Commit Graph

6 Commits

Author SHA1 Message Date
Paul Mackerras 70cd4c10b2 KVM: PPC: Book3S HV: Fix software walk of guest process page tables
This fixes some bugs in the code that walks the guest's page tables.
These bugs cause MMIO emulation to fail whenever the guest is in
virtial mode (MMU on), leading to the guest hanging if it tried to
access a virtio device.

The first bug was that when reading the guest's process table, we were
using the whole of arch->process_table, not just the field that contains
the process table base address.  The second bug was that the mask used
when reading the process table entry to get the radix tree base address,
RPDB_MASK, had the wrong value.

Fixes: 9e04ba69be ("KVM: PPC: Book3S HV: Add basic infrastructure for radix guests")
Fixes: e99833448c ("powerpc/mm/radix: Add partition table format & callback")
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-03-01 11:53:45 +11:00
Paul Mackerras 8cf4ecc0ca KVM: PPC: Book3S HV: Enable radix guest support
This adds a few last pieces of the support for radix guests:

* Implement the backends for the KVM_PPC_CONFIGURE_V3_MMU and
  KVM_PPC_GET_RMMU_INFO ioctls for radix guests

* On POWER9, allow secondary threads to be on/off-lined while guests
  are running.

* Set up LPCR and the partition table entry for radix guests.

* Don't allocate the rmap array in the kvm_memory_slot structure
  on radix.

* Don't try to initialize the HPT for radix guests, since they don't
  have an HPT.

* Take out the code that prevents the HV KVM module from
  initializing on radix hosts.

At this stage, we only support radix guests if the host is running
in radix mode, and only support HPT guests if the host is running in
HPT mode.  Thus a guest cannot switch from one mode to the other,
which enables some simplifications.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 19:11:52 +11:00
Paul Mackerras 8f7b79b837 KVM: PPC: Book3S HV: Implement dirty page logging for radix guests
This adds code to keep track of dirty pages when requested (that is,
when memslot->dirty_bitmap is non-NULL) for radix guests.  We use the
dirty bits in the PTEs in the second-level (partition-scoped) page
tables, together with a bitmap of pages that were dirty when their
PTE was invalidated (e.g., when the page was paged out).  This bitmap
is stored in the first half of the memslot->dirty_bitmap area, and
kvm_vm_ioctl_get_dirty_log_hv() now uses the second half for the
bitmap that gets returned to userspace.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 19:11:50 +11:00
Paul Mackerras 01756099e0 KVM: PPC: Book3S HV: MMU notifier callbacks for radix guests
This adapts our implementations of the MMU notifier callbacks
(unmap_hva, unmap_hva_range, age_hva, test_age_hva, set_spte_hva)
to call radix functions when the guest is using radix.  These
implementations are much simpler than for HPT guests because we
have only one PTE to deal with, so we don't need to traverse
rmap chains.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 19:11:49 +11:00
Paul Mackerras 5a319350a4 KVM: PPC: Book3S HV: Page table construction and page faults for radix guests
This adds the code to construct the second-level ("partition-scoped" in
architecturese) page tables for guests using the radix MMU.  Apart from
the PGD level, which is allocated when the guest is created, the rest
of the tree is all constructed in response to hypervisor page faults.

As well as hypervisor page faults for missing pages, we also get faults
for reference/change (RC) bits needing to be set, as well as various
other error conditions.  For now, we only set the R or C bit in the
guest page table if the same bit is set in the host PTE for the
backing page.

This code can take advantage of the guest being backed with either
transparent or ordinary 2MB huge pages, and insert 2MB page entries
into the guest page tables.  There is no support for 1GB huge pages
yet.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 19:11:49 +11:00
Paul Mackerras 9e04ba69be KVM: PPC: Book3S HV: Add basic infrastructure for radix guests
This adds a field in struct kvm_arch and an inline helper to
indicate whether a guest is a radix guest or not, plus a new file
to contain the radix MMU code, which currently contains just a
translate function which knows how to traverse the guest page
tables to translate an address.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 19:11:48 +11:00