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>
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>
Change the return type of RawFileAsyncAio::new() from
std::io::Result<Self> to BlockResult<Self>, wrapping
internal errors from EventFd::new() and IoContext::new()
in BlockError with DiskFileError::NewAsyncIo.
This simplifies the caller in AsyncDiskFile::new_async_io()
which no longer needs its own error mapping.
Signed-off-by: Muminul Islam <muislam@microsoft.com>
Remove the old async_io::DiskFile trait implementation from
RawFileDiskAio, now that the new disk_file trait hierarchy
is fully implemented.
Clean up unused imports: DiskFile and DiskFileResult from
crate::async_io.
Signed-off-by: Muminul Islam <muislam@microsoft.com>
Add disk_file::AsyncDiskFile trait implementation for
RawFileDiskAio with try_clone() and new_async_io() methods.
try_clone() duplicates the underlying file descriptor and
wraps it in a new RawFileDiskAio. new_async_io() creates a
RawFileAsyncAio (Linux AIO) backend, wrapping errors in
BlockError instead of DiskFileError.
Signed-off-by: Muminul Islam <muislam@microsoft.com>
Add empty disk_file::DiskFile impl for RawFileDiskAio.
This marker supertrait requires DiskSize + Geometry + Sync,
all of which are now satisfied.
Signed-off-by: Muminul Islam <muislam@microsoft.com>
Add disk_file::Resizable trait implementation for
RawFileDiskAio. Calls file.set_len(size) and wraps the
I/O error in BlockError on failure.
Signed-off-by: Muminul Islam <muislam@microsoft.com>
Add disk_file::SparseCapable trait implementation for
RawFileDiskAio. Delegates to probe_sparse_support() to
detect whether the underlying file supports hole-punching.
Signed-off-by: Muminul Islam <muislam@microsoft.com>
Add disk_file::Geometry trait implementation for
RawFileDiskAio. Probes disk topology from the file,
falling back to defaults on failure. Takes &self instead
of &mut self and uses unwrap_or_else for cleaner error
handling.
Signed-off-by: Muminul Islam <muislam@microsoft.com>
Add disk_file::DiskFd trait implementation for
RawFileDiskAio. Delegates to file.as_raw_fd() via
BorrowedDiskFd, taking &self instead of &mut self.
Signed-off-by: Muminul Islam <muislam@microsoft.com>
Add disk_file::PhysicalSize trait implementation for
RawFileDiskAio. Returns the physical size from
query_device_size wrapped in BlockError on failure,
consistent with the DiskSize impl.
Signed-off-by: Muminul Islam <muislam@microsoft.com>
Add disk_file::DiskSize trait implementation for
RawFileDiskAio using BlockError and BlockResult. Takes
&self instead of &mut self.
Add BlockError, BlockErrorKind, BlockResult, and disk_file
imports needed by this and subsequent trait impls.
Signed-off-by: Muminul Islam <muislam@microsoft.com>
Add #[derive(Debug)] to RawFileDiskAio. This is required
by the new disk_file traits which have Send + Debug bounds.
Signed-off-by: Muminul Islam <muislam@microsoft.com>
Introduce ExecuteError::UnsupportedFlags to carry both the
request type and the rejected flags value, replacing the
generic ExecuteError::Unsupported at discard and write zeroes
flag validation sites. This provides structured context for
debugging without changing the returned VIRTIO_BLK_S_UNSUPP
status.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
The virtio spec v1.2 in 5.2.6.2 requires that the device
MUST return VIRTIO_BLK_S_UNSUPP for write zeroes commands
if any unknown flag is set.
Add an early check that rejects requests with reserved flag
bits set by returning VIRTIO_BLK_S_UNSUPP via the existing
ExecuteError::Unsupported variant.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
The virtio spec v1.2 in 5.2.6.2 requires that the device
MUST return VIRTIO_BLK_S_UNSUPP for discard commands if the
unmap flag is set or if any unknown flag is set.
The discard handler was not reading the flags field at all,
silently accepting requests with arbitrary flags. Read and
validate the flags, rejecting any non-zero value with
VIRTIO_BLK_S_UNSUPP.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Delegate try_clone() to FixedVhd::clone() and new_async_io() to
FixedVhdSync, preserving DiskFileError::NewAsyncIo.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Delegate to FixedVhd::physical_size() which calls file.metadata().
Preserve the crate::Error::GetFileMetadata variant as the BlockError
source for diagnostic chain traversal.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Delegate to FixedVhd::logical_size() which returns the guest
visible capacity parsed from the VHD footer at construction.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
Classify the io::Error as BlockErrorKind::Io with ErrorOp::Open.
Update vmm CreateFixedVhdDiskSync to take BlockError.
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
