vfio/mbochs: Use the new device life cycle helpers

and manage avail_mbytes inside @init/@Release.

Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20220921104401.38898-8-kevin.tian@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

samples/vfio-mdev/mbochs.c

@@ -505,13 +505,14 @@ static int mbochs_reset(struct mdev_state *mdev_state)
 	return 0;
 }
 
-static int mbochs_probe(struct mdev_device *mdev)
+static int mbochs_init_dev(struct vfio_device *vdev)
 {
-	int avail_mbytes = atomic_read(&mbochs_avail_mbytes);
+	struct mdev_state *mdev_state =
+		container_of(vdev, struct mdev_state, vdev);
+	struct mdev_device *mdev = to_mdev_device(vdev->dev);
 	const struct mbochs_type *type =
 		&mbochs_types[mdev_get_type_group_id(mdev)];
-	struct device *dev = mdev_dev(mdev);
-	struct mdev_state *mdev_state;
+	int avail_mbytes = atomic_read(&mbochs_avail_mbytes);
 	int ret = -ENOMEM;
 
 	do {
@@ -520,25 +521,17 @@ static int mbochs_probe(struct mdev_device *mdev)
 	} while (!atomic_try_cmpxchg(&mbochs_avail_mbytes, &avail_mbytes,
 				     avail_mbytes - type->mbytes));
 
-	mdev_state = kzalloc(sizeof(struct mdev_state), GFP_KERNEL);
-	if (mdev_state == NULL)
-		goto err_avail;
-	vfio_init_group_dev(&mdev_state->vdev, &mdev->dev, &mbochs_dev_ops);
-
 	mdev_state->vconfig = kzalloc(MBOCHS_CONFIG_SPACE_SIZE, GFP_KERNEL);
-	if (mdev_state->vconfig == NULL)
-		goto err_mem;
+	if (!mdev_state->vconfig)
+		goto err_avail;
 
 	mdev_state->memsize = type->mbytes * 1024 * 1024;
 	mdev_state->pagecount = mdev_state->memsize >> PAGE_SHIFT;
 	mdev_state->pages = kcalloc(mdev_state->pagecount,
 				    sizeof(struct page *),
 				    GFP_KERNEL);
 	if (!mdev_state->pages)
-		goto err_mem;
-
-	dev_info(dev, "%s: %s, %d MB, %ld pages\n", __func__,
-		 type->name, type->mbytes, mdev_state->pagecount);
+		goto err_vconfig;
 
 	mutex_init(&mdev_state->ops_lock);
 	mdev_state->mdev = mdev;
@@ -553,31 +546,55 @@ static int mbochs_probe(struct mdev_device *mdev)
 	mbochs_create_config_space(mdev_state);
 	mbochs_reset(mdev_state);
 
+	dev_info(vdev->dev, "%s: %s, %d MB, %ld pages\n", __func__,
+		 type->name, type->mbytes, mdev_state->pagecount);
+	return 0;
+
+err_vconfig:
+	kfree(mdev_state->vconfig);
+err_avail:
+	atomic_add(type->mbytes, &mbochs_avail_mbytes);
+	return ret;
+}
+
+static int mbochs_probe(struct mdev_device *mdev)
+{
+	struct mdev_state *mdev_state;
+	int ret = -ENOMEM;
+
+	mdev_state = vfio_alloc_device(mdev_state, vdev, &mdev->dev,
+				       &mbochs_dev_ops);
+	if (IS_ERR(mdev_state))
+		return PTR_ERR(mdev_state);
+
 	ret = vfio_register_emulated_iommu_dev(&mdev_state->vdev);
 	if (ret)
-		goto err_mem;
+		goto err_put_vdev;
 	dev_set_drvdata(&mdev->dev, mdev_state);
 	return 0;
-err_mem:
-	vfio_uninit_group_dev(&mdev_state->vdev);
+
+err_put_vdev:
+	vfio_put_device(&mdev_state->vdev);
+	return ret;
+}
+
+static void mbochs_release_dev(struct vfio_device *vdev)
+{
+	struct mdev_state *mdev_state =
+		container_of(vdev, struct mdev_state, vdev);
+
+	atomic_add(mdev_state->type->mbytes, &mbochs_avail_mbytes);
 	kfree(mdev_state->pages);
 	kfree(mdev_state->vconfig);
-	kfree(mdev_state);
-err_avail:
-	atomic_add(type->mbytes, &mbochs_avail_mbytes);
-	return ret;
+	vfio_free_device(vdev);
 }
 
 static void mbochs_remove(struct mdev_device *mdev)
 {
 	struct mdev_state *mdev_state = dev_get_drvdata(&mdev->dev);
 
 	vfio_unregister_group_dev(&mdev_state->vdev);
-	vfio_uninit_group_dev(&mdev_state->vdev);
-	atomic_add(mdev_state->type->mbytes, &mbochs_avail_mbytes);
-	kfree(mdev_state->pages);
-	kfree(mdev_state->vconfig);
-	kfree(mdev_state);
+	vfio_put_device(&mdev_state->vdev);
 }
 
 static ssize_t mbochs_read(struct vfio_device *vdev, char __user *buf,
@@ -1397,6 +1414,8 @@ static struct attribute_group *mdev_type_groups[] = {
 
 static const struct vfio_device_ops mbochs_dev_ops = {
 	.close_device = mbochs_close_device,
+	.init = mbochs_init_dev,
+	.release = mbochs_release_dev,
 	.read = mbochs_read,
 	.write = mbochs_write,
 	.ioctl = mbochs_ioctl,