[PATCH v2 00/19] Microsoft Hypervisor root partition ioctl interface

From: Nuno Das Neves
Date: Thu Aug 05 2021 - 17:24:53 EST


This patch series provides a userspace interface for creating and running guest
virtual machines while running on the Microsoft Hypervisor [0].

Since managing guest machines can only be done when Linux is the root partition,
this series depends on Wei Liu's patch series merged in 5.12:
https://lore.kernel.org/linux-hyperv/20210203150435.27941-1-wei.liu@xxxxxxxxxx/

The first two patches provide some helpers for converting hypervisor status
codes to linux error codes, and printing hypervisor status codes to dmesg for
debugging.

Hyper-V related headers asm-generic/hyperv-tlfs.h and x86/asm/hyperv-tlfs.h are
split into uapi and non-uapi. The uapi versions contain structures used in both
the ioctl interface and the kernel.

The mshv API is introduced in drivers/hv/mshv_main.c. As each interface is
introduced, documentation is added in Documentation/virt/mshv/api.rst.
The API is file-desciptor based, like KVM. The entry point is /dev/mshv.

/dev/mshv ioctls:
MSHV_CHECK_EXTENSION
MSHV_CREATE_PARTITION

Partition (vm) ioctls:
MSHV_MAP_GUEST_MEMORY, MSHV_UNMAP_GUEST_MEMORY
MSHV_INSTALL_INTERCEPT
MSHV_ASSERT_INTERRUPT
MSHV_GET_PARTITION_PROPERTY, MSHV_SET_PARTITION_PROPERTY
MSHV_CREATE_VP

Vp (vcpu) ioctls:
MSHV_GET_VP_REGISTERS, MSHV_SET_VP_REGISTERS
MSHV_RUN_VP
MSHV_GET_VP_STATE, MSHV_SET_VP_STATE
MSHV_VP_TRANSLATE_GVA
mmap() (register page)

[0] Hyper-V is more well-known, but it really refers to the whole stack
including the hypervisor and other components that run in Windows kernel
and userspace.

Changes since v1:
1. Correct mshv_dev mode to octal 0600
2. Fix bug in mshv_vp_iotcl_run - correctly set suspend registers on early exit
3. Fix bug in translate gva patch, provided by Anatol Belski
4. Address comments from Wei Liu, Sunil Muthuswamy, and Vitaly Kuznetsov
5. Run checkpatch.pl - fix whitespace and other style issues

Changes since RFC:
1. Moved code from virt/mshv to drivers/hv
2. Split hypercall helper functions and synic code to hv_call.c and hv_synic.c
3. MSHV_REQUEST_VERSION ioctl replaced with MSHV_CHECK_EXTENSION
3. Numerous suggestions, fixes, style changes, etc from Michael Kelley, Vitaly
Kuznetsov, Wei Liu, and Vineeth Pillai
4. Added patch to enable hypervisor enlightenments on partition creation
5. Added Wei Liu's patch for GVA to GPA translation

Nuno Das Neves (18):
x86/hyperv: convert hyperv statuses to linux error codes
x86/hyperv: convert hyperv statuses to strings
drivers/hv: minimal mshv module (/dev/mshv/)
drivers/hv: check extension ioctl
drivers/hv: create partition ioctl
drivers/hv: create, initialize, finalize, delete partition hypercalls
drivers/hv: withdraw memory hypercall
drivers/hv: map and unmap guest memory
drivers/hv: create vcpu ioctl
drivers/hv: get and set vcpu registers ioctls
drivers/hv: set up synic pages for intercept messages
drivers/hv: run vp ioctl and isr
drivers/hv: install intercept ioctl
drivers/hv: assert interrupt ioctl
drivers/hv: get and set vp state ioctls
drivers/hv: mmap vp register page
drivers/hv: get and set partition property ioctls
drivers/hv: Add enlightenment bits to create partition ioctl

Wei Liu (1):
drivers/hv: Translate GVA to GPA

.../userspace-api/ioctl/ioctl-number.rst | 2 +
Documentation/virt/mshv/api.rst | 173 +++
arch/x86/hyperv/Makefile | 1 +
arch/x86/hyperv/hv_init.c | 2 +-
arch/x86/hyperv/hv_proc.c | 51 +-
arch/x86/include/asm/hyperv-tlfs.h | 15 +-
arch/x86/include/asm/mshyperv.h | 1 +
arch/x86/include/uapi/asm/hyperv-tlfs.h | 1274 +++++++++++++++++
arch/x86/kernel/cpu/mshyperv.c | 16 +
drivers/hv/Kconfig | 18 +
drivers/hv/Makefile | 3 +
drivers/hv/hv_call.c | 742 ++++++++++
drivers/hv/hv_synic.c | 181 +++
drivers/hv/mshv.h | 120 ++
drivers/hv/mshv_main.c | 1166 +++++++++++++++
include/asm-generic/hyperv-tlfs.h | 354 +++--
include/asm-generic/mshyperv.h | 4 +
include/linux/mshv.h | 61 +
include/uapi/asm-generic/hyperv-tlfs.h | 242 ++++
include/uapi/linux/mshv.h | 117 ++
20 files changed, 4398 insertions(+), 145 deletions(-)
create mode 100644 Documentation/virt/mshv/api.rst
create mode 100644 arch/x86/include/uapi/asm/hyperv-tlfs.h
create mode 100644 drivers/hv/hv_call.c
create mode 100644 drivers/hv/hv_synic.c
create mode 100644 drivers/hv/mshv.h
create mode 100644 drivers/hv/mshv_main.c
create mode 100644 include/linux/mshv.h
create mode 100644 include/uapi/asm-generic/hyperv-tlfs.h
create mode 100644 include/uapi/linux/mshv.h

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2.23.4