1
linux/drivers/iommu/iommu-priv.h

50 lines
1.7 KiB
C
Raw Permalink Normal View History

iommu: Introduce a new iommu_group_replace_domain() API qemu has a need to replace the translations associated with a domain when the guest does large-scale operations like switching between an IDENTITY domain and, say, dma-iommu.c. Currently, it does this by replacing all the mappings in a single domain, but this is very inefficient and means that domains have to be per-device rather than per-translation. Provide a high-level API to allow replacements of one domain with another. This is similar to a detach/attach cycle except it doesn't force the group to go to the blocking domain in-between. By removing this forced blocking domain the iommu driver has the opportunity to implement a non-disruptive replacement of the domain to the greatest extent its hardware allows. This allows the qemu emulation of the vIOMMU to be more complete, as real hardware often has a non-distruptive replacement capability. It could be possible to address this by simply removing the protection from the iommu_attach_group(), but it is not so clear if that is safe for the few users. Thus, add a new API to serve this new purpose. All drivers are already required to support changing between active UNMANAGED domains when using their attach_dev ops. This API is expected to be used only by IOMMUFD, so add to the iommu-priv header and mark it as IOMMUFD_INTERNAL. Link: https://lore.kernel.org/r/13-v8-6659224517ea+532-iommufd_alloc_jgg@nvidia.com Suggested-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com> Tested-by: Nicolin Chen <nicolinc@nvidia.com> Signed-off-by: Nicolin Chen <nicolinc@nvidia.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2023-07-17 11:12:09 -07:00
/* SPDX-License-Identifier: GPL-2.0-only */
/* Copyright (c) 2023, NVIDIA CORPORATION & AFFILIATES.
*/
iommu: Introduce a new iommu_group_replace_domain() API qemu has a need to replace the translations associated with a domain when the guest does large-scale operations like switching between an IDENTITY domain and, say, dma-iommu.c. Currently, it does this by replacing all the mappings in a single domain, but this is very inefficient and means that domains have to be per-device rather than per-translation. Provide a high-level API to allow replacements of one domain with another. This is similar to a detach/attach cycle except it doesn't force the group to go to the blocking domain in-between. By removing this forced blocking domain the iommu driver has the opportunity to implement a non-disruptive replacement of the domain to the greatest extent its hardware allows. This allows the qemu emulation of the vIOMMU to be more complete, as real hardware often has a non-distruptive replacement capability. It could be possible to address this by simply removing the protection from the iommu_attach_group(), but it is not so clear if that is safe for the few users. Thus, add a new API to serve this new purpose. All drivers are already required to support changing between active UNMANAGED domains when using their attach_dev ops. This API is expected to be used only by IOMMUFD, so add to the iommu-priv header and mark it as IOMMUFD_INTERNAL. Link: https://lore.kernel.org/r/13-v8-6659224517ea+532-iommufd_alloc_jgg@nvidia.com Suggested-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com> Tested-by: Nicolin Chen <nicolinc@nvidia.com> Signed-off-by: Nicolin Chen <nicolinc@nvidia.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2023-07-17 11:12:09 -07:00
#ifndef __LINUX_IOMMU_PRIV_H
#define __LINUX_IOMMU_PRIV_H
#include <linux/iommu.h>
static inline const struct iommu_ops *dev_iommu_ops(struct device *dev)
{
/*
* Assume that valid ops must be installed if iommu_probe_device()
* has succeeded. The device ops are essentially for internal use
* within the IOMMU subsystem itself, so we should be able to trust
* ourselves not to misuse the helper.
*/
return dev->iommu->iommu_dev->ops;
}
const struct iommu_ops *iommu_ops_from_fwnode(const struct fwnode_handle *fwnode);
static inline const struct iommu_ops *iommu_fwspec_ops(struct iommu_fwspec *fwspec)
{
return iommu_ops_from_fwnode(fwspec ? fwspec->iommu_fwnode : NULL);
}
iommu: Introduce a new iommu_group_replace_domain() API qemu has a need to replace the translations associated with a domain when the guest does large-scale operations like switching between an IDENTITY domain and, say, dma-iommu.c. Currently, it does this by replacing all the mappings in a single domain, but this is very inefficient and means that domains have to be per-device rather than per-translation. Provide a high-level API to allow replacements of one domain with another. This is similar to a detach/attach cycle except it doesn't force the group to go to the blocking domain in-between. By removing this forced blocking domain the iommu driver has the opportunity to implement a non-disruptive replacement of the domain to the greatest extent its hardware allows. This allows the qemu emulation of the vIOMMU to be more complete, as real hardware often has a non-distruptive replacement capability. It could be possible to address this by simply removing the protection from the iommu_attach_group(), but it is not so clear if that is safe for the few users. Thus, add a new API to serve this new purpose. All drivers are already required to support changing between active UNMANAGED domains when using their attach_dev ops. This API is expected to be used only by IOMMUFD, so add to the iommu-priv header and mark it as IOMMUFD_INTERNAL. Link: https://lore.kernel.org/r/13-v8-6659224517ea+532-iommufd_alloc_jgg@nvidia.com Suggested-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com> Tested-by: Nicolin Chen <nicolinc@nvidia.com> Signed-off-by: Nicolin Chen <nicolinc@nvidia.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2023-07-17 11:12:09 -07:00
int iommu_group_replace_domain(struct iommu_group *group,
struct iommu_domain *new_domain);
int iommu_device_register_bus(struct iommu_device *iommu,
const struct iommu_ops *ops,
const struct bus_type *bus,
struct notifier_block *nb);
void iommu_device_unregister_bus(struct iommu_device *iommu,
const struct bus_type *bus,
struct notifier_block *nb);
struct iommu_attach_handle *iommu_attach_handle_get(struct iommu_group *group,
ioasid_t pasid,
unsigned int type);
int iommu_attach_group_handle(struct iommu_domain *domain,
struct iommu_group *group,
struct iommu_attach_handle *handle);
void iommu_detach_group_handle(struct iommu_domain *domain,
struct iommu_group *group);
int iommu_replace_group_handle(struct iommu_group *group,
struct iommu_domain *new_domain,
struct iommu_attach_handle *handle);
iommu: Introduce a new iommu_group_replace_domain() API qemu has a need to replace the translations associated with a domain when the guest does large-scale operations like switching between an IDENTITY domain and, say, dma-iommu.c. Currently, it does this by replacing all the mappings in a single domain, but this is very inefficient and means that domains have to be per-device rather than per-translation. Provide a high-level API to allow replacements of one domain with another. This is similar to a detach/attach cycle except it doesn't force the group to go to the blocking domain in-between. By removing this forced blocking domain the iommu driver has the opportunity to implement a non-disruptive replacement of the domain to the greatest extent its hardware allows. This allows the qemu emulation of the vIOMMU to be more complete, as real hardware often has a non-distruptive replacement capability. It could be possible to address this by simply removing the protection from the iommu_attach_group(), but it is not so clear if that is safe for the few users. Thus, add a new API to serve this new purpose. All drivers are already required to support changing between active UNMANAGED domains when using their attach_dev ops. This API is expected to be used only by IOMMUFD, so add to the iommu-priv header and mark it as IOMMUFD_INTERNAL. Link: https://lore.kernel.org/r/13-v8-6659224517ea+532-iommufd_alloc_jgg@nvidia.com Suggested-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com> Tested-by: Nicolin Chen <nicolinc@nvidia.com> Signed-off-by: Nicolin Chen <nicolinc@nvidia.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2023-07-17 11:12:09 -07:00
#endif /* __LINUX_IOMMU_PRIV_H */