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Linus Torvalds 08cdc21579 iommufd for 6.2 
iommufd is the user API to control the IOMMU subsystem as it relates to
 managing IO page tables that point at user space memory.
 
 It takes over from drivers/vfio/vfio_iommu_type1.c (aka the VFIO
 container) which is the VFIO specific interface for a similar idea.
 
 We see a broad need for extended features, some being highly IOMMU device
 specific:
  - Binding iommu_domain's to PASID/SSID
  - Userspace IO page tables, for ARM, x86 and S390
  - Kernel bypassed invalidation of user page tables
  - Re-use of the KVM page table in the IOMMU
  - Dirty page tracking in the IOMMU
  - Runtime Increase/Decrease of IOPTE size
  - PRI support with faults resolved in userspace
 
 Many of these HW features exist to support VM use cases - for instance the
 combination of PASID, PRI and Userspace IO Page Tables allows an
 implementation of DMA Shared Virtual Addressing (vSVA) within a
 guest. Dirty tracking enables VM live migration with SRIOV devices and
 PASID support allow creating "scalable IOV" devices, among other things.
 
 As these features are fundamental to a VM platform they need to be
 uniformly exposed to all the driver families that do DMA into VMs, which
 is currently VFIO and VDPA.
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Merge tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd

Pull iommufd implementation from Jason Gunthorpe:
 "iommufd is the user API to control the IOMMU subsystem as it relates
  to managing IO page tables that point at user space memory.

  It takes over from drivers/vfio/vfio_iommu_type1.c (aka the VFIO
  container) which is the VFIO specific interface for a similar idea.

  We see a broad need for extended features, some being highly IOMMU
  device specific:
   - Binding iommu_domain's to PASID/SSID
   - Userspace IO page tables, for ARM, x86 and S390
   - Kernel bypassed invalidation of user page tables
   - Re-use of the KVM page table in the IOMMU
   - Dirty page tracking in the IOMMU
   - Runtime Increase/Decrease of IOPTE size
   - PRI support with faults resolved in userspace

  Many of these HW features exist to support VM use cases - for instance
  the combination of PASID, PRI and Userspace IO Page Tables allows an
  implementation of DMA Shared Virtual Addressing (vSVA) within a guest.
  Dirty tracking enables VM live migration with SRIOV devices and PASID
  support allow creating "scalable IOV" devices, among other things.

  As these features are fundamental to a VM platform they need to be
  uniformly exposed to all the driver families that do DMA into VMs,
  which is currently VFIO and VDPA"

For more background, see the extended explanations in Jason's pull request:

  https://lore.kernel.org/lkml/Y5dzTU8dlmXTbzoJ@nvidia.com/

* tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd: (62 commits)
  iommufd: Change the order of MSI setup
  iommufd: Improve a few unclear bits of code
  iommufd: Fix comment typos
  vfio: Move vfio group specific code into group.c
  vfio: Refactor dma APIs for emulated devices
  vfio: Wrap vfio group module init/clean code into helpers
  vfio: Refactor vfio_device open and close
  vfio: Make vfio_device_open() truly device specific
  vfio: Swap order of vfio_device_container_register() and open_device()
  vfio: Set device->group in helper function
  vfio: Create wrappers for group register/unregister
  vfio: Move the sanity check of the group to vfio_create_group()
  vfio: Simplify vfio_create_group()
  iommufd: Allow iommufd to supply /dev/vfio/vfio
  vfio: Make vfio_container optionally compiled
  vfio: Move container related MODULE_ALIAS statements into container.c
  vfio-iommufd: Support iommufd for emulated VFIO devices
  vfio-iommufd: Support iommufd for physical VFIO devices
  vfio-iommufd: Allow iommufd to be used in place of a container fd
  vfio: Use IOMMU_CAP_ENFORCE_CACHE_COHERENCY for vfio_file_enforced_coherent()
  ...
2022-12-14 09:15:43 -08:00
..
accelerators Documentation: ocxl.rst: change FPGA indirect article to an 2021-06-09 14:51:25 +02:00
ebpf docs/bpf: Add bpf() syscall command reference 2021-03-04 18:39:46 -08:00
ioctl iommufd: File descriptor, context, kconfig and makefiles 2022-11-30 20:16:49 -04:00
media media updates for v6.2-rc1 2022-12-13 11:36:58 -08:00
netlink docs: netlink: clarify the historical baggage of Netlink flags 2022-09-29 18:39:39 -07:00
futex2.rst futex2: Documentation: Document sys_futex_waitv() uAPI 2021-10-07 13:51:13 +02:00
index.rst iommufd: Document overview of iommufd 2022-11-30 20:16:49 -04:00
iommu.rst docs: IOMMU user API 2020-10-01 14:52:46 +02:00
iommufd.rst iommufd: Document overview of iommufd 2022-11-30 20:16:49 -04:00
landlock.rst landlock: Document Landlock's file truncation support 2022-10-19 09:01:48 +02:00
no_new_privs.rst
seccomp_filter.rst seccomp: Add wait_killable semantic to seccomp user notifier 2022-05-03 14:11:58 -07:00
spec_ctrl.rst Documentation: Add L1D flushing Documentation 2021-07-28 11:42:25 +02:00
sysfs-platform_profile.rst Documentation: Add documentation for new platform_profile sysfs attribute 2020-12-30 18:28:57 +01:00
unshare.rst
vduse.rst VDUSE: fix documentation underline warning 2021-10-13 08:42:07 -04:00