Because guest mask notifier cannot be used in vhost-user mode, a boolean
flag "use_guest_notifier_mask" was added in commit 5669655aaf to disable
the use of guest mask notifier under virtio-pci. However this flag wasn't
checked in other virtio devices, such as virtio-mmio. In our tests, it
caused assertion error under "vhost-user + virtio-mmio". This patch
addresses this problem by adding a check before guest_notifier_mask is
called.
Signed-off-by: Wei Huang <wei@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This will be used to forbid iothread configuration when the
proxy does not allow using ioeventfd. To simplify the implementation,
change the direction of the ioeventfd_disabled callback too.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This simplifies the code and removes the ioeventfd_started
and ioeventfd_set_started callback. The only difference is
in how virtio-ccw handles an error---it doesn't disable
ioeventfd forever anymore. It was the only backend to do
so, and if desired this behavior should be implemented in
virtio-bus.c.
Instead of ioeventfd_started, the ioeventfd_assign callback now
determines whether the virtio bus supports host notifiers.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
At the moment the following QEMU command line triggers an assertion
failure (minimal reproducer by Cole):
qemu-system-aarch64 \
-machine virt-2.6,accel=tcg \
-nodefaults \
-no-user-config \
-nographic -monitor stdio \
-device virtio-scsi-device,id=scsi0 \
-device virtio-scsi-device,id=scsi1 \
-drive file=foo.img,format=raw,if=none,id=d0 \
-device scsi-hd,bus=scsi0.0,drive=d0 \
-drive file=foo.img,format=raw,if=none,id=d1 \
-device scsi-hd,bus=scsi1.0,drive=d1
qemu-system-aarch64: migration/savevm.c:615:
vmstate_register_with_alias_id:
Assertion `!se->compat || se->instance_id == 0' failed.
The reason is that the vmstate sections for the two scsi-hd devices are
not uniquely identifiable by name.
The direct parent buses of the scsi-hd devices -- scsi0.0 and scsi1.0 --
support the BusClass.get_dev_path member function. scsibus_get_dev_path()
formats a device path prefix with the help of its topologically parent
bus, and then appends the chan🆔lun triplet to it. For both scsi-hd
devices, this triplet is 0:0:0.
(Here we use "device path" in the QEMU migration sense, for vmstate
section identification, not in the OFW or UEFI device path senses.)
The virtio-scsi HBA is plugged into the virtio-mmio bus (implemented by
the internal VirtIOMMIOProxy device). This bus class
(TYPE_VIRTIO_MMIO_BUS) inherits, as its get_dev_path() member function,
the virtio_bus_get_dev_path() method from its parent class
(TYPE_VIRTIO_BUS).
virtio_bus_get_dev_path() does not format any kind of device address on
its own; "virtio addresses" are transport-specific. Therefore
virtio_bus_get_dev_path() asks the topologically parent bus of the proxy
object (implementing the specific virtio transport) to format the address
of the proxy object.
(For virtio-pci devices (where the proxy is an instance of VirtIOPCIProxy,
plugged into a PCI bus), this ends up in pcibus_get_dev_path().)
However, VirtIOMMIOProxy is usually (in practice: always) plugged into
"main-system-bus", the singleton TYPE_SYSTEM_BUS object. This BusClass
does not support formatting QEMU vmstate device paths at all (as
SysBusDevice objects can have zero or more IO ports and zero or more MMIO
regions). Hence the formatting request delegated from
virtio_bus_get_dev_path() gets answered with NULL.
The end result is that the two scsi-hd devices end up with the same device
path "0:0:0", which triggers the assert.
We can solve this by recognizing that virtio-mmio transports are
distinguished from each other by their base addresses in MMIO address
space. Implement virtio_mmio_bus_get_dev_path() as follows:
(1) The virtio device whose devpath is to be formatted resides on a
virtio-mmio bus that is implemented by a VirtIOMMIOProxy object. Ask
the parent bus of VirtIOMMIOProxy to format the device path of
VirtIOMMIOProxy, as a path prefix. (This is identical to what
virtio_bus_get_dev_path() does.)
(2) Append the base address of VirtIOMMIOProxy to the device path, such
as:
- virtio-mmio@000000000a003e00,
- virtio-mmio@000000000a003c00.
Given that these device paths are placed in the migration stream, step (2)
above, if done unconditionally, would break migration. So make that step
conditional on a new VirtIOMMIOProxy property, which is enabled for 2.7
machine types and later.
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Cole Robinson <crobinso@redhat.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Kevin Zhao <kevin.zhao@linaro.org>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Tom Hanson <thomas.hanson@linaro.org>
Reported-by: Kevin Zhao <kevin.zhao@linaro.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Message-id: 1467739394-28357-1-git-send-email-lersek@redhat.com
Fixes: https://bugs.launchpad.net/qemu/+bug/1594239
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
For virtio-1 devices, we allow a more complex queue layout that doesn't
require descriptor table and rings on a physically-contigous memory area:
add virtio_queue_set_rings() to allow transports to set this up.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
set_host_notifier and set_guest_notifiers supported by virtio-mmio now.
Most code copied from virtio-pci.
This makes it possible to use vhost-net with virtio-mmio,
improving performance by about 30%.
The kvm-arm does not yet support irqfd, need to fix the hard-coded part after
kvm-arm gets irqfd support.
Signed-off-by: Ying-Shiuan Pan <yingshiuan.pan@gmail.com>
Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Nearly all transports have been offering VIRTIO_F_NOTIFY_ON_EMPTY,
s390-virtio being the exception. There's no reason why it shouldn't
offer it as well, though (handling is done in core anyway), so let's
move it to the common virtio features.
While we're changing it anyway, fix the indentation for the
DEFINE_VIRTIO_COMMON_FEATURES macro.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Move host_features from the individual transport proxies into
the virtio device. Transports may continue to add feature bits
during device plugging.
This should it make easier to offer different sets of host features
for virtio-1/transitional support.
Tested-by: Shannon Zhao <shannon.zhao@linaro.org>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Add virtio_{add,clear}_feature helper functions for manipulating a
feature bits variable. This has some benefits over open coding:
- add check that the bit is in a sane range
- make it obvious at a glance what is going on
- have a central point to change when we want to extend feature bits
Convert existing code manipulating features to use the new helpers.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Bus by default is not hotpluggable.
virtio-mmio-bus and its parent types do not set allow_hotplug
anywhere explicitly, so remove not needed field access
and wrapper along with it.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
Both 'indirect_desc' and 'event_idx' are bus independent features,
and they should be enabled for mmio devices too.
On arm64 quad core VM(qemu-kvm), the patch can increase block I/O
performance a lot with latest linux tree:
- without the patch: 14K IOPS
- with the patch: 34K IOPS
fio script:
[global]
direct=1
bsrange=4k-4k
timeout=10
numjobs=4
ioengine=libaio
iodepth=64
filename=/dev/vdc
group_reporting=1
[f1]
rw=randread
Cc: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
To be passed to object_initialize().
Since commit 39355c3826 the argument is
void*, so drop some superfluous (BusState *) casts or direct parent
field usages.
Signed-off-by: Andreas Färber <afaerber@suse.de>
Add support for the generic MMIO based virtio transport.
This patch includes some fixes for bugs spotted by
Ying-Shiuan Pan <yspan@itri.org.tw>.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Message-id: 1373977512-28932-6-git-send-email-peter.maydell@linaro.org
[Fred changes: updated to new virtio-bus mechanisms]
Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
[PMM changes:
* fixed trivial makefile conflict
* removed unused int_enable
* host_features doesn't need migrating
* reset guest accessible state in the reset function
* minor style fixes like extra blank lines
* RAZ/WI if there's no backend
* made transport size 0x200, in line with kvmtool
* set has_variable_vring_alignment
]
