[PATCH v9 14/25] vfio: Record devid in vfio_device_file

[Yi Liu <yi.l.liu@intel.com>]

.bind_iommufd() will generate an ID to represent this bond, which is
needed by userspace for further usage. Store devid in vfio_device_file
to avoid passing the pointer in multiple places.

Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Tested-by: Terrence Xu <terrence.xu@intel.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Yanting Jiang <yanting.jiang@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
---
 drivers/vfio/iommufd.c   | 12 +++++++-----
 drivers/vfio/vfio.h      | 10 +++++-----
 drivers/vfio/vfio_main.c |  6 +++---
 3 files changed, 15 insertions(+), 13 deletions(-)

diff --git a/drivers/vfio/iommufd.c b/drivers/vfio/iommufd.c
index 20fd250c247c..6ef9316a16a5 100644
--- a/drivers/vfio/iommufd.c
+++ b/drivers/vfio/iommufd.c
@@ -28,14 +28,14 @@ int vfio_iommufd_enable_noiommu_compat(struct vfio_device *device,
 	return 0;
 }
 
-int vfio_iommufd_bind(struct vfio_device *vdev, struct iommufd_ctx *ictx)
+int vfio_iommufd_bind(struct vfio_device_file *df)
 {
-	u32 device_id;
+	struct vfio_device *vdev = df->device;
+	struct iommufd_ctx *ictx = df->iommufd;
 
 	lockdep_assert_held(&vdev->dev_set->lock);
 
-	/* The legacy path has no way to return the device id */
-	return vdev->ops->bind_iommufd(vdev, ictx, &device_id);
+	return vdev->ops->bind_iommufd(vdev, ictx, &df->devid);
 }
 
 int vfio_iommufd_attach_compat_ioas(struct vfio_device *vdev,
@@ -54,8 +54,10 @@ int vfio_iommufd_attach_compat_ioas(struct vfio_device *vdev,
 	return vdev->ops->attach_ioas(vdev, &ioas_id);
 }
 
-void vfio_iommufd_unbind(struct vfio_device *vdev)
+void vfio_iommufd_unbind(struct vfio_device_file *df)
 {
+	struct vfio_device *vdev = df->device;
+
 	lockdep_assert_held(&vdev->dev_set->lock);
 
 	if (vdev->ops->unbind_iommufd)
diff --git a/drivers/vfio/vfio.h b/drivers/vfio/vfio.h
index abfaf85cc266..b47b186573ac 100644
--- a/drivers/vfio/vfio.h
+++ b/drivers/vfio/vfio.h
@@ -24,6 +24,7 @@ struct vfio_device_file {
 	spinlock_t kvm_ref_lock; /* protect kvm field */
 	struct kvm *kvm;
 	struct iommufd_ctx *iommufd; /* protected by struct vfio_device_set::lock */
+	u32 devid; /* only valid when iommufd is valid */
 };
 
 void vfio_device_put_registration(struct vfio_device *device);
@@ -240,8 +241,8 @@ int vfio_iommufd_enable_noiommu_compat(struct vfio_device *device,
 				       struct iommufd_ctx *ictx);
 int vfio_iommufd_attach_compat_ioas(struct vfio_device *device,
 				    struct iommufd_ctx *ictx);
-int vfio_iommufd_bind(struct vfio_device *device, struct iommufd_ctx *ictx);
-void vfio_iommufd_unbind(struct vfio_device *device);
+int vfio_iommufd_bind(struct vfio_device_file *df);
+void vfio_iommufd_unbind(struct vfio_device_file *df);
 #else
 static inline int
 vfio_iommufd_enable_noiommu_compat(struct vfio_device *device,
@@ -257,13 +258,12 @@ vfio_iommufd_attach_compat_ioas(struct vfio_device *device,
 	return -EOPNOTSUPP;
 }
 
-static inline int vfio_iommufd_bind(struct vfio_device *device,
-				    struct iommufd_ctx *ictx)
+static inline int vfio_iommufd_bind(struct vfio_device_file *df)
 {
 	return -EOPNOTSUPP;
 }
 
-static inline void vfio_iommufd_unbind(struct vfio_device *device)
+static inline void vfio_iommufd_unbind(struct vfio_device_file *df)
 {
 }
 #endif
diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c
index f4c9c27c7d74..74da44973594 100644
--- a/drivers/vfio/vfio_main.c
+++ b/drivers/vfio/vfio_main.c
@@ -435,7 +435,7 @@ static int vfio_device_first_open(struct vfio_device_file *df)
 	 * noiommu mode then just go ahead to open it.
 	 */
 	if (iommufd)
-		ret = vfio_iommufd_bind(device, iommufd);
+		ret = vfio_iommufd_bind(df);
 	else if (vfio_device_group_uses_container(df))
 		ret = vfio_device_group_use_iommu(device);
 	if (ret)
@@ -450,7 +450,7 @@ static int vfio_device_first_open(struct vfio_device_file *df)
 
 err_unuse_iommu:
 	if (iommufd)
-		vfio_iommufd_unbind(device);
+		vfio_iommufd_unbind(df);
 	else if (vfio_device_group_uses_container(df))
 		vfio_device_group_unuse_iommu(device);
 err_module_put:
@@ -468,7 +468,7 @@ static void vfio_device_last_close(struct vfio_device_file *df)
 	if (device->ops->close_device)
 		device->ops->close_device(device);
 	if (iommufd)
-		vfio_iommufd_unbind(device);
+		vfio_iommufd_unbind(df);
 	else if (vfio_device_group_uses_container(df))
 		vfio_device_group_unuse_iommu(device);
 	module_put(device->dev->driver->owner);
-- 
2.34.1