The address that is passed from the guest should be treated as
untrusted. Currently an invalid address will panic the VMM. This only
allows the guest to hurt itself, but we shouldn't have the VMM crashing.
Instead let's return an error if possible or invalidate the queue if it
happen during setup.
The data flow from guest to translate_gva/translate_gpa is:
1. Guest writes a raw u64 address into a virtio descriptor in the
shared descriptor table (guest memory).
2. The virtio-queue crate reads this descriptor via read_obj() and
returns the addr field as-is in a GuestAddress — no validation.
3. Device code calls .translate_gva(access_platform, len) on the
GuestAddress.
4. With IOMMU (access_platform is Some): the address is an IOVA that
must be translated to a GPA via the IOMMU mapping table. If the
guest provides an unmapped IOVA, translation returns Err.
Previously, .unwrap() here panicked the VMM.
5. Without IOMMU (access_platform is None): translate_gva is a no-op
(returns self). The raw address flows to GuestMemory::read_obj()
which validates it — out-of-range addresses return
Err(InvalidGuestAddress), so no host memory corruption is possible.
Signed-off-by: Dylan Reid <dgreid@fb.com>
The unit test container runs with Docker default seccomp
profile which blocks io_uring_setup, io_uring_enter and
io_uring_register. This causes all qcow_async unit tests to
fail with EPERM when creating an io_uring instance.
Add --security-opt seccomp=unconfined to the unit test docker
run invocation. The container already has --device access and
cap_net_admin, so this does not materially change the security
posture.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Write a distinct byte pattern into each of eight consecutive
clusters in a single operation, then read the full range back
and verify per cluster contents.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Write data, punch hole to deallocate, then rewrite the same
range and verify the new contents read back correctly.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Add a QcowAsync unit test that writes 4K into the middle of a
cluster, then reads the entire cluster back. Verifies that the
written region matches and surrounding bytes remain zero. This
exercises the COW path where unwritten parts of a newly allocated
cluster must be zero filled.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Add a QcowAsync unit test that reads from a range that was never
written. Verifies the fundamental QCOW contract that unallocated
clusters return zeroes.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Add a QcowAsync unit test that submits a batch of interleaved
write and read requests via submit_batch_requests. Verifies that
all completions arrive with the correct user_data and that the
read back data matches the written data.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Add a QcowAsync unit test that writes distinct patterns into two
adjacent clusters, then issues a single read spanning the cluster
boundary. Verifies that multi mapping read resolution returns the
correct data from both clusters.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Add a QcowAsync unit test that writes a byte pattern through
write_vectored, reads it back through read_vectored, and verifies
the data matches. This exercises the core async write and read
paths end to end.
Also add an async_write helper for future tests.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Add a QcowAsync unit test for write zeroes completion. The test
verifies that a write zeroes request reports successful completion
and that the zeroed range reads back as zeroes.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Add a QcowAsync unit test for punch hole completion. The test
verifies that a punch hole request reports successful completion
and that the deallocated range reads back as zeroes.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Implement batch_requests_enabled() and submit_batch_requests() for
QcowAsync. Without batching, each read_vectored call performs its own
io_uring submit() syscall. With batching, the virtio queue handler
collects all pending requests and submits them in a single call,
pushing multiple SQEs before one submit() syscall.
Each request in the batch is classified through the metadata layer.
Requests that hit the fast path (single allocated cluster mapping)
are pushed to the io_uring submission queue. Requests that require
the slow path (compressed, backing, zero fill, or mixed mappings)
are completed synchronously and queued as synthetic completions.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
When io_uring is available and not disabled, open QCOW2 images
with QcowDiskAsync for asynchronous reads. Falls back to
QcowDiskSync otherwise.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
try_clone shares the Arc wrapped metadata and backing file.
new_async_io creates a QcowAsync worker with its own io_uring
instance for the given ring depth.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Deallocate clusters through QcowMetadata::deallocate_bytes, then
apply the resulting DeallocAction list (punch hole or write zeroes
at host offsets). write_zeroes delegates to punch_hole since
unallocated QCOW2 clusters inherently read as zero.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Flush dirty metadata caches and sync the underlying file via
QcowMetadata::flush, then signal synthetic completion.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Synchronous per cluster write path - gather guest data from iovecs,
map each cluster through QcowMetadata, and pwrite to the allocated
host offset. Partial cluster writes with a backing file read the
backing data first so map_cluster_for_write can perform COW.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Single allocated cluster reads are submitted to io_uring for true
async completion. Mixed mapping reads (zero, compressed, backing,
multi cluster) fall back to synchronous pread64 with synthetic
completions.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Add the AsyncIo trait impl with notifier and next_completed_request
filled in. The remaining methods are stubbed with unimplemented
and will be filled in by subsequent commits.
next_completed_request drains io_uring completions first, then
falls back to the synthetic completion list.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Per queue I/O worker that uses io_uring for asynchronous reads
against fully allocated clusters. The struct holds the shared
metadata, data file, optional backing reader, the io_uring
instance and a synthetic completion list.
Feature gated on io_uring in lib.rs.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Marker supertrait combining all composable capability traits.
QcowDiskAsync now satisfies the full DiskFile contract.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Delegates to QcowMetadata::resize. Rejects resize when a backing
file is present, same as the sync backend.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Introduce the device level handle for the async QCOW2 backend.
QcowDiskAsync mirrors QcowDiskSync. It parses the image, resolves
the backing chain and wraps QcowMetadata in an Arc for sharing
across virtio queues. No trait impls yet, just the struct,
constructor, Drop and Debug.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Move the backing file constructor into qcow/backing alongside the
types it creates. Both qcow_sync and qcow_async can now import
shared_backing_from directly from qcow/backing.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Move the raw backing file reader into the new qcow/backing module
so it can be shared between qcow_sync and the upcoming qcow_async
backend.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Move scatter_to_iovecs, zero_fill_iovecs and gather_from_iovecs into
qcow_common so they can be shared with the upcoming qcow_async backend.
These helpers treat an iovec array as a flat byte stream and are used by
both read_vectored and write_vectored code paths.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
These position independent I/O helpers use pread64/pwrite64 to avoid
races on the shared file position when multiple queues operate on
duplicated file descriptors. Extracting them prepares for reuse by
the upcoming qcow_async backend.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
The updated image is configured in a same way as the
previously used 2022.
SAC, SSH, and RDP are configured.
All Windows updates to the curent date are installed.
Includes latest stable virtio-win 0.1.285 drivers.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
After memory hotplug, it may happen that it takes a few seconds until a
VFIO device is available again (IOMMU/DMA mappings need update).
On-behalf-of: SAP philipp.schuster@sap.com
Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
This struct has the same members and it can be reused to reduce
complexity now and if other common PCI related fields need to be
added in the future.
Signed-off-by: Rob Bradford <rbradford@meta.com>
This can then be used with the OptionParser::add_all() API to reduce the
number of locations the same options are added to the parser. The only
quirk is that some devices do not support an IOMMU (because they are
vhost-user / vfio-user based). There are two different versions of the
array to support that.
Signed-off-by: Rob Bradford <rbradford@meta.com>
The IommuNotSupportedOnSegment variant is no longer needed as the common
PciDeviceCommonConfig::validate() handles this case with the
OnIommuSegment variant along with more use of the IommuNotSupported
error variant.
Signed-off-by: Rob Bradford <rbradford@meta.com>
Switch VsockConfig over to using the newly extracted struct members as
used by all PCI based devices. The use of #[serde(flatten)] means that
this change has no impact on the JSON format that the data is stored as.
Signed-off-by: Rob Bradford <rbradford@meta.com>
Switch VdpaConfig over to using the newly extracted struct members as
used by all PCI based devices. The use of #[serde(flatten)] means that
this change has no impact on the JSON format that the data is stored as.
Signed-off-by: Rob Bradford <rbradford@meta.com>
Switch UserDeviceConfig over to using the newly extracted struct members
as used by all PCI based devices. The use of #[serde(flatten)] means
that this change has no impact on the JSON format that the data is
stored as.
As VFIO user devices do not support being placed behind an IOMMU an
error is now raised if iommu is set. This can't happen via the CLI but
could via the JSON/API.
Signed-off-by: Rob Bradford <rbradford@meta.com>
Switch DeviceConfig over to using the newly extracted struct members as
used by all PCI based devices. The use of #[serde(flatten)] means that
this change has no impact on the JSON format that the data is stored as.
Signed-off-by: Rob Bradford <rbradford@meta.com>
Switch PmemConfig over to using the newly extracted struct members as
used by all PCI based devices. The use of #[serde(flatten)] means that
this change has no impact on the JSON format that the data is stored as.
Signed-off-by: Rob Bradford <rbradford@meta.com>
Switch GenericVhostUserConfig over to using the newly extracted struct
members as used by all PCI based devices. The use of #[serde(flatten)]
means that this change has no impact on the JSON format that the data is
stored as.
As generic vhost-user devices do not support being placed behind an
IOMMU an error is now raised if iommu is set. This can't happen via the
CLI but could via the JSON/API.
Signed-off-by: Rob Bradford <rbradford@meta.com>
Switch FsConfig over to using the newly extracted struct members as used
by all PCI based devices. The use of #[serde(flatten)] means that this
change has no impact on the JSON format that the data is stored as.
As virtio-fs does not support being placed behind an IOMMU an error is
now raised if iommu is set. This option is not exposed via the CLI but
could happen with a miscontructed JSON/API call.
Signed-off-by: Rob Bradford <rbradford@meta.com>
Switch NetConfig over to using the newly extracted struct members as
used by all PCI based devices. The use of #[serde(flatten)] means that
this change has no impact on the JSON format that the data is stored as.
Signed-off-by: Rob Bradford <rbradford@meta.com>
