Commit Graph

36 Commits

Author SHA1 Message Date
Dylan Reid
1b2326fde4 block: Remove legacy async I/O API
Drop the borrowed iovec AsyncIo entry points now that all callers use
owned operations. Rename the transitional owned batch and completion
methods to the final trait names and remove the borrowed submission
helpers from the queue wrappers.

This removes a bunch of known safety foot-guns so future-us don't
accidentally use them.

Assisted-by: Codex:GPT-5.5
Signed-off-by: Dylan Reid <dgreid@fb.com>
2026-05-27 12:07:03 +00:00
Dylan Reid
9143039805 block: Add owned raw Linux AIO path
Start using AioDataIo from RawFileAsyncAio. This adds a temporary
submit_borrowed_operation to enable preserving the unsafe iovec api
until we can remove it in the forthcoming commits.

Signed-off-by: Dylan Reid <dgreid@fb.com>
2026-05-27 12:07:03 +00:00
Wei Liu
2fe775fce2 block: use BLKDISCARD/BLKZEROOUT ioctls for block devices
Some block devices (ZFS volume) may require BLKDISCARD and BLKZEROOUT
ioctls for discard and write_zeroes operations respectively.

There is no good way to probe whether fallocate is supported on a block
device. Arguably, punch_hole and write_zeroes are rare. Instead of
having a complex scheme for the IO uring backend, we force it to always
use ioctls. The code can be changed if the synchronized ioctls become a
performance issue.

Changes:
- Detect block devices at construction time
- Use BLKDISCARD ioctl for punch_hole (discard) on block devices
- Use BLKZEROOUT ioctl for write_zeroes on block devices
- Add BLKDISCARD/BLKZEROOUT to VirtioBlock seccomp whitelist
- Keep fallocate() path for regular files (no behavior change)
- Consolidate some helper functions to the new sparse module

Signed-off-by: Wei Liu <liuwe@microsoft.com>
2026-05-14 22:35:02 +00:00
Anatol Belski
701767e5be block: Use RawDisk in factory, remove old wrappers
Update open_raw to construct RawDisk instead of choosing between
RawFileDisk, RawFileDiskSync and RawFileDiskAio. The backend decision
is now made inside RawDisk::create_async_io.

Remove the DiskFile wrapper structs from raw_sync.rs, raw_async.rs
and raw_async_aio.rs. Only the AsyncIo worker structs remain in those
files. Reduce their module visibility to pub(crate).

Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
2026-04-23 20:15:49 +00:00
Anatol Belski
21cd13df01 block: Rename AsyncDiskFile::new_async_io to create_async_io
The new_ prefix in Rust conventionally denotes constructors that return
Self (e.g. Vec::new(), File::new()). AsyncDiskFile::new_async_io does
not return Self. It is a factory method that constructs and returns a
Box<dyn AsyncIo> worker bound to the disk file descriptor and
metadata. The create_ prefix communicates this: the caller receives
a freshly constructed object of a different type.

This rename touches every format backend in block plus two external
callers in virtio-devices and performance-metrics. Every change is a
mechanical s/new_async_io/create_async_io/ substitution. No functional
change.

Ref: #7877 (task 3.2.8)
Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
2026-04-21 10:36:52 +00:00
Muminul Islam
f6b4061629 block: Return BlockResult from RawFileAsyncAio::new()
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>
2026-04-02 01:18:30 +00:00
Muminul Islam
783cc8bbd9 block: Remove legacy DiskFile impl from RawFileDiskAio
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>
2026-04-02 01:18:30 +00:00
Muminul Islam
6df7cda4ad block: Implement AsyncDiskFile trait for RawFileDiskAio
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>
2026-04-02 01:18:30 +00:00
Muminul Islam
39bbbaaa59 block: Implement DiskFile marker trait for RawFileDiskAio
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>
2026-04-02 01:18:30 +00:00
Muminul Islam
62264cb3c7 block: Implement Resizable trait for RawFileDiskAio
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>
2026-04-02 01:18:30 +00:00
Muminul Islam
b7cf8737ac block: Implement SparseCapable trait for RawFileDiskAio
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>
2026-04-02 01:18:30 +00:00
Muminul Islam
190380c9ba block: Implement Geometry trait for RawFileDiskAio
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>
2026-04-02 01:18:30 +00:00
Muminul Islam
df890599c2 block: Implement DiskFd trait for RawFileDiskAio
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>
2026-04-02 01:18:30 +00:00
Muminul Islam
78bbdbef86 block: Implement PhysicalSize trait for RawFileDiskAio
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>
2026-04-02 01:18:30 +00:00
Muminul Islam
fca54cb142 block: Implement DiskSize trait for RawFileDiskAio
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>
2026-04-02 01:18:30 +00:00
Muminul Islam
98dbe6d128 block: Derive Debug on RawFileDiskAio
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>
2026-04-02 01:18:30 +00:00
Anatol Belski
1b92af5534 block: raw_async_aio: Use query_device_size() for size queries
Use query_device_size() instead of seek(End(0)) and metadata().len()
to correctly handle block device and regular file handles.

Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
2026-03-27 11:05:07 +00:00
Anatol Belski
19fa512f02 block: Batch drain AIO completions in next_completed_request
Collect up to 32 completions per io_getevents call instead of one
at a time, buffering them in the existing VecDeque. This reduces
syscalls from 128 to 4 per drain cycle at the default queue depth.
The stack cost is 1 KB per call.

Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
2026-03-19 12:20:19 +00:00
Anatol Belski
1733e08a0f block: raw: Replace FALLOC_FL_* consts with libc::* in raw backends
raw_sync, raw_async, and raw_async_aio each defined
FALLOC_FL_PUNCH_HOLE, FALLOC_FL_KEEP_SIZE, and FALLOC_FL_ZERO_RANGE as
local constants in their punch_hole() and write_zeroes()
implementations. These are available from the libc crate directly.

Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
2026-03-14 14:00:29 +00:00
Anatol Belski
d883b54fb7 block: Deduplicate raw_sync and raw_async_aio tests
Replace duplicated test bodies with thin wrappers that construct
the backend-specific AsyncIo instance and delegate to the shared
raw_async_io_tests helpers.

Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
2026-03-14 13:39:41 +00:00
Emir Beganovic
623af62743 block: Implement write_zeroes and punch_hole for AIO backend
The AIO block backend advertises VIRTIO_BLK_F_WRITE_ZEROES
and VIRTIO_BLK_F_DISCARD to guests because the filesystem
probe (supports_sparse_operations) returns true on ext4/XFS.
However, RawFileAsyncAio::write_zeroes() and punch_hole()
return errors because Linux AIO (io_submit) has no IOCB
command for fallocate.

When io_uring is unavailable (e.g. io_uring_disabled=2, a
common security hardening on enterprise Linux), Cloud
Hypervisor falls back to the AIO backend. The guest
negotiates the feature, issues WRITE_ZEROES requests, and
gets I/O errors.

Implement write_zeroes and punch_hole using synchronous
libc::fallocate() calls, matching the pattern used by the
sync backend (RawFileSync). A VecDeque-based completion
list signals results to the caller via the existing eventfd
mechanism.

Unit tests mirror the existing raw_sync.rs test suite.
Integration tests add AIO-specific variants of the discard
and fstrim tests using _disable_io_uring=on.

Signed-off-by: Emir Beganovic <beganovic.emir@gmail.com>
2026-03-12 12:08:01 +00:00
Anatol Belski
b7b38df99c block: raw: Use map_or instead of map().unwrap_or()
Do the necessary replacements to satisfy clippy::map_unwrap_or.

Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
2026-03-06 12:32:38 +00:00
Saravanan D
00c05f4761 block: Use logical block size for alignment
O_DIRECT requires buffer addresses to be aligned to the backend
device's logical block size. The existing bounce buffer logic in
execute_async() hardcodes SECTOR_SIZE (512) for the alignment check
and bounce buffer allocation. This is insufficient for devices with
a 4096-byte logical block size, where misaligned buffers cause
-EINVAL from the host kernel.

Add an alignment() method to the AsyncIo trait that returns the
backend's logical block size, defaulting to SECTOR_SIZE. The three
raw I/O backends (io_uring, AIO, synchronous) probe the device
topology via DiskTopology::probe() at creation time and return the
actual logical block size. All image format backends would simply
use the default value of 512 bytes since their underlying are
not block devices.

execute_async() now queries disk_image.alignment() instead of using
the hardcoded SECTOR_SIZE

Fixes: #7720

Signed-off-by: Saravanan D <saravanand@crusoe.ai>
2026-02-26 15:47:17 +00:00
Anatol Belski
7f4b56b217 block: Add sparse operations capability query
Add capability query to DiskFile trait to check backend
support for sparse operations (punch hole, write zeroes,
discard). Only advertise VIRTIO_BLK_F_DISCARD and
VIRTIO_BLK_F_WRITE_ZEROES when the backend supports these
operations.

Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
2026-02-13 18:44:30 +00:00
Anatol Belski
7095605d84 block: Add punch_hole and write_zeroes to AsyncIo trait
Add punch_hole() and write_zeroes() methods to the AsyncIo trait
with stub implementations for all backends. These will be used to
support DISCARD and WRITE_ZEROES operations.

Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com>
2026-02-13 18:44:30 +00:00
Philipp Schuster
603b5e862c block: add DiskFile::physical_size()
This is a pre-requisite for the bug fix in the following commit.

Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
On-behalf-of: SAP philipp.schuster@sap.com
2025-12-14 17:02:36 +00:00
Philipp Schuster
53092359b4 block: rename DiskFile::size() -> DiskFile::logical_size()
This better reflects the actual usage.

Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
On-behalf-of: SAP philipp.schuster@sap.com
2025-12-14 17:02:36 +00:00
Philipp Schuster
5f66a26b2e misc: block: drop extern crate, use modern rust
This commit is part of a series of similar commits.

Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
On-behalf-of: SAP philipp.schuster@sap.com
2025-11-24 22:36:46 +00:00
Philipp Schuster
363273111a build: treewide: fmt for edition 2024
`cargo +nightly fmt`

Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
On-behalf-of: SAP philipp.schuster@sap.com
2025-09-10 18:35:38 +00:00
Jinank Jain
2bc8d51a60 misc: Fix missing lifetime syntax clippy warning
This was caught by the nightly compiler during cargo fuzz build.

error: lifetime flowing from input to output with different syntax can be confusing
   --> /home/runner/work/cloud-hypervisor/cloud-hypervisor/hypervisor/src/arch/x86/emulator/mod.rs:493:26
    |
493 |     pub fn new(platform: &mut dyn PlatformEmulator<CpuState = T>) -> Emulator<T> {
    |                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^     ----------- the lifetime gets resolved as `'_`
    |                          |
    |                          this lifetime flows to the output
    |
    = note: `-D mismatched-lifetime-syntaxes` implied by `-D warnings`
    = help: to override `-D warnings` add `#[allow(mismatched_lifetime_syntaxes)]`
help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
    |
493 |     pub fn new(platform: &mut dyn PlatformEmulator<CpuState = T>) -> Emulator<'_, T> {

Signed-off-by: Jinank Jain <jinankjain@microsoft.com>
2025-06-09 11:19:11 +00:00
Philipp Schuster
2da5e10689 block: bind FD lifetime of DiskFile
As we can't use BorrowedFd, we should at least create a similar
safe alternative.

Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
On-behalf-of: SAP philipp.schuster@sap.com
2025-05-16 08:07:32 +00:00
Philipp Schuster
a647d7863c block: enable to get a raw FD of each block device's DiskFile
This is a prerequisite for the next steps.

Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
On-behalf-of: SAP philipp.schuster@sap.com
2025-05-16 08:07:32 +00:00
Rob Bradford
88a9f79944 misc: Adapt consistent import style formatting
Historically the Cloud Hypervisor coding style has been to ensure that
all imports are ordered and placed in a single group. Unfortunately
cargo fmt has no support for ensuring that all imports are in a single
group so if whitespace lines were added as part of the import statements
then they would only be odered correctly in the group.

By adopting "group_imports="StdExternalCrate" we can enforce a style
where imports are placed in at most three groups for std, external
crates and the crate itself. Choosing a style enforceable by the tooling
reduces the reviewer burden.

Signed-off-by: Rob Bradford <rbradford@rivosinc.com>
2024-09-29 13:08:12 +01:00
Thomas Barrett
d9ed281719 block: fix aio backend behavior when writeback enabled
Signed-off-by: Thomas Barrett <tbarrett@crusoeenergy.com>
2023-11-08 19:24:40 -08:00
Thomas Barrett
4980a5f778 block: add copyright text to raw_async_aio.rs
Signed-off-by: Thomas Barrett <tbarrett@crusoeenergy.com>
2023-10-30 12:34:23 -07:00
Thomas Barrett
bae13c5c56 block: add aio disk backend
Signed-off-by: Thomas Barrett <tbarrett@crusoeenergy.com>
2023-10-25 10:19:23 -07:00