linux/drivers/vfio/iommufd.c
Yi Liu 7d12578c5d vfio: Check the presence for iommufd callbacks in __vfio_register_dev()
After making the no-DMA drivers (samples/vfio-mdev) providing iommufd
callbacks, __vfio_register_dev() should check the presence of the iommufd
callbacks if CONFIG_IOMMUFD is enabled.

Link: https://lore.kernel.org/r/20230327093351.44505-7-yi.l.liu@intel.com
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Tested-by: Terrence Xu <terrence.xu@intel.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2023-03-31 13:43:32 -03:00

175 lines
4.2 KiB
C

// 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 (vfio_device_is_noiommu(vdev)) {
if (!capable(CAP_SYS_RAWIO))
return -EPERM;
/*
* Require no compat ioas to be assigned to proceed. The basic
* statement is that the user cannot have done something that
* implies they expected translation to exist
*/
if (!iommufd_vfio_compat_ioas_get_id(ictx, &ioas_id))
return -EPERM;
return 0;
}
ret = vdev->ops->bind_iommufd(vdev, ictx, &device_id);
if (ret)
return ret;
ret = iommufd_vfio_compat_ioas_get_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 (vfio_device_is_noiommu(vdev))
return;
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);
/*
* The emulated standard ops mean that vfio_device is going to use the
* "mdev path" and will call vfio_pin_pages()/vfio_dma_rw(). Drivers using this
* ops set should call vfio_register_emulated_iommu_dev(). Drivers that do
* not call vfio_pin_pages()/vfio_dma_rw() have no need to provide dma_unmap.
*/
static void vfio_emulated_unmap(void *data, unsigned long iova,
unsigned long length)
{
struct vfio_device *vdev = data;
if (vdev->ops->dma_unmap)
vdev->ops->dma_unmap(vdev, iova, length);
}
static const struct iommufd_access_ops vfio_user_ops = {
.needs_pin_pages = 1,
.unmap = vfio_emulated_unmap,
};
int vfio_iommufd_emulated_bind(struct vfio_device *vdev,
struct iommufd_ctx *ictx, u32 *out_device_id)
{
struct iommufd_access *user;
lockdep_assert_held(&vdev->dev_set->lock);
user = iommufd_access_create(ictx, &vfio_user_ops, vdev, out_device_id);
if (IS_ERR(user))
return PTR_ERR(user);
vdev->iommufd_access = user;
return 0;
}
EXPORT_SYMBOL_GPL(vfio_iommufd_emulated_bind);
void vfio_iommufd_emulated_unbind(struct vfio_device *vdev)
{
lockdep_assert_held(&vdev->dev_set->lock);
if (vdev->iommufd_access) {
iommufd_access_destroy(vdev->iommufd_access);
vdev->iommufd_attached = false;
vdev->iommufd_access = NULL;
}
}
EXPORT_SYMBOL_GPL(vfio_iommufd_emulated_unbind);
int vfio_iommufd_emulated_attach_ioas(struct vfio_device *vdev, u32 *pt_id)
{
int rc;
lockdep_assert_held(&vdev->dev_set->lock);
if (vdev->iommufd_attached)
return -EBUSY;
rc = iommufd_access_attach(vdev->iommufd_access, *pt_id);
if (rc)
return rc;
vdev->iommufd_attached = true;
return 0;
}
EXPORT_SYMBOL_GPL(vfio_iommufd_emulated_attach_ioas);