When a live migration is started the log address to mark dirty pages is provided
to the vhost backend through the vhost_dev_set_log function.
This function is called for each queue pairs but the queue index is wrongly set:
always set to the first queue pair. Then vhost backend lost descriptor addresses
of the queue pairs greater than 1 and behaviour of the vhost backend is
unpredictable.
The queue index is computed by taking account of the vq_index (to retrieve the
queue pair index) and calling the vhost_get_vq_index method of the backend.
Signed-off-by: Thibaut Collet <thibaut.collet@6wind.com>
Cc: qemu-stable@nongnu.org
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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>
Tested-by: Thibaut Collet <thibaut.collet@6wind.com>
Replace the generic vhost_call() by specific functions for each
function call to help with type safety and changing arguments.
While doing this, I found that "unsigned long long" and "uint64_t" were
used interchangeably and causing compilation warnings, using uint64_t
instead, as the vhost & protocol specifies.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
[Fix enum usage and MQ - Thibaut Collet]
Signed-off-by: Thibaut Collet <thibaut.collet@6wind.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Thibaut Collet <thibaut.collet@6wind.com>
If VHOST_USER_PROTOCOL_F_LOG_SHMFD is not announced, block vhost-user
migration. The blocker is removed in vhost_dev_cleanup().
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>
Tested-by: Thibaut Collet <thibaut.collet@6wind.com>
Send the shm for the dirty pages logging if the backend supports
VHOST_USER_PROTOCOL_F_LOG_SHMFD. Wait for a reply to make sure
the old log is no longer used.
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>
Tested-by: Thibaut Collet <thibaut.collet@6wind.com>
If the backend is requires it, allocate shareable memory.
vhost_log_get() now uses 2 globals "vhost_log" and "vhost_log_shm", that
way there is a common non-shareable log and a common shareable one.
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>
Tested-by: Thibaut Collet <thibaut.collet@6wind.com>
Split VHOST_SET_LOG_BASE call in a seperate function callback, so that
type safety works and more arguments can be added in the next patches.
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>
Tested-by: Thibaut Collet <thibaut.collet@6wind.com>
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>
Tested-by: Thibaut Collet <thibaut.collet@6wind.com>
Don't initialize vhost backend if memslots number exceeds the supported
limit. This prevents failures down the road when backend
is actually started.
[MST: rewrite commit log]
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
it will allow for other parts of QEMU check if it's safe
to map memory region during hotplug/runtime.
That way hotplug path will have a chance to cancel
hotplug operation instead of crashing in vhost_commit().
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This patch is initially based a patch from Nikolay Nikolaev.
This patch adds vhost-user multiple queue support, by creating a nc
and vhost_net pair for each queue.
Qemu exits if find that the backend can't support the number of requested
queues (by providing queues=# option). The max number is queried by a
new message, VHOST_USER_GET_QUEUE_NUM, and is sent only when protocol
feature VHOST_USER_PROTOCOL_F_MQ is present first.
The max queue check is done at vhost-user initiation stage. We initiate
one queue first, which, in the meantime, also gets the max_queues the
backend supports.
In older version, it was reported that some messages are sent more times
than necessary. Here we came an agreement with Michael that we could
categorize vhost user messages to 2 types: non-vring specific messages,
which should be sent only once, and vring specific messages, which should
be sent per queue.
Here I introduced a helper function vhost_user_one_time_request(), which
lists following messages as non-vring specific messages:
VHOST_USER_SET_OWNER
VHOST_USER_RESET_DEVICE
VHOST_USER_SET_MEM_TABLE
VHOST_USER_GET_QUEUE_NUM
For above messages, we simply ignore them when they are not sent the first
time.
Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Signed-off-by: Changchun Ouyang <changchun.ouyang@intel.com>
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Tested-by: Marcel Apfelbaum <marcel@redhat.com>
Minusing the idx with the base(dev->vq_index) for vhost-kernel, and
then adding it back for vhost-user doesn't seem right. Here introduces
a new method vhost_backend_get_vq_index() for getting the right vq
index for following vhost messages calls.
Suggested-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Tested-by: Marcel Apfelbaum <marcel@redhat.com>
Commit ef546f1275 ("virtio: add
feature checking helpers") introduced a helper __virtio_has_feature.
We don't want to use reserved identifiers, though, so let's
rename __virtio_has_feature to virtio_has_feature and virtio_has_feature
to virtio_vdev_has_feature.
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>
We override the error value r in fail_vq, this will cause the caller
can't detect the failure which may cause the caller may disable the
notifiers twice if vhost is failed to start. Fix this by using another
variable to keep track the return value of set_host_notifier().
Fixes b0b3db7955 ("vhost-net: cleanup
host notifiers at last step")
Cc: qemu-stable@nongnu.org
Cc: Michael S. Tsirkin <mst@redhat.com>
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>
Most notably this includes virtio cross-endian patches.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging
virtio, pci fixes, enhancements
Most notably this includes virtio cross-endian patches.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
# gpg: Signature made Fri Jun 19 11:18:05 2015 BST using RSA key ID D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>"
# gpg: aka "Michael S. Tsirkin <mst@redhat.com>"
* remotes/mst/tags/for_upstream:
vhost: enable vhost without without MSI-X
pci: Don't register a specialized 'config_write' if default behavior is intended
hw/core: rebase sysbus_get_fw_dev_path() to g_strdup_printf()
vhost_net: re-enable when cross endian
vhost-net: tell tap backend about the vnet endianness
tap: fix non-linux build
tap: add VNET_LE/VNET_BE operations
vhost: set vring endianness for legacy virtio
virtio: introduce virtio_legacy_is_cross_endian()
linux-headers: sync vhost.h
vhost-user: part of virtio
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
We use vhostforce to enable vhost even if Guests don't have MSI-X
support and we fall back to QEMU virtio-net.
This gives a very small performance gain, but the disadvantage
is that guest now controls which virtio code is running
(qemu or vhost) so our attack surface is doubled.
This patch will enable vhost unconditionally whenever it's requested.
For compatibility, enable vhost when vhostforce is set, as well.
Signed-off-by: Pankaj Gupta <pagupta@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Legacy virtio is native endian: if the guest and host endianness differ,
we have to tell vhost so it can swap bytes where appropriate. This is
done through a vhost ring ioctl.
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>
Most notably this includes virtio 1 patches
Still not all devices converted, and not fully spec compliant,
so disabled by default.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging
pc, acpi, virtio
Most notably this includes virtio 1 patches
Still not all devices converted, and not fully spec compliant,
so disabled by default.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
# gpg: Signature made Thu Jun 11 12:53:08 2015 BST using RSA key ID D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>"
# gpg: aka "Michael S. Tsirkin <mst@redhat.com>"
* remotes/mst/tags/for_upstream: (42 commits)
i386/acpi-build: fix PXB workarounds for unsupported BIOSes
i386/acpi-build: more traditional _UID and _HID for PXB root buses
vhost-scsi: move qdev properties into vhost-scsi.c
virtio-9p-device: move qdev properties into virtio-9p-device.c
virtio-serial-bus: move qdev properties into virtio-serial-bus.c
virtio-rng: move qdev properties into virtio-rng.c
virtio-scsi: move qdev properties into virtio-scsi.c
virtio-net.h: Remove unsed DEFINE_VIRTIO_NET_PROPERTIES
virtio-net: move qdev properties into virtio-net.c
virtio-input: emulated devices [pci]
virtio-input: core code & base class [pci]
pci: add PCI_CLASS_INPUT_*
virtio-pci: fill VirtIOPCIRegions early.
virtio-pci: drop identical virtio_pci_cap
virtio-pci: move cap type to VirtIOPCIRegion
virtio-pci: move virtio_pci_add_mem_cap call to virtio_pci_modern_region_map
virtio-pci: add virtio_pci_modern_region_map()
virtio-pci: add virtio_pci_modern_regions_init()
virtio-pci: add struct VirtIOPCIRegion for virtio-1 regions
virtio-balloon: switch to virtio_add_feature
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Make sure that all vhost interfaces use 64 bit features, as the virtio
core does, and make sure to use ULL everywhere possible to be on the
safe side.
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>
We allocate an dummy log even if the size is zero. So we should put it
unconditionally too.
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>
When the dirty log mask will also cover other bits than DIRTY_MEMORY_VGA,
some listeners may be interested in the overall zero/non-zero value of
the dirty log mask; others may be interested in the value of single bits.
For this reason, always call log_start/log_stop if bits have respectively
appeared or disappeared, and pass the old and new values of the dirty log
mask so that listeners can distinguish the kinds of change.
For example, KVM checks if dirty logging used to be completely disabled
(in log_start) or is now completely disabled (in log_stop). On the
other hand, Xen has to check manually if DIRTY_MEMORY_VGA changed,
since that is the only bit it cares about.
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
For now memory regions only track DIRTY_MEMORY_VGA individually, but
this will change soon. To support this, split memory_region_is_logging
in two functions: one that returns a given bit from dirty_log_mask,
and one that returns the entire mask. memory_region_is_logging gets an
extra parameter so that the compiler flags misuse.
While VGA-specific users (including the Xen listener!) will want to keep
checking that bit, KVM and vhost check for "any bit except migration"
(because migration is handled via the global start/stop listener
callbacks).
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently we allocate one vhost log per vhost device. This is sub
optimal when:
- Guest has several device with vhost as backend
- Guest has multiqueue devices
In the above cases, we can avoid the memory allocation by sharing a
single vhost log among all the vhost devices. This is done through:
- Introducing a new vhost_log structure with refcnt inside.
- Using a global pointer to vhost_log structure that will be used. And
introduce helper to get the log with expected log size and helper to
- drop the refcnt to the old log.
- Each vhost device still keep track of a pointer to the log that was
used.
With above, if no resize happens, all vhost device will share a single
vhost log. During resize, a new vhost_log structure will be allocated
and made for the global pointer. And each vhost devices will drop the
refcnt to the old log.
Tested by doing scp during migration for a 2 queues virtio-net-pci.
Cc: Michael S. Tsirkin <mst@redhat.com>
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>
VHOST_SET_LOG_BASE got an incorrect address, causing
migration errors and potentially even memory corruption.
Reported-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Amos Kong <akong@redhat.com>
Message-id: 1429283565-32265-1-git-send-email-mst@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-id: 1417166789-1960-1-git-send-email-arei.gonglei@huawei.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
commit a9f98bb5eb "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 fix 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 to guarantee vhost_net has the correct
virtqueue index when setting guest notifiers.
MST: fix up error handling.
Cc: qemu-stable@nongnu.org
Cc: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Andrey Korolyov <andrey@xdel.ru>
Reported-by: "Zhangjie (HZ)" <zhangjie14@huawei.com>
Tested-by: William Dauchy <william@gandi.net>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael 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: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael 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: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael 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: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael 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: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael 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: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eric 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: Natanael Copa <ncopa@alpinelinux.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Peter 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: Michael 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: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo 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: Paolo 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: Paolo Bonzini <pbonzini@redhat.com>
This remove virtio-bindings, and use class instead.
Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Message-id: 1366791683-5350-6-git-send-email-fred.konrad@greensocs.com
Signed-off-by: Anthony 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: Nicholas Bellinger <nab@linux-iscsi.org>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
