2.18.1

[PATCH 1/7] virtio_pci_modern: introduce helper to map vq notify area

[Jason Wang]

This patch factors out the logic of vq notify area mapping. Following
patches will switch to use this common helpers for both virtio_pci
library and virtio-pci vDPA driver.

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 drivers/virtio/virtio_pci_modern_dev.c | 35 ++++++++++++++++++++++++++
 include/linux/virtio_pci_modern.h      |  2 ++
 2 files changed, 37 insertions(+)

diff --git a/drivers/virtio/virtio_pci_modern_dev.c b/drivers/virtio/virtio_pci_modern_dev.c
index cbd667496bb1..28cb5847fafa 100644
--- a/drivers/virtio/virtio_pci_modern_dev.c
+++ b/drivers/virtio/virtio_pci_modern_dev.c
@@ -593,6 +593,41 @@ u16 vp_modern_get_queue_notify_off(struct virtio_pci_modern_device *mdev,
 }
 EXPORT_SYMBOL_GPL(vp_modern_get_queue_notify_off);
 
+/*
+ * vp_modern_map_vq_notify - map notification area for a
+ * specific virtqueue
+ * @mdev: the modern virtio-pci device
+ * @index: the queue index
+ *
+ * Returns the address of the notification area
+ */
+void *vp_modern_map_vq_notify(struct virtio_pci_modern_device *mdev,
+			      u16 index)
+{
+	u16 off = vp_modern_get_queue_notify_off(mdev, index);
+
+	if (mdev->notify_base) {
+		/* offset should not wrap */
+		if ((u64)off * mdev->notify_offset_multiplier + 2
+			> mdev->notify_len) {
+			dev_warn(&mdev->pci_dev->dev,
+				 "bad notification offset %u (x %u) "
+				 "for queue %u > %zd",
+				 off, mdev->notify_offset_multiplier,
+				 index, mdev->notify_len);
+			return NULL;
+		}
+		return (void __force *)mdev->notify_base +
+			off * mdev->notify_offset_multiplier;
+	} else {
+		return (void __force *)vp_modern_map_capability(mdev,
+				       mdev->notify_map_cap, 2, 2,
+				       off * mdev->notify_offset_multiplier, 2,
+				       NULL);
+	}
+}
+EXPORT_SYMBOL_GPL(vp_modern_map_vq_notify);
+
 MODULE_VERSION("0.1");
 MODULE_DESCRIPTION("Modern Virtio PCI Device");
 MODULE_AUTHOR("Jason Wang <jasowang@redhat.com>");
diff --git a/include/linux/virtio_pci_modern.h b/include/linux/virtio_pci_modern.h
index f26acbeec965..1b95d39b00fc 100644
--- a/include/linux/virtio_pci_modern.h
+++ b/include/linux/virtio_pci_modern.h
@@ -106,6 +106,8 @@ void __iomem *vp_modern_map_capability(struct virtio_pci_modern_device *mdev, in
 				       u32 align,
 				       u32 start, u32 size,
 				       size_t *len);
+void *vp_modern_map_vq_notify(struct virtio_pci_modern_device *mdev,
+                              u16 index);
 int vp_modern_probe(struct virtio_pci_modern_device *mdev);
 void vp_modern_remove(struct virtio_pci_modern_device *mdev);
 #endif
-- 
2.18.1

Re: [PATCH 1/7] virtio_pci_modern: introduce helper to map vq notify area

[Eli Cohen]

On Thu, Apr 15, 2021 at 03:31:41AM -0400, Jason Wang wrote:
> This patch factors out the logic of vq notify area mapping. Following
> patches will switch to use this common helpers for both virtio_pci
> library and virtio-pci vDPA driver.
> 
> Signed-off-by: Jason Wang <jasowang@redhat.com>

Reviewed-by: Eli Cohen <elic@nvidia.com>

> ---
>  drivers/virtio/virtio_pci_modern_dev.c | 35 ++++++++++++++++++++++++++
>  include/linux/virtio_pci_modern.h      |  2 ++
>  2 files changed, 37 insertions(+)
> 
> diff --git a/drivers/virtio/virtio_pci_modern_dev.c b/drivers/virtio/virtio_pci_modern_dev.c
> index cbd667496bb1..28cb5847fafa 100644
> --- a/drivers/virtio/virtio_pci_modern_dev.c
> +++ b/drivers/virtio/virtio_pci_modern_dev.c
> @@ -593,6 +593,41 @@ u16 vp_modern_get_queue_notify_off(struct virtio_pci_modern_device *mdev,
>  }
>  EXPORT_SYMBOL_GPL(vp_modern_get_queue_notify_off);
>  
> +/*
> + * vp_modern_map_vq_notify - map notification area for a
> + * specific virtqueue
> + * @mdev: the modern virtio-pci device
> + * @index: the queue index
> + *
> + * Returns the address of the notification area
> + */
> +void *vp_modern_map_vq_notify(struct virtio_pci_modern_device *mdev,
> +			      u16 index)
> +{
> +	u16 off = vp_modern_get_queue_notify_off(mdev, index);
> +
> +	if (mdev->notify_base) {
> +		/* offset should not wrap */
> +		if ((u64)off * mdev->notify_offset_multiplier + 2
> +			> mdev->notify_len) {
> +			dev_warn(&mdev->pci_dev->dev,
> +				 "bad notification offset %u (x %u) "
> +				 "for queue %u > %zd",
> +				 off, mdev->notify_offset_multiplier,
> +				 index, mdev->notify_len);
> +			return NULL;
> +		}
> +		return (void __force *)mdev->notify_base +
> +			off * mdev->notify_offset_multiplier;
> +	} else {
> +		return (void __force *)vp_modern_map_capability(mdev,
> +				       mdev->notify_map_cap, 2, 2,
> +				       off * mdev->notify_offset_multiplier, 2,
> +				       NULL);
> +	}
> +}
> +EXPORT_SYMBOL_GPL(vp_modern_map_vq_notify);
> +
>  MODULE_VERSION("0.1");
>  MODULE_DESCRIPTION("Modern Virtio PCI Device");
>  MODULE_AUTHOR("Jason Wang <jasowang@redhat.com>");
> diff --git a/include/linux/virtio_pci_modern.h b/include/linux/virtio_pci_modern.h
> index f26acbeec965..1b95d39b00fc 100644
> --- a/include/linux/virtio_pci_modern.h
> +++ b/include/linux/virtio_pci_modern.h
> @@ -106,6 +106,8 @@ void __iomem *vp_modern_map_capability(struct virtio_pci_modern_device *mdev, in
>  				       u32 align,
>  				       u32 start, u32 size,
>  				       size_t *len);
> +void *vp_modern_map_vq_notify(struct virtio_pci_modern_device *mdev,
> +                              u16 index);
>  int vp_modern_probe(struct virtio_pci_modern_device *mdev);
>  void vp_modern_remove(struct virtio_pci_modern_device *mdev);
>  #endif
> -- 
> 2.18.1
> 

[PATCH 2/7] virtio-pci library: switch to use vp_modern_map_vq_notify()

[Jason Wang]

This patch switch to use vp_modern_map_notify() for virtio-pci
library.

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 drivers/virtio/virtio_pci_modern.c | 27 ++-------------------------
 1 file changed, 2 insertions(+), 25 deletions(-)

diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c
index fbd4ebc00eb6..29607d9bd95c 100644
--- a/drivers/virtio/virtio_pci_modern.c
+++ b/drivers/virtio/virtio_pci_modern.c
@@ -192,7 +192,7 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
 
 	struct virtio_pci_modern_device *mdev = &vp_dev->mdev;
 	struct virtqueue *vq;
-	u16 num, off;
+	u16 num;
 	int err;
 
 	if (index >= vp_modern_get_num_queues(mdev))
@@ -208,9 +208,6 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
 		return ERR_PTR(-EINVAL);
 	}
 
-	/* get offset of notification word for this vq */
-	off = vp_modern_get_queue_notify_off(mdev, index);
-
 	info->msix_vector = msix_vec;
 
 	/* create the vring */
@@ -227,27 +224,7 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
 				virtqueue_get_avail_addr(vq),
 				virtqueue_get_used_addr(vq));
 
-	if (mdev->notify_base) {
-		/* offset should not wrap */
-		if ((u64)off * mdev->notify_offset_multiplier + 2
-		    > mdev->notify_len) {
-			dev_warn(&mdev->pci_dev->dev,
-				 "bad notification offset %u (x %u) "
-				 "for queue %u > %zd",
-				 off, mdev->notify_offset_multiplier,
-				 index, mdev->notify_len);
-			err = -EINVAL;
-			goto err_map_notify;
-		}
-		vq->priv = (void __force *)mdev->notify_base +
-			off * mdev->notify_offset_multiplier;
-	} else {
-		vq->priv = (void __force *)vp_modern_map_capability(mdev,
-							  mdev->notify_map_cap, 2, 2,
-							  off * mdev->notify_offset_multiplier, 2,
-							  NULL);
-	}
-
+	vq->priv = vp_modern_map_vq_notify(mdev, index);
 	if (!vq->priv) {
 		err = -ENOMEM;
 		goto err_map_notify;
-- 
2.18.1

Re: [PATCH 2/7] virtio-pci library: switch to use vp_modern_map_vq_notify()

[Eli Cohen]

On Thu, Apr 15, 2021 at 03:31:42AM -0400, Jason Wang wrote:
> This patch switch to use vp_modern_map_notify() for virtio-pci
> library.
> 
> Signed-off-by: Jason Wang <jasowang@redhat.com>

Reviewed-by: Eli Cohen <elic@nvidia.com>

> ---
>  drivers/virtio/virtio_pci_modern.c | 27 ++-------------------------
>  1 file changed, 2 insertions(+), 25 deletions(-)
> 
> diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c
> index fbd4ebc00eb6..29607d9bd95c 100644
> --- a/drivers/virtio/virtio_pci_modern.c
> +++ b/drivers/virtio/virtio_pci_modern.c
> @@ -192,7 +192,7 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
>  
>  	struct virtio_pci_modern_device *mdev = &vp_dev->mdev;
>  	struct virtqueue *vq;
> -	u16 num, off;
> +	u16 num;
>  	int err;
>  
>  	if (index >= vp_modern_get_num_queues(mdev))
> @@ -208,9 +208,6 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
>  		return ERR_PTR(-EINVAL);
>  	}
>  
> -	/* get offset of notification word for this vq */
> -	off = vp_modern_get_queue_notify_off(mdev, index);
> -
>  	info->msix_vector = msix_vec;
>  
>  	/* create the vring */
> @@ -227,27 +224,7 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
>  				virtqueue_get_avail_addr(vq),
>  				virtqueue_get_used_addr(vq));
>  
> -	if (mdev->notify_base) {
> -		/* offset should not wrap */
> -		if ((u64)off * mdev->notify_offset_multiplier + 2
> -		    > mdev->notify_len) {
> -			dev_warn(&mdev->pci_dev->dev,
> -				 "bad notification offset %u (x %u) "
> -				 "for queue %u > %zd",
> -				 off, mdev->notify_offset_multiplier,
> -				 index, mdev->notify_len);
> -			err = -EINVAL;
> -			goto err_map_notify;
> -		}
> -		vq->priv = (void __force *)mdev->notify_base +
> -			off * mdev->notify_offset_multiplier;
> -	} else {
> -		vq->priv = (void __force *)vp_modern_map_capability(mdev,
> -							  mdev->notify_map_cap, 2, 2,
> -							  off * mdev->notify_offset_multiplier, 2,
> -							  NULL);
> -	}
> -
> +	vq->priv = vp_modern_map_vq_notify(mdev, index);
>  	if (!vq->priv) {
>  		err = -ENOMEM;
>  		goto err_map_notify;
> -- 
> 2.18.1
> 

[PATCH 3/7] vp_vdpa: switch to use vp_modern_map_vq_notify()

[Jason Wang]

This patch switches to use vp_vdpa to use vp_modern_map_notify().

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 drivers/vdpa/virtio_pci/vp_vdpa.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c b/drivers/vdpa/virtio_pci/vp_vdpa.c
index 1321a2fcd088..2afc90645660 100644
--- a/drivers/vdpa/virtio_pci/vp_vdpa.c
+++ b/drivers/vdpa/virtio_pci/vp_vdpa.c
@@ -369,7 +369,6 @@ static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	struct virtio_pci_modern_device *mdev;
 	struct device *dev = &pdev->dev;
 	struct vp_vdpa *vp_vdpa;
-	u16 notify_off;
 	int ret, i;
 
 	ret = pcim_enable_device(pdev);
@@ -415,10 +414,12 @@ static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	}
 
 	for (i = 0; i < vp_vdpa->queues; i++) {
-		notify_off = vp_modern_get_queue_notify_off(mdev, i);
 		vp_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
-		vp_vdpa->vring[i].notify = mdev->notify_base +
-			notify_off * mdev->notify_offset_multiplier;
+		vp_vdpa->vring[i].notify = vp_modern_map_vq_notify(mdev, i);
+		if (!vp_vdpa->vring[i].notify) {
+			dev_warn(&pdev->dev, "Fail to map vq notify %d\n", i);
+			goto err;
+		}
 	}
 	vp_vdpa->config_irq = VIRTIO_MSI_NO_VECTOR;
 
-- 
2.18.1

Re: [PATCH 3/7] vp_vdpa: switch to use vp_modern_map_vq_notify()

[Eli Cohen]

On Thu, Apr 15, 2021 at 03:31:43AM -0400, Jason Wang wrote:
> This patch switches to use vp_vdpa to use vp_modern_map_notify().
> 
> Signed-off-by: Jason Wang <jasowang@redhat.com>

Reviewed-by: Eli Cohen <elic@nvidia.com>

> ---
>  drivers/vdpa/virtio_pci/vp_vdpa.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c b/drivers/vdpa/virtio_pci/vp_vdpa.c
> index 1321a2fcd088..2afc90645660 100644
> --- a/drivers/vdpa/virtio_pci/vp_vdpa.c
> +++ b/drivers/vdpa/virtio_pci/vp_vdpa.c
> @@ -369,7 +369,6 @@ static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
>  	struct virtio_pci_modern_device *mdev;
>  	struct device *dev = &pdev->dev;
>  	struct vp_vdpa *vp_vdpa;
> -	u16 notify_off;
>  	int ret, i;
>  
>  	ret = pcim_enable_device(pdev);
> @@ -415,10 +414,12 @@ static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
>  	}
>  
>  	for (i = 0; i < vp_vdpa->queues; i++) {
> -		notify_off = vp_modern_get_queue_notify_off(mdev, i);
>  		vp_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
> -		vp_vdpa->vring[i].notify = mdev->notify_base +
> -			notify_off * mdev->notify_offset_multiplier;
> +		vp_vdpa->vring[i].notify = vp_modern_map_vq_notify(mdev, i);
> +		if (!vp_vdpa->vring[i].notify) {
> +			dev_warn(&pdev->dev, "Fail to map vq notify %d\n", i);
> +			goto err;
> +		}
>  	}
>  	vp_vdpa->config_irq = VIRTIO_MSI_NO_VECTOR;
>  
> -- 
> 2.18.1
> 

[PATCH 4/7] virtio_pci_modern: hide vp_modern_get_queue_notify_off()

[Jason Wang]

All users (both virtio-pci library and vp_vdpa driver) has been
switched to use vp_modern_map_vq_notify(). So there's no need to
export the low level helper of vp_modern_get_queue_notify_off().

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 drivers/virtio/virtio_pci_modern_dev.c | 5 ++---
 include/linux/virtio_pci_modern.h      | 2 --
 2 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/virtio/virtio_pci_modern_dev.c b/drivers/virtio/virtio_pci_modern_dev.c
index 28cb5847fafa..5a657e56b46d 100644
--- a/drivers/virtio/virtio_pci_modern_dev.c
+++ b/drivers/virtio/virtio_pci_modern_dev.c
@@ -584,14 +584,13 @@ EXPORT_SYMBOL_GPL(vp_modern_get_num_queues);
  *
  * Returns the notification offset for a virtqueue
  */
-u16 vp_modern_get_queue_notify_off(struct virtio_pci_modern_device *mdev,
-				   u16 index)
+static u16 vp_modern_get_queue_notify_off(struct virtio_pci_modern_device *mdev,
+					  u16 index)
 {
 	vp_iowrite16(index, &mdev->common->queue_select);
 
 	return vp_ioread16(&mdev->common->queue_notify_off);
 }
-EXPORT_SYMBOL_GPL(vp_modern_get_queue_notify_off);
 
 /*
  * vp_modern_map_vq_notify - map notification area for a
diff --git a/include/linux/virtio_pci_modern.h b/include/linux/virtio_pci_modern.h
index 1b95d39b00fc..179a2fb4bf37 100644
--- a/include/linux/virtio_pci_modern.h
+++ b/include/linux/virtio_pci_modern.h
@@ -99,8 +99,6 @@ void vp_modern_set_queue_size(struct virtio_pci_modern_device *mdev,
 u16 vp_modern_get_queue_size(struct virtio_pci_modern_device *mdev,
 			     u16 idx);
 u16 vp_modern_get_num_queues(struct virtio_pci_modern_device *mdev);
-u16 vp_modern_get_queue_notify_off(struct virtio_pci_modern_device *mdev,
-				   u16 idx);
 void __iomem *vp_modern_map_capability(struct virtio_pci_modern_device *mdev, int off,
 				       size_t minlen,
 				       u32 align,
-- 
2.18.1

Re: [PATCH 4/7] virtio_pci_modern: hide vp_modern_get_queue_notify_off()

[Eli Cohen]

On Thu, Apr 15, 2021 at 03:31:44AM -0400, Jason Wang wrote:
> All users (both virtio-pci library and vp_vdpa driver) has been
> switched to use vp_modern_map_vq_notify(). So there's no need to
> export the low level helper of vp_modern_get_queue_notify_off().
> 
> Signed-off-by: Jason Wang <jasowang@redhat.com>

Reviewed-by: Eli Cohen <elic@nvidia.com>

> ---
>  drivers/virtio/virtio_pci_modern_dev.c | 5 ++---
>  include/linux/virtio_pci_modern.h      | 2 --
>  2 files changed, 2 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/virtio/virtio_pci_modern_dev.c b/drivers/virtio/virtio_pci_modern_dev.c
> index 28cb5847fafa..5a657e56b46d 100644
> --- a/drivers/virtio/virtio_pci_modern_dev.c
> +++ b/drivers/virtio/virtio_pci_modern_dev.c
> @@ -584,14 +584,13 @@ EXPORT_SYMBOL_GPL(vp_modern_get_num_queues);
>   *
>   * Returns the notification offset for a virtqueue
>   */
> -u16 vp_modern_get_queue_notify_off(struct virtio_pci_modern_device *mdev,
> -				   u16 index)
> +static u16 vp_modern_get_queue_notify_off(struct virtio_pci_modern_device *mdev,
> +					  u16 index)
>  {
>  	vp_iowrite16(index, &mdev->common->queue_select);
>  
>  	return vp_ioread16(&mdev->common->queue_notify_off);
>  }
> -EXPORT_SYMBOL_GPL(vp_modern_get_queue_notify_off);
>  
>  /*
>   * vp_modern_map_vq_notify - map notification area for a
> diff --git a/include/linux/virtio_pci_modern.h b/include/linux/virtio_pci_modern.h
> index 1b95d39b00fc..179a2fb4bf37 100644
> --- a/include/linux/virtio_pci_modern.h
> +++ b/include/linux/virtio_pci_modern.h
> @@ -99,8 +99,6 @@ void vp_modern_set_queue_size(struct virtio_pci_modern_device *mdev,
>  u16 vp_modern_get_queue_size(struct virtio_pci_modern_device *mdev,
>  			     u16 idx);
>  u16 vp_modern_get_num_queues(struct virtio_pci_modern_device *mdev);
> -u16 vp_modern_get_queue_notify_off(struct virtio_pci_modern_device *mdev,
> -				   u16 idx);
>  void __iomem *vp_modern_map_capability(struct virtio_pci_modern_device *mdev, int off,
>  				       size_t minlen,
>  				       u32 align,
> -- 
> 2.18.1
> 

[PATCH 5/7] virito_pci libray: hide vp_modern_map_capability()

[Jason Wang]

No user now and the capability should not be setup
externally. Instead, every access to the capability should be done via
virtio_pci_modern_device.

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 drivers/virtio/virtio_pci_modern_dev.c | 10 ++++------
 include/linux/virtio_pci_modern.h      |  5 -----
 2 files changed, 4 insertions(+), 11 deletions(-)

diff --git a/drivers/virtio/virtio_pci_modern_dev.c b/drivers/virtio/virtio_pci_modern_dev.c
index 5a657e56b46d..9c241c9bd920 100644
--- a/drivers/virtio/virtio_pci_modern_dev.c
+++ b/drivers/virtio/virtio_pci_modern_dev.c
@@ -16,11 +16,10 @@
  *
  * Returns the io address of for the part of the capability
  */
-void __iomem *vp_modern_map_capability(struct virtio_pci_modern_device *mdev, int off,
-				       size_t minlen,
-				       u32 align,
-				       u32 start, u32 size,
-				       size_t *len)
+static void __iomem *
+vp_modern_map_capability(struct virtio_pci_modern_device *mdev, int off,
+			 size_t minlen, u32 align, u32 start, u32 size,
+			 size_t *len)
 {
 	struct pci_dev *dev = mdev->pci_dev;
 	u8 bar;
@@ -90,7 +89,6 @@ void __iomem *vp_modern_map_capability(struct virtio_pci_modern_device *mdev, in
 			length, offset, bar);
 	return p;
 }
-EXPORT_SYMBOL_GPL(vp_modern_map_capability);
 
 /**
  * virtio_pci_find_capability - walk capabilities to find device info.
diff --git a/include/linux/virtio_pci_modern.h b/include/linux/virtio_pci_modern.h
index 179a2fb4bf37..e6e7072413c1 100644
--- a/include/linux/virtio_pci_modern.h
+++ b/include/linux/virtio_pci_modern.h
@@ -99,11 +99,6 @@ void vp_modern_set_queue_size(struct virtio_pci_modern_device *mdev,
 u16 vp_modern_get_queue_size(struct virtio_pci_modern_device *mdev,
 			     u16 idx);
 u16 vp_modern_get_num_queues(struct virtio_pci_modern_device *mdev);
-void __iomem *vp_modern_map_capability(struct virtio_pci_modern_device *mdev, int off,
-				       size_t minlen,
-				       u32 align,
-				       u32 start, u32 size,
-				       size_t *len);
 void *vp_modern_map_vq_notify(struct virtio_pci_modern_device *mdev,
                               u16 index);
 int vp_modern_probe(struct virtio_pci_modern_device *mdev);
-- 
2.18.1

Re: [PATCH 5/7] virito_pci libray: hide vp_modern_map_capability()

[Eli Cohen]

On Thu, Apr 15, 2021 at 03:31:45AM -0400, Jason Wang wrote:
> No user now and the capability should not be setup
> externally. Instead, every access to the capability should be done via
> virtio_pci_modern_device.
> 
> Signed-off-by: Jason Wang <jasowang@redhat.com>

Reviewed-by: Eli Cohen <elic@nvidia.com>

> ---
>  drivers/virtio/virtio_pci_modern_dev.c | 10 ++++------
>  include/linux/virtio_pci_modern.h      |  5 -----
>  2 files changed, 4 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/virtio/virtio_pci_modern_dev.c b/drivers/virtio/virtio_pci_modern_dev.c
> index 5a657e56b46d..9c241c9bd920 100644
> --- a/drivers/virtio/virtio_pci_modern_dev.c
> +++ b/drivers/virtio/virtio_pci_modern_dev.c
> @@ -16,11 +16,10 @@
>   *
>   * Returns the io address of for the part of the capability
>   */
> -void __iomem *vp_modern_map_capability(struct virtio_pci_modern_device *mdev, int off,
> -				       size_t minlen,
> -				       u32 align,
> -				       u32 start, u32 size,
> -				       size_t *len)
> +static void __iomem *
> +vp_modern_map_capability(struct virtio_pci_modern_device *mdev, int off,
> +			 size_t minlen, u32 align, u32 start, u32 size,
> +			 size_t *len)
>  {
>  	struct pci_dev *dev = mdev->pci_dev;
>  	u8 bar;
> @@ -90,7 +89,6 @@ void __iomem *vp_modern_map_capability(struct virtio_pci_modern_device *mdev, in
>  			length, offset, bar);
>  	return p;
>  }
> -EXPORT_SYMBOL_GPL(vp_modern_map_capability);
>  
>  /**
>   * virtio_pci_find_capability - walk capabilities to find device info.
> diff --git a/include/linux/virtio_pci_modern.h b/include/linux/virtio_pci_modern.h
> index 179a2fb4bf37..e6e7072413c1 100644
> --- a/include/linux/virtio_pci_modern.h
> +++ b/include/linux/virtio_pci_modern.h
> @@ -99,11 +99,6 @@ void vp_modern_set_queue_size(struct virtio_pci_modern_device *mdev,
>  u16 vp_modern_get_queue_size(struct virtio_pci_modern_device *mdev,
>  			     u16 idx);
>  u16 vp_modern_get_num_queues(struct virtio_pci_modern_device *mdev);
> -void __iomem *vp_modern_map_capability(struct virtio_pci_modern_device *mdev, int off,
> -				       size_t minlen,
> -				       u32 align,
> -				       u32 start, u32 size,
> -				       size_t *len);
>  void *vp_modern_map_vq_notify(struct virtio_pci_modern_device *mdev,
>                                u16 index);
>  int vp_modern_probe(struct virtio_pci_modern_device *mdev);
> -- 
> 2.18.1
> 

[PATCH 6/7] virtio-pci library: report resource address

[Jason Wang]

Sometimes it might be useful to report the capability physical
address. One example is to report the physical address of the doorbell
in order to be mapped by userspace.

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 drivers/vdpa/virtio_pci/vp_vdpa.c      |  3 ++-
 drivers/virtio/virtio_pci_modern.c     |  2 +-
 drivers/virtio/virtio_pci_modern_dev.c | 24 +++++++++++++++++-------
 include/linux/virtio_pci_modern.h      |  4 +++-
 4 files changed, 23 insertions(+), 10 deletions(-)

diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c b/drivers/vdpa/virtio_pci/vp_vdpa.c
index 2afc90645660..98205e54d089 100644
--- a/drivers/vdpa/virtio_pci/vp_vdpa.c
+++ b/drivers/vdpa/virtio_pci/vp_vdpa.c
@@ -415,7 +415,8 @@ static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 
 	for (i = 0; i < vp_vdpa->queues; i++) {
 		vp_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
-		vp_vdpa->vring[i].notify = vp_modern_map_vq_notify(mdev, i);
+		vp_vdpa->vring[i].notify =
+			vp_modern_map_vq_notify(mdev, i, NULL);
 		if (!vp_vdpa->vring[i].notify) {
 			dev_warn(&pdev->dev, "Fail to map vq notify %d\n", i);
 			goto err;
diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c
index 29607d9bd95c..722ea44e7579 100644
--- a/drivers/virtio/virtio_pci_modern.c
+++ b/drivers/virtio/virtio_pci_modern.c
@@ -224,7 +224,7 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
 				virtqueue_get_avail_addr(vq),
 				virtqueue_get_used_addr(vq));
 
-	vq->priv = vp_modern_map_vq_notify(mdev, index);
+	vq->priv = vp_modern_map_vq_notify(mdev, index, NULL);
 	if (!vq->priv) {
 		err = -ENOMEM;
 		goto err_map_notify;
diff --git a/drivers/virtio/virtio_pci_modern_dev.c b/drivers/virtio/virtio_pci_modern_dev.c
index 9c241c9bd920..ae87b3fa8858 100644
--- a/drivers/virtio/virtio_pci_modern_dev.c
+++ b/drivers/virtio/virtio_pci_modern_dev.c
@@ -13,13 +13,14 @@
  * @start: start from the capability
  * @size: map size
  * @len: the length that is actually mapped
+ * @pa: physical address of the capability
  *
  * Returns the io address of for the part of the capability
  */
 static void __iomem *
 vp_modern_map_capability(struct virtio_pci_modern_device *mdev, int off,
 			 size_t minlen, u32 align, u32 start, u32 size,
-			 size_t *len)
+			 size_t *len, resource_size_t *pa)
 {
 	struct pci_dev *dev = mdev->pci_dev;
 	u8 bar;
@@ -87,6 +88,9 @@ vp_modern_map_capability(struct virtio_pci_modern_device *mdev, int off,
 		dev_err(&dev->dev,
 			"virtio_pci: unable to map virtio %u@%u on bar %i\n",
 			length, offset, bar);
+	else if (pa)
+		*pa = pci_resource_start(dev, bar) + offset;
+
 	return p;
 }
 
@@ -273,12 +277,12 @@ int vp_modern_probe(struct virtio_pci_modern_device *mdev)
 	mdev->common = vp_modern_map_capability(mdev, common,
 				      sizeof(struct virtio_pci_common_cfg), 4,
 				      0, sizeof(struct virtio_pci_common_cfg),
-				      NULL);
+				      NULL, NULL);
 	if (!mdev->common)
 		goto err_map_common;
 	mdev->isr = vp_modern_map_capability(mdev, isr, sizeof(u8), 1,
 					     0, 1,
-					     NULL);
+					     NULL, NULL);
 	if (!mdev->isr)
 		goto err_map_isr;
 
@@ -306,7 +310,8 @@ int vp_modern_probe(struct virtio_pci_modern_device *mdev)
 		mdev->notify_base = vp_modern_map_capability(mdev, notify,
 							     2, 2,
 							     0, notify_length,
-							     &mdev->notify_len);
+							     &mdev->notify_len,
+							     &mdev->notify_pa);
 		if (!mdev->notify_base)
 			goto err_map_notify;
 	} else {
@@ -319,7 +324,8 @@ int vp_modern_probe(struct virtio_pci_modern_device *mdev)
 	if (device) {
 		mdev->device = vp_modern_map_capability(mdev, device, 0, 4,
 							0, PAGE_SIZE,
-							&mdev->device_len);
+							&mdev->device_len,
+							NULL);
 		if (!mdev->device)
 			goto err_map_device;
 	}
@@ -595,11 +601,12 @@ static u16 vp_modern_get_queue_notify_off(struct virtio_pci_modern_device *mdev,
  * specific virtqueue
  * @mdev: the modern virtio-pci device
  * @index: the queue index
+ * @pa: the pointer to the physical address of the nofity area
  *
  * Returns the address of the notification area
  */
 void *vp_modern_map_vq_notify(struct virtio_pci_modern_device *mdev,
-			      u16 index)
+			      u16 index, resource_size_t *pa)
 {
 	u16 off = vp_modern_get_queue_notify_off(mdev, index);
 
@@ -614,13 +621,16 @@ void *vp_modern_map_vq_notify(struct virtio_pci_modern_device *mdev,
 				 index, mdev->notify_len);
 			return NULL;
 		}
+		if (pa)
+			*pa = mdev->notify_pa +
+			      off * mdev->notify_offset_multiplier;
 		return (void __force *)mdev->notify_base +
 			off * mdev->notify_offset_multiplier;
 	} else {
 		return (void __force *)vp_modern_map_capability(mdev,
 				       mdev->notify_map_cap, 2, 2,
 				       off * mdev->notify_offset_multiplier, 2,
-				       NULL);
+				       NULL, pa);
 	}
 }
 EXPORT_SYMBOL_GPL(vp_modern_map_vq_notify);
diff --git a/include/linux/virtio_pci_modern.h b/include/linux/virtio_pci_modern.h
index e6e7072413c1..cdfabbefacdf 100644
--- a/include/linux/virtio_pci_modern.h
+++ b/include/linux/virtio_pci_modern.h
@@ -13,6 +13,8 @@ struct virtio_pci_modern_device {
 	void __iomem *device;
 	/* Base of vq notifications (non-legacy mode). */
 	void __iomem *notify_base;
+	/* Physical base of vq notifications */
+	resource_size_t notify_pa;
 	/* Where to read and clear interrupt */
 	u8 __iomem *isr;
 
@@ -100,7 +102,7 @@ u16 vp_modern_get_queue_size(struct virtio_pci_modern_device *mdev,
 			     u16 idx);
 u16 vp_modern_get_num_queues(struct virtio_pci_modern_device *mdev);
 void *vp_modern_map_vq_notify(struct virtio_pci_modern_device *mdev,
-                              u16 index);
+                              u16 index, resource_size_t *pa);
 int vp_modern_probe(struct virtio_pci_modern_device *mdev);
 void vp_modern_remove(struct virtio_pci_modern_device *mdev);
 #endif
-- 
2.18.1

[PATCH 7/7] vp_vdpa: report doorbell address

[Jason Wang]

This patch reports the per vq doorbell location and size to vDPA
bus. Userspace can then map the doorbell via mmap() via vhost-vDPA bus
driver.

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 drivers/vdpa/virtio_pci/vp_vdpa.c | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c b/drivers/vdpa/virtio_pci/vp_vdpa.c
index 98205e54d089..002b928d0ca1 100644
--- a/drivers/vdpa/virtio_pci/vp_vdpa.c
+++ b/drivers/vdpa/virtio_pci/vp_vdpa.c
@@ -26,6 +26,7 @@ struct vp_vring {
 	void __iomem *notify;
 	char msix_name[VP_VDPA_NAME_SIZE];
 	struct vdpa_callback cb;
+	resource_size_t notify_pa;
 	int irq;
 };
 
@@ -336,6 +337,19 @@ static void vp_vdpa_set_config_cb(struct vdpa_device *vdpa,
 	vp_vdpa->config_cb = *cb;
 }
 
+static struct vdpa_notification_area
+vp_vdpa_get_vq_notification(struct vdpa_device *vdpa, u16 qid)
+{
+	struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
+	struct virtio_pci_modern_device *mdev = &vp_vdpa->mdev;
+	struct vdpa_notification_area notify;
+
+	notify.addr = vp_vdpa->vring[qid].notify_pa;
+	notify.size = mdev->notify_offset_multiplier;
+
+	return notify;
+}
+
 static const struct vdpa_config_ops vp_vdpa_ops = {
 	.get_features	= vp_vdpa_get_features,
 	.set_features	= vp_vdpa_set_features,
@@ -343,6 +357,7 @@ static const struct vdpa_config_ops vp_vdpa_ops = {
 	.set_status	= vp_vdpa_set_status,
 	.get_vq_num_max	= vp_vdpa_get_vq_num_max,
 	.get_vq_state	= vp_vdpa_get_vq_state,
+	.get_vq_notification = vp_vdpa_get_vq_notification,
 	.set_vq_state	= vp_vdpa_set_vq_state,
 	.set_vq_cb	= vp_vdpa_set_vq_cb,
 	.set_vq_ready	= vp_vdpa_set_vq_ready,
@@ -416,7 +431,8 @@ static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	for (i = 0; i < vp_vdpa->queues; i++) {
 		vp_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
 		vp_vdpa->vring[i].notify =
-			vp_modern_map_vq_notify(mdev, i, NULL);
+			vp_modern_map_vq_notify(mdev, i,
+						&vp_vdpa->vring[i].notify_pa);
 		if (!vp_vdpa->vring[i].notify) {
 			dev_warn(&pdev->dev, "Fail to map vq notify %d\n", i);
 			goto err;
-- 
2.18.1

Re: [PATCH 7/7] vp_vdpa: report doorbell address

[Eli Cohen]

On Thu, Apr 15, 2021 at 03:31:47AM -0400, Jason Wang wrote:
> This patch reports the per vq doorbell location and size to vDPA
> bus. Userspace can then map the doorbell via mmap() via vhost-vDPA bus
> driver.
> 
> Signed-off-by: Jason Wang <jasowang@redhat.com>

Reviewed-by: Eli Cohen <elic@nvidia.com>

> ---
>  drivers/vdpa/virtio_pci/vp_vdpa.c | 18 +++++++++++++++++-
>  1 file changed, 17 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c b/drivers/vdpa/virtio_pci/vp_vdpa.c
> index 98205e54d089..002b928d0ca1 100644
> --- a/drivers/vdpa/virtio_pci/vp_vdpa.c
> +++ b/drivers/vdpa/virtio_pci/vp_vdpa.c
> @@ -26,6 +26,7 @@ struct vp_vring {
>  	void __iomem *notify;
>  	char msix_name[VP_VDPA_NAME_SIZE];
>  	struct vdpa_callback cb;
> +	resource_size_t notify_pa;
>  	int irq;
>  };
>  
> @@ -336,6 +337,19 @@ static void vp_vdpa_set_config_cb(struct vdpa_device *vdpa,
>  	vp_vdpa->config_cb = *cb;
>  }
>  
> +static struct vdpa_notification_area
> +vp_vdpa_get_vq_notification(struct vdpa_device *vdpa, u16 qid)
> +{
> +	struct vp_vdpa *vp_vdpa = vdpa_to_vp(vdpa);
> +	struct virtio_pci_modern_device *mdev = &vp_vdpa->mdev;
> +	struct vdpa_notification_area notify;
> +
> +	notify.addr = vp_vdpa->vring[qid].notify_pa;
> +	notify.size = mdev->notify_offset_multiplier;
> +
> +	return notify;
> +}
> +
>  static const struct vdpa_config_ops vp_vdpa_ops = {
>  	.get_features	= vp_vdpa_get_features,
>  	.set_features	= vp_vdpa_set_features,
> @@ -343,6 +357,7 @@ static const struct vdpa_config_ops vp_vdpa_ops = {
>  	.set_status	= vp_vdpa_set_status,
>  	.get_vq_num_max	= vp_vdpa_get_vq_num_max,
>  	.get_vq_state	= vp_vdpa_get_vq_state,
> +	.get_vq_notification = vp_vdpa_get_vq_notification,
>  	.set_vq_state	= vp_vdpa_set_vq_state,
>  	.set_vq_cb	= vp_vdpa_set_vq_cb,
>  	.set_vq_ready	= vp_vdpa_set_vq_ready,
> @@ -416,7 +431,8 @@ static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id)
>  	for (i = 0; i < vp_vdpa->queues; i++) {
>  		vp_vdpa->vring[i].irq = VIRTIO_MSI_NO_VECTOR;
>  		vp_vdpa->vring[i].notify =
> -			vp_modern_map_vq_notify(mdev, i, NULL);
> +			vp_modern_map_vq_notify(mdev, i,
> +						&vp_vdpa->vring[i].notify_pa);
>  		if (!vp_vdpa->vring[i].notify) {
>  			dev_warn(&pdev->dev, "Fail to map vq notify %d\n", i);
>  			goto err;
> -- 
> 2.18.1
>