This reverts commit aad4dce9.

I accidentally merged the wrong version of a pull request
which had a buggy version of this patch. Reverting the
buggy version means we can then cleanly merge in the correct
pull with the corrected change.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

commit a9f98bb5 vhost: multiqueue
support changed the order of stopping the device. Previously
vhost_dev_stop would disable backend and only afterwards, unset guest
notifiers. We now unset guest notifiers while vhost is still
active. This can lose interrupts causing guest networking to fail. In
particular, this has been observed during migration.

To adapt this, several other changes are needed:
- remove the hdev->started assertion in vhost.c since we may want to
start the guest notifiers before vhost starts and stop the guest
notifiers after vhost is stopped.
- introduce the vhost_net_set_vq_index() and call it before setting
guest notifiers. This is used to guarantee vhost_net has the correct
virtqueue index when setting guest notifiers.

Cc: qemu-stable@nongnu.org
Reported-by: N"Zhangjie (HZ)" <zhangjie14@huawei.com>
Tested-by: NWilliam Dauchy <wdauchy@gmail.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NJason Wang <jasowang@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

vhost_verify_ring_mappings leaks mappings on error.
Fix this up.

Cc: qemu-stable@nongnu.org
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

vhost user does not support LOG_ALL feature bit.
Generally, we should not try to set this bit without
checking that backend can support it first.

Detect and block migration.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NNikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Use vhost_set_backend_type to initialise a proper vhost_ops structure.
In vhost_net_init and vhost_net_start_one call conditionally TAP related
initialisation depending on the vhost backend type.
Signed-off-by: NAntonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: NNikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Decouple vhost from the Linux kernel by introducing vhost_ops. The
intention is to provide different backends - a 'kernel' backend based on
the ioctl interface, and an 'user' backend based on a UNIX domain socket
and shared memory interface.
Signed-off-by: NAntonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: NNikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

vhost_dev_init will replace devfd and devpath with a single opaque argument.
This is initialised with a file descriptor. When TAP is used (through
vhost_net), open /dev/vhost-net and pass the fd as an opaque parameter in
VhostNetOptions. The same applies to vhost-scsi - open /dev/vhost-scsi and
pass the fd.
Signed-off-by: NAntonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: NNikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Generalize the features get/ack to be used for both vhost-net and vhost-scsi.
In vhost-net add vhost_net_get_feature_bits to select the feature bit set
depending on the NetClient kind.
Signed-off-by: NNikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

Avoid using the GNU extesion ffsl which is not implemented in musl libc.

The atomic_xchg() means we know that vhost_log_chunk_t will never be
larger than the 'long' type, so ctzl() is always sufficient.

See also commit fbeadf50 (bitops: unify bitops_ffsl with the one in
host-utils.h, call it bitops_ctzl) on why ctzl should be used instead
of ffsl.
Signed-off-by: NNatanael Copa <ncopa@alpinelinux.org>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

When vhost device stops, its implementation synchronizes kernel state
back to virtio.c so we can continue emulating the device
in userspace.

This patch ensures that virtio.c's signalled_used_valid flag is reset so
that userspace does not suppress guest notifications due to stale
signalled_used values.

Cc: qemu-stable@nongnu.org
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

We're already using them in several places, but __sync builtins are just
too ugly to type, and do not provide seqcst load/store operations.
Reviewed-by: NRichard Henderson <rth@twiddle.net>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add ref/unref calls at the following places:

- places where memory regions are stashed by a listener and
  used outside the BQL (including in Xen or KVM).

- memory_region_find callsites

- creation of aliases and containers (only the aliased/contained
  region gets a reference to avoid loops)

- around calls to del_subregion/add_subregion, where the region
  could disappear after the first call
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

So far, the size of all regions passed to listeners could fit in 64 bits,
because artificial regions (containers and aliases) are eliminated by
the memory core, leaving only device regions which have reasonable sizes

An IOMMU however cannot be eliminated by the memory core, and may have
an artificial size, hence we may need 65 bits to represent its size.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This remove virtio-bindings, and use class instead.
Signed-off-by: NKONRAD Frederic <fred.konrad@greensocs.com>
Message-id: 1366791683-5350-6-git-send-email-fred.konrad@greensocs.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This patch follows MST's recommendation to move checks for
vhost_verify_ring_mappings() -> cpu_physical_memory_map() operations
from MemoryListener->region_[add,del]() -> vhost_set_memory() into
final MemoryListener->commit() -> vhost_commit() callback.

It addresses the case where virtio-scsi vq ioport RAM re-mapping
to read-only SeaBIOS ROM triggers a cpu_physical_memory_map()
NIL MemoryRegionSection pointer failure.

Also save vhost_dev->mem_changed_[start,end]_addr values in
vhost_set_memory() for final ranges_overlap checks.  (Thanks Paolo!)

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Asias He <asias@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>
Acked-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Many of these should be cleaned up with proper qdev-/QOM-ification.
Right now there are many catch-all headers in include/hw/ARCH depending
on cpu.h, and this makes it necessary to compile these files per-target.
However, fixing this does not belong in these patches.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Done with this script:

cd hw
for i in `find . -name '*.h' | sed 's/^..//'`; do
  echo '\,^#.*include.*["<]'$i'[">], s,'$i',hw/&,'
done | sed -i -f - `find . -type f`

This is so that paths remain valid as files are moved.

Instead, files in hw/dataplane are referenced with the relative path.
We know they are not going to move to include/, and they are the only
include files that are in subdirectories _and_ move.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This fixes two bugs related to memory sync during
migration:
    - ram address calculation was missing the chunk
      address, so the wrong page was dirtied
    - one after last was used instead of the
      end address of a region, which might overflow to 0
      and cause us to skip the region when the region ends at
      ~0x0ull.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Tested-by: NJason Wang <jasowang@redhat.com>

This patch lets vhost support multiqueue. The idea is simple, just launching
multiple threads of vhost and let each of vhost thread processing a subset of
the virtqueues of the device. After this change each emulated device can have
multiple vhost threads as its backend.

To do this, a virtqueue index were introduced to record to first virtqueue that
will be handled by this vhost_net device. Based on this and nvqs, vhost could
calculate its relative index to setup vhost_net device.

Since we may have many vhost/net devices for a virtio-net device. The setting of
guest notifiers were moved out of the starting/stopping of a specific vhost
thread. The vhost_net_{start|stop}() were renamed to
vhost_net_{start|stop}_one(), and a new vhost_net_{start|stop}() were introduced
to configure the guest notifiers and start/stop all vhost/vhost_net devices.
Signed-off-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Once upon a time, it was decided that qemu_malloc(0) should abort.
Switching to glib retired that bright idea.  Some code that was added
to cope with it (e.g. in commits 702ef63f, b76b6e95) is still around.
Bury it.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Support backend guest notifier masking in vhost-net:
create eventfd at device init, when masked,
make vhost use that as eventfd instead of
sending an interrupt.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

This makes it possible to use started flag for sanity checking
of callbacks that happen during start/stop.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Pass nvqs to set_guest_notifiers. This makes it possible to
save on irqfds by not allocating one for the control vq
for virtio-net.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

target_phys_addr_t is unwieldly, violates the C standard (_t suffixes are
reserved) and its purpose doesn't match the name (most target_phys_addr_t
addresses are not target specific).  Replace it with a finger-friendly,
standards conformant hwaddr.

Outstanding patchsets can be fixed up with the command

  git rebase -i --exec 'find -name "*.[ch]"
                        | xargs s/target_phys_addr_t/hwaddr/g' origin
Signed-off-by: NAvi Kivity <avi@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Using the AddressSpace type reduces confusion, as you can't accidentally
supply the MemoryRegion you're interested in.
Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

Instead of checking manually, let the listener filter for us.  This prepares
us for DMA address spaces.
Signed-off-by: NAvi Kivity <avi@redhat.com>

The path to /dev/vhost-net is currently hardcoded in vhost_dev_init().
This needs to be changed so that /dev/vhost-scsi can be used.  Pass in
the device path instead of hardcoding it.
Signed-off-by: NStefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Under Win32, EventNotifiers will not have event_notifier_get_fd, so we
cannot call it in common code such as hw/virtio-pci.c.  Pass a pointer to
the notifier, and only retrieve the file descriptor in kvm-specific code.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

It's clear from the surrounding code that
start < end so it's enough to assert end < log_size.
However, it's better to make this explicit in case
we refactor the code again.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

When the vhost log is resized, we want to sync up to
the size of the old log.  With that end address in place,
ignore regions that start after then end rather than
hitting assert.

This also addresses the following crash report:
When migrating a vm using vhost-net we hit the following assertion:

qemu-kvm: /usr/src/packages/BUILD/qemu-kvm-0.15.1/hw/vhost.c:30:
vhost_dev_sync_region: Assertion `start / (0x1000 * (8 *
sizeof(vhost_log_chunk_t))) < dev->log_size' failed.

The cases which the end < start check is intended to catch, such as
for vga video memory, will also likely trigger the assertion.
Reorder the code to handle this correctly.
Reported-by: NJosh Durgin <josh.durgin@dreamhost.com>
Signed-off-by: NBruce Rogers <brogers@suse.com>
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Current memory listeners are incremental; that is, they are expected to
maintain their own state, and receive callbacks for changes to that state.

This patch adds support for stateless listeners; these work by receiving
a ->begin() callback (which tells them that new state is coming), a
sequence of ->region_add() and ->region_nop() callbacks, and then a
->commit() callback which signifies the end of the new state.  They should
ignore ->region_del() callbacks.
Signed-off-by: NAvi Kivity <avi@redhat.com>

Ignore any regions not belonging to a specified address space.
Signed-off-by: NAvi Kivity <avi@redhat.com>

This way the accelerator (kvm) can handle them directly.
Signed-off-by: NAvi Kivity <avi@redhat.com>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

This allows reverse iteration, which in turns allows consistent ordering
among multiple listeners:

  l1->add
  l2->add
  l2->del
  l1->del
Signed-off-by: NAvi Kivity <avi@redhat.com>
Reviewed-by: NRichard Henderson <rth@twiddle.net>

Instead of each target knowing or guessing the guest page size,
just pass the desired size of dirtied memory area.
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

All files under GPLv2 will get GPLv2+ changes starting tomorrow.
event_notifier.c and exec-obsolete.h were only ever touched by Red Hat
employees and can be relicensed now.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>