Commit Graph

15 Commits

Author SHA1 Message Date
Linus Torvalds
48552153cf iommufd 6.15 merge window pull
Two significant new items:
 
 - Allow reporting IOMMU HW events to userspace when the events are clearly
   linked to a device. This is linked to the VIOMMU object and is intended to
   be used by a VMM to forward HW events to the virtual machine as part of
   emulating a vIOMMU. ARM SMMUv3 is the first driver to use this
   mechanism. Like the existing fault events the data is delivered through
   a simple FD returning event records on read().
 
 - PASID support in VFIO. "Process Address Space ID" is a PCI feature that
   allows the device to tag all PCI DMA operations with an ID. The IOMMU
   will then use the ID to select a unique translation for those DMAs. This
   is part of Intel's vIOMMU support as VT-D HW requires the hypervisor to
   manage each PASID entry. The support is generic so any VFIO user could
   attach any translation to a PASID, and the support should work on ARM
   SMMUv3 as well. AMD requires additional driver work.
 
 Some minor updates, along with fixes:
 
 - Prevent using nested parents with fault's, no driver support today
 
 - Put a single "cookie_type" value in the iommu_domain to indicate what
   owns the various opaque owner fields
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQRRRCHOFoQz/8F5bUaFwuHvBreFYQUCZ+q6NgAKCRCFwuHvBreF
 YZ3zAQDbl4/Z0O+CLN2AXq4Zeiyq1HTSoF94hzqmm7lQ17zTIwD8CCdyLXHvupaq
 tkBIv5IovpaxlrSk6M0kh2K8vPCk9Qk=
 =CIM3
 -----END PGP SIGNATURE-----

Merge tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd

Pull iommufd updates from Jason Gunthorpe:
 "Two significant new items:

   - Allow reporting IOMMU HW events to userspace when the events are
     clearly linked to a device.

     This is linked to the VIOMMU object and is intended to be used by a
     VMM to forward HW events to the virtual machine as part of
     emulating a vIOMMU. ARM SMMUv3 is the first driver to use this
     mechanism. Like the existing fault events the data is delivered
     through a simple FD returning event records on read().

   - PASID support in VFIO.

     The "Process Address Space ID" is a PCI feature that allows the
     device to tag all PCI DMA operations with an ID. The IOMMU will
     then use the ID to select a unique translation for those DMAs. This
     is part of Intel's vIOMMU support as VT-D HW requires the
     hypervisor to manage each PASID entry.

     The support is generic so any VFIO user could attach any
     translation to a PASID, and the support should work on ARM SMMUv3
     as well. AMD requires additional driver work.

  Some minor updates, along with fixes:

   - Prevent using nested parents with fault's, no driver support today

   - Put a single "cookie_type" value in the iommu_domain to indicate
     what owns the various opaque owner fields"

* tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd: (49 commits)
  iommufd: Test attach before detaching pasid
  iommufd: Fix iommu_vevent_header tables markup
  iommu: Convert unreachable() to BUG()
  iommufd: Balance veventq->num_events inc/dec
  iommufd: Initialize the flags of vevent in iommufd_viommu_report_event()
  iommufd/selftest: Add coverage for reporting max_pasid_log2 via IOMMU_HW_INFO
  iommufd: Extend IOMMU_GET_HW_INFO to report PASID capability
  vfio: VFIO_DEVICE_[AT|DE]TACH_IOMMUFD_PT support pasid
  vfio-iommufd: Support pasid [at|de]tach for physical VFIO devices
  ida: Add ida_find_first_range()
  iommufd/selftest: Add coverage for iommufd pasid attach/detach
  iommufd/selftest: Add test ops to test pasid attach/detach
  iommufd/selftest: Add a helper to get test device
  iommufd/selftest: Add set_dev_pasid in mock iommu
  iommufd: Allow allocating PASID-compatible domain
  iommu/vt-d: Add IOMMU_HWPT_ALLOC_PASID support
  iommufd: Enforce PASID-compatible domain for RID
  iommufd: Support pasid attach/replace
  iommufd: Enforce PASID-compatible domain in PASID path
  iommufd/device: Add pasid_attach array to track per-PASID attach
  ...
2025-04-01 18:03:46 -07:00
Yi Liu
8a9e1e773f iommu: Introduce a replace API for device pasid
Provide a high-level API to allow replacements of one domain with another
for specific pasid of a device. This is similar to
iommu_replace_group_handle() and it is expected to be used only by IOMMUFD.

Link: https://patch.msgid.link/r/20250321171940.7213-3-yi.l.liu@intel.com
Co-developed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2025-03-25 10:18:30 -03:00
Nicolin Chen
ec031e1b35 iommufd: Move iommufd_sw_msi and related functions to driver.c
To provide the iommufd_sw_msi() to the iommu core that is under a different
Kconfig, move it and its related functions to driver.c. Then, stub it into
the iommu-priv header. The iommufd_sw_msi_install() continues to be used by
iommufd internal, so put it in the private header.

Note that iommufd_sw_msi() will be called in the iommu core, replacing the
sw_msi function pointer. Given that IOMMU_API is "bool" in Kconfig, change
IOMMUFD_DRIVER_CORE to "bool" as well.

Since this affects the module size, here is before-n-after size comparison:
[Before]
   text	   data	    bss	    dec	    hex	filename
  18797	    848	     56	  19701	   4cf5	drivers/iommu/iommufd/device.o
    722	     44	      0	    766	    2fe	drivers/iommu/iommufd/driver.o
[After]
   text	   data	    bss	    dec	    hex	filename
  17735     808      56   18599    48a7 drivers/iommu/iommufd/device.o
   3020     180       0    3200     c80 drivers/iommu/iommufd/driver.o

Link: https://patch.msgid.link/r/374c159592dba7852bee20968f3f66fa0ee8ca93.1742871535.git.nicolinc@nvidia.com
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2025-03-25 10:18:19 -03:00
Robin Murphy
3832862eb9 iommu: Keep dev->iommu state consistent
At the moment, if of_iommu_configure() allocates dev->iommu itself via
iommu_fwspec_init(), then suffers a DT parsing failure, it cleans up the
fwspec but leaves the empty dev_iommu hanging around. So far this is
benign (if a tiny bit wasteful), but we'd like to be able to reason
about dev->iommu having a consistent and unambiguous lifecycle. Thus
make sure that the of_iommu cleanup undoes precisely whatever it did.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/d219663a3f23001f23d520a883ac622d70b4e642.1740753261.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2025-03-11 14:05:42 +01:00
Robin Murphy
29c6e1c2b9 iommu: Unexport iommu_fwspec_free()
The drivers doing their own fwspec parsing have no need to call
iommu_fwspec_free() since fwspecs were moved into dev_iommu, as
returning an error from .probe_device will tear down the whole lot
anyway. Move it into the private interface now that it only serves
for of_iommu to clean up in an error case.

I have no idea what mtk_v1 was doing in effectively guaranteeing
a NULL fwspec would be dereferenced if no "iommus" DT property was
found, so add a check for that to at least make the code look sane.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/36e245489361de2d13db22a510fa5c79e7126278.1740667667.git.robin.murphy@arm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2025-03-11 14:05:39 +01:00
Yi Liu
473ec072a6 iommu: Drop iommu_group_replace_domain()
iommufd does not use it now, so drop it.

Link: https://patch.msgid.link/r/20250226011849.5102-3-yi.l.liu@intel.com
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2025-02-28 10:07:14 -04:00
Will Deacon
74e54d532b Merge branch 'iommu/iommufd/attach-handles' into iommu/next
* iommu/iommufd/attach-handles:
  iommu: Extend domain attach group with handle support
  iommu: Add attach handle to struct iopf_group
  iommu: Remove sva handle list
  iommu: Introduce domain attachment handle
2024-07-12 16:57:42 +01:00
Robin Murphy
3e36c15fc1 iommu: Remove iommu_fwspec ops
The ops in iommu_fwspec are only needed for the early configuration and
probe process, and by now are easy enough to derive on-demand in those
couple of places which need them, so remove the redundant stored copy.

Tested-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/55c1410b2cd09531eab4f8e2f18f92a0faa0ea75.1719919669.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2024-07-04 14:36:04 +01:00
Robin Murphy
3f7c320916 iommu: Resolve fwspec ops automatically
There's no real need for callers to resolve ops from a fwnode in order
to then pass both to iommu_fwspec_init() - it's simpler and more sensible
for that to resolve the ops itself. This in turn means we can centralise
the notion of checking for a present driver, and enforce that fwspecs
aren't allocated unless and until we know they will be usable.

Also use this opportunity to modernise with some "new" helpers that
arrived shortly after this code was first written; the generic
fwnode_handle_get() clears up that ugly get/put mismatch, while
of_fwnode_handle() can now abstract those open-coded dereferences.

Tested-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/0e2727adeb8cd73274425322f2f793561bdc927e.1719919669.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2024-07-04 14:36:03 +01:00
Lu Baolu
8519e68983 iommu: Extend domain attach group with handle support
Unlike the SVA case where each PASID of a device has an SVA domain
attached to it, the I/O page faults are handled by the fault handler
of the SVA domain. The I/O page faults for a user page table might
be handled by the domain attached to RID or the domain attached to
the PASID, depending on whether the PASID table is managed by user
space or kernel. As a result, there is a need for the domain attach
group interfaces to have attach handle support. The attach handle
will be forwarded to the fault handler of the user domain.

Add some variants of the domain attaching group interfaces so that they
could support the attach handle and export them for use in IOMMUFD.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20240702063444.105814-5-baolu.lu@linux.intel.com
Signed-off-by: Will Deacon <will@kernel.org>
2024-07-04 13:46:18 +01:00
Lu Baolu
3e7f57d1ef iommu: Remove sva handle list
The struct sva_iommu represents an association between an SVA domain and
a PASID of a device. It's stored in the iommu group's pasid array and also
tracked by a list in the per-mm data structure. Removes duplicate tracking
of sva_iommu by eliminating the list.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20240702063444.105814-3-baolu.lu@linux.intel.com
Signed-off-by: Will Deacon <will@kernel.org>
2024-07-04 13:46:18 +01:00
Krzysztof Kozlowski
e70e9ecd7c iommu: constify pointer to bus_type
Make pointer to bus_type a pointer to const for code safety.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20240216144027.185959-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2024-03-01 13:46:57 +01:00
Yi Liu
92766e1b95 iommu: Move dev_iommu_ops() to private header
dev_iommu_ops() is essentially only used in iommu subsystem, so move to a
private header to avoid being abused by other drivers.

Link: https://lore.kernel.org/r/20230818101033.4100-2-yi.l.liu@intel.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>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2023-08-18 12:52:15 -03:00
Jason Gunthorpe
23a1b46f15 iommufd/selftest: Make the mock iommu driver into a real driver
I've avoided doing this because there is no way to make this happen
without an intrusion into the core code. Up till now this has avoided
needing the core code's probe path with some hackery - but now that
default domains are becoming mandatory it is unavoidable.

This became a serious problem when the core code stopped allowing
partially registered iommu drivers in commit 14891af379 ("iommu: Move
the iommu driver sysfs setup into iommu_init/deinit_device()") which
breaks the selftest. That series was developed along with a second series
that contained this patch so it was not noticed.

Make it so that iommufd selftest can create a real iommu driver and bind
it only to is own private bus. Add iommu_device_register_bus() as a core
code helper to make this possible. It simply sets the right pointers and
registers the notifier block. The mock driver then works like any normal
driver should, with probe triggered by the bus ops

When the bus->iommu_ops stuff is fully unwound we can probably do better
here and remove this special case.

Link: https://lore.kernel.org/r/15-v6-e8114faedade+425-iommu_all_defdom_jgg@nvidia.com
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2023-08-14 20:13:45 -03:00
Nicolin Chen
addb665924 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>
2023-07-26 10:20:11 -03:00