Both platform and PCI vfio drivers create a "slow", I/O memory region
with one or more mmap memory regions overlayed when supported by the
device. Generalize this to a set of common helpers in the core that
pulls the region info from vfio, fills the region data, configures
slow mapping, and adds helpers for comleting the mmap, enable/disable,
and teardown. This can be immediately used by the PCI MSI-X code,
which needs to mmap around the MSI-X vector table.
This also changes VFIORegion.mem to be dynamically allocated because
otherwise we don't know how the caller has allocated VFIORegion and
therefore don't know whether to unreference it to destroy the
MemoryRegion or not.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
In preparation for supporting capability chains on regions, wrap
ioctl(VFIO_DEVICE_GET_REGION_INFO) so we don't duplicate the code for
each caller.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio-pci currently requires a host= parameter, which comes in the
form of a PCI address in [domain:]<bus:slot.function> notation. We
expect to find a matching entry in sysfs for that under
/sys/bus/pci/devices/. vfio-platform takes a similar approach, but
defines the host= parameter to be a string, which can be matched
directly under /sys/bus/platform/devices/. On the PCI side, we have
some interest in using vfio to expose vGPU devices. These are not
actual discrete PCI devices, so they don't have a compatible host PCI
bus address or a device link where QEMU wants to look for it. There's
also really no requirement that vfio can only be used to expose
physical devices, a new vfio bus and iommu driver could expose a
completely emulated device. To fit within the vfio framework, it
would need a kernel struct device and associated IOMMU group, but
those are easy constraints to manage.
To support such devices, which would include vGPUs, that honor the
VFIO PCI programming API, but are not necessarily backed by a unique
PCI address, add support for specifying any device in sysfs. The
vfio API already has support for probing the device type to ensure
compatibility with either vfio-pci or vfio-platform.
With this, a vfio-pci device could either be specified as:
-device vfio-pci,host=02:00.0
or
-device vfio-pci,sysfsdev=/sys/devices/pci0000:00/0000:00:1c.0/0000:02:00.0
or even
-device vfio-pci,sysfsdev=/sys/bus/pci/devices/0000:02:00.0
When vGPU support comes along, this might look something more like:
-device vfio-pci,sysfsdev=/sys/devices/virtual/intel-vgpu/vgpu0@0000:00:02.0
NB - This is only a made up example path
The same change is made for vfio-platform, specifying sysfsdev has
precedence over the old host option.
Tested-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This patch introduces the amd-xgbe VFIO platform device. It
allows the guest to do passthrough on a device exposing an
"amd,xgbe-seattle-v1a" compat string.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Depending on the host IOMMU type we determine and record the available page
sizes for IOMMU translation. We'll need this for other validation in
future patches.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The current vfio core code assumes that the host IOMMU is capable of
mapping any IOVA the guest wants to use to where we need. However, real
IOMMUs generally only support translating a certain range of IOVAs (the
"DMA window") not a full 64-bit address space.
The common x86 IOMMUs support a wide enough range that guests are very
unlikely to go beyond it in practice, however the IOMMU used on IBM Power
machines - in the default configuration - supports only a much more limited
IOVA range, usually 0..2GiB.
If the guest attempts to set up an IOVA range that the host IOMMU can't
map, qemu won't report an error until it actually attempts to map a bad
IOVA. If guest RAM is being mapped directly into the IOMMU (i.e. no guest
visible IOMMU) then this will show up very quickly. If there is a guest
visible IOMMU, however, the problem might not show up until much later when
the guest actually attempt to DMA with an IOVA the host can't handle.
This patch adds a test so that we will detect earlier if the guest is
attempting to use IOVA ranges that the host IOMMU won't be able to deal
with.
For now, we assume that "Type1" (x86) IOMMUs can support any IOVA, this is
incorrect, but no worse than what we have already. We can't do better for
now because the Type1 kernel interface doesn't tell us what IOVA range the
IOMMU actually supports.
For the Power "sPAPR TCE" IOMMU, however, we can retrieve the supported
IOVA range and validate guest IOVA ranges against it, and this patch does
so.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Currently the VFIOContainer iommu_data field contains a union with
different information for different host iommu types. However:
* It only actually contains information for the x86-like "Type1" iommu
* Because we have a common listener the Type1 fields are actually used
on all IOMMU types, including the SPAPR TCE type as well
In fact we now have a general structure for the listener which is unlikely
to ever need per-iommu-type information, so this patch removes the union.
In a similar way we can unify the setup of the vfio memory listener in
vfio_connect_container() that is currently split across a switch on iommu
type, but is effectively the same in both cases.
The iommu_data.release pointer was only needed as a cleanup function
which would handle potentially different data in the union. With the
union gone, it too can be removed.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
unmask EventNotifier might not be initialized in case of edge
sensitive irq. Using EventNotifier pointers make life simpler to
handle the edge-sensitive irqfd setup.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The default should be to allow mmap and new drivers shouldn't need to
expose an option or set it to other than the allocation default in
their initfn. Take advantage of the experimental flag to change this
option to the correct polarity.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Tracing is more effective when we can completely disable all KVM
bypass paths. Make these runtime rather than build-time configurable.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This patch aims at optimizing IRQ handling using irqfd framework.
Instead of handling the eventfds on user-side they are handled on
kernel side using
- the KVM irqfd framework,
- the VFIO driver virqfd framework.
the virtual IRQ completion is trapped at interrupt controller
This removes the need for fast/slow path swap.
Overall this brings significant performance improvements.
Signed-off-by: Alvise Rigo <a.rigo@virtualopensystems.com>
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Vikram Sethi <vikrams@codeaurora.org>
Acked-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The platform device class has become abstract. This patch introduces
a calxeda xgmac device that derives from it.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This patch adds the code requested to assign interrupts to
a guest. The interrupts are mediated through user handled
eventfds only.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Vikram Sethi <vikrams@codeaurora.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Minimal VFIO platform implementation supporting register space
user mapping but not IRQ assignment.
Signed-off-by: Kim Phillips <kim.phillips@linaro.org>
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Vikram Sethi <vikrams@codeaurora.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Disabling MMAP support uses the slower read/write accesses but allows to
trace all MMIO accesses, which is not good for performance, but very
useful for reverse engineering PCI drivers. This option allows to
disable MMAP per device without a compile-time change.
Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
They are not used from anywhere but common.c which is where these are
defined so make them static.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Now that vfio_put_base_device is called unconditionally at instance_finalize
time, it can be called twice if vfio_populate_device fails. This works
but it is slightly harder to follow.
Change vfio_get_device to not touch the vbasedev struct until it will
definitely succeed, moving the vfio_populate_device call back to vfio-pci.
This way, vfio_put_base_device will only be called once.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
A new common module is created. It implements all functions
that have no device specificity (PCI, Platform).
This patch only consists in move (no functional changes)
Signed-off-by: Kim Phillips <kim.phillips@linaro.org>
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This is done in preparation for the addition of VFIO platform
device support.
Signed-off-by: Kim Phillips <kim.phillips@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
