This patch series is the QEMU counterpart to the KVM/kernel support for
guest dedicated crypto adapters. The KVM/kernel model is built on the
VFIO mediated device framework and provides the infrastructure for
granting exclusive guest access to crypto devices installed on the linux
host. This patch series introduces a new QEMU command line option, QEMU
object model and CPU model features to exploit the KVM/kernel model.
See the detailed specifications for AP virtualization provided by this
patch set in docs/vfio-ap.txt for a more complete discussion of the
design introduced by this patch series.
v2 -> v3 Change log:
===================
* The corresponding KVM/kernel patch series defined a new device attribute
to the KVM_S390_VM_CRYPTO attribute group to set interpretive execution
of AP instructions for the guest. Now, when the vfio-ap device is
realized, the KVM_SET_DEVICE_ATTR ioctl is invoked to enable
interpretation of AP instructions executed on the guest.
* When the CPU model feature indicating AP instructions are supported for
the guest (i.e., -cpu xxxx,ap=on), the expectation is that the AP bus
will be initialized on the guest. In v2, however; AP instructions were
intercepted unless a vfio-ap device (i.e., -device vfio-ap,sysfsdev=$path)
was defined for the guest. Since there were no handlers defined to
process intercepted AP instructions, an operation exception was injected
into the guest causing the AP bus to fail initialization. The v3 version
adds handlers for intercepted AP instructions that incorporate the
following logic:
If the CPU model indicates AP instructions are installed
Set the status response code for the instruction to indicate that
the APQN contained in the instruction is not valid. This is actually
true because the AP devices are configured for the guest via the
sysfs attribute files of the vfio-ap device, so any APQN would not
be valid.
Else
Return an error from the handler. This will cause an operation
exception to be injected into the guest in which case the AP bus
would not initialize. This is the same behavior as exists prior to
the introduction of this patch series.
* Miscellaneous code formatting and other trivial changes.
Tony Krowiak (7):
linux-headers: linux header updates for AP support
s390x/ap: base Adjunct Processor (AP) object
s390x/cpumodel: Set up CPU model for AP device support
s390x/kvm: interface to interpret AP instructions
s390x/vfio: ap: Introduce VFIO AP device
s390x/kvm: handle AP instruction interception
s390: doc: detailed specifications for AP virtualization
default-configs/s390x-softmmu.mak | 1 +
docs/vfio-ap.txt | 624 +++++++++++++++++++++++++++++++++++++
hw/s390x/Makefile.objs | 1 +
hw/s390x/ap-device.c | 38 +++
hw/vfio/Makefile.objs | 1 +
hw/vfio/ap.c | 229 ++++++++++++++
include/hw/s390x/ap-device.h | 44 +++
include/hw/vfio/vfio-common.h | 1 +
linux-headers/asm-s390/kvm.h | 2 +
linux-headers/linux/vfio.h | 2 +
target/s390x/cpu_features.c | 3 +
target/s390x/cpu_features_def.h | 3 +
target/s390x/cpu_models.c | 2 +
target/s390x/gen-features.c | 3 +
target/s390x/kvm.c | 31 ++
target/s390x/kvm_s390x.h | 2 +
16 files changed, 987 insertions(+), 0 deletions(-)
create mode 100644 docs/vfio-ap.txt
create mode 100644 hw/s390x/ap-device.c
create mode 100644 hw/vfio/ap.c
create mode 100644 include/hw/s390x/ap-device.h
