[PATCH v3 09/16] iommufd/viommu: Add vdev_to_dev helper

[Nicolin Chen]

This avoids a bigger trouble of moving the struct iommufd_device to the
public header.

Signed-off-by: Nicolin Chen <nicolinc@xxxxxxxxxx>
---
 include/linux/iommufd.h            | 7 +++++++
 drivers/iommu/iommufd/viommu_api.c | 7 +++++++
 2 files changed, 14 insertions(+)

diff --git a/include/linux/iommufd.h b/include/linux/iommufd.h
index e58b3e43aa7b..18d9b95f1cbc 100644
--- a/include/linux/iommufd.h
+++ b/include/linux/iommufd.h
@@ -85,6 +85,7 @@ struct iommufd_vdevice {
 	struct iommufd_viommu *viommu;
 	u64 id; /* per-vIOMMU virtual ID */
 };
+struct device *vdev_to_dev(struct iommufd_vdevice *vdev);
 
 /**
  * struct iommufd_viommu_ops - vIOMMU specific operations
@@ -134,6 +135,7 @@ __iommufd_viommu_alloc(struct iommufd_ctx *ictx, size_t size,
 		       const struct iommufd_viommu_ops *ops);
 struct iommufd_vdevice *
 __iommufd_vdevice_alloc(struct iommufd_ctx *ictx, size_t size);
+struct device *vdev_to_dev(struct iommufd_vdevice *vdev);
 #else /* !CONFIG_IOMMUFD */
 static inline struct iommufd_ctx *iommufd_ctx_from_file(struct file *file)
 {
@@ -187,6 +189,11 @@ __iommufd_vdevice_alloc(struct iommufd_ctx *ictx, size_t size)
 {
 	return ERR_PTR(-EOPNOTSUPP);
 }
+
+static inline struct device *vdev_to_dev(struct iommufd_vdevice *vdev)
+{
+	return NULL;
+}
 #endif /* CONFIG_IOMMUFD */
 
 /*
diff --git a/drivers/iommu/iommufd/viommu_api.c b/drivers/iommu/iommufd/viommu_api.c
index 8419df3b658c..281e85be520d 100644
--- a/drivers/iommu/iommufd/viommu_api.c
+++ b/drivers/iommu/iommufd/viommu_api.c
@@ -69,3 +69,10 @@ __iommufd_vdevice_alloc(struct iommufd_ctx *ictx, size_t size)
 	return container_of(obj, struct iommufd_vdevice, obj);
 }
 EXPORT_SYMBOL_NS_GPL(__iommufd_vdevice_alloc, IOMMUFD);
+
+/* Caller should xa_lock(&viommu->vdevs) to protect the return value */
+struct device *vdev_to_dev(struct iommufd_vdevice *vdev)
+{
+	return vdev ? vdev->idev->dev : NULL;
+}
+EXPORT_SYMBOL_NS_GPL(vdev_to_dev, IOMMUFD);
-- 
2.43.0