[PATCH v9 0/8] KVM: PPC: Driver to manage pages of secure guest

[Bharata B Rao <bharata@linux.ibm.com>]

[The main change in this version is the introduction of new
locking to prevent concurrent page-in and page-out calls. More
details about this are present in patch 2/8]

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.
Whenever a page belonging to the guest becomes secure, a page from
this private device memory is used to represent and track that secure
page on the HV side. The movement of pages between normal and secure
memory is done via migrate_vma_pages(). The reverse movement is driven
via pagemap_ops.migrate_to_ram().

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 are against hmm.git
(https://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma.git/log/?h=hmm)

plus

Claudio Carvalho's base ultravisor enablement patches that are present
in Michael Ellerman's tree
(https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/log/?h=topic/ppc-kvm)

These patches along with Claudio's above patches are required to
run secure pseries guests on KVM. This patchset is based on hmm.git
because hmm.git has migrate_vma cleanup and not-device memremap_pages
patchsets that are required by this patchset.

Changes in v9
=============
- Prevent concurrent page-in and page-out calls.
- Ensure device PFNs are allocated for zero-pages that are sent to UV.
- Failure to migrate a page during page-in will now return error via
  hcall.
- Address review comments by Suka
- Misc cleanups

v8: https://lore.kernel.org/linux-mm/20190910082946.7849-2-bharata@linux.ibm.com/T/

Anshuman Khandual (1):
  KVM: PPC: Ultravisor: Add PPC_UV config option

Bharata B Rao (6):
  KVM: PPC: Move pages between normal and secure memory
  KVM: PPC: Shared pages support for secure guests
  KVM: PPC: H_SVM_INIT_START and H_SVM_INIT_DONE hcalls
  KVM: PPC: Handle memory plug/unplug to secure VM
  KVM: PPC: Radix changes for secure guest
  KVM: PPC: Support reset of secure guest

Suraj Jitindar Singh (1):
  KVM: PPC: Book3S HV: Define usage types for rmap array in guest
    memslot

 Documentation/virt/kvm/api.txt              |  19 +
 arch/powerpc/Kconfig                        |  17 +
 arch/powerpc/include/asm/hvcall.h           |   9 +
 arch/powerpc/include/asm/kvm_book3s_uvmem.h |  48 ++
 arch/powerpc/include/asm/kvm_host.h         |  57 +-
 arch/powerpc/include/asm/kvm_ppc.h          |   2 +
 arch/powerpc/include/asm/ultravisor-api.h   |   6 +
 arch/powerpc/include/asm/ultravisor.h       |  36 ++
 arch/powerpc/kvm/Makefile                   |   3 +
 arch/powerpc/kvm/book3s_64_mmu_radix.c      |  22 +
 arch/powerpc/kvm/book3s_hv.c                | 122 ++++
 arch/powerpc/kvm/book3s_hv_rm_mmu.c         |   2 +-
 arch/powerpc/kvm/book3s_hv_uvmem.c          | 673 ++++++++++++++++++++
 arch/powerpc/kvm/powerpc.c                  |  12 +
 include/uapi/linux/kvm.h                    |   1 +
 15 files changed, 1024 insertions(+), 5 deletions(-)
 create mode 100644 arch/powerpc/include/asm/kvm_book3s_uvmem.h
 create mode 100644 arch/powerpc/kvm/book3s_hv_uvmem.c

-- 
2.21.0