[RFC PATCH v3 0/4] kvmppc: HMM backend driver to manage pages of secure guest

[Bharata B Rao]

Hi,

A pseries guest can be run as a secure guest on Ultravisor-enabled
POWER platforms. On such platforms, this driver will be used to manage
the movement of guest pages between the normal memory managed by
hypervisor (HV) and secure memory managed by Ultravisor (UV).

Private ZONE_DEVICE memory equal to the amount of secure memory
available in the platform for running secure guests is created
via a HMM device. The movement of pages between normal and secure
memory is done by ->alloc_and_copy() callback routine of migrate_vma().

The page-in or page-out requests from UV will come to HV as hcalls and
HV will call back into UV via uvcalls to satisfy these page requests.

These patches apply and work on the base Ultravisor patches posted by
Ram Pai at https://www.spinics.net/lists/kvm-ppc/msg14981.html

Changes in v3
=============
- Rebased to latest kernel
- Rebased on top of Ram's base Ultravisor patches, so that all the
  dependencies are met.
- Get secure memory size from device tree.
- Fix a mm struct leak in page-in and page-out hcalls, thereby
  allowing LPID recycling (Thanks to Sukadev Bhattiprolu for pointing
  this out)

v2: https://lists.ozlabs.org/pipermail/linuxppc-dev/2018-November/181669.html

Bharata B Rao (4):
  kvmppc: HMM backend driver to manage pages of secure guest
  kvmppc: Add support for shared pages in HMM driver
  kvmppc: H_SVM_INIT_START and H_SVM_INIT_DONE hcalls
  kvmppc: Handle memory plug/unplug to secure VM

 arch/powerpc/include/asm/hvcall.h           |   9 +
 arch/powerpc/include/asm/kvm_book3s_hmm.h   |  45 ++
 arch/powerpc/include/asm/kvm_host.h         |  14 +
 arch/powerpc/include/asm/ucall-api.h        |  35 ++
 arch/powerpc/include/uapi/asm/uapi_uvcall.h |   5 +
 arch/powerpc/kvm/Makefile                   |   3 +
 arch/powerpc/kvm/book3s_hv.c                |  48 ++
 arch/powerpc/kvm/book3s_hv_hmm.c            | 559 ++++++++++++++++++++
 8 files changed, 718 insertions(+)
 create mode 100644 arch/powerpc/include/asm/kvm_book3s_hmm.h
 create mode 100644 arch/powerpc/kvm/book3s_hv_hmm.c

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2.17.1