vfio: Add VFIO_DEVICE_BIND_IOMMUFD

This adds ioctl for userspace to bind device cdev fd to iommufd.

    VFIO_DEVICE_BIND_IOMMUFD: bind device to an iommufd, hence gain DMA
			      control provided by the iommufd. open_device
			      op is called after bind_iommufd op.

Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Tested-by: Yanting Jiang <yanting.jiang@intel.com>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Tested-by: Terrence Xu <terrence.xu@intel.com>
Tested-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20230718135551.6592-23-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

1 files changed, 13 insertions, 0 deletions

diff --git a/drivers/vfio/vfio.h b/drivers/vfio/vfio.h
index c2aa65382592..b6d4ba1ef2b8 100644
--- a/drivers/vfio/vfio.h
+++ b/drivers/vfio/vfio.h
@@ -287,6 +287,9 @@ static inline void vfio_device_del(struct vfio_device *device)
 }
 
 int vfio_device_fops_cdev_open(struct inode *inode, struct file *filep);
+long vfio_df_ioctl_bind_iommufd(struct vfio_device_file *df,
+				struct vfio_device_bind_iommufd __user *arg);
+void vfio_df_unbind_iommufd(struct vfio_device_file *df);
 int vfio_cdev_init(struct class *device_class);
 void vfio_cdev_cleanup(void);
 #else
@@ -310,6 +313,16 @@ static inline int vfio_device_fops_cdev_open(struct inode *inode,
 	return 0;
 }
 
+static inline long vfio_df_ioctl_bind_iommufd(struct vfio_device_file *df,
+					      struct vfio_device_bind_iommufd __user *arg)
+{
+	return -ENOTTY;
+}
+
+static inline void vfio_df_unbind_iommufd(struct vfio_device_file *df)
+{
+}
+
 static inline int vfio_cdev_init(struct class *device_class)
 {
 	return 0;