[PATCH v1 07/10] vfio: Export vfio device get and put registration helpers

Leon Romanovsky
2025-08-04T13:01:23Z

From: Vivek Kasireddy <vivek.kasireddy@intel.com>

These helpers are useful for managing additional references taken
on the device from other associated VFIO modules.

Original-patch-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
---
drivers/vfio/vfio_main.c | 2 ++
include/linux/vfio.h | 2 ++
2 files changed, 4 insertions(+)

diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c
index 1fd261efc582d..620a3ee5d04db 100644
--- a/drivers/vfio/vfio_main.c
+++ b/drivers/vfio/vfio_main.c
@@ -171,11 +171,13 @@ void vfio_device_put_registration(struct vfio_device *device)
if (refcount_dec_and_test(&device->refcount))
complete(&device->comp);
}
+EXPORT_SYMBOL_GPL(vfio_device_put_registration);

bool vfio_device_try_get_registration(struct vfio_device *device)
{
return refcount_inc_not_zero(&device->refcount);
}
+EXPORT_SYMBOL_GPL(vfio_device_try_get_registration);

/*
* VFIO driver API
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index 707b00772ce1f..ba65bbdffd0b2 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -293,6 +293,8 @@ static inline void vfio_put_device(struct vfio_device *device)
int vfio_register_group_dev(struct vfio_device *device);
int vfio_register_emulated_iommu_dev(struct vfio_device *device);
void vfio_unregister_group_dev(struct vfio_device *device);
+bool vfio_device_try_get_registration(struct vfio_device *device);
+void vfio_device_put_registration(struct vfio_device *device);

int vfio_assign_device_set(struct vfio_device *device, void *set_id);
unsigned int vfio_device_set_open_count(struct vfio_device_set *dev_set);
--
2.50.1