Commit 38a68934 authored by Jason Gunthorpe's avatar Jason Gunthorpe Committed by Alex Williamson
Browse files

vfio: Move vfio_iommu_group_get() to vfio_register_group_dev() 



We don't need to hold a reference to the group in the driver as well as
obtain a reference to the same group as the first thing
vfio_register_group_dev() does.

Since the drivers never use the group move this all into the core code.

Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20210924155705.4258-2-hch@lst.de


Signed-off-by: default avatarAlex Williamson <alex.williamson@redhat.com>
parent 5816b3e6

drivers/vfio/fsl-mc/vfio_fsl_mc.c

+2 −15
Original line number Diff line number Diff line
@@ -505,22 +505,13 @@ static void vfio_fsl_uninit_device(struct vfio_fsl_mc_device *vdev) 


static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)

{

	struct iommu_group *group;

	struct vfio_fsl_mc_device *vdev;

	struct device *dev = &mc_dev->dev;

	int ret;



	group = vfio_iommu_group_get(dev);

	if (!group) {

		dev_err(dev, "VFIO_FSL_MC: No IOMMU group\n");

		return -EINVAL;

	}



	vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);

	if (!vdev) {

		ret = -ENOMEM;

		goto out_group_put;

	}

	if (!vdev)

		return -ENOMEM;



	vfio_init_group_dev(&vdev->vdev, dev, &vfio_fsl_mc_ops);

	vdev->mc_dev = mc_dev;
@@ -556,8 +547,6 @@ static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev) 
out_uninit:

	vfio_uninit_group_dev(&vdev->vdev);

	kfree(vdev);

out_group_put:

	vfio_iommu_group_put(group, dev);

	return ret;

}
@@ -574,8 +563,6 @@ static int vfio_fsl_mc_remove(struct fsl_mc_device *mc_dev) 


	vfio_uninit_group_dev(&vdev->vdev);

	kfree(vdev);

	vfio_iommu_group_put(mc_dev->dev.iommu_group, dev);



	return 0;

}

drivers/vfio/pci/vfio_pci_core.c

+2 −11
Original line number Diff line number Diff line
@@ -1806,7 +1806,6 @@ EXPORT_SYMBOL_GPL(vfio_pci_core_uninit_device); 
int vfio_pci_core_register_device(struct vfio_pci_core_device *vdev)

{

	struct pci_dev *pdev = vdev->pdev;

	struct iommu_group *group;

	int ret;



	if (pdev->hdr_type != PCI_HEADER_TYPE_NORMAL)
@@ -1825,10 +1824,6 @@ int vfio_pci_core_register_device(struct vfio_pci_core_device *vdev) 
		return -EBUSY;

	}



	group = vfio_iommu_group_get(&pdev->dev);

	if (!group)

		return -EINVAL;



	if (pci_is_root_bus(pdev->bus)) {

		ret = vfio_assign_device_set(&vdev->vdev, vdev);

	} else if (!pci_probe_reset_slot(pdev->slot)) {
@@ -1842,10 +1837,10 @@ int vfio_pci_core_register_device(struct vfio_pci_core_device *vdev) 
	}



	if (ret)

		goto out_group_put;

		return ret;

	ret = vfio_pci_vf_init(vdev);

	if (ret)

		goto out_group_put;

		return ret;

	ret = vfio_pci_vga_init(vdev);

	if (ret)

		goto out_vf;
@@ -1876,8 +1871,6 @@ int vfio_pci_core_register_device(struct vfio_pci_core_device *vdev) 
		vfio_pci_set_power_state(vdev, PCI_D0);

out_vf:

	vfio_pci_vf_uninit(vdev);

out_group_put:

	vfio_iommu_group_put(group, &pdev->dev);

	return ret;

}

EXPORT_SYMBOL_GPL(vfio_pci_core_register_device);
@@ -1893,8 +1886,6 @@ void vfio_pci_core_unregister_device(struct vfio_pci_core_device *vdev) 
	vfio_pci_vf_uninit(vdev);

	vfio_pci_vga_uninit(vdev);



	vfio_iommu_group_put(pdev->dev.iommu_group, &pdev->dev);



	if (!disable_idle_d3)

		vfio_pci_set_power_state(vdev, PCI_D0);

}

drivers/vfio/platform/vfio_platform_common.c

+1 −12
Original line number Diff line number Diff line
@@ -642,7 +642,6 @@ static int vfio_platform_of_probe(struct vfio_platform_device *vdev, 
int vfio_platform_probe_common(struct vfio_platform_device *vdev,

			       struct device *dev)

{

	struct iommu_group *group;

	int ret;



	vfio_init_group_dev(&vdev->vdev, dev, &vfio_platform_ops);
@@ -663,24 +662,15 @@ int vfio_platform_probe_common(struct vfio_platform_device *vdev, 
		goto out_uninit;

	}



	group = vfio_iommu_group_get(dev);

	if (!group) {

		dev_err(dev, "No IOMMU group for device %s\n", vdev->name);

		ret = -EINVAL;

		goto put_reset;

	}



	ret = vfio_register_group_dev(&vdev->vdev);

	if (ret)

		goto put_iommu;

		goto put_reset;



	mutex_init(&vdev->igate);



	pm_runtime_enable(dev);

	return 0;



put_iommu:

	vfio_iommu_group_put(group, dev);

put_reset:

	vfio_platform_put_reset(vdev);

out_uninit:
@@ -696,7 +686,6 @@ void vfio_platform_remove_common(struct vfio_platform_device *vdev) 
	pm_runtime_disable(vdev->device);

	vfio_platform_put_reset(vdev);

	vfio_uninit_group_dev(&vdev->vdev);

	vfio_iommu_group_put(vdev->vdev.dev->iommu_group, vdev->vdev.dev);

}

EXPORT_SYMBOL_GPL(vfio_platform_remove_common);

drivers/vfio/vfio.c

+14 −22
Original line number Diff line number Diff line
@@ -169,15 +169,7 @@ static void vfio_release_device_set(struct vfio_device *device) 
	xa_unlock(&vfio_device_set_xa);

}



/*

 * vfio_iommu_group_{get,put} are only intended for VFIO bus driver probe

 * and remove functions, any use cases other than acquiring the first

 * reference for the purpose of calling vfio_register_group_dev() or removing

 * that symmetric reference after vfio_unregister_group_dev() should use the raw

 * iommu_group_{get,put} functions.  In particular, vfio_iommu_group_put()

 * removes the device from the dummy group and cannot be nested.

 */

struct iommu_group *vfio_iommu_group_get(struct device *dev)

static struct iommu_group *vfio_iommu_group_get(struct device *dev)

{

	struct iommu_group *group;

	int __maybe_unused ret;
@@ -220,18 +212,6 @@ struct iommu_group *vfio_iommu_group_get(struct device *dev) 


	return group;

}

EXPORT_SYMBOL_GPL(vfio_iommu_group_get);



void vfio_iommu_group_put(struct iommu_group *group, struct device *dev)

{

#ifdef CONFIG_VFIO_NOIOMMU

	if (iommu_group_get_iommudata(group) == &noiommu)

		iommu_group_remove_device(dev);

#endif



	iommu_group_put(group);

}

EXPORT_SYMBOL_GPL(vfio_iommu_group_put);



#ifdef CONFIG_VFIO_NOIOMMU

static void *vfio_noiommu_open(unsigned long arg)
@@ -841,7 +821,7 @@ int vfio_register_group_dev(struct vfio_device *device) 
	if (!device->dev_set)

		vfio_assign_device_set(device, device);



	iommu_group = iommu_group_get(device->dev);

	iommu_group = vfio_iommu_group_get(device->dev);

	if (!iommu_group)

		return -EINVAL;
@@ -849,6 +829,10 @@ int vfio_register_group_dev(struct vfio_device *device) 
	if (!group) {

		group = vfio_create_group(iommu_group);

		if (IS_ERR(group)) {

#ifdef CONFIG_VFIO_NOIOMMU

			if (iommu_group_get_iommudata(iommu_group) == &noiommu)

				iommu_group_remove_device(device->dev);

#endif

			iommu_group_put(iommu_group);

			return PTR_ERR(group);

		}
@@ -865,6 +849,10 @@ int vfio_register_group_dev(struct vfio_device *device) 
		dev_WARN(device->dev, "Device already exists on group %d\n",

			 iommu_group_id(iommu_group));

		vfio_device_put(existing_device);

#ifdef CONFIG_VFIO_NOIOMMU

		if (iommu_group_get_iommudata(iommu_group) == &noiommu)

			iommu_group_remove_device(device->dev);

#endif

		vfio_group_put(group);

		return -EBUSY;

	}
@@ -1010,6 +998,10 @@ void vfio_unregister_group_dev(struct vfio_device *device) 
	if (list_empty(&group->device_list))

		wait_event(group->container_q, !group->container);



#ifdef CONFIG_VFIO_NOIOMMU

	if (iommu_group_get_iommudata(group->iommu_group) == &noiommu)

		iommu_group_remove_device(device->dev);

#endif

	/* Matches the get in vfio_register_group_dev() */

	vfio_group_put(group);

}

include/linux/vfio.h

+0 −3
Original line number Diff line number Diff line
@@ -71,9 +71,6 @@ struct vfio_device_ops { 
	int	(*match)(struct vfio_device *vdev, char *buf);

};



extern struct iommu_group *vfio_iommu_group_get(struct device *dev);

extern void vfio_iommu_group_put(struct iommu_group *group, struct device *dev);



void vfio_init_group_dev(struct vfio_device *device, struct device *dev,

			 const struct vfio_device_ops *ops);

void vfio_uninit_group_dev(struct vfio_device *device);