vfio: Change vfio_group_set_kvm() to vfio_file_set_kvm()

Just change the argument from struct vfio_group to struct file *.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/6-v3-f7729924a7ea+25e33-vfio_kvm_no_group_jgg@nvidia.comSigned-off-by: Alex Williamson <alex.williamson@redhat.com>

drivers/vfio/vfio.c

@@ -1731,6 +1731,27 @@ bool vfio_file_enforced_coherent(struct file *file)
 }
 EXPORT_SYMBOL_GPL(vfio_file_enforced_coherent);
 
+/**
+ * vfio_file_set_kvm - Link a kvm with VFIO drivers
+ * @file: VFIO group file
+ * @kvm: KVM to link
+ *
+ * The kvm pointer will be forwarded to all the vfio_device's attached to the
+ * VFIO file via the VFIO_GROUP_NOTIFY_SET_KVM notifier.
+ */
+void vfio_file_set_kvm(struct file *file, struct kvm *kvm)
+{
+	struct vfio_group *group = file->private_data;
+
+	if (file->f_op != &vfio_group_fops)
+		return;
+
+	group->kvm = kvm;
+	blocking_notifier_call_chain(&group->notifier,
+				     VFIO_GROUP_NOTIFY_SET_KVM, kvm);
+}
+EXPORT_SYMBOL_GPL(vfio_file_set_kvm);
+
 /*
  * Sub-module support
  */
@@ -1999,14 +2020,6 @@ static int vfio_unregister_iommu_notifier(struct vfio_group *group,
 	return ret;
 }
 
-void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm)
-{
-	group->kvm = kvm;
-	blocking_notifier_call_chain(&group->notifier,
-				VFIO_GROUP_NOTIFY_SET_KVM, kvm);
-}
-EXPORT_SYMBOL_GPL(vfio_group_set_kvm);
-
 static int vfio_register_group_notifier(struct vfio_group *group,
 					unsigned long *events,
 					struct notifier_block *nb)

include/linux/vfio.h

@@ -15,6 +15,8 @@
 #include <linux/poll.h>
 #include <uapi/linux/vfio.h>
 
+struct kvm;
+
 /*
  * VFIO devices can be placed in a set, this allows all devices to share this
  * structure and the VFIO core will provide a lock that is held around
@@ -140,6 +142,7 @@ extern struct vfio_group *vfio_group_get_external_user(struct file *filep);
 extern void vfio_group_put_external_user(struct vfio_group *group);
 extern struct iommu_group *vfio_file_iommu_group(struct file *file);
 extern bool vfio_file_enforced_coherent(struct file *file);
+extern void vfio_file_set_kvm(struct file *file, struct kvm *kvm);
 
 #define VFIO_PIN_PAGES_MAX_ENTRIES	(PAGE_SIZE/sizeof(unsigned long))
 
@@ -170,8 +173,6 @@ extern int vfio_unregister_notifier(struct vfio_device *device,
 				    enum vfio_notify_type type,
 				    struct notifier_block *nb);
 
-struct kvm;
-extern void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm);
 
 /*
  * Sub-module helpers

virt/kvm/vfio.c

@@ -62,17 +62,17 @@ static void kvm_vfio_group_put_external_user(struct vfio_group *vfio_group)
 	symbol_put(vfio_group_put_external_user);
 }
 
-static void kvm_vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm)
+static void kvm_vfio_file_set_kvm(struct file *file, struct kvm *kvm)
 {
-	void (*fn)(struct vfio_group *, struct kvm *);
+	void (*fn)(struct file *file, struct kvm *kvm);
 
-	fn = symbol_get(vfio_group_set_kvm);
+	fn = symbol_get(vfio_file_set_kvm);
 	if (!fn)
 		return;
 
-	fn(group, kvm);
+	fn(file, kvm);
 
-	symbol_put(vfio_group_set_kvm);
+	symbol_put(vfio_file_set_kvm);
 }
 
 static bool kvm_vfio_file_enforced_coherent(struct file *file)
@@ -195,7 +195,7 @@ static int kvm_vfio_group_add(struct kvm_device *dev, unsigned int fd)
 
 	mutex_unlock(&kv->lock);
 
-	kvm_vfio_group_set_kvm(vfio_group, dev->kvm);
+	kvm_vfio_file_set_kvm(kvg->file, dev->kvm);
 	kvm_vfio_update_coherency(dev);
 
 	return 0;
@@ -231,7 +231,7 @@ static int kvm_vfio_group_del(struct kvm_device *dev, unsigned int fd)
 #ifdef CONFIG_SPAPR_TCE_IOMMU
 		kvm_spapr_tce_release_vfio_group(dev->kvm, kvg);
 #endif
-		kvm_vfio_group_set_kvm(kvg->vfio_group, NULL);
+		kvm_vfio_file_set_kvm(kvg->file, NULL);
 		kvm_vfio_group_put_external_user(kvg->vfio_group);
 		fput(kvg->file);
 		kfree(kvg);
@@ -360,7 +360,7 @@ static void kvm_vfio_destroy(struct kvm_device *dev)
 #ifdef CONFIG_SPAPR_TCE_IOMMU
 		kvm_spapr_tce_release_vfio_group(dev->kvm, kvg);
 #endif
-		kvm_vfio_group_set_kvm(kvg->vfio_group, NULL);
+		kvm_vfio_file_set_kvm(kvg->file, NULL);
 		kvm_vfio_group_put_external_user(kvg->vfio_group);
 		fput(kvg->file);
 		list_del(&kvg->node);