linux-stable/drivers/iommu/intel/Kconfig
Linus Torvalds 463f46e114 iommufd for 6.7
This branch has three new iommufd capabilities:
 
  - Dirty tracking for DMA. AMD/ARM/Intel CPUs can now record if a DMA
    writes to a page in the IOPTEs within the IO page table. This can be used
    to generate a record of what memory is being dirtied by DMA activities
    during a VM migration process. A VMM like qemu will combine the IOMMU
    dirty bits with the CPU's dirty log to determine what memory to
    transfer.
 
    VFIO already has a DMA dirty tracking framework that requires PCI
    devices to implement tracking HW internally. The iommufd version
    provides an alternative that the VMM can select, if available. The two
    are designed to have very similar APIs.
 
  - Userspace controlled attributes for hardware page
    tables (HWPT/iommu_domain). There are currently a few generic attributes
    for HWPTs (support dirty tracking, and parent of a nest). This is an
    entry point for the userspace iommu driver to control the HW in detail.
 
  - Nested translation support for HWPTs. This is a 2D translation scheme
    similar to the CPU where a DMA goes through a first stage to determine
    an intermediate address which is then translated trough a second stage
    to a physical address.
 
    Like for CPU translation the first stage table would exist in VM
    controlled memory and the second stage is in the kernel and matches the
    VM's guest to physical map.
 
    As every IOMMU has a unique set of parameter to describe the S1 IO page
    table and its associated parameters the userspace IOMMU driver has to
    marshal the information into the correct format.
 
    This is 1/3 of the feature, it allows creating the nested translation
    and binding it to VFIO devices, however the API to support IOTLB and
    ATC invalidation of the stage 1 io page table, and forwarding of IO
    faults are still in progress.
 
 The series includes AMD and Intel support for dirty tracking. Intel
 support for nested translation.
 
 Along the way are a number of internal items:
 
  - New iommu core items: ops->domain_alloc_user(), ops->set_dirty_tracking,
    ops->read_and_clear_dirty(), IOMMU_DOMAIN_NESTED, and iommu_copy_struct_from_user
 
  - UAF fix in iopt_area_split()
 
  - Spelling fixes and some test suite improvement
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Merge tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd

Pull iommufd updates from Jason Gunthorpe:
 "This brings three new iommufd capabilities:

   - Dirty tracking for DMA.

     AMD/ARM/Intel CPUs can now record if a DMA writes to a page in the
     IOPTEs within the IO page table. This can be used to generate a
     record of what memory is being dirtied by DMA activities during a
     VM migration process. A VMM like qemu will combine the IOMMU dirty
     bits with the CPU's dirty log to determine what memory to transfer.

     VFIO already has a DMA dirty tracking framework that requires PCI
     devices to implement tracking HW internally. The iommufd version
     provides an alternative that the VMM can select, if available. The
     two are designed to have very similar APIs.

   - Userspace controlled attributes for hardware page tables
     (HWPT/iommu_domain). There are currently a few generic attributes
     for HWPTs (support dirty tracking, and parent of a nest). This is
     an entry point for the userspace iommu driver to control the HW in
     detail.

   - Nested translation support for HWPTs. This is a 2D translation
     scheme similar to the CPU where a DMA goes through a first stage to
     determine an intermediate address which is then translated trough a
     second stage to a physical address.

     Like for CPU translation the first stage table would exist in VM
     controlled memory and the second stage is in the kernel and matches
     the VM's guest to physical map.

     As every IOMMU has a unique set of parameter to describe the S1 IO
     page table and its associated parameters the userspace IOMMU driver
     has to marshal the information into the correct format.

     This is 1/3 of the feature, it allows creating the nested
     translation and binding it to VFIO devices, however the API to
     support IOTLB and ATC invalidation of the stage 1 io page table,
     and forwarding of IO faults are still in progress.

  The series includes AMD and Intel support for dirty tracking. Intel
  support for nested translation.

  Along the way are a number of internal items:

   - New iommu core items: ops->domain_alloc_user(),
     ops->set_dirty_tracking, ops->read_and_clear_dirty(),
     IOMMU_DOMAIN_NESTED, and iommu_copy_struct_from_user

   - UAF fix in iopt_area_split()

   - Spelling fixes and some test suite improvement"

* tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd: (52 commits)
  iommufd: Organize the mock domain alloc functions closer to Joerg's tree
  iommufd/selftest: Fix page-size check in iommufd_test_dirty()
  iommufd: Add iopt_area_alloc()
  iommufd: Fix missing update of domains_itree after splitting iopt_area
  iommu/vt-d: Disallow read-only mappings to nest parent domain
  iommu/vt-d: Add nested domain allocation
  iommu/vt-d: Set the nested domain to a device
  iommu/vt-d: Make domain attach helpers to be extern
  iommu/vt-d: Add helper to setup pasid nested translation
  iommu/vt-d: Add helper for nested domain allocation
  iommu/vt-d: Extend dmar_domain to support nested domain
  iommufd: Add data structure for Intel VT-d stage-1 domain allocation
  iommu/vt-d: Enhance capability check for nested parent domain allocation
  iommufd/selftest: Add coverage for IOMMU_HWPT_ALLOC with nested HWPTs
  iommufd/selftest: Add nested domain allocation for mock domain
  iommu: Add iommu_copy_struct_from_user helper
  iommufd: Add a nested HW pagetable object
  iommu: Pass in parent domain with user_data to domain_alloc_user op
  iommufd: Share iommufd_hwpt_alloc with IOMMUFD_OBJ_HWPT_NESTED
  iommufd: Derive iommufd_hwpt_paging from iommufd_hw_pagetable
  ...
2023-11-01 16:44:56 -10:00

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# SPDX-License-Identifier: GPL-2.0-only
# Intel IOMMU support
config DMAR_TABLE
bool
config DMAR_PERF
bool
config DMAR_DEBUG
bool
config INTEL_IOMMU
bool "Support for Intel IOMMU using DMA Remapping Devices"
depends on PCI_MSI && ACPI && X86
select DMA_OPS
select IOMMU_API
select IOMMU_IOVA
select IOMMUFD_DRIVER if IOMMUFD
select NEED_DMA_MAP_STATE
select DMAR_TABLE
select SWIOTLB
select PCI_ATS
select PCI_PRI
select PCI_PASID
help
DMA remapping (DMAR) devices support enables independent address
translations for Direct Memory Access (DMA) from devices.
These DMA remapping devices are reported via ACPI tables
and include PCI device scope covered by these DMA
remapping devices.
if INTEL_IOMMU
config INTEL_IOMMU_DEBUGFS
bool "Export Intel IOMMU internals in Debugfs"
depends on IOMMU_DEBUGFS
select DMAR_PERF
select DMAR_DEBUG
help
!!!WARNING!!!
DO NOT ENABLE THIS OPTION UNLESS YOU REALLY KNOW WHAT YOU ARE DOING!!!
Expose Intel IOMMU internals in Debugfs.
This option is -NOT- intended for production environments, and should
only be enabled for debugging Intel IOMMU.
config INTEL_IOMMU_SVM
bool "Support for Shared Virtual Memory with Intel IOMMU"
depends on X86_64
select MMU_NOTIFIER
select IOMMU_SVA
help
Shared Virtual Memory (SVM) provides a facility for devices
to access DMA resources through process address space by
means of a Process Address Space ID (PASID).
config INTEL_IOMMU_DEFAULT_ON
bool "Enable Intel DMA Remapping Devices by default"
default y
help
Selecting this option will enable a DMAR device at boot time if
one is found. If this option is not selected, DMAR support can
be enabled by passing intel_iommu=on to the kernel.
config INTEL_IOMMU_BROKEN_GFX_WA
bool "Workaround broken graphics drivers (going away soon)"
depends on BROKEN && X86
help
Current Graphics drivers tend to use physical address
for DMA and avoid using DMA APIs. Setting this config
option permits the IOMMU driver to set a unity map for
all the OS-visible memory. Hence the driver can continue
to use physical addresses for DMA, at least until this
option is removed in the 2.6.32 kernel.
config INTEL_IOMMU_FLOPPY_WA
def_bool y
depends on X86
help
Floppy disk drivers are known to bypass DMA API calls
thereby failing to work when IOMMU is enabled. This
workaround will setup a 1:1 mapping for the first
16MiB to make floppy (an ISA device) work.
config INTEL_IOMMU_SCALABLE_MODE_DEFAULT_ON
bool "Enable Intel IOMMU scalable mode by default"
default y
help
Selecting this option will enable by default the scalable mode if
hardware presents the capability. The scalable mode is defined in
VT-d 3.0. The scalable mode capability could be checked by reading
/sys/devices/virtual/iommu/dmar*/intel-iommu/ecap. If this option
is not selected, scalable mode support could also be enabled by
passing intel_iommu=sm_on to the kernel. If not sure, please use
the default value.
config INTEL_IOMMU_PERF_EVENTS
def_bool y
bool "Intel IOMMU performance events"
depends on INTEL_IOMMU && PERF_EVENTS
help
Selecting this option will enable the performance monitoring
infrastructure in the Intel IOMMU. It collects information about
key events occurring during operation of the remapping hardware,
to aid performance tuning and debug. These are available on modern
processors which support Intel VT-d 4.0 and later.
endif # INTEL_IOMMU