Re: [Qemu-devel] [PATCH qemu v16 00/19] spapr: vfio: Enable Dynamic DMA windows (DDW)

From: Alex Williamson <alex.williamson@redhat.com>
To: Alexey Kardashevskiy <aik@ozlabs.ru>
Cc: Paolo Bonzini <pbonzini@redhat.com>,
	David Gibson <david@gibson.dropbear.id.au>,
	qemu-ppc@nongnu.org, qemu-devel@nongnu.org,
	Alexander Graf <agraf@suse.de>
Subject: Re: [Qemu-devel] [PATCH qemu v16 00/19] spapr: vfio: Enable Dynamic DMA windows (DDW)
Date: Thu, 12 May 2016 23:36:00 -0600	[thread overview]
Message-ID: <20160512233600.2d4a0a0f@t450s.home> (raw)
In-Reply-To: <f855197a-069c-457d-e1bc-d942ef5d0cdb@ozlabs.ru>

On Fri, 13 May 2016 14:54:52 +1000
Alexey Kardashevskiy <aik@ozlabs.ru> wrote:

> Alex W,
> 
> could you please review VFIO-related chunks? Thanks!


https://lists.nongnu.org/archive/html/qemu-devel/2016-05/msg00744.html
https://lists.nongnu.org/archive/html/qemu-devel/2016-05/msg00745.html


> On 05/04/2016 04:52 PM, Alexey Kardashevskiy wrote:
> > Each Partitionable Endpoint (IOMMU group) has an address range on a PCI bus
> > where devices are allowed to do DMA. These ranges are called DMA windows.
> > By default, there is a single DMA window, 1 or 2GB big, mapped at zero
> > on a PCI bus.
> >
> > PAPR defines a DDW RTAS API which allows pseries guests
> > querying the hypervisor about DDW support and capabilities (page size mask
> > for now). A pseries guest may request an additional (to the default)
> > DMA windows using this RTAS API.
> > The existing pseries Linux guests request an additional window as big as
> > the guest RAM and map the entire guest window which effectively creates
> > direct mapping of the guest memory to a PCI bus.
> >
> > This patchset reworks PPC64 IOMMU code and adds necessary structures
> > to support big windows on pseries.
> >
> > This patchset is based on the latest upstream.
> >
> > This includes "vmstate: Define VARRAY with VMS_ALLOC" as it has been accepted
> > but has not been merged to upstream yet.
> >
> > Please comment. Thanks!
> >
> >
> > Paolo, I did cc: you on this because of 02/19 and 03/19, would be great to
> > get an opinion as the rest of the series relies on it to do
> > vfio-pci hot _un_plug properly. Thanks!
> >
> >
> > Alexey Kardashevskiy (19):
> >   vfio: Delay DMA address space listener release
> >   memory: Call region_del() callbacks on memory listener unregistering
> >   memory: Fix IOMMU replay base address
> >   vmstate: Define VARRAY with VMS_ALLOC
> >   vfio: Check that IOMMU MR translates to system address space
> >   spapr_pci: Use correct DMA LIOBN when composing the device tree
> >   spapr_iommu: Move table allocation to helpers
> >   spapr_iommu: Introduce "enabled" state for TCE table
> >   spapr_iommu: Finish renaming vfio_accel to need_vfio
> >   spapr_iommu: Migrate full state
> >   spapr_iommu: Add root memory region
> >   spapr_pci: Reset DMA config on PHB reset
> >   memory: Add reporting of supported page sizes
> >   vfio: spapr: Add DMA memory preregistering (SPAPR IOMMU v2)
> >   spapr_pci: Add and export DMA resetting helper
> >   vfio: Add host side DMA window capabilities
> >   spapr_iommu, vfio, memory: Notify IOMMU about starting/stopping being
> >     used by VFIO
> >   vfio/spapr: Create DMA window dynamically (SPAPR IOMMU v2)
> >   spapr_pci/spapr_pci_vfio: Support Dynamic DMA Windows (DDW)
> >
> >  hw/ppc/Makefile.objs          |   1 +
> >  hw/ppc/spapr.c                |   5 +
> >  hw/ppc/spapr_iommu.c          | 228 ++++++++++++++++++++++++------
> >  hw/ppc/spapr_pci.c            |  96 +++++++++----
> >  hw/ppc/spapr_rtas_ddw.c       | 292 ++++++++++++++++++++++++++++++++++++++
> >  hw/ppc/spapr_vio.c            |   8 +-
> >  hw/vfio/Makefile.objs         |   1 +
> >  hw/vfio/common.c              | 319 +++++++++++++++++++++++++++++++++++-------
> >  hw/vfio/prereg.c              | 137 ++++++++++++++++++
> >  include/exec/memory.h         |  22 ++-
> >  include/hw/pci-host/spapr.h   |  10 +-
> >  include/hw/ppc/spapr.h        |  31 +++-
> >  include/hw/vfio/vfio-common.h |  21 ++-
> >  include/migration/vmstate.h   |  10 ++
> >  memory.c                      |  64 ++++++++-
> >  target-ppc/kvm_ppc.h          |   2 +-
> >  trace-events                  |  12 +-
> >  17 files changed, 1120 insertions(+), 139 deletions(-)
> >  create mode 100644 hw/ppc/spapr_rtas_ddw.c
> >  create mode 100644 hw/vfio/prereg.c
> >  
> 
>