While being at it add a #define for the magic 0x1040 number.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Message-Id: <20221004112100.301935-6-kraxel@redhat.com>
Not needed for a virtio 1.0 device. virtio_pci_device_plugged()
overrides them anyway (so no functional change).
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20221004112100.301935-3-kraxel@redhat.com>
Not needed for a virtio 1.0 device. virtio_pci_device_plugged()
overrides them anyway (so no functional change).
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Message-Id: <20221004112100.301935-2-kraxel@redhat.com>
This new command shows the information of a VirtQueue element.
[Note: Up until v10 of this patch series, virtio.json had many (15+)
enums defined (e.g. decoded device features, statuses, etc.). In v10
most of these enums were removed and replaced with string literals.
By doing this we get (1) simpler schema, (2) smaller generated code,
and (3) less maintenance burden for when new things are added (e.g.
devices, device features, etc.).]
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com>
Message-Id: <1660220684-24909-6-git-send-email-jonah.palmer@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
These new commands show the internal status of a VirtIODevice's
VirtQueue and a vhost device's vhost_virtqueue (if active).
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com>
Message-Id: <1660220684-24909-5-git-send-email-jonah.palmer@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Display feature names instead of bitmaps for host, guest, and
backend for VirtIODevices.
Display status names instead of bitmaps for VirtIODevices.
Display feature names instead of bitmaps for backend, protocol,
acked, and features (hdev->features) for vhost devices.
Decode features according to device ID. Decode statuses
according to configuration status bitmap (config_status_map).
Decode vhost user protocol features according to vhost user
protocol bitmap (vhost_user_protocol_map).
Transport features are on the first line. Undecoded bits (if
any) are stored in a separate field.
[Jonah: Several changes made to this patch from prev. version (v14):
- Moved all device features mappings to hw/virtio/virtio.c
- Renamed device features mappings (less generic)
- Generalized @FEATURE_ENTRY macro for all device mappings
- Virtio device feature map definitions include descriptions of
feature bits
- Moved @VHOST_USER_F_PROTOCOL_FEATURES feature bit from transport
feature map to vhost-user-supported device feature mappings
(blk, fs, i2c, rng, net, gpu, input, scsi, vsock)
- New feature bit added for virtio-vsock: @VIRTIO_VSOCK_F_SEQPACKET
- New feature bit added for virtio-iommu: @VIRTIO_IOMMU_F_BYPASS_CONFIG
- New feature bit added for virtio-mem: @VIRTIO_MEM_F_UNPLUGGED_INACCESSIBLE
- New virtio transport feature bit added: @VIRTIO_F_IN_ORDER
- Added device feature map definition for virtio-rng
]
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com>
Message-Id: <1660220684-24909-4-git-send-email-jonah.palmer@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This new command shows the status of a VirtIODevice, including
its corresponding vhost device's status (if active).
Next patch will improve output by decoding feature bits, including
vhost device's feature bits (backend, protocol, acked, and features).
Also will decode status bits of a VirtIODevice.
[Jonah: From patch v12; added a check to @virtio_device_find to ensure
synchronicity between @virtio_list and the devices in the QOM
composition tree.]
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com>
Message-Id: <1660220684-24909-3-git-send-email-jonah.palmer@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This new command lists all the instances of VirtIODevices with
their canonical QOM path and name.
[Jonah: @virtio_list duplicates information that already exists in
the QOM composition tree. However, extracting necessary information
from this tree seems to be a bit convoluted.
Instead, we still create our own list of realized virtio devices
but use @qmp_qom_get with the device's canonical QOM path to confirm
that the device exists and is realized. If the device exists but
is actually not realized, then we remove it from our list (for
synchronicity to the QOM composition tree).
Also, the QMP command @x-query-virtio is redundant as @qom-list
and @qom-get are sufficient to search '/machine/' for realized
virtio devices. However, @x-query-virtio is much more convenient
in listing realized virtio devices.]
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com>
Message-Id: <1660220684-24909-2-git-send-email-jonah.palmer@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This is the first step towards moving all device config size calculation
logic into the virtio core code. In particular, this adds a struct that
contains all the necessary information for common virtio code to be able
to calculate the final config size for a device. This is expected to be
used with the new virtio_get_config_size helper, which calculates the
final length based on the provided host features.
This builds on top of already existing code like VirtIOFeature and
virtio_feature_get_config_size(), but adds additional fields, as well as
sanity checking so that device-specifc code doesn't have to duplicate it.
An example usage would be:
static const VirtIOFeature dev_features[] = {
{.flags = 1ULL << FEATURE_1_BIT,
.end = endof(struct virtio_dev_config, feature_1)},
{.flags = 1ULL << FEATURE_2_BIT,
.end = endof(struct virtio_dev_config, feature_2)},
{}
};
static const VirtIOConfigSizeParams dev_cfg_size_params = {
.min_size = DEV_BASE_CONFIG_SIZE,
.max_size = sizeof(struct virtio_dev_config),
.feature_sizes = dev_features
};
// code inside my_dev_device_realize()
size_t config_size = virtio_get_config_size(&dev_cfg_size_params,
host_features);
virtio_init(vdev, VIRTIO_ID_MYDEV, config_size);
Currently every device is expected to write its own boilerplate from the
example above in device_realize(), however, the next step of this
transition is moving VirtIOConfigSizeParams into VirtioDeviceClass,
so that it can be done automatically by the virtio initialization code.
All of the users of virtio_feature_get_config_size have been converted
to use virtio_get_config_size so it's no longer needed and is removed
with this commit.
Signed-off-by: Daniil Tatianin <d-tatianin@yandex-team.ru>
Message-Id: <20220906073111.353245-2-d-tatianin@yandex-team.ru>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This allows is to instantiate a vhost-user-gpio device as part of a PCI
bus. It is mostly boilerplate which looks pretty similar to the
vhost-user-fs-pci device.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <5f560cab92d0d789b1c94295ec74b9952907d69d.1641987128.git.viresh.kumar@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220802095010.3330793-14-alex.bennee@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This creates the QEMU side of the vhost-user-gpio device which connects
to the remote daemon. It is based of vhost-user-i2c code.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <5390324a748194a21bc99b1538e19761a8c64092.1641987128.git.viresh.kumar@linaro.org>
[AJB: fixes for qtest, tweaks to feature bits]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Cc: Vincent Whitchurch <vincent.whitchurch@axis.com>
Message-Id: <20220802095010.3330793-13-alex.bennee@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The `started` field is manipulated internally within the vhost code
except for one place, vhost-user-blk via f5b22d06fb (vhost: recheck
dev state in the vhost_migration_log routine). Mark that as a FIXME
because it introduces a potential race. I think the referenced fix
should be tracking its state locally.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220802095010.3330793-12-alex.bennee@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Raphael Norwitz <raphael.norwittz@nutanix.com>
All the boilerplate virtio code does the same thing (or should at
least) of checking to see if the VM is running before attempting to
start VirtIO. Push the logic up to the common function to avoid
getting a copy and paste wrong.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220802095010.3330793-11-alex.bennee@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
These are useful for tracing the lifetime of vhost-user connections.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220802095010.3330793-10-alex.bennee@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
If the guest driver attempts to use the UNUSED(30) bit it is
potentially buggy as 6.3 Legacy Interface: Reserved Feature Bits
states it "SHOULD NOT be negotiated". For now just log this guest
error.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220802095010.3330793-9-alex.bennee@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220802095010.3330793-8-alex.bennee@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
There are some extra bits used over a vhost-user connection which are
hidden from the device itself. We need to set them here to ensure we
enable things like the protocol extensions.
Currently net/vhost-user.c has it's own inscrutable way of persisting
this data but it really should live in the core vhost_user code.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220726192150.2435175-7-alex.bennee@linaro.org>
Message-Id: <20220802095010.3330793-2-alex.bennee@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
g_new(T, n) is neater than g_malloc(sizeof(T) * n). It's also safer,
for two reasons. One, it catches multiplication overflowing size_t.
Two, it returns T * rather than void *, which lets the compiler catch
more type errors.
This commit only touches allocations with size arguments of the form
sizeof(T).
Patch created mechanically with:
$ spatch --in-place --sp-file scripts/coccinelle/use-g_new-etc.cocci \
--macro-file scripts/cocci-macro-file.h FILES...
The previous iteration was commit a95942b50c.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20220923084254.4173111-1-armbru@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
GCC issues a false positive warning, resulting in build failure with -Werror:
In file included from /usr/include/glib-2.0/glib.h:114,
from src/include/glib-compat.h:32,
from src/include/qemu/osdep.h:144,
from ../src/hw/virtio/vhost-shadow-virtqueue.c:10:
In function ‘g_autoptr_cleanup_generic_gfree’,
inlined from ‘vhost_handle_guest_kick’ at ../src/hw/virtio/vhost-shadow-virtqueue.c:292:42:
/usr/include/glib-2.0/glib/glib-autocleanups.h:28:3: error: ‘elem’ may be used uninitialized [-Werror=maybe-uninitialized]
28 | g_free (*pp);
| ^~~~~~~~~~~~
../src/hw/virtio/vhost-shadow-virtqueue.c: In function ‘vhost_handle_guest_kick’:
../src/hw/virtio/vhost-shadow-virtqueue.c:292:42: note: ‘elem’ was declared here
292 | g_autofree VirtQueueElement *elem;
| ^~~~
cc1: all warnings being treated as errors
There is actually no problem since "elem" is initialized in both branches.
Silence the warning by initializig it with "NULL".
$ gcc --version
gcc (GCC) 12.2.0
Fixes: 9c2ab2f1ec ("vhost: stop transfer elem ownership in vhost_handle_guest_kick")
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20220910151117.6665-1-shentey@gmail.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
As the close-on-exec flags is not set on the file descriptors returned
by socketpair() at default, the fds will survive across exec' function.
In the case that exec' function get invoked, such as the live-update feature
which is been developing, it will cause fd leaks.
To address this problem, we should call qemu_socketpair() to create an pair of
connected sockets with the close-on-exec flag set.
Signed-off-by: Guoyi Tu <tugy@chinatelecom.cn>
Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <7002b12a5fb0a30cd878e14e07da61c36da72913.1661240709.git.tugy@chinatelecom.cn>
We can restore the device state in the destination via CVQ now. Remove
the migration blocker.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Since QEMU will be able to inject new elements on CVQ to restore the
state, we need not to depend on a VirtQueueElement to know if a new
element has been used by the device or not. Instead of check that, check
if there are new elements only using used idx on vhost_svq_flush.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
As discussed in previous series [1], this memory barrier is useless with
the atomic read of used idx at vhost_svq_more_used. Deleting it.
[1] https://lists.nongnu.org/archive/html/qemu-devel/2022-07/msg02616.html
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Since we're going to allow SVQ to add elements without the guest's
knowledge and without its own VirtQueueElement, it's easier to check if
an element is a valid head checking a different thing than the
VirtQueueElement.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
It was easier to allow vhost_svq_add to handle the memory. Now that we
will allow qemu to add elements to a SVQ without the guest's knowledge,
it's better to handle it in the caller.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reduce code duplication.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
We can unbind twice a file descriptor if we call twice
vhost_svq_set_svq_kick_fd because of this. Since it comes from vhost and
not from SVQ, that file descriptor could be a different thing that
guest's vhost notifier.
Likewise, it can happens the same if a guest start and stop the device
multiple times.
Reported-by: Lei Yang <leiyang@redhat.com>
Fixes: dff4426fa6 ("vhost: Add Shadow VirtQueue kick forwarding capabilities")
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Nothing actually reads the return value, but an error in cleaning some
entries could cause device stop to abort, making a restart impossible.
Better ignore explicitely the return value.
Reported-by: Lei Yang <leiyang@redhat.com>
Fixes: 34e3c94eda ("vdpa: Add custom IOTLB translations to SVQ")
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Although the device will be reset before usage, the right thing to do is
to clean it.
Reported-by: Lei Yang <leiyang@redhat.com>
Fixes: 34e3c94eda ("vdpa: Add custom IOTLB translations to SVQ")
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
It's convenient to call iova_tree_remove from a map returned from
iova_tree_find or iova_tree_find_iova. With the current code this is not
possible, since we will free it, and then we will try to search for it
again.
Fix it making accepting the map by value, forcing a copy of the
argument. Not applying a fixes tag, since there is no use like that at
the moment.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
If a map fails for whatever reason, it must not be saved in the tree.
Otherwise, qemu will try to unmap it in cleanup, leaving to more errors.
Fixes: 34e3c94eda ("vdpa: Add custom IOTLB translations to SVQ")
Reported-by: Lei Yang <leiyang@redhat.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Next patch will skip the registering of dma maps that the vdpa device
rejects in the iova tree. We need to consider that here or we cause a
SIGSEGV accessing result.
Reported-by: Lei Yang <leiyang@redhat.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
virtio level reset should not affect pci express
registers such as PM, error or link.
Fixes: 27ce0f3afc ("hw/virtio: fix Power Management Control Register for PCI Express virtio devices")
Fixes: d584f1b9ca ("hw/virtio: fix Link Control Register for PCI Express virtio devices")
Fixes: c2cabb3422 ("hw/virtio: fix error enabling flags in Device Control register")
Cc: "Marcel Apfelbaum" <marcel@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
As reads happen in the callback we were never seeing them. We only
really care about the header so move the tracepoint to when the header
is complete.
Fixes: 6ca6d8ee9d (hw/virtio: add vhost_user_[read|write] trace points)
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220728135503.1060062-5-alex.bennee@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The assert() protecting against leakage is a little aggressive and
causes needless crashes if a device is shutdown without having been
configured. In this case no descriptors are lost because none have
been assigned.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220728135503.1060062-4-alex.bennee@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
I've noticed asserts firing because we query the status of vdev after
a vhost connection is closed down. Rather than faulting on the NULL
indirect just quietly reply false.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220728135503.1060062-3-alex.bennee@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Currently we only enforce power-of-two mappings (required by the QEMU
notifier) for UNMAP requests. A MAP request not aligned on a
power-of-two may be successfully handled by VFIO, and then the
corresponding UNMAP notify will fail because it will attempt to split
that mapping. Ensure MAP and UNMAP notifications are consistent.
Fixes: dde3f08b5c ("virtio-iommu: Handle non power of 2 range invalidations")
Reported-by: Tina Zhang <tina.zhang@intel.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Message-Id: <20220718135636.338264-1-jean-philippe@linaro.org>
Tested-by: Tina Zhang <tina.zhang@intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
vhost_vdpa_listener_region_del is always deleting the first iova entry
of the tree, since it's using the needle iova instead of the result's
one.
This was detected using a vga virtual device in the VM using vdpa SVQ.
It makes some extra memory adding and deleting, so the wrong one was
mapped / unmapped. This was undetected before since all the memory was
mappend and unmapped totally without that device, but other conditions
could trigger it too:
* mem_region was with .iova = 0, .translated_addr = (correct GPA).
* iova_tree_find_iova returned right result, but does not update
mem_region.
* iova_tree_remove always removed region with .iova = 0. Right iova were
sent to the device.
* Next map will fill the first region with .iova = 0, causing a mapping
with the same iova and device complains, if the next action is a map.
* Next unmap will cause to try to unmap again iova = 0, causing the
device to complain that no region was mapped at iova = 0.
Fixes: 34e3c94eda ("vdpa: Add custom IOTLB translations to SVQ")
Reported-by: Lei Yang <leiyang@redhat.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
The SVQ vring used idx usually match with the guest visible one, as long
as all the guest buffers (GPA) maps to exactly one buffer within qemu's
VA. However, as we can see in virtqueue_map_desc, a single guest buffer
could map to many buffers in SVQ vring.
Also, its also a mistake to rewind them at the source of migration.
Since VirtQueue is able to migrate the inflight descriptors, its
responsability of the destination to perform the rewind just in case it
cannot report the inflight descriptors to the device.
This makes easier to migrate between backends or to recover them in
vhost devices that support set in flight descriptors.
Fixes: 6d0b222666 ("vdpa: Adapt vhost_vdpa_get_vring_base to SVQ")
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Since the vhost-vdpa device is exposing _F_LOG, adding a migration blocker if
it uses CVQ.
However, qemu is able to migrate simple devices with no CVQ as long as
they use SVQ. To allow it, add a placeholder error to vhost_vdpa, and
only add to vhost_dev when used. vhost_dev machinery place the migration
blocker if needed.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Do a simple forwarding of CVQ buffers, the same work SVQ could do but
through callbacks. No functional change intended.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Shadow CVQ will copy buffers on qemu VA, so we avoid TOCTOU attacks from
the guest that could set a different state in qemu device model and vdpa
device.
To do so, it needs to be able to map these new buffers to the device.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
This allows external handlers to be aware of new buffers that the guest
places in the virtqueue.
When this callback is defined the ownership of the guest's virtqueue
element is transferred to the callback. This means that if the user
wants to forward the descriptor it needs to manually inject it. The
callback is also free to process the command by itself and use the
element with svq_push.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
It allows the Shadow Control VirtQueue to wait for the device to use the
available buffers.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
This allows external parts of SVQ to forward custom buffers to the
device.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
This function allows external SVQ users to return guest's available
buffers.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
A guest's buffer continuos on GPA may need multiple descriptors on
qemu's VA, so SVQ should track its length sepparatedly.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
