[RFC 2/7] iommufd: Introduce iommufd_alloc_device()

From: Yi Liu
Date: Mon Oct 09 2023 - 04:52:35 EST


From: Kevin Tian <kevin.tian@xxxxxxxxx>

This abstracts the common logic used in the iommufd_device_bind() and the
later iommufd_device_bind_pasid() to be helper.

Signed-off-by: Kevin Tian <kevin.tian@xxxxxxxxx>
Signed-off-by: Yi Liu <yi.l.liu@xxxxxxxxx>
---
drivers/iommu/iommufd/device.c | 34 +++++++++++++++++++++++-----------
1 file changed, 23 insertions(+), 11 deletions(-)

diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c
index ca3919fecc89..9dd76d92b7f6 100644
--- a/drivers/iommu/iommufd/device.c
+++ b/drivers/iommu/iommufd/device.c
@@ -164,6 +164,27 @@ static int iommufd_allow_unsafe_interrupts(struct device *dev)
return 0;
}

+static struct iommufd_device *iommufd_alloc_device(struct iommufd_ctx *ictx,
+ struct device *dev)
+{
+ struct iommufd_device *idev;
+
+ idev = iommufd_object_alloc(ictx, idev, IOMMUFD_OBJ_DEVICE);
+ if (IS_ERR(idev))
+ return idev;
+ idev->ictx = ictx;
+ if (!iommufd_selftest_is_mock_dev(dev))
+ iommufd_ctx_get(ictx);
+ idev->dev = dev;
+ idev->enforce_cache_coherency =
+ device_iommu_capable(dev, IOMMU_CAP_ENFORCE_CACHE_COHERENCY);
+ xa_init(&idev->pasid_hwpts);
+
+ /* The calling driver is a user until iommufd_device_unbind() */
+ refcount_inc(&idev->obj.users);
+ return idev;
+}
+
/**
* iommufd_device_bind - Bind a physical device to an iommu fd
* @ictx: iommufd file descriptor
@@ -209,24 +230,15 @@ struct iommufd_device *iommufd_device_bind(struct iommufd_ctx *ictx,
if (rc)
goto out_group_put;

- idev = iommufd_object_alloc(ictx, idev, IOMMUFD_OBJ_DEVICE);
+ idev = iommufd_alloc_device(ictx, dev);
if (IS_ERR(idev)) {
rc = PTR_ERR(idev);
goto out_release_owner;
}
- idev->ictx = ictx;
- if (!iommufd_selftest_is_mock_dev(dev))
- iommufd_ctx_get(ictx);
- idev->dev = dev;
- idev->enforce_cache_coherency =
- device_iommu_capable(dev, IOMMU_CAP_ENFORCE_CACHE_COHERENCY);
- /* The calling driver is a user until iommufd_device_unbind() */
- refcount_inc(&idev->obj.users);
+
/* igroup refcount moves into iommufd_device */
idev->igroup = igroup;

- xa_init(&idev->pasid_hwpts);
-
/*
* If the caller fails after this success it must call
* iommufd_unbind_device() which is safe since we hold this refcount.
--
2.34.1