net: vhost stop updates virtio queue state

Make virtio queue suitable for push operation from qemu
after vhost was stopped.

Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com>
Reviewed-by

net: vhost stop updates virtio queue state

Make virtio queue suitable for push operation from qemu
after vhost was stopped.

Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

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virtio: introduce grab/release_ioeventfd to fix vhost

Following the recent refactoring of virtio notifiers [1], more specifically
the patch ed08a2a0b ("virtio: use virtio_bus_set_host_notifier to
st

virtio: introduce grab/release_ioeventfd to fix vhost

Following the recent refactoring of virtio notifiers [1], more specifically
the patch ed08a2a0b ("virtio: use virtio_bus_set_host_notifier to
start/stop ioeventfd") that uses virtio_bus_set_host_notifier [2]
by default, core virtio code requires 'ioeventfd_started' to be set
to true/false when the host notifiers are configured.

When vhost is stopped and started, however, there is a stop followed by
another start. Since ioeventfd_started was never set to true, the 'stop'
operation triggered by virtio_bus_set_host_notifier() will not result
in a call to virtio_pci_ioeventfd_assign(assign=false). This leaves
the memory regions with stale notifiers and results on the next start
triggering the following assertion:

kvm_mem_ioeventfd_add: error adding ioeventfd: File exists
Aborted

This patch reintroduces (hopefully in a cleaner way) the concept
that was present with ioeventfd_disabled before the refactoring.
When ioeventfd_grabbed>0, ioeventfd_started tracks whether ioeventfd
should be enabled or not, but ioeventfd is actually not started at
all until vhost releases the host notifiers.

[1] http://lists.nongnu.org/archive/html/qemu-devel/2016-10/msg07748.html
[2] http://lists.nongnu.org/archive/html/qemu-devel/2016-10/msg07760.html

Reported-by: Felipe Franciosi <felipe@nutanix.com>
Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reported-by: Alex Williamson <alex.williamson@redhat.com>
Fixes: ed08a2a0b ("virtio: use virtio_bus_set_host_notifier to start/stop ioeventfd")
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Tested-by: Farhan Ali <alifm@linux.vnet.ibm.com>
Tested-by: Alex Williamson <alex.williamson@redhat.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>

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vhost: drop legacy vring layout bits

The legacy vring layout is not used anymore as we use the separate
mappings even for legacy devices.
This patch simply removes it.

This also fixes a bug with vi

vhost: drop legacy vring layout bits

The legacy vring layout is not used anymore as we use the separate
mappings even for legacy devices.
This patch simply removes it.

This also fixes a bug with virtio 1 devices when the vring descriptor table
is mapped at a higher address than the used vring because the following
function may return an insanely great value:

hwaddr virtio_queue_get_ring_size(VirtIODevice *vdev, int n)
{
return vdev->vq[n].vring.used - vdev->vq[n].vring.desc +
virtio_queue_get_used_size(vdev, n);
}

and the mapping fails.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-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>

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vhost: adapt vhost_verify_ring_mappings() to virtio 1 ring layout

With virtio 1, the vring layout is split in 3 separate regions of
contiguous memory for the descriptor table, the available ring and

vhost: adapt vhost_verify_ring_mappings() to virtio 1 ring layout

With virtio 1, the vring layout is split in 3 separate regions of
contiguous memory for the descriptor table, the available ring and the
used ring, as opposed with legacy virtio which uses a single region.

In case of memory re-mapping, the code ensures it doesn't affect the
vring mapping. This is done in vhost_verify_ring_mappings() which assumes
the device is legacy.

This patch changes vhost_verify_ring_mappings() to check the mappings of
each part of the vring separately.

This works for legacy mappings as well.

Cc: qemu-stable@nongnu.org
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-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>

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vhost: migration blocker only if shared log is used

Commit 31190ed7 added a migration blocker in vhost_dev_init() to
check if memfd would succeed. It is better if this blocker first
checks if vhost

vhost: migration blocker only if shared log is used

Commit 31190ed7 added a migration blocker in vhost_dev_init() to
check if memfd would succeed. It is better if this blocker first
checks if vhost backend requires shared log. This will avoid a
situation where a blocker is added inappropriately (e.g. shared
log allocation fails when vhost backend doesn't support it).

Signed-off-by: Rafael David Tinoco <rafael.tinoco@canonical.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

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virtio: remove ioeventfd_disabled altogether

Now that there is not anymore a switch from the generic ioeventfd handler
to the dataplane handler, virtio_bus_set_host_notifier(assign=true) is
always c

virtio: remove ioeventfd_disabled altogether

Now that there is not anymore a switch from the generic ioeventfd handler
to the dataplane handler, virtio_bus_set_host_notifier(assign=true) is
always called with !bus->ioeventfd_started, hence virtio_bus_stop_ioeventfd
does nothing in this case. Move the invocation to vhost.c, which is the
only place that needs it.

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>

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virtio: move ioeventfd_started flag to VirtioBusState

This simplifies the code and removes the ioeventfd_started
and ioeventfd_set_started callback. The only difference is
in how virtio-ccw handles

virtio: move ioeventfd_started flag to VirtioBusState

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>

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vhost: don't set vring call if no vector

We used to set vring call fd unconditionally even if guest driver does
not use MSIX for this vritqueue at all. This will cause lots of
unnecessary userspace

vhost: don't set vring call if no vector

We used to set vring call fd unconditionally even if guest driver does
not use MSIX for this vritqueue at all. This will cause lots of
unnecessary userspace access and other checks for drivers does not use
interrupt at all (e.g virtio-net pmd). So check and clean vring call
fd if guest does not use any vector for this virtqueue at
all.

Perf diffs (on rx) shows lots of cpus wasted on vhost_signal() were saved:

#
28.12% -27.82% [vhost] [k] vhost_signal
14.44% -1.69% [kernel.vmlinux] [k] copy_user_generic_string
7.05% +1.53% [kernel.vmlinux] [k] __free_page_frag
6.51% +5.53% [vhost] [k] vhost_get_vq_desc
...

Pktgen tests shows 15.8% improvement on rx pps and 6.5% on tx pps.

Before: RX 2.08Mpps TX 1.35Mpps
After: RX 2.41Mpps TX 1.44Mpps

Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

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vhost: do not update last avail idx on get_vring_base() failure

The state.num value will probably be 0 in this case, but that
doesn't make sense to update.

Signed-off-by: Marc-André Lureau <marcand

vhost: do not update last avail idx on get_vring_base() failure

The state.num value will probably be 0 in this case, but that
doesn't make sense to update.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

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vhost: add vhost_net_set_backend()

Not all vhost-user backends support ops->vhost_net_set_backend(). It is
a nicer to provide an assert/error than to crash trying to
call. Furthermore, it improves a

vhost: add vhost_net_set_backend()

Not all vhost-user backends support ops->vhost_net_set_backend(). It is
a nicer to provide an assert/error than to crash trying to
call. Furthermore, it improves a bit the code by hiding vhost_ops
details.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

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vhost: add assert() to check runtime behaviour

All these functions must be called only after the backend is connected.
They are called from virtio-net.c, after either virtio or link status
change.

vhost: add assert() to check runtime behaviour

All these functions must be called only after the backend is connected.
They are called from virtio-net.c, after either virtio or link status
change.

The check for nc->peer->link_down should ensure vhost_net_{start,stop}()
are always called between vhost_user_{start,stop}().

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

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vhost: use error_report() instead of fprintf(stderr,...)

Let's use qemu proper error reporting API, this ensures the error is
reported at the right place (stderr or monitor), with a conventional
for

vhost: use error_report() instead of fprintf(stderr,...)

Let's use qemu proper error reporting API, this ensures the error is
reported at the right place (stderr or monitor), with a conventional
format.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

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vhost: add missing VHOST_OPS_DEBUG

Add missing VHOST_OPS_DEBUG() logs, for completeness.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.c

vhost: add missing VHOST_OPS_DEBUG

Add missing VHOST_OPS_DEBUG() logs, for completeness.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

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vhost: do not assert() on vhost_ops failure

Calling a vhost operation may fail, for example with disconnected
vhost-user backend, but qemu shouldn't abort in this case.

Log an error instead, except

vhost: do not assert() on vhost_ops failure

Calling a vhost operation may fail, for example with disconnected
vhost-user backend, but qemu shouldn't abort in this case.

Log an error instead, except on error and cleanup code paths where it
can be mostly ignored.

Let's use a VHOST_OPS_DEBUG macro to easily disable those messages once
disconnected backend stabilizes.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

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vhost: fix calling vhost_dev_cleanup() after vhost_dev_init()

vhost_net_init() calls vhost_dev_init() and in case of failure, calls
vhost_dev_cleanup() directly. However, the structure is already
pa

vhost: fix calling vhost_dev_cleanup() after vhost_dev_init()

vhost_net_init() calls vhost_dev_init() and in case of failure, calls
vhost_dev_cleanup() directly. However, the structure is already
partially cleaned on error. Calling vhost_dev_cleanup() again will call
vhost_virtqueue_cleanup() on already clean queues, and causing potential
double-close. Instead, adjust dev->nvqs and simplify vhost_dev_init()
code to not call vhost_virtqueue_cleanup() but vhost_dev_cleanup()
instead.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Ilya Maximets <i.maximets@samsung.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

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vhost: make vhost_dev_cleanup() idempotent

It is called on multiple code path, so make it safe to call several
times (note: I don't remember a reproducer here, but a function called
'cleanup' should

vhost: make vhost_dev_cleanup() idempotent

It is called on multiple code path, so make it safe to call several
times (note: I don't remember a reproducer here, but a function called
'cleanup' should probably be idempotent in my book)

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

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vhost: fix cleanup on not fully initialized device

If vhost_dev_init() failed, caller may still call vhost_dev_cleanup()
later. However, vhost_dev_cleanup() tries to remove the device from the
list

vhost: fix cleanup on not fully initialized device

If vhost_dev_init() failed, caller may still call vhost_dev_cleanup()
later. However, vhost_dev_cleanup() tries to remove the device from the
list even if it wasn't yet added, which may lead to crashes. Similarly
for the memory listener.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

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vhost: assert the log was cleaned up

Make sure the log was released on cleanup, or it will leak (the
alternative is to call vhost_log_put() unconditionally, but it may hide
some dev state issues).

vhost: assert the log was cleaned up

Make sure the log was released on cleanup, or it will leak (the
alternative is to call vhost_log_put() unconditionally, but it may hide
some dev state issues).

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

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vhost: make vhost_log_put() idempotent

Although not strictly required, it is nice to have vhost_log_put()
safely callable multiple times.

Clear dev->log* when calling vhost_log_put() to make the fu

vhost: make vhost_log_put() idempotent

Although not strictly required, it is nice to have vhost_log_put()
safely callable multiple times.

Clear dev->log* when calling vhost_log_put() to make the function
idempotent. This also simplifies a bit the caller work.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

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vhost: don't assume opaque is a fd, use backend cleanup

vhost-dev opaque isn't necessarily an fd, it can be a chardev when using
vhost-user. Goto fail, so vhost_backend_cleanup() is called to handle

vhost: don't assume opaque is a fd, use backend cleanup

vhost-dev opaque isn't necessarily an fd, it can be a chardev when using
vhost-user. Goto fail, so vhost_backend_cleanup() is called to handle
backend cleanup appropriately.

vhost_set_backend_type() should never fail, use an assert().

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

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tap: vhost busy polling support

This patch add the capability of basic vhost net busy polling which is
supported by recent kernel. User could configure the maximum number of
us that could be spent o

tap: vhost busy polling support

This patch add the capability of basic vhost net busy polling which is
supported by recent kernel. User could configure the maximum number of
us that could be spent on busy polling through a new property of tap
"poll-us".

Cc: Greg Kurz <groug@kaod.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>

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virtio-bus: remove old set_host_notifier callback

All users have been converted to the new ioevent callbacks.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Fam Zheng <famz@re

virtio-bus: remove old set_host_notifier callback

All users have been converted to the new ioevent callbacks.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

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virtio-bus: have callers tolerate new host notifier api

Have vhost and dataplane use the new api for transports that
have been converted.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Rev

virtio-bus: have callers tolerate new host notifier api

Have vhost and dataplane use the new api for transports that
have been converted.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

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virtio: move bi-endian target support to a single location

Paolo's recent cpu.h cleanups broke legacy virtio for ppc64 LE guests (and
arm BE guests as well, even if I have not verified that). Especi

virtio: move bi-endian target support to a single location

Paolo's recent cpu.h cleanups broke legacy virtio for ppc64 LE guests (and
arm BE guests as well, even if I have not verified that). Especially, commit
"33c11879fd42 qemu-common: push cpu.h inclusion out of qemu-common.h" has
the side-effect of silently hiding the TARGET_IS_BIENDIAN macro from the
virtio memory accessors, and thus fully disabling support of endian changing
targets.

To be sure this cannot happen again, let's gather all the bi-endian bits
where they belong in include/hw/virtio/virtio-access.h.

The changes in hw/virtio/vhost.c are safe because vhost_needs_vring_endian()
is not called on a hot path and non bi-endian targets will return false
anyway.

While here, also rename TARGET_IS_BIENDIAN to be more precise: it is only for
legacy virtio and bi-endian guests.

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>

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include/qemu/osdep.h: Don't include qapi/error.h

Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the
Error typedef. Since then, we've moved to include qemu/osdep.h
everywhere. Its fi

include/qemu/osdep.h: Don't include qapi/error.h

Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the
Error typedef. Since then, we've moved to include qemu/osdep.h
everywhere. Its file comment explains: "To avoid getting into
possible circular include dependencies, this file should not include
any other QEMU headers, with the exceptions of config-host.h,
compiler.h, os-posix.h and os-win32.h, all of which are doing a
similar job to this file and are under similar constraints."
qapi/error.h doesn't do a similar job, and it doesn't adhere to
similar constraints: it includes qapi-types.h. That's in excess of
100KiB of crap most .c files don't actually need.

Add the typedef to qemu/typedefs.h, and include that instead of
qapi/error.h. Include qapi/error.h in .c files that need it and don't
get it now. Include qapi-types.h in qom/object.h for uint16List.

Update scripts/clean-includes accordingly. Update it further to match
reality: replace config.h by config-target.h, add sysemu/os-posix.h,
sysemu/os-win32.h. Update the list of includes in the qemu/osdep.h
comment quoted above similarly.

This reduces the number of objects depending on qapi/error.h from "all
of them" to less than a third. Unfortunately, the number depending on
qapi-types.h shrinks only a little. More work is needed for that one.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
[Fix compilation without the spice devel packages. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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