Commit Graph

1096 Commits

Author SHA1 Message Date
Linus Torvalds
4debf77169 iommufd for 6.6
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
  ...
2023-08-30 20:41:37 -07:00
Linus Torvalds
ec0e2dc810 VFIO updates for v6.6-rc1
- VFIO direct character device (cdev) interface support.  This extracts
    the vfio device fd from the container and group model, and is intended
    to be the native uAPI for use with IOMMUFD. (Yi Liu)
 
  - Enhancements to the PCI hot reset interface in support of cdev usage.
    (Yi Liu)
 
  - Fix a potential race between registering and unregistering vfio files
    in the kvm-vfio interface and extend use of a lock to avoid extra
    drop and acquires. (Dmitry Torokhov)
 
  - A new vfio-pci variant driver for the AMD/Pensando Distributed Services
    Card (PDS) Ethernet device, supporting live migration. (Brett Creeley)
 
  - Cleanups to remove redundant owner setup in cdx and fsl bus drivers,
    and simplify driver init/exit in fsl code. (Li Zetao)
 
  - Fix uninitialized hole in data structure and pad capability structures
    for alignment. (Stefan Hajnoczi)
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Merge tag 'vfio-v6.6-rc1' of https://github.com/awilliam/linux-vfio

Pull VFIO updates from Alex Williamson:

 - VFIO direct character device (cdev) interface support. This extracts
   the vfio device fd from the container and group model, and is
   intended to be the native uAPI for use with IOMMUFD (Yi Liu)

 - Enhancements to the PCI hot reset interface in support of cdev usage
   (Yi Liu)

 - Fix a potential race between registering and unregistering vfio files
   in the kvm-vfio interface and extend use of a lock to avoid extra
   drop and acquires (Dmitry Torokhov)

 - A new vfio-pci variant driver for the AMD/Pensando Distributed
   Services Card (PDS) Ethernet device, supporting live migration (Brett
   Creeley)

 - Cleanups to remove redundant owner setup in cdx and fsl bus drivers,
   and simplify driver init/exit in fsl code (Li Zetao)

 - Fix uninitialized hole in data structure and pad capability
   structures for alignment (Stefan Hajnoczi)

* tag 'vfio-v6.6-rc1' of https://github.com/awilliam/linux-vfio: (53 commits)
  vfio/pds: Send type for SUSPEND_STATUS command
  vfio/pds: fix return value in pds_vfio_get_lm_file()
  pds_core: Fix function header descriptions
  vfio: align capability structures
  vfio/type1: fix cap_migration information leak
  vfio/fsl-mc: Use module_fsl_mc_driver macro to simplify the code
  vfio/cdx: Remove redundant initialization owner in vfio_cdx_driver
  vfio/pds: Add Kconfig and documentation
  vfio/pds: Add support for firmware recovery
  vfio/pds: Add support for dirty page tracking
  vfio/pds: Add VFIO live migration support
  vfio/pds: register with the pds_core PF
  pds_core: Require callers of register/unregister to pass PF drvdata
  vfio/pds: Initial support for pds VFIO driver
  vfio: Commonize combine_ranges for use in other VFIO drivers
  kvm/vfio: avoid bouncing the mutex when adding and deleting groups
  kvm/vfio: ensure kvg instance stays around in kvm_vfio_group_add()
  docs: vfio: Add vfio device cdev description
  vfio: Compile vfio_group infrastructure optionally
  vfio: Move the IOMMU_CAP_CACHE_COHERENCY check in __vfio_register_dev()
  ...
2023-08-30 20:36:01 -07:00
Brett Creeley
642265e22e vfio/pds: Send type for SUSPEND_STATUS command
Commit bb500dbe2a ("vfio/pds: Add VFIO live migration support")
added live migration support for the pds-vfio-pci driver. When
sending the SUSPEND command to the device, the driver sets the
type of suspend (i.e. P2P or FULL). However, the driver isn't
sending the type of suspend for the SUSPEND_STATUS command, which
will result in failures. Fix this by also sending the suspend type
in the SUSPEND_STATUS command.

Fixes: bb500dbe2a ("vfio/pds: Add VFIO live migration support")
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>
Link: https://lore.kernel.org/r/20230821184215.34564-1-brett.creeley@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-08-22 13:11:57 -06:00
Yang Yingliang
2d12d18f14 vfio/pds: fix return value in pds_vfio_get_lm_file()
anon_inode_getfile() never returns NULL pointer, it will return
ERR_PTR() when it fails, so replace the check with IS_ERR().

Fixes: bb500dbe2a ("vfio/pds: Add VFIO live migration support")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Brett Creeley <brett.creeley@amd.com>
Link: https://lore.kernel.org/r/20230819023716.3469037-1-yangyingliang@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-08-21 08:50:33 -06:00
Stefan Hajnoczi
a881b49694 vfio: align capability structures
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>
2023-08-17 12:17:44 -06:00
Stefan Hajnoczi
cd24e2a60a vfio/type1: fix cap_migration information leak
Fix an information leak where an uninitialized hole in struct
vfio_iommu_type1_info_cap_migration on the stack is exposed to userspace.

The definition of struct vfio_iommu_type1_info_cap_migration contains a hole as
shown in this pahole(1) output:

  struct vfio_iommu_type1_info_cap_migration {
          struct vfio_info_cap_header header;              /*     0     8 */
          __u32                      flags;                /*     8     4 */

          /* XXX 4 bytes hole, try to pack */

          __u64                      pgsize_bitmap;        /*    16     8 */
          __u64                      max_dirty_bitmap_size; /*    24     8 */

          /* size: 32, cachelines: 1, members: 4 */
          /* sum members: 28, holes: 1, sum holes: 4 */
          /* last cacheline: 32 bytes */
  };

The cap_mig variable is filled in without initializing the hole:

  static int vfio_iommu_migration_build_caps(struct vfio_iommu *iommu,
                         struct vfio_info_cap *caps)
  {
      struct vfio_iommu_type1_info_cap_migration cap_mig;

      cap_mig.header.id = VFIO_IOMMU_TYPE1_INFO_CAP_MIGRATION;
      cap_mig.header.version = 1;

      cap_mig.flags = 0;
      /* support minimum pgsize */
      cap_mig.pgsize_bitmap = (size_t)1 << __ffs(iommu->pgsize_bitmap);
      cap_mig.max_dirty_bitmap_size = DIRTY_BITMAP_SIZE_MAX;

      return vfio_info_add_capability(caps, &cap_mig.header, sizeof(cap_mig));
  }

The structure is then copied to a temporary location on the heap. At this point
it's already too late and ioctl(VFIO_IOMMU_GET_INFO) copies it to userspace
later:

  int vfio_info_add_capability(struct vfio_info_cap *caps,
                   struct vfio_info_cap_header *cap, size_t size)
  {
      struct vfio_info_cap_header *header;

      header = vfio_info_cap_add(caps, size, cap->id, cap->version);
      if (IS_ERR(header))
          return PTR_ERR(header);

      memcpy(header + 1, cap + 1, size - sizeof(*header));

      return 0;
  }

This issue was found by code inspection.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Fixes: ad721705d0 ("vfio iommu: Add migration capability to report supported features")
Link: https://lore.kernel.org/r/20230801155352.1391945-1-stefanha@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-08-16 12:25:35 -06:00
Li Zetao
6c092088fa vfio/fsl-mc: Use module_fsl_mc_driver macro to simplify the code
Use the module_fsl_mc_driver macro to simplify the code and
remove redundant initialization owner in vfio_fsl_mc_driver.

Signed-off-by: Li Zetao <lizetao1@huawei.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20230809131536.4021639-1-lizetao1@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-08-16 11:14:15 -06:00
Li Zetao
d7955ce40e vfio/cdx: Remove redundant initialization owner in vfio_cdx_driver
The cdx_driver_register() will set "THIS_MODULE" to driver.owner when
register a cdx_driver driver, so it is redundant initialization to set
driver.owner in the statement. Remove it for clean code.

Signed-off-by: Li Zetao <lizetao1@huawei.com>
Acked-by: Nikhil Agarwal <nikhil.agarwal@amd.com>
Link: https://lore.kernel.org/r/20230808020937.2975196-1-lizetao1@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-08-16 11:13:51 -06:00
Brett Creeley
fc9da66103 vfio/pds: Add Kconfig and documentation
Add Kconfig entries and pds-vfio-pci.rst. Also, add an entry in the
MAINTAINERS file for this new driver.

It's not clear where documentation for vendor specific VFIO
drivers should live, so just re-use the current amd
ethernet location.

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: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20230807205755.29579-9-brett.creeley@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-08-16 10:54:54 -06:00
Brett Creeley
7dabb1bcd1 vfio/pds: Add support for firmware recovery
It's possible that the device firmware crashes and is able to recover
due to some configuration and/or other issue. If a live migration
is in progress while the firmware crashes, the live migration will
fail. However, the VF PCI device should still be functional post
crash recovery and subsequent migrations should go through as
expected.

When the pds_core device notices that firmware crashes it sends an
event to all its client drivers. When the pds_vfio driver receives
this event while migration is in progress it will request a deferred
reset on the next migration state transition. This state transition
will report failure as well as any subsequent state transition
requests from the VMM/VFIO. Based on uapi/vfio.h the only way out of
VFIO_DEVICE_STATE_ERROR is by issuing VFIO_DEVICE_RESET. Once this
reset is done, the migration state will be reset to
VFIO_DEVICE_STATE_RUNNING and migration can be performed.

If the event is received while no migration is in progress (i.e.
the VM is in normal operating mode), then no actions are taken
and the migration state remains VFIO_DEVICE_STATE_RUNNING.

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: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20230807205755.29579-8-brett.creeley@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-08-16 10:54:54 -06:00
Brett Creeley
f232836a91 vfio/pds: Add support for dirty page tracking
In order to support dirty page tracking, the driver has to implement
the VFIO subsystem's vfio_log_ops. This includes log_start, log_stop,
and log_read_and_clear.

All of the tracker resources are allocated and dirty tracking on the
device is started during log_start. The resources are cleaned up and
dirty tracking on the device is stopped during log_stop. The dirty
pages are determined and reported during log_read_and_clear.

In order to support these callbacks admin queue commands are used.
All of the adminq queue command structures and implementations
are included as part of this patch.

PDS_LM_CMD_DIRTY_STATUS is added to query the current status of
dirty tracking on the device. This includes if it's enabled (i.e.
number of regions being tracked from the device's perspective) and
the maximum number of regions supported from the device's perspective.

PDS_LM_CMD_DIRTY_ENABLE is added to enable dirty tracking on the
specified number of regions and their iova ranges.

PDS_LM_CMD_DIRTY_DISABLE is added to disable dirty tracking for all
regions on the device.

PDS_LM_CMD_READ_SEQ and PDS_LM_CMD_DIRTY_WRITE_ACK are added to
support reading and acknowledging the currently dirtied pages.

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/20230807205755.29579-7-brett.creeley@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-08-16 10:54:46 -06:00
Brett Creeley
bb500dbe2a vfio/pds: Add VFIO live migration support
Add live migration support via the VFIO subsystem. The migration
implementation aligns with the definition from uapi/vfio.h and uses
the pds_core PF's adminq for device configuration.

The ability to suspend, resume, and transfer VF device state data is
included along with the required admin queue command structures and
implementations.

PDS_LM_CMD_SUSPEND and PDS_LM_CMD_SUSPEND_STATUS are added to support
the VF device suspend operation.

PDS_LM_CMD_RESUME is added to support the VF device resume operation.

PDS_LM_CMD_STATE_SIZE is added to determine the exact size of the VF
device state data.

PDS_LM_CMD_SAVE is added to get the VF device state data.

PDS_LM_CMD_RESTORE is added to restore the VF device with the
previously saved data from PDS_LM_CMD_SAVE.

PDS_LM_CMD_HOST_VF_STATUS is added to notify the DSC/firmware when
a migration is in/not-in progress from the host's perspective. The
DSC/firmware can use this to clear/setup any necessary state related
to a migration.

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: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20230807205755.29579-6-brett.creeley@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-08-16 10:53:26 -06:00
Brett Creeley
63f77a7161 vfio/pds: register with the pds_core PF
The pds_core driver will supply adminq services, so find the PF
and register with the DSC services.

Use the following commands to enable a VF:
echo 1 > /sys/bus/pci/drivers/pds_core/$PF_BDF/sriov_numvfs

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: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20230807205755.29579-5-brett.creeley@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-08-16 10:53:20 -06:00
Brett Creeley
38fe3975b4 vfio/pds: Initial support for pds VFIO driver
This is the initial framework for the new pds-vfio-pci device driver.
This does the very basics of registering the PDS PCI device and
configuring it as a VFIO PCI device.

With this change, the VF device can be bound to the pds-vfio-pci driver
on the host and presented to the VM as an ethernet VF.

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: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20230807205755.29579-3-brett.creeley@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-08-16 10:53:00 -06:00
Brett Creeley
9a4087fab3 vfio: Commonize combine_ranges for use in other VFIO drivers
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>
2023-08-16 10:52:23 -06:00
Maher Sanalla
f14c1a14e6 net/mlx5: Allocate completion EQs dynamically
This commit enables the dynamic allocation of EQs at runtime, allowing
for more flexibility in managing completion EQs and reducing the memory
overhead of driver load. Whenever a CQ is created for a given vector
index, the driver will lookup to see if there is an already mapped
completion EQ for that vector, if so, utilize it. Otherwise, allocate a
new EQ on demand and then utilize it for the CQ completion events.

Add a protection lock to the EQ table to protect from concurrent EQ
creation attempts.

While at it, replace mlx5_vector2irqn()/mlx5_vector2eqn() with
mlx5_comp_eqn_get() and mlx5_comp_irqn_get() which will allocate an
EQ on demand if no EQ is found for the given vector.

Signed-off-by: Maher Sanalla <msanalla@nvidia.com>
Reviewed-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
2023-08-07 10:53:52 -07:00
Maher Sanalla
674dd4e2e0 net/mlx5: Rename mlx5_comp_vectors_count() to mlx5_comp_vectors_max()
To accurately represent its purpose, rename the function that retrieves
the value of maximum vectors from mlx5_comp_vectors_count() to
mlx5_comp_vectors_max().

Signed-off-by: Maher Sanalla <msanalla@nvidia.com>
Reviewed-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
2023-08-07 10:53:51 -07:00
Nicolin Chen
c157fd8861 vfio: Support IO page table replacement
Now both the physical path and the emulated path can support an IO page
table replacement. Call iommufd_device_replace/iommufd_access_replace(),
when vdev->iommufd_attached is true.

Also update the VFIO_DEVICE_ATTACH_IOMMUFD_PT kdoc in the uAPI header.

Link: https://lore.kernel.org/r/b5f01956ff161f76aa52c95b0fa1ad6eaca95c4a.1690523699.git.nicolinc@nvidia.com
Reviewed-by: Kevin Tian <kevin.tian@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>
2023-07-28 13:31:24 -03:00
Nicolin Chen
89e07fd468 vfio: Do not allow !ops->dma_unmap in vfio_pin/unpin_pages()
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>
2023-07-28 13:31:24 -03:00
Yi Liu
c1cce6d079 vfio: Compile vfio_group infrastructure optionally
vfio_group is not needed for vfio device cdev, so with vfio device cdev
introduced, the vfio_group infrastructures can be compiled out if only
cdev is needed.

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/20230718135551.6592-26-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-07-25 10:20:50 -06:00
Yi Liu
5398be2564 vfio: Move the IOMMU_CAP_CACHE_COHERENCY check in __vfio_register_dev()
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>
2023-07-25 10:20:41 -06:00
Yi Liu
b290a05fd8 vfio: Add VFIO_DEVICE_[AT|DE]TACH_IOMMUFD_PT
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>
2023-07-25 10:20:37 -06:00
Yi Liu
5fcc26969a vfio: Add VFIO_DEVICE_BIND_IOMMUFD
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>
2023-07-25 10:20:32 -06:00
Yi Liu
ca9e45b414 vfio: Avoid repeated user pointer cast in vfio_device_fops_unl_ioctl()
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>
2023-07-25 10:20:15 -06:00
Yi Liu
5c6de3ea73 vfio: Test kvm pointer in _vfio_device_get_kvm_safe()
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>
2023-07-25 10:19:45 -06:00
Yi Liu
8b6f173a4c vfio: Add cdev for vfio_device
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>
2023-07-25 10:19:40 -06:00
Yi Liu
38c24544e1 vfio: Move device_del() before waiting for the last vfio_device registration refcount
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>
2023-07-25 10:19:26 -06:00
Yi Liu
291872a533 vfio: Move vfio_device_group_unregister() to be the first operation in unregister
This avoids endless vfio_device refcount increment by userspace, which
would keep blocking the vfio_unregister_group_dev().

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/20230718135551.6592-17-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-07-25 10:19:22 -06:00
Yi Liu
8cfa718602 vfio-iommufd: Add detach_ioas support for emulated VFIO devices
This prepares for adding DETACH ioctl for emulated VFIO devices.

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/20230718135551.6592-16-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-07-25 10:19:18 -06:00
Yi Liu
9048c7341c vfio-iommufd: Add detach_ioas support for physical VFIO devices
This prepares for adding DETACH ioctl for physical VFIO devices.

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/20230718135551.6592-14-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-07-25 10:19:12 -06:00
Yi Liu
31014aef9e vfio: Record devid in vfio_device_file
.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>
2023-07-25 10:19:08 -06:00
Yi Liu
6f240ee677 vfio-iommufd: Split bind/attach into two steps
This aligns the bind/attach logic with the coming vfio device cdev support.

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/20230718135551.6592-12-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-07-25 10:19:04 -06:00
Yi Liu
6086efe734 vfio-iommufd: Move noiommu compat validation out of vfio_iommufd_bind()
This moves the noiommu compat validation logic into vfio_df_group_open().
This is more consistent with what will be done in vfio device 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/20230718135551.6592-11-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-07-25 10:19:01 -06:00
Yi Liu
839e692fa4 vfio: Make vfio_df_open() single open for device cdev path
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>
2023-07-25 10:18:57 -06:00
Yi Liu
270bf4c019 vfio: Add cdev_device_open_cnt to vfio_group
This is for counting the devices that are opened via the cdev path. This
count is increased and decreased by the cdev path. The group path checks
it to achieve exclusion with the cdev path. With this, only one path
(group path or cdev path) will claim DMA ownership. This avoids scenarios
in which devices within the same group may be opened via different paths.

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/20230718135551.6592-9-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-07-25 10:18:54 -06:00
Yi Liu
82d93f580f vfio: Block device access via device fd until device is opened
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>
2023-07-25 10:18:50 -06:00
Yi Liu
05f37e1c03 vfio: Pass struct vfio_device_file * to vfio_device_open/close()
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>
2023-07-25 10:18:47 -06:00
Yi Liu
34aeeecdb3 vfio: Accept vfio device file in the KVM facing kAPI
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>
2023-07-25 10:18:28 -06:00
Yi Liu
b1a59be8a2 vfio: Refine vfio file kAPIs for KVM
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>
2023-07-25 10:18:22 -06:00
Yi Liu
b1a3b5c61d vfio: Allocate per device file structure
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>
2023-07-25 10:18:17 -06:00
Yi Liu
71791b9246 vfio/pci: Allow passing zero-length fd array in VFIO_DEVICE_PCI_HOT_RESET
This is the way user to invoke hot-reset for the devices opened by cdev
interface. User should check the flag VFIO_PCI_HOT_RESET_FLAG_DEV_ID_OWNED
in the output of VFIO_DEVICE_GET_PCI_HOT_RESET_INFO ioctl before doing
hot-reset for cdev devices.

Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Yanting Jiang <yanting.jiang@intel.com>
Tested-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230718105542.4138-11-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-07-25 10:18:13 -06:00
Yi Liu
b56b7aabcf vfio/pci: Copy hot-reset device info to userspace in the devices loop
This copies the vfio_pci_dependent_device to userspace during looping each
affected device for reporting vfio_pci_hot_reset_info. This avoids counting
the affected devices and allocating a potential large buffer to store the
vfio_pci_dependent_device of all the affected devices before copying them
to userspace.

Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Yanting Jiang <yanting.jiang@intel.com>
Tested-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20230718105542.4138-10-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-07-25 10:18:09 -06:00
Yi Liu
9062ff405b vfio/pci: Extend VFIO_DEVICE_GET_PCI_HOT_RESET_INFO for vfio device cdev
This allows VFIO_DEVICE_GET_PCI_HOT_RESET_INFO ioctl use the iommufd_ctx
of the cdev device to check the ownership of the other affected devices.

When VFIO_DEVICE_GET_PCI_HOT_RESET_INFO is called on an IOMMUFD managed
device, the new flag VFIO_PCI_HOT_RESET_FLAG_DEV_ID is reported to indicate
the values returned are IOMMUFD devids rather than group IDs as used when
accessing vfio devices through the conventional vfio group interface.
Additionally the flag VFIO_PCI_HOT_RESET_FLAG_DEV_ID_OWNED will be reported
in this mode if all of the devices affected by the hot-reset are owned by
either virtue of being directly bound to the same iommufd context as the
calling device, or implicitly owned via a shared IOMMU group.

Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
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: Zhenzhong Duan <zhenzhong.duan@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230718105542.4138-9-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-07-25 10:18:05 -06:00
Yi Liu
a80e1de932 vfio: Add helper to search vfio_device in a dev_set
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>
2023-07-25 10:18:02 -06:00
Yi Liu
6e6c513fe1 vfio/pci: Move the existing hot reset logic to be a helper
This prepares to add another method for hot reset. The major hot reset logic
are moved to vfio_pci_ioctl_pci_hot_reset_groups().

No functional change is intended.

Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.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: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230718105542.4138-3-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-07-25 10:17:42 -06:00
Yi Liu
c60f932043 vfio/pci: Update comment around group_fd get in vfio_pci_ioctl_pci_hot_reset()
This suits more on what the code does.

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: Yanting Jiang <yanting.jiang@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Link: https://lore.kernel.org/r/20230718105542.4138-2-yi.l.liu@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-07-25 10:17:09 -06:00
Linus Torvalds
b25f62ccb4 VFIO updates for v6.5-rc1
- Adjust log levels for common messages. (Oleksandr Natalenko,
    Alex Williamson)
 
  - Support for dynamic MSI-X allocation. (Reinette Chatre)
 
  - Enable and report PCIe AtomicOp Completer capabilities.
    (Alex Williamson)
 
  - Cleanup Kconfigs for vfio bus drivers. (Alex Williamson)
 
  - Add support for CDX bus based devices. (Nipun Gupta)
 
  - Fix race with concurrent mdev initialization. (Eric Farman)
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Merge tag 'vfio-v6.5-rc1' of https://github.com/awilliam/linux-vfio

Pull VFIO updates from Alex Williamson:

 - Adjust log levels for common messages (Oleksandr Natalenko, Alex
   Williamson)

 - Support for dynamic MSI-X allocation (Reinette Chatre)

 - Enable and report PCIe AtomicOp Completer capabilities (Alex
   Williamson)

 - Cleanup Kconfigs for vfio bus drivers (Alex Williamson)

 - Add support for CDX bus based devices (Nipun Gupta)

 - Fix race with concurrent mdev initialization (Eric Farman)

* tag 'vfio-v6.5-rc1' of https://github.com/awilliam/linux-vfio:
  vfio/mdev: Move the compat_class initialization to module init
  vfio/cdx: add support for CDX bus
  vfio/fsl: Create Kconfig sub-menu
  vfio/platform: Cleanup Kconfig
  vfio/pci: Cleanup Kconfig
  vfio/pci-core: Add capability for AtomicOp completer support
  vfio/pci: Also demote hiding standard cap messages
  vfio/pci: Clear VFIO_IRQ_INFO_NORESIZE for MSI-X
  vfio/pci: Support dynamic MSI-X
  vfio/pci: Probe and store ability to support dynamic MSI-X
  vfio/pci: Use bitfield for struct vfio_pci_core_device flags
  vfio/pci: Update stale comment
  vfio/pci: Remove interrupt context counter
  vfio/pci: Use xarray for interrupt context storage
  vfio/pci: Move to single error path
  vfio/pci: Prepare for dynamic interrupt context storage
  vfio/pci: Remove negative check on unsigned vector
  vfio/pci: Consolidate irq cleanup on MSI/MSI-X disable
  vfio/pci: demote hiding ecap messages to debug level
2023-06-30 15:22:09 -07:00
Linus Torvalds
e4c8d01865 ARM: SoC drivers for 6.5
Nothing surprising in the SoC specific drivers, with the usual updates:
 
  * Added or improved SoC driver support for Tegra234, Exynos4121, RK3588,
    as well as multiple Mediatek and Qualcomm chips
 
  * SCMI firmware gains support for multiple SMC/HVC transport and version
    3.2 of the protocol
 
  * Cleanups amd minor changes for the reset controller, memory controller,
    firmware and sram drivers
 
  * Minor changes to amd/xilinx, samsung, tegra, nxp, ti, qualcomm,
    amlogic and renesas SoC specific drivers
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Merge tag 'soc-drivers-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc

Pull ARM SoC driver updates from Arnd Bergmann:
 "Nothing surprising in the SoC specific drivers, with the usual
  updates:

   - Added or improved SoC driver support for Tegra234, Exynos4121,
     RK3588, as well as multiple Mediatek and Qualcomm chips

   - SCMI firmware gains support for multiple SMC/HVC transport and
     version 3.2 of the protocol

   - Cleanups amd minor changes for the reset controller, memory
     controller, firmware and sram drivers

   - Minor changes to amd/xilinx, samsung, tegra, nxp, ti, qualcomm,
     amlogic and renesas SoC specific drivers"

* tag 'soc-drivers-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (118 commits)
  dt-bindings: interrupt-controller: Convert Amlogic Meson GPIO interrupt controller binding
  MAINTAINERS: add PHY-related files to Amlogic SoC file list
  drivers: meson: secure-pwrc: always enable DMA domain
  tee: optee: Use kmemdup() to replace kmalloc + memcpy
  soc: qcom: geni-se: Do not bother about enable/disable of interrupts in secondary sequencer
  dt-bindings: sram: qcom,imem: document qdu1000
  soc: qcom: icc-bwmon: Fix MSM8998 count unit
  dt-bindings: soc: qcom,rpmh-rsc: Require power-domains
  soc: qcom: socinfo: Add Soc ID for IPQ5300
  dt-bindings: arm: qcom,ids: add SoC ID for IPQ5300
  soc: qcom: Fix a IS_ERR() vs NULL bug in probe
  soc: qcom: socinfo: Add support for new fields in revision 19
  soc: qcom: socinfo: Add support for new fields in revision 18
  dt-bindings: firmware: scm: Add compatible for SDX75
  soc: qcom: mdt_loader: Fix split image detection
  dt-bindings: memory-controllers: drop unneeded quotes
  soc: rockchip: dtpm: use C99 array init syntax
  firmware: tegra: bpmp: Add support for DRAM MRQ GSCs
  soc/tegra: pmc: Use devm_clk_notifier_register()
  soc/tegra: pmc: Simplify debugfs initialization
  ...
2023-06-29 15:22:19 -07:00
Eric Farman
ff598081e5 vfio/mdev: Move the compat_class initialization to module init
The pointer to mdev_bus_compat_class is statically defined at the top
of mdev_core, and was originally (commit 7b96953bc6 ("vfio: Mediated
device Core driver") serialized by the parent_list_lock. The blamed
commit removed this mutex, leaving the pointer initialization
unserialized. As a result, the creation of multiple MDEVs in parallel
(such as during boot) can encounter errors during the creation of the
sysfs entries, such as:

  [    8.337509] sysfs: cannot create duplicate filename '/class/mdev_bus'
  [    8.337514] vfio_ccw 0.0.01d8: MDEV: Registered
  [    8.337516] CPU: 13 PID: 946 Comm: driverctl Not tainted 6.4.0-rc7 #20
  [    8.337522] Hardware name: IBM 3906 M05 780 (LPAR)
  [    8.337525] Call Trace:
  [    8.337528]  [<0000000162b0145a>] dump_stack_lvl+0x62/0x80
  [    8.337540]  [<00000001622aeb30>] sysfs_warn_dup+0x78/0x88
  [    8.337549]  [<00000001622aeca6>] sysfs_create_dir_ns+0xe6/0xf8
  [    8.337552]  [<0000000162b04504>] kobject_add_internal+0xf4/0x340
  [    8.337557]  [<0000000162b04d48>] kobject_add+0x78/0xd0
  [    8.337561]  [<0000000162b04e0a>] kobject_create_and_add+0x6a/0xb8
  [    8.337565]  [<00000001627a110e>] class_compat_register+0x5e/0x90
  [    8.337572]  [<000003ff7fd815da>] mdev_register_parent+0x102/0x130 [mdev]
  [    8.337581]  [<000003ff7fdc7f2c>] vfio_ccw_sch_probe+0xe4/0x178 [vfio_ccw]
  [    8.337588]  [<0000000162a7833c>] css_probe+0x44/0x80
  [    8.337599]  [<000000016279f4da>] really_probe+0xd2/0x460
  [    8.337603]  [<000000016279fa08>] driver_probe_device+0x40/0xf0
  [    8.337606]  [<000000016279fb78>] __device_attach_driver+0xc0/0x140
  [    8.337610]  [<000000016279cbe0>] bus_for_each_drv+0x90/0xd8
  [    8.337618]  [<00000001627a00b0>] __device_attach+0x110/0x190
  [    8.337621]  [<000000016279c7c8>] bus_rescan_devices_helper+0x60/0xb0
  [    8.337626]  [<000000016279cd48>] drivers_probe_store+0x48/0x80
  [    8.337632]  [<00000001622ac9b0>] kernfs_fop_write_iter+0x138/0x1f0
  [    8.337635]  [<00000001621e5e14>] vfs_write+0x1ac/0x2f8
  [    8.337645]  [<00000001621e61d8>] ksys_write+0x70/0x100
  [    8.337650]  [<0000000162b2bdc4>] __do_syscall+0x1d4/0x200
  [    8.337656]  [<0000000162b3c828>] system_call+0x70/0x98
  [    8.337664] kobject: kobject_add_internal failed for mdev_bus with -EEXIST, don't try to register things with the same name in the same directory.
  [    8.337668] kobject: kobject_create_and_add: kobject_add error: -17
  [    8.337674] vfio_ccw: probe of 0.0.01d9 failed with error -12
  [    8.342941] vfio_ccw_mdev aeb9ca91-10c6-42bc-a168-320023570aea: Adding to iommu group 2

Move the initialization of the mdev_bus_compat_class pointer to the
init path, to match the cleanup in module exit. This way the code
in mdev_register_parent() can simply link the new parent to it,
rather than determining whether initialization is required first.

Fixes: 89345d5177 ("vfio/mdev: embedd struct mdev_parent in the parent data structure")
Reported-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20230626133642.2939168-1-farman@linux.ibm.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2023-06-27 12:05:26 -06:00
Ryan Roberts
c33c794828 mm: ptep_get() conversion
Convert all instances of direct pte_t* dereferencing to instead use
ptep_get() helper.  This means that by default, the accesses change from a
C dereference to a READ_ONCE().  This is technically the correct thing to
do since where pgtables are modified by HW (for access/dirty) they are
volatile and therefore we should always ensure READ_ONCE() semantics.

But more importantly, by always using the helper, it can be overridden by
the architecture to fully encapsulate the contents of the pte.  Arch code
is deliberately not converted, as the arch code knows best.  It is
intended that arch code (arm64) will override the default with its own
implementation that can (e.g.) hide certain bits from the core code, or
determine young/dirty status by mixing in state from another source.

Conversion was done using Coccinelle:

----

// $ make coccicheck \
//          COCCI=ptepget.cocci \
//          SPFLAGS="--include-headers" \
//          MODE=patch

virtual patch

@ depends on patch @
pte_t *v;
@@

- *v
+ ptep_get(v)

----

Then reviewed and hand-edited to avoid multiple unnecessary calls to
ptep_get(), instead opting to store the result of a single call in a
variable, where it is correct to do so.  This aims to negate any cost of
READ_ONCE() and will benefit arch-overrides that may be more complex.

Included is a fix for an issue in an earlier version of this patch that
was pointed out by kernel test robot.  The issue arose because config
MMU=n elides definition of the ptep helper functions, including
ptep_get().  HUGETLB_PAGE=n configs still define a simple
huge_ptep_clear_flush() for linking purposes, which dereferences the ptep.
So when both configs are disabled, this caused a build error because
ptep_get() is not defined.  Fix by continuing to do a direct dereference
when MMU=n.  This is safe because for this config the arch code cannot be
trying to virtualize the ptes because none of the ptep helpers are
defined.

Link: https://lkml.kernel.org/r/20230612151545.3317766-4-ryan.roberts@arm.com
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/oe-kbuild-all/202305120142.yXsNEo6H-lkp@intel.com/
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Dave Airlie <airlied@gmail.com>
Cc: Dimitri Sivanich <dimitri.sivanich@hpe.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: SeongJae Park <sj@kernel.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-19 16:19:25 -07:00