diff mbox series

[v2,3/7] vfio/mdev: Pass in a struct vfio_device * to vfio_pin/unpin_pages()

Message ID 3-v2-6011bde8e0a1+5f-vfio_mdev_no_group_jgg@nvidia.com (mailing list archive)
State New, archived
Headers show
Series Make the rest of the VFIO driver interface use vfio_device | expand

Commit Message

Jason Gunthorpe April 21, 2022, 4:28 p.m. UTC 
Every caller has a readily available vfio_device pointer, use that instead
of passing in a generic struct device. The struct vfio_device already
contains the group we need so this avoids complexity, extra refcountings,
and a confusing lifecycle model.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com>
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
---
 .../driver-api/vfio-mediated-device.rst       |  4 +-
 drivers/s390/cio/vfio_ccw_cp.c                |  6 +--
 drivers/s390/crypto/vfio_ap_ops.c             |  9 ++---
 drivers/vfio/vfio.c                           | 40 ++++++-------------
 include/linux/vfio.h                          |  4 +-
 5 files changed, 24 insertions(+), 39 deletions(-)

Comments

Tian, Kevin April 22, 2022, 1:43 a.m. UTC | #1 
> From: Jason Gunthorpe <jgg@nvidia.com>
> Sent: Friday, April 22, 2022 12:29 AM
> 
> Every caller has a readily available vfio_device pointer, use that instead
> of passing in a generic struct device. The struct vfio_device already
> contains the group we need so this avoids complexity, extra refcountings,
> and a confusing lifecycle model.
> 
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> Acked-by: Eric Farman <farman@linux.ibm.com>
> Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com>
> Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

Reviewed-by: Kevin Tian <kevin.tian@intel.com>

> ---
>  .../driver-api/vfio-mediated-device.rst       |  4 +-
>  drivers/s390/cio/vfio_ccw_cp.c                |  6 +--
>  drivers/s390/crypto/vfio_ap_ops.c             |  9 ++---
>  drivers/vfio/vfio.c                           | 40 ++++++-------------
>  include/linux/vfio.h                          |  4 +-
>  5 files changed, 24 insertions(+), 39 deletions(-)
> 
> diff --git a/Documentation/driver-api/vfio-mediated-device.rst
> b/Documentation/driver-api/vfio-mediated-device.rst
> index 784bbeb22adcf5..2f9e6025eb2fe1 100644
> --- a/Documentation/driver-api/vfio-mediated-device.rst
> +++ b/Documentation/driver-api/vfio-mediated-device.rst
> @@ -262,10 +262,10 @@ Translation APIs for Mediated Devices
>  The following APIs are provided for translating user pfn to host pfn in a VFIO
>  driver::
> 
> -	extern int vfio_pin_pages(struct device *dev, unsigned long
> *user_pfn,
> +	int vfio_pin_pages(struct vfio_device *vdev, unsigned long *user_pfn,
>  				  int npage, int prot, unsigned long
> *phys_pfn);
> 
> -	extern int vfio_unpin_pages(struct device *dev, unsigned long
> *user_pfn,
> +	int vfio_unpin_pages(struct vfio_device *vdev, unsigned long
> *user_pfn,
>  				    int npage);
> 
>  These functions call back into the back-end IOMMU module by using the
> pin_pages
> diff --git a/drivers/s390/cio/vfio_ccw_cp.c b/drivers/s390/cio/vfio_ccw_cp.c
> index 7a1cf3091cd647..0c2be9421ab78f 100644
> --- a/drivers/s390/cio/vfio_ccw_cp.c
> +++ b/drivers/s390/cio/vfio_ccw_cp.c
> @@ -103,13 +103,13 @@ static int pfn_array_pin(struct pfn_array *pa,
> struct vfio_device *vdev)
>  {
>  	int ret = 0;
> 
> -	ret = vfio_pin_pages(vdev->dev, pa->pa_iova_pfn, pa->pa_nr,
> +	ret = vfio_pin_pages(vdev, pa->pa_iova_pfn, pa->pa_nr,
>  			     IOMMU_READ | IOMMU_WRITE, pa->pa_pfn);
> 
>  	if (ret < 0) {
>  		goto err_out;
>  	} else if (ret > 0 && ret != pa->pa_nr) {
> -		vfio_unpin_pages(vdev->dev, pa->pa_iova_pfn, ret);
> +		vfio_unpin_pages(vdev, pa->pa_iova_pfn, ret);
>  		ret = -EINVAL;
>  		goto err_out;
>  	}
> @@ -127,7 +127,7 @@ static void pfn_array_unpin_free(struct pfn_array
> *pa, struct vfio_device *vdev)
>  {
>  	/* Only unpin if any pages were pinned to begin with */
>  	if (pa->pa_nr)
> -		vfio_unpin_pages(vdev->dev, pa->pa_iova_pfn, pa->pa_nr);
> +		vfio_unpin_pages(vdev, pa->pa_iova_pfn, pa->pa_nr);
>  	pa->pa_nr = 0;
>  	kfree(pa->pa_iova_pfn);
>  }
> diff --git a/drivers/s390/crypto/vfio_ap_ops.c
> b/drivers/s390/crypto/vfio_ap_ops.c
> index bfa7ee6ef532d9..e8914024f5b1af 100644
> --- a/drivers/s390/crypto/vfio_ap_ops.c
> +++ b/drivers/s390/crypto/vfio_ap_ops.c
> @@ -124,8 +124,7 @@ static void vfio_ap_free_aqic_resources(struct
> vfio_ap_queue *q)
>  		q->saved_isc = VFIO_AP_ISC_INVALID;
>  	}
>  	if (q->saved_pfn && !WARN_ON(!q->matrix_mdev)) {
> -		vfio_unpin_pages(mdev_dev(q->matrix_mdev->mdev),
> -				 &q->saved_pfn, 1);
> +		vfio_unpin_pages(&q->matrix_mdev->vdev, &q->saved_pfn,
> 1);
>  		q->saved_pfn = 0;
>  	}
>  }
> @@ -258,7 +257,7 @@ static struct ap_queue_status
> vfio_ap_irq_enable(struct vfio_ap_queue *q,
>  		return status;
>  	}
> 
> -	ret = vfio_pin_pages(mdev_dev(q->matrix_mdev->mdev), &g_pfn, 1,
> +	ret = vfio_pin_pages(&q->matrix_mdev->vdev, &g_pfn, 1,
>  			     IOMMU_READ | IOMMU_WRITE, &h_pfn);
>  	switch (ret) {
>  	case 1:
> @@ -301,7 +300,7 @@ static struct ap_queue_status
> vfio_ap_irq_enable(struct vfio_ap_queue *q,
>  		break;
>  	case AP_RESPONSE_OTHERWISE_CHANGED:
>  		/* We could not modify IRQ setings: clear new configuration
> */
> -		vfio_unpin_pages(mdev_dev(q->matrix_mdev->mdev),
> &g_pfn, 1);
> +		vfio_unpin_pages(&q->matrix_mdev->vdev, &g_pfn, 1);
>  		kvm_s390_gisc_unregister(kvm, isc);
>  		break;
>  	default:
> @@ -1250,7 +1249,7 @@ static int vfio_ap_mdev_iommu_notifier(struct
> notifier_block *nb,
>  		struct vfio_iommu_type1_dma_unmap *unmap = data;
>  		unsigned long g_pfn = unmap->iova >> PAGE_SHIFT;
> 
> -		vfio_unpin_pages(mdev_dev(matrix_mdev->mdev), &g_pfn,
> 1);
> +		vfio_unpin_pages(&matrix_mdev->vdev, &g_pfn, 1);
>  		return NOTIFY_OK;
>  	}
> 
> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
> index 8a5c46aa2bef61..24b92a45cfc8f1 100644
> --- a/drivers/vfio/vfio.c
> +++ b/drivers/vfio/vfio.c
> @@ -2142,32 +2142,26 @@
> EXPORT_SYMBOL(vfio_set_irqs_validate_and_prepare);
>   * @phys_pfn[out]: array of host PFNs
>   * Return error or number of pages pinned.
>   */
> -int vfio_pin_pages(struct device *dev, unsigned long *user_pfn, int npage,
> +int vfio_pin_pages(struct vfio_device *vdev, unsigned long *user_pfn, int
> npage,
>  		   int prot, unsigned long *phys_pfn)
>  {
>  	struct vfio_container *container;
> -	struct vfio_group *group;
> +	struct vfio_group *group = vdev->group;
>  	struct vfio_iommu_driver *driver;
>  	int ret;
> 
> -	if (!dev || !user_pfn || !phys_pfn || !npage)
> +	if (!user_pfn || !phys_pfn || !npage)
>  		return -EINVAL;
> 
>  	if (npage > VFIO_PIN_PAGES_MAX_ENTRIES)
>  		return -E2BIG;
> 
> -	group = vfio_group_get_from_dev(dev);
> -	if (!group)
> -		return -ENODEV;
> -
> -	if (group->dev_counter > 1) {
> -		ret = -EINVAL;
> -		goto err_pin_pages;
> -	}
> +	if (group->dev_counter > 1)
> +		return -EINVAL;
> 
>  	ret = vfio_group_add_container_user(group);
>  	if (ret)
> -		goto err_pin_pages;
> +		return ret;
> 
>  	container = group->container;
>  	driver = container->iommu_driver;
> @@ -2180,8 +2174,6 @@ int vfio_pin_pages(struct device *dev, unsigned
> long *user_pfn, int npage,
> 
>  	vfio_group_try_dissolve_container(group);
> 
> -err_pin_pages:
> -	vfio_group_put(group);
>  	return ret;
>  }
>  EXPORT_SYMBOL(vfio_pin_pages);
> @@ -2195,28 +2187,24 @@ EXPORT_SYMBOL(vfio_pin_pages);
>   *                 be greater than VFIO_PIN_PAGES_MAX_ENTRIES.
>   * Return error or number of pages unpinned.
>   */
> -int vfio_unpin_pages(struct device *dev, unsigned long *user_pfn, int npage)
> +int vfio_unpin_pages(struct vfio_device *vdev, unsigned long *user_pfn,
> +		     int npage)
>  {
>  	struct vfio_container *container;
> -	struct vfio_group *group;
>  	struct vfio_iommu_driver *driver;
>  	int ret;
> 
> -	if (!dev || !user_pfn || !npage)
> +	if (!user_pfn || !npage)
>  		return -EINVAL;
> 
>  	if (npage > VFIO_PIN_PAGES_MAX_ENTRIES)
>  		return -E2BIG;
> 
> -	group = vfio_group_get_from_dev(dev);
> -	if (!group)
> -		return -ENODEV;
> -
> -	ret = vfio_group_add_container_user(group);
> +	ret = vfio_group_add_container_user(vdev->group);
>  	if (ret)
> -		goto err_unpin_pages;
> +		return ret;
> 
> -	container = group->container;
> +	container = vdev->group->container;
>  	driver = container->iommu_driver;
>  	if (likely(driver && driver->ops->unpin_pages))
>  		ret = driver->ops->unpin_pages(container->iommu_data,
> user_pfn,
> @@ -2224,10 +2212,8 @@ int vfio_unpin_pages(struct device *dev,
> unsigned long *user_pfn, int npage)
>  	else
>  		ret = -ENOTTY;
> 
> -	vfio_group_try_dissolve_container(group);
> +	vfio_group_try_dissolve_container(vdev->group);
> 
> -err_unpin_pages:
> -	vfio_group_put(group);
>  	return ret;
>  }
>  EXPORT_SYMBOL(vfio_unpin_pages);
> diff --git a/include/linux/vfio.h b/include/linux/vfio.h
> index 748ec0e0293aea..8f2a09801a660b 100644
> --- a/include/linux/vfio.h
> +++ b/include/linux/vfio.h
> @@ -150,9 +150,9 @@ extern long vfio_external_check_extension(struct
> vfio_group *group,
> 
>  #define VFIO_PIN_PAGES_MAX_ENTRIES	(PAGE_SIZE/sizeof(unsigned
> long))
> 
> -extern int vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
> +extern int vfio_pin_pages(struct vfio_device *vdev, unsigned long *user_pfn,
>  			  int npage, int prot, unsigned long *phys_pfn);
> -extern int vfio_unpin_pages(struct device *dev, unsigned long *user_pfn,
> +extern int vfio_unpin_pages(struct vfio_device *vdev, unsigned long
> *user_pfn,
>  			    int npage);
> 
>  extern int vfio_group_pin_pages(struct vfio_group *group,
> --
> 2.36.0
Christoph Hellwig April 22, 2022, 6:22 a.m. UTC | #2 
Nit: why do some of these patches that don't touch the mdev code
mdev in the subject?
Jason Gunthorpe April 22, 2022, 8:56 p.m. UTC | #3 
On Fri, Apr 22, 2022 at 08:22:32AM +0200, Christoph Hellwig wrote:
> Nit: why do some of these patches that don't touch the mdev code
> mdev in the subject?

I consider these APIs to be 'mdev apis' because only mdev drivers
should call them.

Jason
Christoph Hellwig April 23, 2022, 5:15 a.m. UTC | #4 
On Fri, Apr 22, 2022 at 05:56:51PM -0300, Jason Gunthorpe wrote:
> On Fri, Apr 22, 2022 at 08:22:32AM +0200, Christoph Hellwig wrote:
> > Nit: why do some of these patches that don't touch the mdev code
> > mdev in the subject?
> 
> I consider these APIs to be 'mdev apis' because only mdev drivers
> should call them.

I thought we settled on 'emulated IOMMU device' in the VFIO core for
them, leaving mdev just for the odd lifecycle management glue.
Jason Gunthorpe April 23, 2022, 12:49 p.m. UTC | #5 
On Sat, Apr 23, 2022 at 07:15:52AM +0200, Christoph Hellwig wrote:
> On Fri, Apr 22, 2022 at 05:56:51PM -0300, Jason Gunthorpe wrote:
> > On Fri, Apr 22, 2022 at 08:22:32AM +0200, Christoph Hellwig wrote:
> > > Nit: why do some of these patches that don't touch the mdev code
> > > mdev in the subject?
> > 
> > I consider these APIs to be 'mdev apis' because only mdev drivers
> > should call them.
> 
> I thought we settled on 'emulated IOMMU device' in the VFIO core for
> them, leaving mdev just for the odd lifecycle management glue.

Yes

vfio/emulated

?

Jason
diff mbox series

Patch

diff --git a/Documentation/driver-api/vfio-mediated-device.rst b/Documentation/driver-api/vfio-mediated-device.rst
index 784bbeb22adcf5..2f9e6025eb2fe1 100644
--- a/Documentation/driver-api/vfio-mediated-device.rst
+++ b/Documentation/driver-api/vfio-mediated-device.rst
@@ -262,10 +262,10 @@  Translation APIs for Mediated Devices
 The following APIs are provided for translating user pfn to host pfn in a VFIO
 driver::
 
-	extern int vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
+	int vfio_pin_pages(struct vfio_device *vdev, unsigned long *user_pfn,
 				  int npage, int prot, unsigned long *phys_pfn);
 
-	extern int vfio_unpin_pages(struct device *dev, unsigned long *user_pfn,
+	int vfio_unpin_pages(struct vfio_device *vdev, unsigned long *user_pfn,
 				    int npage);
 
 These functions call back into the back-end IOMMU module by using the pin_pages
diff --git a/drivers/s390/cio/vfio_ccw_cp.c b/drivers/s390/cio/vfio_ccw_cp.c
index 7a1cf3091cd647..0c2be9421ab78f 100644
--- a/drivers/s390/cio/vfio_ccw_cp.c
+++ b/drivers/s390/cio/vfio_ccw_cp.c
@@ -103,13 +103,13 @@  static int pfn_array_pin(struct pfn_array *pa, struct vfio_device *vdev)
 {
 	int ret = 0;
 
-	ret = vfio_pin_pages(vdev->dev, pa->pa_iova_pfn, pa->pa_nr,
+	ret = vfio_pin_pages(vdev, pa->pa_iova_pfn, pa->pa_nr,
 			     IOMMU_READ | IOMMU_WRITE, pa->pa_pfn);
 
 	if (ret < 0) {
 		goto err_out;
 	} else if (ret > 0 && ret != pa->pa_nr) {
-		vfio_unpin_pages(vdev->dev, pa->pa_iova_pfn, ret);
+		vfio_unpin_pages(vdev, pa->pa_iova_pfn, ret);
 		ret = -EINVAL;
 		goto err_out;
 	}
@@ -127,7 +127,7 @@  static void pfn_array_unpin_free(struct pfn_array *pa, struct vfio_device *vdev)
 {
 	/* Only unpin if any pages were pinned to begin with */
 	if (pa->pa_nr)
-		vfio_unpin_pages(vdev->dev, pa->pa_iova_pfn, pa->pa_nr);
+		vfio_unpin_pages(vdev, pa->pa_iova_pfn, pa->pa_nr);
 	pa->pa_nr = 0;
 	kfree(pa->pa_iova_pfn);
 }
diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
index bfa7ee6ef532d9..e8914024f5b1af 100644
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -124,8 +124,7 @@  static void vfio_ap_free_aqic_resources(struct vfio_ap_queue *q)
 		q->saved_isc = VFIO_AP_ISC_INVALID;
 	}
 	if (q->saved_pfn && !WARN_ON(!q->matrix_mdev)) {
-		vfio_unpin_pages(mdev_dev(q->matrix_mdev->mdev),
-				 &q->saved_pfn, 1);
+		vfio_unpin_pages(&q->matrix_mdev->vdev, &q->saved_pfn, 1);
 		q->saved_pfn = 0;
 	}
 }
@@ -258,7 +257,7 @@  static struct ap_queue_status vfio_ap_irq_enable(struct vfio_ap_queue *q,
 		return status;
 	}
 
-	ret = vfio_pin_pages(mdev_dev(q->matrix_mdev->mdev), &g_pfn, 1,
+	ret = vfio_pin_pages(&q->matrix_mdev->vdev, &g_pfn, 1,
 			     IOMMU_READ | IOMMU_WRITE, &h_pfn);
 	switch (ret) {
 	case 1:
@@ -301,7 +300,7 @@  static struct ap_queue_status vfio_ap_irq_enable(struct vfio_ap_queue *q,
 		break;
 	case AP_RESPONSE_OTHERWISE_CHANGED:
 		/* We could not modify IRQ setings: clear new configuration */
-		vfio_unpin_pages(mdev_dev(q->matrix_mdev->mdev), &g_pfn, 1);
+		vfio_unpin_pages(&q->matrix_mdev->vdev, &g_pfn, 1);
 		kvm_s390_gisc_unregister(kvm, isc);
 		break;
 	default:
@@ -1250,7 +1249,7 @@  static int vfio_ap_mdev_iommu_notifier(struct notifier_block *nb,
 		struct vfio_iommu_type1_dma_unmap *unmap = data;
 		unsigned long g_pfn = unmap->iova >> PAGE_SHIFT;
 
-		vfio_unpin_pages(mdev_dev(matrix_mdev->mdev), &g_pfn, 1);
+		vfio_unpin_pages(&matrix_mdev->vdev, &g_pfn, 1);
 		return NOTIFY_OK;
 	}
 
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index 8a5c46aa2bef61..24b92a45cfc8f1 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -2142,32 +2142,26 @@  EXPORT_SYMBOL(vfio_set_irqs_validate_and_prepare);
  * @phys_pfn[out]: array of host PFNs
  * Return error or number of pages pinned.
  */
-int vfio_pin_pages(struct device *dev, unsigned long *user_pfn, int npage,
+int vfio_pin_pages(struct vfio_device *vdev, unsigned long *user_pfn, int npage,
 		   int prot, unsigned long *phys_pfn)
 {
 	struct vfio_container *container;
-	struct vfio_group *group;
+	struct vfio_group *group = vdev->group;
 	struct vfio_iommu_driver *driver;
 	int ret;
 
-	if (!dev || !user_pfn || !phys_pfn || !npage)
+	if (!user_pfn || !phys_pfn || !npage)
 		return -EINVAL;
 
 	if (npage > VFIO_PIN_PAGES_MAX_ENTRIES)
 		return -E2BIG;
 
-	group = vfio_group_get_from_dev(dev);
-	if (!group)
-		return -ENODEV;
-
-	if (group->dev_counter > 1) {
-		ret = -EINVAL;
-		goto err_pin_pages;
-	}
+	if (group->dev_counter > 1)
+		return -EINVAL;
 
 	ret = vfio_group_add_container_user(group);
 	if (ret)
-		goto err_pin_pages;
+		return ret;
 
 	container = group->container;
 	driver = container->iommu_driver;
@@ -2180,8 +2174,6 @@  int vfio_pin_pages(struct device *dev, unsigned long *user_pfn, int npage,
 
 	vfio_group_try_dissolve_container(group);
 
-err_pin_pages:
-	vfio_group_put(group);
 	return ret;
 }
 EXPORT_SYMBOL(vfio_pin_pages);
@@ -2195,28 +2187,24 @@  EXPORT_SYMBOL(vfio_pin_pages);
  *                 be greater than VFIO_PIN_PAGES_MAX_ENTRIES.
  * Return error or number of pages unpinned.
  */
-int vfio_unpin_pages(struct device *dev, unsigned long *user_pfn, int npage)
+int vfio_unpin_pages(struct vfio_device *vdev, unsigned long *user_pfn,
+		     int npage)
 {
 	struct vfio_container *container;
-	struct vfio_group *group;
 	struct vfio_iommu_driver *driver;
 	int ret;
 
-	if (!dev || !user_pfn || !npage)
+	if (!user_pfn || !npage)
 		return -EINVAL;
 
 	if (npage > VFIO_PIN_PAGES_MAX_ENTRIES)
 		return -E2BIG;
 
-	group = vfio_group_get_from_dev(dev);
-	if (!group)
-		return -ENODEV;
-
-	ret = vfio_group_add_container_user(group);
+	ret = vfio_group_add_container_user(vdev->group);
 	if (ret)
-		goto err_unpin_pages;
+		return ret;
 
-	container = group->container;
+	container = vdev->group->container;
 	driver = container->iommu_driver;
 	if (likely(driver && driver->ops->unpin_pages))
 		ret = driver->ops->unpin_pages(container->iommu_data, user_pfn,
@@ -2224,10 +2212,8 @@  int vfio_unpin_pages(struct device *dev, unsigned long *user_pfn, int npage)
 	else
 		ret = -ENOTTY;
 
-	vfio_group_try_dissolve_container(group);
+	vfio_group_try_dissolve_container(vdev->group);
 
-err_unpin_pages:
-	vfio_group_put(group);
 	return ret;
 }
 EXPORT_SYMBOL(vfio_unpin_pages);
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index 748ec0e0293aea..8f2a09801a660b 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -150,9 +150,9 @@  extern long vfio_external_check_extension(struct vfio_group *group,
 
 #define VFIO_PIN_PAGES_MAX_ENTRIES	(PAGE_SIZE/sizeof(unsigned long))
 
-extern int vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
+extern int vfio_pin_pages(struct vfio_device *vdev, unsigned long *user_pfn,
 			  int npage, int prot, unsigned long *phys_pfn);
-extern int vfio_unpin_pages(struct device *dev, unsigned long *user_pfn,
+extern int vfio_unpin_pages(struct vfio_device *vdev, unsigned long *user_pfn,
 			    int npage);
 
 extern int vfio_group_pin_pages(struct vfio_group *group,