[RFC PATCH 12/30] iommufd/device: Associate a kvm pointer to iommufd_device

[Xu Yilun <yilun.xu@linux.intel.com>]

From: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>

Add a struct kvm * to iommufd_device_bind() fn and associate it
with idev if bind is successful.

Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>

---
This patch and next Shameer's patch are part of the series:

  https://lore.kernel.org/all/20250319173202.78988-3-shameerali.kolothum.thodi@huawei.com/
---
 drivers/iommu/iommufd/device.c          | 5 ++++-
 drivers/iommu/iommufd/iommufd_private.h | 2 ++
 drivers/vfio/iommufd.c                  | 2 +-
 include/linux/iommufd.h                 | 4 +++-
 4 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c
index 2111bad72c72..37ef6bec2009 100644
--- a/drivers/iommu/iommufd/device.c
+++ b/drivers/iommu/iommufd/device.c
@@ -152,6 +152,7 @@ void iommufd_device_destroy(struct iommufd_object *obj)
  * iommufd_device_bind - Bind a physical device to an iommu fd
  * @ictx: iommufd file descriptor
  * @dev: Pointer to a physical device struct
+ * @kvm: Pointer to struct kvm if device belongs to a KVM VM
  * @id: Output ID number to return to userspace for this device
  *
  * A successful bind establishes an ownership over the device and returns
@@ -165,7 +166,8 @@ void iommufd_device_destroy(struct iommufd_object *obj)
  * The caller must undo this with iommufd_device_unbind()
  */
 struct iommufd_device *iommufd_device_bind(struct iommufd_ctx *ictx,
-					   struct device *dev, u32 *id)
+					   struct device *dev, struct kvm *kvm,
+					   u32 *id)
 {
 	struct iommufd_device *idev;
 	struct iommufd_group *igroup;
@@ -215,6 +217,7 @@ struct iommufd_device *iommufd_device_bind(struct iommufd_ctx *ictx,
 	if (!iommufd_selftest_is_mock_dev(dev))
 		iommufd_ctx_get(ictx);
 	idev->dev = dev;
+	idev->kvm = kvm;
 	idev->enforce_cache_coherency =
 		device_iommu_capable(dev, IOMMU_CAP_ENFORCE_CACHE_COHERENCY);
 	/* The calling driver is a user until iommufd_device_unbind() */
diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h
index 80e8c76d25f2..297e4e2a12d1 100644
--- a/drivers/iommu/iommufd/iommufd_private.h
+++ b/drivers/iommu/iommufd/iommufd_private.h
@@ -424,6 +424,8 @@ struct iommufd_device {
 	struct list_head group_item;
 	/* always the physical device */
 	struct device *dev;
+	/* ..and kvm if available */
+	struct kvm *kvm;
 	bool enforce_cache_coherency;
 	/* protect iopf_enabled counter */
 	struct mutex iopf_lock;
diff --git a/drivers/vfio/iommufd.c b/drivers/vfio/iommufd.c
index c8c3a2d53f86..3441d24538a8 100644
--- a/drivers/vfio/iommufd.c
+++ b/drivers/vfio/iommufd.c
@@ -115,7 +115,7 @@ int vfio_iommufd_physical_bind(struct vfio_device *vdev,
 {
 	struct iommufd_device *idev;
 
-	idev = iommufd_device_bind(ictx, vdev->dev, out_device_id);
+	idev = iommufd_device_bind(ictx, vdev->dev, vdev->kvm, out_device_id);
 	if (IS_ERR(idev))
 		return PTR_ERR(idev);
 	vdev->iommufd_device = idev;
diff --git a/include/linux/iommufd.h b/include/linux/iommufd.h
index 34b6e6ca4bfa..2b2d6095309c 100644
--- a/include/linux/iommufd.h
+++ b/include/linux/iommufd.h
@@ -24,6 +24,7 @@ struct iommufd_ctx;
 struct iommufd_device;
 struct iommufd_viommu_ops;
 struct page;
+struct kvm;
 
 enum iommufd_object_type {
 	IOMMUFD_OBJ_NONE,
@@ -52,7 +53,8 @@ struct iommufd_object {
 };
 
 struct iommufd_device *iommufd_device_bind(struct iommufd_ctx *ictx,
-					   struct device *dev, u32 *id);
+					   struct device *dev, struct kvm *kvm,
+					   u32 *id);
 void iommufd_device_unbind(struct iommufd_device *idev);
 
 int iommufd_device_attach(struct iommufd_device *idev, ioasid_t pasid,
-- 
2.25.1