[Intel-gfx] [PATCH v15 19/26] vfio: Test kvm pointer in _vfio_device_get_kvm_safe()

[Yi Liu <yi.l.liu@intel.com>]

This saves some lines when adding the kvm get logic for the vfio_device
cdev path.

This also renames _vfio_device_get_kvm_safe() to be vfio_device_get_kvm_safe().

Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
---
 drivers/vfio/group.c     | 7 +------
 drivers/vfio/vfio.h      | 6 +++---
 drivers/vfio/vfio_main.c | 5 ++++-
 3 files changed, 8 insertions(+), 10 deletions(-)

diff --git a/drivers/vfio/group.c b/drivers/vfio/group.c
index 41a09a2df690..5c17ad812313 100644
--- a/drivers/vfio/group.c
+++ b/drivers/vfio/group.c
@@ -160,12 +160,7 @@ static int vfio_group_ioctl_set_container(struct vfio_group *group,
 static void vfio_device_group_get_kvm_safe(struct vfio_device *device)
 {
 	spin_lock(&device->group->kvm_ref_lock);
-	if (!device->group->kvm)
-		goto unlock;
-
-	_vfio_device_get_kvm_safe(device, device->group->kvm);
-
-unlock:
+	vfio_device_get_kvm_safe(device, device->group->kvm);
 	spin_unlock(&device->group->kvm_ref_lock);
 }
 
diff --git a/drivers/vfio/vfio.h b/drivers/vfio/vfio.h
index fb8f2fac3d23..c2aa65382592 100644
--- a/drivers/vfio/vfio.h
+++ b/drivers/vfio/vfio.h
@@ -340,11 +340,11 @@ enum { vfio_noiommu = false };
 #endif
 
 #ifdef CONFIG_HAVE_KVM
-void _vfio_device_get_kvm_safe(struct vfio_device *device, struct kvm *kvm);
+void vfio_device_get_kvm_safe(struct vfio_device *device, struct kvm *kvm);
 void vfio_device_put_kvm(struct vfio_device *device);
 #else
-static inline void _vfio_device_get_kvm_safe(struct vfio_device *device,
-					     struct kvm *kvm)
+static inline void vfio_device_get_kvm_safe(struct vfio_device *device,
+					    struct kvm *kvm)
 {
 }
 
diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c
index 8a9ebcc6980b..5f7c3151d8c0 100644
--- a/drivers/vfio/vfio_main.c
+++ b/drivers/vfio/vfio_main.c
@@ -373,7 +373,7 @@ void vfio_unregister_group_dev(struct vfio_device *device)
 EXPORT_SYMBOL_GPL(vfio_unregister_group_dev);
 
 #ifdef CONFIG_HAVE_KVM
-void _vfio_device_get_kvm_safe(struct vfio_device *device, struct kvm *kvm)
+void vfio_device_get_kvm_safe(struct vfio_device *device, struct kvm *kvm)
 {
 	void (*pfn)(struct kvm *kvm);
 	bool (*fn)(struct kvm *kvm);
@@ -381,6 +381,9 @@ void _vfio_device_get_kvm_safe(struct vfio_device *device, struct kvm *kvm)
 
 	lockdep_assert_held(&device->dev_set->lock);
 
+	if (!kvm)
+		return;
+
 	pfn = symbol_get(kvm_put_kvm);
 	if (WARN_ON(!pfn))
 		return;
-- 
2.34.1