[PATCH v7 02/28] iommufd/viommu: Explicitly define vdev->virt_id

[Nicolin Chen <nicolinc@nvidia.com>]

The "id" is too genernal to get its meaning easily. Rename it explicitly to
"virt_id" and update the kdocs for readability. No functional changes.

Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
---
 drivers/iommu/iommufd/iommufd_private.h | 7 ++++++-
 drivers/iommu/iommufd/driver.c          | 2 +-
 drivers/iommu/iommufd/viommu.c          | 4 ++--
 3 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h
index 4f5e8cd99c96..09f895638f68 100644
--- a/drivers/iommu/iommufd/iommufd_private.h
+++ b/drivers/iommu/iommufd/iommufd_private.h
@@ -634,7 +634,12 @@ struct iommufd_vdevice {
 	struct iommufd_object obj;
 	struct iommufd_viommu *viommu;
 	struct device *dev;
-	u64 id; /* per-vIOMMU virtual ID */
+
+	/*
+	 * Virtual device ID per vIOMMU, e.g. vSID of ARM SMMUv3, vDeviceID of
+	 * AMD IOMMU, and vRID of a nested Intel VT-d to a Context Table
+	 */
+	u64 virt_id;
 };
 
 #ifdef CONFIG_IOMMUFD_TEST
diff --git a/drivers/iommu/iommufd/driver.c b/drivers/iommu/iommufd/driver.c
index 2fee399a148e..887719016804 100644
--- a/drivers/iommu/iommufd/driver.c
+++ b/drivers/iommu/iommufd/driver.c
@@ -30,7 +30,7 @@ int iommufd_viommu_get_vdev_id(struct iommufd_viommu *viommu,
 	xa_lock(&viommu->vdevs);
 	xa_for_each(&viommu->vdevs, index, vdev) {
 		if (vdev->dev == dev) {
-			*vdev_id = vdev->id;
+			*vdev_id = vdev->virt_id;
 			rc = 0;
 			break;
 		}
diff --git a/drivers/iommu/iommufd/viommu.c b/drivers/iommu/iommufd/viommu.c
index 25ac08fbb52a..bc8796e6684e 100644
--- a/drivers/iommu/iommufd/viommu.c
+++ b/drivers/iommu/iommufd/viommu.c
@@ -111,7 +111,7 @@ void iommufd_vdevice_destroy(struct iommufd_object *obj)
 	struct iommufd_viommu *viommu = vdev->viommu;
 
 	/* xa_cmpxchg is okay to fail if alloc failed xa_cmpxchg previously */
-	xa_cmpxchg(&viommu->vdevs, vdev->id, vdev, NULL, GFP_KERNEL);
+	xa_cmpxchg(&viommu->vdevs, vdev->virt_id, vdev, NULL, GFP_KERNEL);
 	refcount_dec(&viommu->obj.users);
 	put_device(vdev->dev);
 }
@@ -150,7 +150,7 @@ int iommufd_vdevice_alloc_ioctl(struct iommufd_ucmd *ucmd)
 		goto out_put_idev;
 	}
 
-	vdev->id = virt_id;
+	vdev->virt_id = virt_id;
 	vdev->dev = idev->dev;
 	get_device(idev->dev);
 	vdev->viommu = viommu;
-- 
2.43.0