It is more accurate to Check if KVM is enabled, instead of having the
architecture say so. Architectures always "have" KVM, so for example
checking CONFIG_HAVE_KVM in vfio code is pointless, but if KVM is disabled
in a specific build, there is no need for support code.
Alternatively, the #ifdefs could simply be deleted. However, this
would add dead code. For example, when KVM is disabled, there is no
need to include code in VFIO that uses symbol_get, as that symbol_get
would always fail.
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: x86@kernel.org
Cc: kbingham@kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
There are multiple devices, software and operational steps involved
in the process of live migration. An error occurred on any node may
cause the live migration operation to fail.
This complex process makes it very difficult to locate and analyze
the cause when the function fails.
In order to quickly locate the cause of the problem when the
live migration fails, I added a set of debugfs to the vfio
live migration driver.
+-------------------------------------------+
| |
| |
| QEMU |
| |
| |
+---+----------------------------+----------+
| ^ | ^
| | | |
| | | |
v | v |
+---------+--+ +---------+--+
|src vfio_dev| |dst vfio_dev|
+--+---------+ +--+---------+
| ^ | ^
| | | |
v | | |
+-----------+----+ +-----------+----+
|src dev debugfs | |dst dev debugfs |
+----------------+ +----------------+
The entire debugfs directory will be based on the definition of
the CONFIG_DEBUG_FS macro. If this macro is not enabled, the
interfaces in vfio.h will be empty definitions, and the creation
and initialization of the debugfs directory will not be executed.
vfio
|
+---<dev_name1>
| +---migration
| +--state
|
+---<dev_name2>
+---migration
+--state
debugfs will create a public root directory "vfio" file.
then create a dev_name() file for each live migration device.
First, create a unified state acquisition file of "migration"
in this device directory.
Then, create a public live migration state lookup file "state".
Signed-off-by: Longfang Liu <liulongfang@huawei.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20231106072225.28577-2-liulongfang@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
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
...
Have the IOVA bitmap exported symbols adhere to the IOMMUFD symbol
export convention i.e. using the IOMMUFD namespace. In doing so,
import the namespace in the current users. This means VFIO and the
vfio-pci drivers that use iova_bitmap_set().
Link: https://lore.kernel.org/r/20231024135109.73787-4-joao.m.martins@oracle.com
Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Brett Creeley <brett.creeley@amd.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
smatch reports:
vfio_combine_iova_ranges() error: uninitialized symbol 'last'.
vfio_combine_iova_ranges() error: potentially dereferencing uninitialized 'comb_end'.
vfio_combine_iova_ranges() error: potentially dereferencing uninitialized 'comb_start'.
These errors are only reachable via invalid input, in the case of
@last when we receive an empty rb-tree or for @comb_{start,end} if the
rb-tree is empty or otherwise fails to produce a second node that
reduces the gap. Add tests with warnings for these cases.
Reported-by: Cong Liu <liucong2@kylinos.cn>
Link: https://lore.kernel.org/all/20230920095532.88135-1-liucong2@kylinos.cn
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Brett Creeley <brett.creeley@amd.com>
Link: https://lore.kernel.org/r/20231002224325.3150842-1-alex.williamson@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This includes a shared branch with VFIO:
- Enhance VFIO_DEVICE_GET_PCI_HOT_RESET_INFO so it can work with iommufd
FDs, not just group FDs. This removes the last place in the uAPI that
required the group fd.
- Give VFIO a new device node /dev/vfio/devices/vfioX (the so called cdev
node) which is very similar to the FD from VFIO_GROUP_GET_DEVICE_FD.
The cdev is associated with the struct device that the VFIO driver is
bound to and shows up in sysfs in the normal way.
- Add a cdev IOCTL VFIO_DEVICE_BIND_IOMMUFD which allows a newly opened
/dev/vfio/devices/vfioX to be associated with an IOMMUFD, this replaces
the VFIO_GROUP_SET_CONTAINER flow.
- Add cdev IOCTLs VFIO_DEVICE_[AT|DE]TACH_IOMMUFD_PT to allow the IOMMU
translation the vfio_device is associated with to be changed. This is a
significant new feature for VFIO as previously each vfio_device was
fixed to a single translation.
The translation is under the control of iommufd, so it can be any of
the different translation modes that iommufd is learning to create.
At this point VFIO has compilation options to remove the legacy interfaces
and in modern mode it behaves like a normal driver subsystem. The
/dev/vfio/iommu and /dev/vfio/groupX nodes are not present and each
vfio_device only has a /dev/vfio/devices/vfioX cdev node that represents
the device.
On top of this is built some of the new iommufd functionality:
- IOMMU_HWPT_ALLOC allows userspace to directly create the low level
IO Page table objects and affiliate them with IOAS objects that hold
the translation mapping. This is the basic functionality for the
normal IOMMU_DOMAIN_PAGING domains.
- VFIO_DEVICE_ATTACH_IOMMUFD_PT can be used to replace the current
translation. This is wired up to through all the layers down to the
driver so the driver has the ability to implement a hitless
replacement. This is necessary to fully support guest behaviors when
emulating HW (eg guest atomic change of translation)
- IOMMU_GET_HW_INFO returns information about the IOMMU driver HW that
owns a VFIO device. This includes support for the Intel iommu, and
patches have been posted for all the other server IOMMU.
Along the way are a number of internal items:
- New iommufd kapis iommufd_ctx_has_group(), iommufd_device_to_ictx(),
iommufd_device_to_id(), iommufd_access_detach(), iommufd_ctx_from_fd(),
iommufd_device_replace()
- iommufd now internally tracks iommu_groups as it needs some per-group
data
- Reorganize how the internal hwpt allocation flows to have more robust
locking
- Improve the access interfaces to support detach and replace of an IOAS
from an access
- New selftests and a rework of how the selftests creates a mock iommu
driver to be more like a real iommu driver
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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:
"On top of the vfio updates is built some new iommufd functionality:
- IOMMU_HWPT_ALLOC allows userspace to directly create the low level
IO Page table objects and affiliate them with IOAS objects that
hold the translation mapping. This is the basic functionality for
the normal IOMMU_DOMAIN_PAGING domains.
- VFIO_DEVICE_ATTACH_IOMMUFD_PT can be used to replace the current
translation. This is wired up to through all the layers down to the
driver so the driver has the ability to implement a hitless
replacement. This is necessary to fully support guest behaviors
when emulating HW (eg guest atomic change of translation)
- IOMMU_GET_HW_INFO returns information about the IOMMU driver HW
that owns a VFIO device. This includes support for the Intel iommu,
and patches have been posted for all the other server IOMMU.
Along the way are a number of internal items:
- New iommufd kernel APIs: iommufd_ctx_has_group(),
iommufd_device_to_ictx(), iommufd_device_to_id(),
iommufd_access_detach(), iommufd_ctx_from_fd(),
iommufd_device_replace()
- iommufd now internally tracks iommu_groups as it needs some
per-group data
- Reorganize how the internal hwpt allocation flows to have more
robust locking
- Improve the access interfaces to support detach and replace of an
IOAS from an access
- New selftests and a rework of how the selftests creates a mock
iommu driver to be more like a real iommu driver"
Link: https://lore.kernel.org/lkml/ZO%2FTe6LU1ENf58ZW@nvidia.com/
* tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd: (34 commits)
iommufd/selftest: Don't leak the platform device memory when unloading the module
iommu/vt-d: Implement hw_info for iommu capability query
iommufd/selftest: Add coverage for IOMMU_GET_HW_INFO ioctl
iommufd: Add IOMMU_GET_HW_INFO
iommu: Add new iommu op to get iommu hardware information
iommu: Move dev_iommu_ops() to private header
iommufd: Remove iommufd_ref_to_users()
iommufd/selftest: Make the mock iommu driver into a real driver
vfio: Support IO page table replacement
iommufd/selftest: Add IOMMU_TEST_OP_ACCESS_REPLACE_IOAS coverage
iommufd: Add iommufd_access_replace() API
iommufd: Use iommufd_access_change_ioas in iommufd_access_destroy_object
iommufd: Add iommufd_access_change_ioas(_id) helpers
iommufd: Allow passing in iopt_access_list_id to iopt_remove_access()
vfio: Do not allow !ops->dma_unmap in vfio_pin/unpin_pages()
iommufd/selftest: Add a selftest for IOMMU_HWPT_ALLOC
iommufd/selftest: Return the real idev id from selftest mock_domain
iommufd: Add IOMMU_HWPT_ALLOC
iommufd/selftest: Test iommufd_device_replace()
iommufd: Make destroy_rwsem use a lock class per object type
...
The VFIO_DEVICE_GET_INFO, VFIO_DEVICE_GET_REGION_INFO, and
VFIO_IOMMU_GET_INFO ioctls fill in an info struct followed by capability
structs:
+------+---------+---------+-----+
| info | caps[0] | caps[1] | ... |
+------+---------+---------+-----+
Both the info and capability struct sizes are not always multiples of
sizeof(u64), leaving u64 fields in later capability structs misaligned.
Userspace applications currently need to handle misalignment manually in
order to support CPU architectures and programming languages with strict
alignment requirements.
Make life easier for userspace by ensuring alignment in the kernel. This
is done by padding info struct definitions and by copying out zeroes
after capability structs that are not aligned.
The new layout is as follows:
+------+---------+---+---------+-----+
| info | caps[0] | 0 | caps[1] | ... |
+------+---------+---+---------+-----+
In this example caps[0] has a size that is not multiples of sizeof(u64),
so zero padding is added to align the subsequent structure.
Adding zero padding between structs does not break the uapi. The memory
layout is specified by the info.cap_offset and caps[i].next fields
filled in by the kernel. Applications use these field values to locate
structs and are therefore unaffected by the addition of zero padding.
Note that code that copies out info structs with padding is updated to
always zero the struct and copy out as many bytes as userspace
requested. This makes the code shorter and avoids potential information
leaks by ensuring padding is initialized.
Originally-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20230809203144.2880050-1-stefanha@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Currently only Mellanox uses the combine_ranges function. The
new pds_vfio driver also needs this function. So, move it to
a common location for other vendor drivers to use.
Also, fix RCT ordering while moving/renaming the function.
Cc: Yishai Hadas <yishaih@nvidia.com>
Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Link: https://lore.kernel.org/r/20230807205755.29579-2-brett.creeley@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
A driver that doesn't implement ops->dma_unmap shouldn't be allowed to do
vfio_pin/unpin_pages(), though it can use vfio_dma_rw() to access an iova
range. Deny !ops->dma_unmap cases in vfio_pin/unpin_pages().
Link: https://lore.kernel.org/r/85d622729d8f2334b35d42f1c568df1ededb9171.1690523699.git.nicolinc@nvidia.com
Suggested-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
The IOMMU_CAP_CACHE_COHERENCY check only applies to the physical devices
that are IOMMU-backed. But it is now in the group code. If want to compile
vfio_group infrastructure out, this check needs to be moved out of the group
code.
Another reason for this change is to fail the device registration for the
physical devices that do not have IOMMU if the group code is not compiled
as the cdev interface does not support such devices.
Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Tested-by: Yanting Jiang <yanting.jiang@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230718135551.6592-25-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This adds ioctl for userspace to attach device cdev fd to and detach
from IOAS/hw_pagetable managed by iommufd.
VFIO_DEVICE_ATTACH_IOMMUFD_PT: attach vfio device to IOAS or hw_pagetable
managed by iommufd. Attach can be undo
by VFIO_DEVICE_DETACH_IOMMUFD_PT or device
fd close.
VFIO_DEVICE_DETACH_IOMMUFD_PT: detach vfio device from the current attached
IOAS or hw_pagetable managed by iommufd.
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Tested-by: Yanting Jiang <yanting.jiang@intel.com>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Tested-by: Terrence Xu <terrence.xu@intel.com>
Tested-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230718135551.6592-24-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This adds ioctl for userspace to bind device cdev fd to iommufd.
VFIO_DEVICE_BIND_IOMMUFD: bind device to an iommufd, hence gain DMA
control provided by the iommufd. open_device
op is called after bind_iommufd op.
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Tested-by: Yanting Jiang <yanting.jiang@intel.com>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Tested-by: Terrence Xu <terrence.xu@intel.com>
Tested-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20230718135551.6592-23-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This adds a local variable to store the user pointer cast result from arg.
It avoids the repeated casts in the code when more ioctls are added.
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Yanting Jiang <yanting.jiang@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230718135551.6592-22-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This saves some lines when adding the kvm get logic for the vfio_device
cdev path.
This also renames _vfio_device_get_kvm_safe() to be vfio_device_get_kvm_safe().
Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Tested-by: Yanting Jiang <yanting.jiang@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230718135551.6592-20-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This adds cdev support for vfio_device. It allows the user to directly
open a vfio device w/o using the legacy container/group interface, as a
prerequisite for supporting new iommu features like nested translation
and etc.
The device fd opened in this manner doesn't have the capability to access
the device as the fops open() doesn't open the device until the successful
VFIO_DEVICE_BIND_IOMMUFD ioctl which will be added in a later patch.
With this patch, devices registered to vfio core would have both the legacy
group and the new device interfaces created.
- group interface : /dev/vfio/$groupID
- device interface: /dev/vfio/devices/vfioX - normal device
("X" is a unique number across vfio devices)
For a given device, the user can identify the matching vfioX by searching
the vfio-dev folder under the sysfs path of the device. Take PCI device
(0000:6a:01.0) as an example, /sys/bus/pci/devices/0000\:6a\:01.0/vfio-dev/vfioX
implies the matching vfioX under /dev/vfio/devices/, and vfio-dev/vfioX/dev
contains the major:minor number of the matching /dev/vfio/devices/vfioX.
The user can get device fd by opening the /dev/vfio/devices/vfioX.
The vfio_device cdev logic in this patch:
*) __vfio_register_dev() path ends up doing cdev_device_add() for each
vfio_device if VFIO_DEVICE_CDEV configured.
*) vfio_unregister_group_dev() path does cdev_device_del();
cdev interface does not support noiommu devices, so VFIO only creates the
legacy group interface for the physical devices that do not have IOMMU.
noiommu users should use the legacy group interface.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Terrence Xu <terrence.xu@intel.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Tested-by: Yanting Jiang <yanting.jiang@intel.com>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Tested-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230718135551.6592-19-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
device_del() destroys the vfio-dev/vfioX under the sysfs for vfio_device.
There is no reason to keep it while the device is going to be unregistered.
This movement is also a preparation for adding vfio_device cdev. Kernel
should remove the cdev node of the vfio_device to avoid new registration
refcount increment while the device is going to be unregistered.
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Tested-by: Yanting Jiang <yanting.jiang@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230718135551.6592-18-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
.bind_iommufd() will generate an ID to represent this bond, which is
needed by userspace for further usage. Store devid in vfio_device_file
to avoid passing the pointer in multiple places.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Terrence Xu <terrence.xu@intel.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Tested-by: Yanting Jiang <yanting.jiang@intel.com>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Tested-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230718135551.6592-13-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
VFIO group has historically allowed multi-open of the device FD. This
was made secure because the "open" was executed via an ioctl to the
group FD which is itself only single open.
However, no known use of multiple device FDs today. It is kind of a
strange thing to do because new device FDs can naturally be created
via dup().
When we implement the new device uAPI (only used in cdev path) there is
no natural way to allow the device itself from being multi-opened in a
secure manner. Without the group FD we cannot prove the security context
of the opener.
Thus, when moving to the new uAPI we block the ability of opening
a device multiple times. Given old group path still allows it we store
a vfio_group pointer in struct vfio_device_file to differentiate.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Terrence Xu <terrence.xu@intel.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Tested-by: Yanting Jiang <yanting.jiang@intel.com>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Tested-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230718135551.6592-10-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Allow the vfio_device file to be in a state where the device FD is
opened but the device cannot be used by userspace (i.e. its .open_device()
hasn't been called). This inbetween state is not used when the device
FD is spawned from the group FD, however when we create the device FD
directly by opening a cdev it will be opened in the blocked state.
The reason for the inbetween state is that userspace only gets a FD but
doesn't gain access permission until binding the FD to an iommufd. So in
the blocked state, only the bind operation is allowed. Completing bind
will allow user to further access the device.
This is implemented by adding a flag in struct vfio_device_file to mark
the blocked state and using a simple smp_load_acquire() to obtain the
flag value and serialize all the device setup with the thread accessing
this device.
Following this lockless scheme, it can safely handle the device FD
unbound->bound but it cannot handle bound->unbound. To allow this we'd
need to add a lock on all the vfio ioctls which seems costly. So once
device FD is bound, it remains bound until the FD is closed.
Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Terrence Xu <terrence.xu@intel.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Tested-by: Yanting Jiang <yanting.jiang@intel.com>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Tested-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230718135551.6592-8-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This avoids passing too much parameters in multiple functions. Per the
input parameter change, rename the function to be vfio_df_open/close().
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Terrence Xu <terrence.xu@intel.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Tested-by: Yanting Jiang <yanting.jiang@intel.com>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Tested-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230718135551.6592-7-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This makes the vfio file kAPIs to accept vfio device files, also a
preparation for vfio device cdev support.
For the kvm set with vfio device file, kvm pointer is stored in struct
vfio_device_file, and use kvm_ref_lock to protect kvm set and kvm
pointer usage within VFIO. This kvm pointer will be set to vfio_device
after device file is bound to iommufd in the cdev path.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Terrence Xu <terrence.xu@intel.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Tested-by: Yanting Jiang <yanting.jiang@intel.com>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Tested-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230718135551.6592-4-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This prepares for making the below kAPIs to accept both group file
and device file instead of only vfio group file.
bool vfio_file_enforced_coherent(struct file *file);
void vfio_file_set_kvm(struct file *file, struct kvm *kvm);
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Terrence Xu <terrence.xu@intel.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Tested-by: Yanting Jiang <yanting.jiang@intel.com>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Tested-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230718135551.6592-3-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This is preparation for adding vfio device cdev support. vfio device
cdev requires:
1) A per device file memory to store the kvm pointer set by KVM. It will
be propagated to vfio_device:kvm after the device cdev file is bound
to an iommufd.
2) A mechanism to block device access through device cdev fd before it
is bound to an iommufd.
To address the above requirements, this adds a per device file structure
named vfio_device_file. For now, it's only a wrapper of struct vfio_device
pointer. Other fields will be added to this per file structure in future
commits.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Terrence Xu <terrence.xu@intel.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Tested-by: Yanting Jiang <yanting.jiang@intel.com>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Tested-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230718135551.6592-2-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
There are drivers that need to search vfio_device within a given dev_set.
e.g. vfio-pci. So add a helper.
vfio_pci_is_device_in_set() now returns -EBUSY in commit a882c16a2b
("vfio/pci: Change vfio_pci_try_bus_reset() to use the dev_set") where
it was trying to preserve the return of vfio_pci_try_zap_and_vma_lock_cb().
However, it makes more sense to return -ENODEV.
Suggested-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Yanting Jiang <yanting.jiang@intel.com>
Tested-by: Terrence Xu <terrence.xu@intel.com>
Tested-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230718105542.4138-8-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Here is the large set of driver core changes for 6.4-rc1.
Once again, a busy development cycle, with lots of changes happening in
the driver core in the quest to be able to move "struct bus" and "struct
class" into read-only memory, a task now complete with these changes.
This will make the future rust interactions with the driver core more
"provably correct" as well as providing more obvious lifetime rules for
all busses and classes in the kernel.
The changes required for this did touch many individual classes and
busses as many callbacks were changed to take const * parameters
instead. All of these changes have been submitted to the various
subsystem maintainers, giving them plenty of time to review, and most of
them actually did so.
Other than those changes, included in here are a small set of other
things:
- kobject logging improvements
- cacheinfo improvements and updates
- obligatory fw_devlink updates and fixes
- documentation updates
- device property cleanups and const * changes
- firwmare loader dependency fixes.
All of these have been in linux-next for a while with no reported
problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here is the large set of driver core changes for 6.4-rc1.
Once again, a busy development cycle, with lots of changes happening
in the driver core in the quest to be able to move "struct bus" and
"struct class" into read-only memory, a task now complete with these
changes.
This will make the future rust interactions with the driver core more
"provably correct" as well as providing more obvious lifetime rules
for all busses and classes in the kernel.
The changes required for this did touch many individual classes and
busses as many callbacks were changed to take const * parameters
instead. All of these changes have been submitted to the various
subsystem maintainers, giving them plenty of time to review, and most
of them actually did so.
Other than those changes, included in here are a small set of other
things:
- kobject logging improvements
- cacheinfo improvements and updates
- obligatory fw_devlink updates and fixes
- documentation updates
- device property cleanups and const * changes
- firwmare loader dependency fixes.
All of these have been in linux-next for a while with no reported
problems"
* tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (120 commits)
device property: make device_property functions take const device *
driver core: update comments in device_rename()
driver core: Don't require dynamic_debug for initcall_debug probe timing
firmware_loader: rework crypto dependencies
firmware_loader: Strip off \n from customized path
zram: fix up permission for the hot_add sysfs file
cacheinfo: Add use_arch[|_cache]_info field/function
arch_topology: Remove early cacheinfo error message if -ENOENT
cacheinfo: Check cache properties are present in DT
cacheinfo: Check sib_leaf in cache_leaves_are_shared()
cacheinfo: Allow early level detection when DT/ACPI info is missing/broken
cacheinfo: Add arm64 early level initializer implementation
cacheinfo: Add arch specific early level initializer
tty: make tty_class a static const structure
driver core: class: remove struct class_interface * from callbacks
driver core: class: mark the struct class in struct class_interface constant
driver core: class: make class_register() take a const *
driver core: class: mark class_release() as taking a const *
driver core: remove incorrect comment for device_create*
MIPS: vpe-cmp: remove module owner pointer from struct class usage.
...
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>
The module pointer in class_create() never actually did anything, and it
shouldn't have been requred to be set as a parameter even if it did
something. So just remove it and fix up all callers of the function in
the kernel tree at the same time.
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Link: https://lore.kernel.org/r/20230313181843.1207845-4-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
- Remove redundant resource check in vfio-platform. (Angus Chen)
- Use GFP_KERNEL_ACCOUNT for persistent userspace allocations, allowing
removal of arbitrary kernel limits in favor of cgroup control.
(Yishai Hadas)
- mdev tidy-ups, including removing the module-only build restriction
for sample drivers, Kconfig changes to select mdev support,
documentation movement to keep sample driver usage instructions with
sample drivers rather than with API docs, remove references to
out-of-tree drivers in docs. (Christoph Hellwig)
- Fix collateral breakages from mdev Kconfig changes. (Arnd Bergmann)
- Make mlx5 migration support match device support, improve source
and target flows to improve pre-copy support and reduce downtime.
(Yishai Hadas)
- Convert additional mdev sysfs case to use sysfs_emit(). (Bo Liu)
- Resolve copy-paste error in mdev mbochs sample driver Kconfig.
(Ye Xingchen)
- Avoid propagating missing reset error in vfio-platform if reset
requirement is relaxed by module option. (Tomasz Duszynski)
- Range size fixes in mlx5 variant driver for missed last byte and
stricter range calculation. (Yishai Hadas)
- Fixes to suspended vaddr support and locked_vm accounting, excluding
mdev configurations from the former due to potential to indefinitely
block kernel threads, fix underflow and restore locked_vm on new mm.
(Steve Sistare)
- Update outdated vfio documentation due to new IOMMUFD interfaces in
recent kernels. (Yi Liu)
- Resolve deadlock between group_lock and kvm_lock, finally.
(Matthew Rosato)
- Fix NULL pointer in group initialization error path with IOMMUFD.
(Yan Zhao)
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Merge tag 'vfio-v6.3-rc1' of https://github.com/awilliam/linux-vfio
Pull VFIO updates from Alex Williamson:
- Remove redundant resource check in vfio-platform (Angus Chen)
- Use GFP_KERNEL_ACCOUNT for persistent userspace allocations, allowing
removal of arbitrary kernel limits in favor of cgroup control (Yishai
Hadas)
- mdev tidy-ups, including removing the module-only build restriction
for sample drivers, Kconfig changes to select mdev support,
documentation movement to keep sample driver usage instructions with
sample drivers rather than with API docs, remove references to
out-of-tree drivers in docs (Christoph Hellwig)
- Fix collateral breakages from mdev Kconfig changes (Arnd Bergmann)
- Make mlx5 migration support match device support, improve source and
target flows to improve pre-copy support and reduce downtime (Yishai
Hadas)
- Convert additional mdev sysfs case to use sysfs_emit() (Bo Liu)
- Resolve copy-paste error in mdev mbochs sample driver Kconfig (Ye
Xingchen)
- Avoid propagating missing reset error in vfio-platform if reset
requirement is relaxed by module option (Tomasz Duszynski)
- Range size fixes in mlx5 variant driver for missed last byte and
stricter range calculation (Yishai Hadas)
- Fixes to suspended vaddr support and locked_vm accounting, excluding
mdev configurations from the former due to potential to indefinitely
block kernel threads, fix underflow and restore locked_vm on new mm
(Steve Sistare)
- Update outdated vfio documentation due to new IOMMUFD interfaces in
recent kernels (Yi Liu)
- Resolve deadlock between group_lock and kvm_lock, finally (Matthew
Rosato)
- Fix NULL pointer in group initialization error path with IOMMUFD (Yan
Zhao)
* tag 'vfio-v6.3-rc1' of https://github.com/awilliam/linux-vfio: (32 commits)
vfio: Fix NULL pointer dereference caused by uninitialized group->iommufd
docs: vfio: Update vfio.rst per latest interfaces
vfio: Update the kdoc for vfio_device_ops
vfio/mlx5: Fix range size calculation upon tracker creation
vfio: no need to pass kvm pointer during device open
vfio: fix deadlock between group lock and kvm lock
vfio: revert "iommu driver notify callback"
vfio/type1: revert "implement notify callback"
vfio/type1: revert "block on invalid vaddr"
vfio/type1: restore locked_vm
vfio/type1: track locked_vm per dma
vfio/type1: prevent underflow of locked_vm via exec()
vfio/type1: exclude mdevs from VFIO_UPDATE_VADDR
vfio: platform: ignore missing reset if disabled at module init
vfio/mlx5: Improve the target side flow to reduce downtime
vfio/mlx5: Improve the source side flow upon pre_copy
vfio/mlx5: Check whether VF is migratable
samples: fix the prompt about SAMPLE_VFIO_MDEV_MBOCHS
vfio/mdev: Use sysfs_emit() to instead of sprintf()
vfio-mdev: add back CONFIG_VFIO dependency
...
Nothing uses this value during vfio_device_open anymore so it's safe
to remove it.
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Tested-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230203215027.151988-3-mjrosato@linux.ibm.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
After 51cdc8bc12, we have another deadlock scenario between the
kvm->lock and the vfio group_lock with two different codepaths acquiring
the locks in different order. Specifically in vfio_open_device, vfio
holds the vfio group_lock when issuing device->ops->open_device but some
drivers (like vfio-ap) need to acquire kvm->lock during their open_device
routine; Meanwhile, kvm_vfio_release will acquire the kvm->lock first
before calling vfio_file_set_kvm which will acquire the vfio group_lock.
To resolve this, let's remove the need for the vfio group_lock from the
kvm_vfio_release codepath. This is done by introducing a new spinlock to
protect modifications to the vfio group kvm pointer, and acquiring a kvm
ref from within vfio while holding this spinlock, with the reference held
until the last close for the device in question.
Fixes: 51cdc8bc12 ("kvm/vfio: Fix potential deadlock on vfio group_lock")
Reported-by: Anthony Krowiak <akrowiak@linux.ibm.com>
Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Tested-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230203215027.151988-2-mjrosato@linux.ibm.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add a small amount of emulation to vfio_compat to accept the SET_IOMMU to
VFIO_NOIOMMU_IOMMU and have vfio just ignore iommufd if it is working on a
no-iommu enabled device.
Move the enable_unsafe_noiommu_mode module out of container.c into
vfio_main.c so that it is always available even if VFIO_CONTAINER=n.
This passes Alex's mini-test:
https://github.com/awilliam/tests/blob/master/vfio-noiommu-pci-device-open.c
Link: https://lore.kernel.org/r/0-v3-480cd64a16f7+1ad0-iommufd_noiommu_jgg@nvidia.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
- Replace deprecated git://github.com link in MAINTAINERS. (Palmer Dabbelt)
- Simplify vfio/mlx5 with module_pci_driver() helper. (Shang XiaoJing)
- Drop unnecessary buffer from ACPI call. (Rafael Mendonca)
- Correct latent missing include issue in iova-bitmap and fix support
for unaligned bitmaps. Follow-up with better fix through refactor.
(Joao Martins)
- Rework ccw mdev driver to split private data from parent structure,
better aligning with the mdev lifecycle and allowing us to remove
a temporary workaround. (Eric Farman)
- Add an interface to get an estimated migration data size for a device,
allowing userspace to make informed decisions, ex. more accurately
predicting VM downtime. (Yishai Hadas)
- Fix minor typo in vfio/mlx5 array declaration. (Yishai Hadas)
- Simplify module and Kconfig through consolidating SPAPR/EEH code and
config options and folding virqfd module into main vfio module.
(Jason Gunthorpe)
- Fix error path from device_register() across all vfio mdev and sample
drivers. (Alex Williamson)
- Define migration pre-copy interface and implement for vfio/mlx5
devices, allowing portions of the device state to be saved while the
device continues operation, towards reducing the stop-copy state
size. (Jason Gunthorpe, Yishai Hadas, Shay Drory)
- Implement pre-copy for hisi_acc devices. (Shameer Kolothum)
- Fixes to mdpy mdev driver remove path and error path on probe.
(Shang XiaoJing)
- vfio/mlx5 fixes for incorrect return after copy_to_user() fault and
incorrect buffer freeing. (Dan Carpenter)
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Merge tag 'vfio-v6.2-rc1' of https://github.com/awilliam/linux-vfio
Pull VFIO updates from Alex Williamson:
- Replace deprecated git://github.com link in MAINTAINERS (Palmer
Dabbelt)
- Simplify vfio/mlx5 with module_pci_driver() helper (Shang XiaoJing)
- Drop unnecessary buffer from ACPI call (Rafael Mendonca)
- Correct latent missing include issue in iova-bitmap and fix support
for unaligned bitmaps. Follow-up with better fix through refactor
(Joao Martins)
- Rework ccw mdev driver to split private data from parent structure,
better aligning with the mdev lifecycle and allowing us to remove a
temporary workaround (Eric Farman)
- Add an interface to get an estimated migration data size for a
device, allowing userspace to make informed decisions, ex. more
accurately predicting VM downtime (Yishai Hadas)
- Fix minor typo in vfio/mlx5 array declaration (Yishai Hadas)
- Simplify module and Kconfig through consolidating SPAPR/EEH code and
config options and folding virqfd module into main vfio module (Jason
Gunthorpe)
- Fix error path from device_register() across all vfio mdev and sample
drivers (Alex Williamson)
- Define migration pre-copy interface and implement for vfio/mlx5
devices, allowing portions of the device state to be saved while the
device continues operation, towards reducing the stop-copy state size
(Jason Gunthorpe, Yishai Hadas, Shay Drory)
- Implement pre-copy for hisi_acc devices (Shameer Kolothum)
- Fixes to mdpy mdev driver remove path and error path on probe (Shang
XiaoJing)
- vfio/mlx5 fixes for incorrect return after copy_to_user() fault and
incorrect buffer freeing (Dan Carpenter)
* tag 'vfio-v6.2-rc1' of https://github.com/awilliam/linux-vfio: (42 commits)
vfio/mlx5: error pointer dereference in error handling
vfio/mlx5: fix error code in mlx5vf_precopy_ioctl()
samples: vfio-mdev: Fix missing pci_disable_device() in mdpy_fb_probe()
hisi_acc_vfio_pci: Enable PRE_COPY flag
hisi_acc_vfio_pci: Move the dev compatibility tests for early check
hisi_acc_vfio_pci: Introduce support for PRE_COPY state transitions
hisi_acc_vfio_pci: Add support for precopy IOCTL
vfio/mlx5: Enable MIGRATION_PRE_COPY flag
vfio/mlx5: Fallback to STOP_COPY upon specific PRE_COPY error
vfio/mlx5: Introduce multiple loads
vfio/mlx5: Consider temporary end of stream as part of PRE_COPY
vfio/mlx5: Introduce vfio precopy ioctl implementation
vfio/mlx5: Introduce SW headers for migration states
vfio/mlx5: Introduce device transitions of PRE_COPY
vfio/mlx5: Refactor to use queue based data chunks
vfio/mlx5: Refactor migration file state
vfio/mlx5: Refactor MKEY usage
vfio/mlx5: Refactor PD usage
vfio/mlx5: Enforce a single SAVE command at a time
vfio: Extend the device migration protocol with PRE_COPY
...
The optional PRE_COPY states open the saving data transfer FD before
reaching STOP_COPY and allows the device to dirty track internal state
changes with the general idea to reduce the volume of data transferred
in the STOP_COPY stage.
While in PRE_COPY the device remains RUNNING, but the saving FD is open.
Only if the device also supports RUNNING_P2P can it support PRE_COPY_P2P,
which halts P2P transfers while continuing the saving FD.
PRE_COPY, with P2P support, requires the driver to implement 7 new arcs
and exists as an optional FSM branch between RUNNING and STOP_COPY:
RUNNING -> PRE_COPY -> PRE_COPY_P2P -> STOP_COPY
A new ioctl VFIO_MIG_GET_PRECOPY_INFO is provided to allow userspace to
query the progress of the precopy operation in the driver with the idea it
will judge to move to STOP_COPY at least once the initial data set is
transferred, and possibly after the dirty size has shrunk appropriately.
This ioctl is valid only in PRE_COPY states and kernel driver should
return -EINVAL from any other migration state.
Compared to the v1 clarification, STOP_COPY -> PRE_COPY is blocked
and to be defined in future.
We also split the pending_bytes report into the initial and sustaining
values, e.g.: initial_bytes and dirty_bytes.
initial_bytes: Amount of initial precopy data.
dirty_bytes: Device state changes relative to data previously retrieved.
These fields are not required to have any bearing to STOP_COPY phase.
It is recommended to leave PRE_COPY for STOP_COPY only after the
initial_bytes field reaches zero. Leaving PRE_COPY earlier might make
things slower.
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20221206083438.37807-3-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This is only 1.8k, putting it in its own module is not really
necessary. The kconfig infrastructure is still there to completely remove
it for systems that are trying for small footprint.
Put it in the main vfio.ko module now that kbuild can support multiple .c
files.
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Link: https://lore.kernel.org/r/5-v5-fc5346cacfd4+4c482-vfio_modules_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This prepares for compiling out vfio group after vfio device cdev is
added. No vfio_group decode code should be in vfio_main.c, and neither
device->group reference should be in vfio_main.c.
No functional change is intended.
Link: https://lore.kernel.org/r/20221201145535.589687-11-yi.l.liu@intel.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Yu He <yu.he@intel.com>
Tested-by: Lixiao Yang <lixiao.yang@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
To use group helpers instead of opening group related code in the
API. This prepares moving group specific code out of vfio_main.c.
Link: https://lore.kernel.org/r/20221201145535.589687-10-yi.l.liu@intel.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Lixiao Yang <lixiao.yang@intel.com>
Tested-by: Yu He <yu.he@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
This wraps the init/clean code of vfio group global variable to be
helpers, and prepares for further moving vfio group specific code into
separate file.
As container is used by group, so vfio_container_init/cleanup() is moved
into vfio_group_init/cleanup().
Link: https://lore.kernel.org/r/20221201145535.589687-9-yi.l.liu@intel.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Lixiao Yang <lixiao.yang@intel.com>
Tested-by: Yu He <yu.he@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
This refactor makes the vfio_device_open() to accept device, iommufd_ctx
pointer and kvm pointer. These parameters are generic items in today's
group path and future device cdev path. Caller of vfio_device_open()
should take care the necessary protections. e.g. the current group path
need to hold the group_lock to ensure the iommufd_ctx and kvm pointer are
valid.
This refactor also wraps the group spefcific codes in the device open and
close paths to be paired helpers like:
- vfio_device_group_open/close(): call vfio_device_open/close()
- vfio_device_group_use/unuse_iommu(): this pair is container specific.
iommufd vs. container is selected
in vfio_device_first_open().
Such helpers are supposed to be moved to group.c. While iommufd related
codes will be kept in the generic helpers since future device cdev path
also need to handle iommufd.
Link: https://lore.kernel.org/r/20221201145535.589687-8-yi.l.liu@intel.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Lixiao Yang <lixiao.yang@intel.com>
Tested-by: Yu He <yu.he@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Then move group related logic into vfio_device_open_file(). Accordingly
introduce a vfio_device_close() to pair up.
Link: https://lore.kernel.org/r/20221201145535.589687-7-yi.l.liu@intel.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Lixiao Yang <lixiao.yang@intel.com>
Tested-by: Yu He <yu.he@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
This makes the DMA unmap callback registration to container be consistent
across the vfio iommufd compat mode and the legacy container mode.
In the vfio iommufd compat mode, this registration is done in the
vfio_iommufd_bind() when creating access which has an unmap callback. This
is prior to calling the open_device() op. The existing mdev drivers have
been converted to be OK with this order. So it is ok to swap the order of
vfio_device_container_register() and open_device() for legacy mode.
This also prepares for further moving group specific code into separate
source file.
Link: https://lore.kernel.org/r/20221201145535.589687-6-yi.l.liu@intel.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Lixiao Yang <lixiao.yang@intel.com>
Tested-by: Yu He <yu.he@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
This avoids referencing device->group in __vfio_register_dev().
Link: https://lore.kernel.org/r/20221201145535.589687-5-yi.l.liu@intel.com
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Lixiao Yang <lixiao.yang@intel.com>
Tested-by: Yu He <yu.he@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
This avoids decoding group fields in the common functions used by
vfio_device registration, and prepares for further moving the vfio group
specific code into separate file.
Link: https://lore.kernel.org/r/20221201145535.589687-4-yi.l.liu@intel.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Lixiao Yang <lixiao.yang@intel.com>
Tested-by: Yu He <yu.he@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
This avoids opening group specific code in __vfio_register_dev() for the
sanity check if an (existing) group is not corrupted by having two copies
of the same struct device in it. It also simplifies the error unwind for
this sanity check since the failure can be detected in the group
allocation.
This also prepares for moving the group specific code into separate
group.c.
Grabbed from:
https://lore.kernel.org/kvm/20220922152338.2a2238fe.alex.williamson@redhat.com/
Link: https://lore.kernel.org/r/20221201145535.589687-3-yi.l.liu@intel.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Lixiao Yang <lixiao.yang@intel.com>
Tested-by: Yu He <yu.he@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
The vfio.group_lock is now only used to serialize vfio_group creation and
destruction, we don't need a micro-optimization of searching, unlocking,
then allocating and searching again. Just hold the lock the whole time.
Grabbed from:
https://lore.kernel.org/kvm/20220922152338.2a2238fe.alex.williamson@redhat.com/
Link: https://lore.kernel.org/r/20221201145535.589687-2-yi.l.liu@intel.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Lixiao Yang <lixiao.yang@intel.com>
Tested-by: Yu He <yu.he@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Resolve conflicts in drivers/vfio/vfio_main.c by using the iommfd version.
The rc fix was done a different way when iommufd patches reworked this
code.
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
The miscdev is in container.c, so should these related MODULE_ALIAS
statements. This is necessary for the next patch to be able to fully
disable /dev/vfio/vfio.
Fixes: cdc71fe4ec ("vfio: Move container code into drivers/vfio/container.c")
Link: https://lore.kernel.org/r/8-v4-42cd2eb0e3eb+335a-vfio_iommufd_jgg@nvidia.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Yi Liu <yi.l.liu@intel.com>
Tested-by: Lixiao Yang <lixiao.yang@intel.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Tested-by: Yu He <yu.he@intel.com>
Reported-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Emulated VFIO devices are calling vfio_register_emulated_iommu_dev() and
consist of all the mdev drivers.
Like the physical drivers, support for iommufd is provided by the driver
supplying the correct standard ops. Provide ops from the core that
duplicate what vfio_register_emulated_iommu_dev() does.
Emulated drivers are where it is more likely to see variation in the
iommfd support ops. For instance IDXD will probably need to setup both a
iommfd_device context linked to a PASID and an iommufd_access context to
support all their mdev operations.
Link: https://lore.kernel.org/r/7-v4-42cd2eb0e3eb+335a-vfio_iommufd_jgg@nvidia.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Yi Liu <yi.l.liu@intel.com>
Tested-by: Lixiao Yang <lixiao.yang@intel.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Tested-by: Yu He <yu.he@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
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: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Yi Liu <yi.l.liu@intel.com>
Tested-by: Lixiao Yang <lixiao.yang@intel.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Tested-by: Yu He <yu.he@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
