Commit a4d1f91d authored by Jason Gunthorpe's avatar Jason Gunthorpe
Browse files

vfio-iommufd: Support iommufd for physical VFIO devices 

This creates the iommufd_device for the physical VFIO drivers. These are
all the drivers that are calling vfio_register_group_dev() and expect the
type1 code to setup a real iommu_domain against their parent struct
device.

The design gives the driver a choice in how it gets connected to iommufd
by providing bind_iommufd/unbind_iommufd/attach_ioas callbacks to
implement as required. The core code provides three default callbacks for
physical mode using a real iommu_domain. This is suitable for drivers
using vfio_register_group_dev()

Link: https://lore.kernel.org/r/6-v4-42cd2eb0e3eb+335a-vfio_iommufd_jgg@nvidia.com


Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Reviewed-by: default avatarAlex Williamson <alex.williamson@redhat.com>
Tested-by: default avatarAlex Williamson <alex.williamson@redhat.com>
Tested-by: default avatarNicolin Chen <nicolinc@nvidia.com>
Tested-by: default avatarYi Liu <yi.l.liu@intel.com>
Tested-by: default avatarLixiao Yang <lixiao.yang@intel.com>
Tested-by: default avatarMatthew Rosato <mjrosato@linux.ibm.com>
Tested-by: default avatarYu He <yu.he@intel.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
parent 2a3dab19

drivers/vfio/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -6,6 +6,7 @@ obj-$(CONFIG_VFIO) += vfio.o 
vfio-y += vfio_main.o \

	  iova_bitmap.o \

	  container.o

vfio-$(CONFIG_IOMMUFD) += iommufd.o



obj-$(CONFIG_VFIO_VIRQFD) += vfio_virqfd.o

obj-$(CONFIG_VFIO_IOMMU_TYPE1) += vfio_iommu_type1.o

drivers/vfio/fsl-mc/vfio_fsl_mc.c

+3 −0
Original line number Diff line number Diff line
@@ -592,6 +592,9 @@ static const struct vfio_device_ops vfio_fsl_mc_ops = { 
	.read		= vfio_fsl_mc_read,

	.write		= vfio_fsl_mc_write,

	.mmap		= vfio_fsl_mc_mmap,

	.bind_iommufd	= vfio_iommufd_physical_bind,

	.unbind_iommufd	= vfio_iommufd_physical_unbind,

	.attach_ioas	= vfio_iommufd_physical_attach_ioas,

};



static struct fsl_mc_driver vfio_fsl_mc_driver = {

drivers/vfio/iommufd.c

0 → 100644
+100 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-only

/*

 * Copyright (c) 2021-2022, NVIDIA CORPORATION & AFFILIATES

 */

#include <linux/vfio.h>

#include <linux/iommufd.h>



#include "vfio.h"



MODULE_IMPORT_NS(IOMMUFD);

MODULE_IMPORT_NS(IOMMUFD_VFIO);



int vfio_iommufd_bind(struct vfio_device *vdev, struct iommufd_ctx *ictx)

{

	u32 ioas_id;

	u32 device_id;

	int ret;



	lockdep_assert_held(&vdev->dev_set->lock);



	/*

	 * If the driver doesn't provide this op then it means the device does

	 * not do DMA at all. So nothing to do.

	 */

	if (!vdev->ops->bind_iommufd)

		return 0;



	ret = vdev->ops->bind_iommufd(vdev, ictx, &device_id);

	if (ret)

		return ret;



	ret = iommufd_vfio_compat_ioas_id(ictx, &ioas_id);

	if (ret)

		goto err_unbind;

	ret = vdev->ops->attach_ioas(vdev, &ioas_id);

	if (ret)

		goto err_unbind;



	/*

	 * The legacy path has no way to return the device id or the selected

	 * pt_id

	 */

	return 0;



err_unbind:

	if (vdev->ops->unbind_iommufd)

		vdev->ops->unbind_iommufd(vdev);

	return ret;

}



void vfio_iommufd_unbind(struct vfio_device *vdev)

{

	lockdep_assert_held(&vdev->dev_set->lock);



	if (vdev->ops->unbind_iommufd)

		vdev->ops->unbind_iommufd(vdev);

}



/*

 * The physical standard ops mean that the iommufd_device is bound to the

 * physical device vdev->dev that was provided to vfio_init_group_dev(). Drivers

 * using this ops set should call vfio_register_group_dev()

 */

int vfio_iommufd_physical_bind(struct vfio_device *vdev,

			       struct iommufd_ctx *ictx, u32 *out_device_id)

{

	struct iommufd_device *idev;



	idev = iommufd_device_bind(ictx, vdev->dev, out_device_id);

	if (IS_ERR(idev))

		return PTR_ERR(idev);

	vdev->iommufd_device = idev;

	return 0;

}

EXPORT_SYMBOL_GPL(vfio_iommufd_physical_bind);



void vfio_iommufd_physical_unbind(struct vfio_device *vdev)

{

	lockdep_assert_held(&vdev->dev_set->lock);



	if (vdev->iommufd_attached) {

		iommufd_device_detach(vdev->iommufd_device);

		vdev->iommufd_attached = false;

	}

	iommufd_device_unbind(vdev->iommufd_device);

	vdev->iommufd_device = NULL;

}

EXPORT_SYMBOL_GPL(vfio_iommufd_physical_unbind);



int vfio_iommufd_physical_attach_ioas(struct vfio_device *vdev, u32 *pt_id)

{

	int rc;



	rc = iommufd_device_attach(vdev->iommufd_device, pt_id);

	if (rc)

		return rc;

	vdev->iommufd_attached = true;

	return 0;

}

EXPORT_SYMBOL_GPL(vfio_iommufd_physical_attach_ioas);

drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c

+6 −0
Original line number Diff line number Diff line
@@ -1246,6 +1246,9 @@ static const struct vfio_device_ops hisi_acc_vfio_pci_migrn_ops = { 
	.mmap = hisi_acc_vfio_pci_mmap,

	.request = vfio_pci_core_request,

	.match = vfio_pci_core_match,

	.bind_iommufd = vfio_iommufd_physical_bind,

	.unbind_iommufd = vfio_iommufd_physical_unbind,

	.attach_ioas = vfio_iommufd_physical_attach_ioas,

};



static const struct vfio_device_ops hisi_acc_vfio_pci_ops = {
@@ -1261,6 +1264,9 @@ static const struct vfio_device_ops hisi_acc_vfio_pci_ops = { 
	.mmap = vfio_pci_core_mmap,

	.request = vfio_pci_core_request,

	.match = vfio_pci_core_match,

	.bind_iommufd = vfio_iommufd_physical_bind,

	.unbind_iommufd = vfio_iommufd_physical_unbind,

	.attach_ioas = vfio_iommufd_physical_attach_ioas,

};



static int hisi_acc_vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)

drivers/vfio/pci/mlx5/main.c

+3 −0
Original line number Diff line number Diff line
@@ -623,6 +623,9 @@ static const struct vfio_device_ops mlx5vf_pci_ops = { 
	.mmap = vfio_pci_core_mmap,

	.request = vfio_pci_core_request,

	.match = vfio_pci_core_match,

	.bind_iommufd = vfio_iommufd_physical_bind,

	.unbind_iommufd = vfio_iommufd_physical_unbind,

	.attach_ioas = vfio_iommufd_physical_attach_ioas,

};



static int mlx5vf_pci_probe(struct pci_dev *pdev,