summaryrefslogtreecommitdiff
path: root/drivers/vfio
diff options
context:
space:
mode:
authorYi Liu <yi.l.liu@intel.com>2023-03-27 02:33:50 -0700
committerJason Gunthorpe <jgg@nvidia.com>2023-03-31 13:43:32 -0300
commit0a782d15e1d406e8074954405b1dc143a7645344 (patch)
tree29523857f6f4a91c485701c4bb225fdab21c7fc9 /drivers/vfio
parent632fda7f912c845f98ff20e69c600160a189d803 (diff)
downloadlwn-0a782d15e1d406e8074954405b1dc143a7645344.tar.gz
lwn-0a782d15e1d406e8074954405b1dc143a7645344.zip
vfio/mdev: Uses the vfio emulated iommufd ops set in the mdev sample drivers
This harmonizes the no-DMA devices (the vfio-mdev sample drivers) with the emulated devices (gvt-g, vfio-ap etc.). It makes it easier to add BIND_IOMMUFD user interface which requires to return an iommufd ID to represent the device/iommufd bond. Link: https://lore.kernel.org/r/20230327093351.44505-6-yi.l.liu@intel.com Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Tested-by: Terrence Xu <terrence.xu@intel.com> Tested-by: Nicolin Chen <nicolinc@nvidia.com> Signed-off-by: Yi Liu <yi.l.liu@intel.com> Acked-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Diffstat (limited to 'drivers/vfio')
-rw-r--r--drivers/vfio/iommufd.c14
1 files changed, 6 insertions, 8 deletions
diff --git a/drivers/vfio/iommufd.c b/drivers/vfio/iommufd.c
index 1ee558c0be25..890ea101685c 100644
--- a/drivers/vfio/iommufd.c
+++ b/drivers/vfio/iommufd.c
@@ -32,12 +32,8 @@ int vfio_iommufd_bind(struct vfio_device *vdev, struct iommufd_ctx *ictx)
return 0;
}
- /*
- * If the driver doesn't provide this op then it means the device does
- * not do DMA at all. So nothing to do.
- */
- if (!vdev->ops->bind_iommufd)
- return 0;
+ if (WARN_ON(!vdev->ops->bind_iommufd))
+ return -ENODEV;
ret = vdev->ops->bind_iommufd(vdev, ictx, &device_id);
if (ret)
@@ -119,7 +115,8 @@ EXPORT_SYMBOL_GPL(vfio_iommufd_physical_attach_ioas);
/*
* The emulated standard ops mean that vfio_device is going to use the
* "mdev path" and will call vfio_pin_pages()/vfio_dma_rw(). Drivers using this
- * ops set should call vfio_register_emulated_iommu_dev().
+ * ops set should call vfio_register_emulated_iommu_dev(). Drivers that do
+ * not call vfio_pin_pages()/vfio_dma_rw() have no need to provide dma_unmap.
*/
static void vfio_emulated_unmap(void *data, unsigned long iova,
@@ -127,7 +124,8 @@ static void vfio_emulated_unmap(void *data, unsigned long iova,
{
struct vfio_device *vdev = data;
- vdev->ops->dma_unmap(vdev, iova, length);
+ if (vdev->ops->dma_unmap)
+ vdev->ops->dma_unmap(vdev, iova, length);
}
static const struct iommufd_access_ops vfio_user_ops = {