Commit Graph

276 Commits

Author SHA1 Message Date
Manos Pitsidianakis
f63000d943 rust/pl011: merge device_class.rs into device.rs
The split was a relic of early development and is not necessary.

Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Link: https://lore.kernel.org/r/20250718-rust-pl011-cleanup-v1-1-c71b1d6a69a5@linaro.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-07-22 12:49:51 +02:00
Paolo Bonzini
0d70c5aa1b rust: devices are not staticlibs
This is only cosmetic for now, but hopefully later on Meson will parse more
of Cargo.toml.  Devices are linked into a staticlib but are not staticlibs
themselves.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-07-22 12:49:51 +02:00
Stefan Hajnoczi
e452053097 virtio,pci,pc: features, fixes, tests
SPCR acpi table can now be disabled
 vhost-vdpa can now report hashing capability to guest
 PPTT acpi table now tells guest vCPUs are identical
 vost-user-blk now shuts down faster
 loongarch64 now supports bios-tables-test
 intel_iommu now supports ATS
 cxl now supports DCD Fabric Management Command Set
 arm now supports acpi pci hotplug
 
 fixes, cleanups
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_upstream' of https://git.kernel.org/pub/scm/virt/kvm/mst/qemu into staging

virtio,pci,pc: features, fixes, tests

SPCR acpi table can now be disabled
vhost-vdpa can now report hashing capability to guest
PPTT acpi table now tells guest vCPUs are identical
vost-user-blk now shuts down faster
loongarch64 now supports bios-tables-test
intel_iommu now supports ATS
cxl now supports DCD Fabric Management Command Set
arm now supports acpi pci hotplug

fixes, cleanups

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

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* tag 'for_upstream' of https://git.kernel.org/pub/scm/virt/kvm/mst/qemu: (97 commits)
  hw/cxl: mailbox-utils: 0x5605 - FMAPI Initiate DC Release
  hw/cxl: mailbox-utils: 0x5604 - FMAPI Initiate DC Add
  hw/cxl: Create helper function to create DC Event Records from extents
  hw/cxl: mailbox-utils: 0x5603 - FMAPI Get DC Region Extent Lists
  hw/cxl: mailbox-utils: 0x5602 - FMAPI Set DC Region Config
  hw/mem: cxl_type3: Add DC Region bitmap lock
  hw/cxl: Move definition for dynamic_capacity_uuid and enum for DC event types to header
  hw/cxl: mailbox-utils: 0x5601 - FMAPI Get Host Region Config
  hw/mem: cxl_type3: Add dsmas_flags to CXLDCRegion struct
  hw/cxl: mailbox-utils: 0x5600 - FMAPI Get DCD Info
  hw/cxl: fix DC extent capacity tracking
  tests: virt: Update expected ACPI tables for virt test
  hw/acpi/aml-build: Build a root node in the PPTT table
  hw/acpi/aml-build: Set identical implementation flag for PPTT processor nodes
  tests: virt: Allow changes to PPTT test table
  qtest/bios-tables-test: Generate reference blob for DSDT.acpipcihp
  qtest/bios-tables-test: Generate reference blob for DSDT.hpoffacpiindex
  tests/qtest/bios-tables-test: Add aarch64 ACPI PCI hotplug test
  tests/qtest/bios-tables-test: Prepare for addition of acpi pci hp tests
  hw/arm/virt: Let virt support pci hotplug/unplug GED event
  ...

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Conflicts:
  net/vhost-vdpa.c
  vhost_vdpa_set_steering_ebpf() was removed, resolve the context
  conflict.
2025-07-16 07:00:47 -04:00
Michael S. Tsirkin
4bf06bcf07 rust: bindings: allow any number of params
We are going to be adding more parameters, and this makes
rust unhappy:
    Functions with lots of parameters are considered bad style and reduce
    readability (“what does the 5th parameter mean?”). Consider grouping
    some parameters into a new type.

Specifically:

error: this function has too many arguments (8/7)
    --> /builds/mstredhat/qemu/build/rust/qemu-api/rust-qemu-api-tests.p/structured/bindings.inc.rs:3840:5
     |
3840 | /     pub fn new_bitfield_1(
3841 | |         secure: std::os::raw::c_uint,
3842 | |         space: std::os::raw::c_uint,
3843 | |         user: std::os::raw::c_uint,
...    |
3848 | |         address_type: std::os::raw::c_uint,
3849 | |     ) -> __BindgenBitfieldUnit<[u8; 4usize]> {
     | |____________________________________________^
     |
     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#too_many_arguments
     = note: `-D clippy::too-many-arguments` implied by `-D warnings`
     = help: to override `-D warnings` add `#[allow(clippy::too_many_arguments)]`

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <e41344bd22248b0883752ef7a7c459090a3d9cfc.1752560127.git.mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2025-07-15 02:56:39 -04:00
Paolo Bonzini
ed7f6da282 rust/qemu-api: log: implement io::Write
This makes it possible to lock the log file; it also makes log_mask_ln!
not allocate memory when logging a constant string.

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-07-10 18:33:51 +02:00
Manos Pitsidianakis
a721d9a9f3 rust/qemu-api-macros: add unit tests
Add unit tests to check Derive macro output for expected error messages,
or for expected correct codegen output.

Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20250704-rust_add_derive_macro_unit_tests-v1-2-ebd47fa7f78f@linaro.org
[Remove usage of MacroError. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-07-10 18:33:51 +02:00
Manos Pitsidianakis
c3a08c8dcb rust/qemu-api-macros: normalize TryInto output
Remove extraneous `;` and add missing trailing comma to TryInto derive
macro to match rustfmt style. We will add a test in the followup commit
and we would like the inlined output in the test body to be properly
formatted as well.

No functional changes intended.

Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20250704-rust_add_derive_macro_unit_tests-v1-1-ebd47fa7f78f@linaro.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-07-10 18:33:51 +02:00
Manos Pitsidianakis
dab63b8a71 rust/bindings: allow unnecessary_transmutes (1.88)
This is a new lint introduced in Rust 1.88. It does not affect
compilation when using a previous version or our MSRV, 1.77. But with
1.88 compilation fails because we deny all warnings:

  error: unnecessary transmute
     --> rust/qemu-api/libqemu_api.rlib.p/structured/bindings.inc.rs:729:18
      |
  729 |         unsafe { ::std::mem::transmute(self._bitfield_1.get(0usize, 24u8) as u32) }
      |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace this with: `u32::cast_signed(self._bitfield_1.get(0usize, 24u8) as u32)`
      |
      = note: `-D unnecessary-transmutes` implied by `-D warnings`
      = help: to override `-D warnings` add `#[allow(unnecessary_transmutes)]`

Allow this lint, which even though it does not exist in previous
versions, it works because we allow for `unknown_lints` in
rust/Cargo.toml.

Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Link: https://lore.kernel.org/r/20250703-rust_bindings_allow_unnecessary_transmutes-v1-1-692ca210d331@linaro.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-07-10 18:33:51 +02:00
Manos Pitsidianakis
caa08d30f2 rust/qemu-api-macros: use syn::Error directly
Our MacroError type wraps syn::Error as a variant, and uses another
variant for custom errors. Fortunately syn::Error can be used directly,
avoiding extra code on our side, so change the proc macro crate to use
it.

Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Link: https://lore.kernel.org/r/20250703-rust_macros-v1-1-b99f82febbbf@linaro.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-07-10 18:33:51 +02:00
Zhao Liu
bffbb430ee rust/qemu-api: Fix binding path in source directory
The build.rs had supported placing bindings.inc.rs in rust/qemu-api/src,
but this "not encouraged" feature is broken.

Considering that manually copying bindings.inc.rs to the development
directory is also useful, fix the bindings.inc.rs path generation to
give this feature another chance.

Fixes: commit 1ae4ca0463 ("rust: move rust.bindgen to qemu-api crate")
Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20250623073436.1833357-1-zhao1.liu@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-07-10 18:33:51 +02:00
Paolo Bonzini
6b3fad084f rust: hpet: fix new warning
Nightly rustc complains that HPETAddrDecode has a lifetime but it is not
clearly noted that it comes from &self.  Apply the compiler's suggestion
to shut it up.

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-20 13:25:59 +02:00
Bernhard Beschow
b783601d1a rust: pl011: Add missing logging to match C version
Co-developed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Link: https://lore.kernel.org/r/20250615112037.11992-4-shentey@gmail.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-20 13:25:59 +02:00
Bernhard Beschow
1563f287dc rust: pl011: Implement logging
Now that there is logging support in Rust for QEMU, use it in the pl011
device.

Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Link: https://lore.kernel.org/r/20250615112037.11992-3-shentey@gmail.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-20 13:25:59 +02:00
Bernhard Beschow
ab81002252 rust/qemu-api: Add initial logging support based on C API
A log_mask_ln!() macro is provided which expects similar arguments as the
C version. However, the formatting works as one would expect from Rust.

To maximize code reuse the macro is just a thin wrapper around
qemu_log(). Also, just the bare minimum of logging masks is provided
which should suffice for the current use case of Rust in QEMU.

Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Link: https://lore.kernel.org/r/20250615112037.11992-2-shentey@gmail.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-20 13:25:59 +02:00
Paolo Bonzini
1ae4ca0463 rust: move rust.bindgen to qemu-api crate
Once qemu-api is split in multiple crates, each of them will have
its own invocation of bindgen.  There cannot be only one, because
there are occasional "impl" blocks for the bindgen-generated
structs (e.g. VMStateFlags or QOM classes) that have to
reside in the same crate as the bindgen-generated code.

For now, prepare for this new organization by invoking bindgen
within the qemu-api crate's build definitions; it's also a
much better place to list enums that need specific treatment
from bindgen.

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-20 13:24:42 +02:00
Paolo Bonzini
1548c5cdf0 rust: prepare variable definitions for multiple bindgen invocations
When splitting the QEMU Rust bindings into multiple crates, the
bindgen-generated structs also have to be split so that it's
possible to add "impl" blocks (e.g. for Sync/Send or Default,
or even for utility methods in cases such as VMStateFlags).

Tweak various variable definitions in meson.build, to avoid naming
conflicts once there will be multiple bindgen invocations.

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-20 13:24:25 +02:00
Paolo Bonzini
345bef46a1 rust: qom: change instance_init to take a ParentInit<>
This removes undefined behavior associated to writing to uninitialized
fields, and makes it possible to remove "unsafe" from the instance_init
implementation.

However, the init function itself is still unsafe, because it must promise
(as a sort as MaybeUninit::assume_init) that all fields have been
initialized.

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-17 09:54:52 +02:00
Paolo Bonzini
8d394f6cf0 rust: qom: make ParentInit lifetime-invariant
This is the trick that allows the parent-field initializer to be used
only for the object that it's meant to be initialized.  This way,
the owner of a MemoryRegion must be the object that embeds it.

More information is in the comments; it's best explained with a simplified
example.

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-17 09:54:52 +02:00
Paolo Bonzini
a441222583 rust: qom: introduce ParentInit
This is a smart pointer for MaybeUninit; it can be upcasted to the
already-initialized parent classes, or dereferenced to a MaybeUninit
for the class that is being initialized.

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-17 09:54:52 +02:00
Paolo Bonzini
eb64a0c6ae rust: hpet: fully initialize object during instance_init
The array of BqlRefCell<HPETTimer> is not initialized yet at the
end of instance_init.  In particular, the "state" field is NonNull
and therefore it is invalid to have it as zero bytes.

Note that MaybeUninit is necessary because assigning to self.timers[index]
would trigger Drop of the old value.

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-17 09:54:51 +02:00
Paolo Bonzini
abf1832424 rust: qemu_api: introduce MaybeUninit field projection
Add a macro that makes it possible to convert a MaybeUninit<> into
another MaybeUninit<> for a single field within it.  Furthermore, it is
possible to use the resulting MaybeUninitField<> in APIs that take the
parent object, such as memory_region_init_io().

This allows removing some of the undefined behavior from instance_init()
functions, though this may not be the definitive implementation.

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-17 09:54:51 +02:00
Paolo Bonzini
bc2a48d647 rust: make TryFrom macro more resilient
If the enum includes values such as "Ok", "Err", or "Error", the TryInto
macro can cause errors.  Be careful and qualify identifiers with the full
path, or in the case of TryFrom<>::Error do not use the associated type
at all.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-06 14:32:54 +02:00
Zhao Liu
869b0afa4f rust/hpet: Drop BqlCell wrapper for num_timers
Now that the num_timers field is initialized as a property, someone may
change its default value using qdev_prop_set_uint8(), but the value is
fixed after the Rust code sees it first.  Since there is no need to modify
it after realize(), it is not to be necessary to have a BqlCell wrapper.

Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20250520152750.2542612-4-zhao1.liu@intel.com
[Remove .into() as well. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-06 14:32:54 +02:00
Paolo Bonzini
4d2fec89cb rust/hpet: return errors from realize if properties are incorrect
Match the code in hpet.c; this also allows removing the
BqlCell from the num_timers field.

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-06 14:32:54 +02:00
Paolo Bonzini
b3bf86b893 rust/hpet: change type of num_timers to usize
Remove the need to convert after every read of the BqlCell.  Because the
vmstate uses a u8 as the size of the VARRAY, this requires switching
the VARRAY to use num_timers_save; which in turn requires ensuring that
the num_timers_save is always there.  For simplicity do this by
removing support for version 1, which QEMU has not been producing for
~15 years.

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-06 14:32:54 +02:00
Paolo Bonzini
4b66abead9 rust: qdev: support returning errors from realize
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-06 14:32:53 +02:00
Paolo Bonzini
9a33f49f44 rust: qemu-api: add tests for Error bindings
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-05 20:24:51 +02:00
Paolo Bonzini
b4ff3cf34f rust: qemu-api: add bindings to Error
Provide an implementation of std::error::Error that bridges the Rust
anyhow::Error and std::panic::Location types with QEMU's Error*.

It also has several utility methods, analogous to error_propagate(),
that convert a Result into a return value + Error** pair.  One important
difference is that these propagation methods *panic* if *errp is NULL,
unlike error_propagate() which eats subsequent errors[1].  The reason
for this is that in C you have an error_set*() call at the site where
the error is created, and calls to error_propagate() are relatively rare.

In Rust instead, even though these functions do "propagate" a
qemu_api::Error into a C Error**, there is no error_setg() anywhere that
could check for non-NULL errp and call abort().  error_propagate()'s
behavior of ignoring subsequent errors is generally considered weird,
and there would be a bigger risk of triggering it from Rust code.

[1] This is actually a violation of the preconditions of error_propagate(),
    so it should not happen.  But you never know...

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-05 20:24:51 +02:00
Paolo Bonzini
8714d366e7 util/error: expose Error definition to Rust code
This is used to preserve the file and line in a roundtrip from
C Error to Rust and back to C.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-05 20:24:51 +02:00
Paolo Bonzini
bfe0f6b02a subprojects: add the foreign crate
This is a cleaned up and separated version of the patches at
https://lore.kernel.org/all/20240701145853.1394967-4-pbonzini@redhat.com/
https://lore.kernel.org/all/20240701145853.1394967-5-pbonzini@redhat.com/

Its first user will be the Error bindings; for example a QEMU Error ** can be
converted to a Rust Option using

     unsafe { Option::<Error>::from_foreign(c_error) }

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-05 20:24:51 +02:00
Paolo Bonzini
a95ad49bbf subprojects: add the anyhow crate
This is a standard replacement for Box<dyn Error> which is more efficient (it only
occcupies one word) and provides a backtrace of the error.  This could be plumbed
into &error_abort in the future.

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-05 20:24:51 +02:00
Paolo Bonzini
214518614c rust: qemu-api-macros: add from_bits and into_bits to #[derive(TryInto)]
These const functions make it possible to use enums easily together
with the bitfield-struct crate.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03 22:44:40 +02:00
Paolo Bonzini
9c8ff2a1ed rust: pl011: use the bits macro
This avoids the repeated ".0" when using the Interrupt struct.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03 22:44:40 +02:00
Paolo Bonzini
648fe157d3 rust: add "bits", a custom bitflags implementation
One common thing that device emulation does is manipulate bitmasks, for example
to check whether two bitmaps have common bits.  One example in the pl011 crate
is the checks for pending interrupts, where an interrupt cause corresponds to
at least one interrupt source from a fixed set.

Unfortunately, this is one case where Rust *can* provide some kind of
abstraction but it does so with a rather Perl-ish There Is More Way To
Do It.  It is not something where a crate like "bilge" helps, because
it only covers the packing of bits in a structure; operations like "are
all bits of Y set in X" almost never make sense for bit-packed structs;
you need something else, there are several crates that do it and of course
we're going to roll our own.

In particular I examined three:

- bitmask (https://docs.rs/bitmask/0.5.0/bitmask/) does not support const
  at all.  This is a showstopper because one of the ugly things in the
  current pl011 code is the ugliness of code that defines interrupt masks
  at compile time:

    pub const E: Self = Self(Self::OE.0 | Self::BE.0 | Self::PE.0 | Self::FE.0);

  or even worse:

    const IRQMASK: [u32; 6] = [
      Interrupt::E.0 | Interrupt::MS.0 | Interrupt::RT.0 | Interrupt::TX.0 | Interrupt::RX.0,
      ...
    }

  You would have to use roughly the same code---"bitmask" only helps with
  defining the struct.

- bitmask_enum (https://docs.rs/bitmask-enum/2.2.5/bitmask_enum/) does not
  have a good separation of "valid" and "invalid" bits, so for example "!x"
  will invert all 16 bits if you choose u16 as the representation -- even if
  you only defined 10 bits.  This makes it easier to introduce subtle bugs
  in comparisons.

- bitflags (https://docs.rs/bitflags/2.6.0/bitflags/) is generally the most
  used such crate and is the one that I took most inspiration from with
  respect to the syntax.  It's a pretty sophisticated implementation,
  with a lot of bells and whistles such as an implementation of "Iter"
  that returns the bits one at a time.

The main thing that all of them lack, however, is a way to simplify the
ugly definitions like the above.  "bitflags" includes const methods that
perform AND/OR/XOR of masks (these are necessary because Rust operator
overloading does not support const yet, and therefore overloaded operators
cannot be used in the definition of a "static" variable), but they become
even more verbose and unmanageable, like

  Interrupt::E.union(Interrupt::MS).union(Interrupt::RT).union(Interrupt::TX).union(Interrupt::RX)

This was the main reason to create "bits", which allows something like

  bits!(Interrupt: E | MS | RT | TX | RX)

and expands it 1) add "Interrupt::" in front of all identifiers 2) convert
operators to the wordy const functions like "union".  It supports boolean
operators "&", "|", "^", "!" and parentheses, with a relatively simple
recursive descent parser that's implemented in qemu_api_macros.

Since I don't remember exactly how the macro was developed, I cannot exclude
that it contains code from "bitflags".  Therefore, I am conservatively leaving
in the MIT and Apache 2.0 licenses from bitflags.  In fact, I think there
would be a benefit in being able to push code back to "bitflags" anyway
whenever applicable, so that the two libraries do not diverge too much,
so that's another reason to use this.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03 22:44:40 +02:00
Paolo Bonzini
2409089b87 rust: use native Meson support for clippy and rustdoc
Meson has support for invoking clippy and rustdoc on all crates (1.7.0 for
clippy, 1.8.0 for rustdoc).  Use it instead of the homegrown version; this
requires disabling the multiple_crate_versions lint (the only one that was
enabled from the "cargo" group)---which was not particularly useful anyway
because all dependencies are converted by hand into Meson subprojects.

rustfmt is still not supported.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03 22:42:18 +02:00
Paolo Bonzini
18c9f4a172 rust: cell: remove support for running doctests with "cargo test --doc"
This is not needed anymore now that tests link with libqemuutil.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03 22:42:18 +02:00
Paolo Bonzini
f620cadc0c rust: add qemu-api doctests to "meson test"
Doctests are weird.  They are essentially integration tests, but they're
"ran" by executing rustdoc --test, which takes a compiler-ish
command line.  This is supported by Meson 1.8.0.

Because they run the linker and need all the .o files, run them in the
build jobs rather than the test jobs.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03 22:42:18 +02:00
Paolo Bonzini
4f04a4eaf0 rust: use "objects" for Rust executables as well
libqemuutil is not meant be linked as a whole; if modules are enabled, doing
so results in undefined symbols (corresponding to QMP commands) in
rust/qemu-api/rust-qemu-api-integration.

Support for "objects" in Rust executables is available in Meson 1.8.0; use it
to switching to the same dependencies that C targets use: link_with for
libqemuutil, and objects for everything else.

Reported-by: Bernhard Beschow <shentey@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03 22:42:18 +02:00
Paolo Bonzini
b652d51285 rust: bindings: allow ptr_offset_with_cast
This is produced by recent versions of bindgen:

warning: use of `offset` with a `usize` casted to an `isize`
  --> /builds/bonzini/qemu/rust/target/debug/build/qemu_api-35cb647f4db404b8/out/bindings.inc.rs:39:21
   |
39 |         let byte = *(core::ptr::addr_of!((*this).storage) as *const u8).offset(byte_index as isize);
   |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `(core::ptr::addr_of!((*this).storage) as *const u8).add(byte_index)`
   |
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_offset_with_cast
   = note: `#[warn(clippy::ptr_offset_with_cast)]` on by default
warning: use of `offset` with a `usize` casted to an `isize`
  --> /builds/bonzini/qemu/rust/target/debug/build/qemu_api-35cb647f4db404b8/out/bindings.inc.rs:68:13
   |
68 |             (core::ptr::addr_of_mut!((*this).storage) as *mut u8).offset(byte_index as isize);
   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `(core::ptr::addr_of_mut!((*this).storage) as *mut u8).add(byte_index)`
   |
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_offset_with_cast

This seems to be new in bindgen 0.71.0, possibly related to bindgen
commit 33006185b7878 ("Add raw_ref_macros feature", 2024-11-22).

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-06-03 22:42:18 +02:00
Paolo Bonzini
1297b285cc rust: make declaration of dependent crates more consistent
Crates like "bilge" and "libc" can be shared by more than one directory,
so declare them directly in rust/meson.build.  While at it, make their
variable names end with "_rs" and always add a subproject() statement
(as that pinpoints the error better if the subproject is missing and
cannot be downloaded).

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-05-28 19:35:55 +02:00
Paolo Bonzini
734a1e9eee rust: hpet: rename hpet module to "device"
Follow a similar convention as pl011.

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-05-27 19:21:18 +02:00
Zhao Liu
aef5ac8624 rust: Fix the typos in doc
These typos are found by "cargo spellcheck". Though it outputs a lot of
noise and false positives, there still are some real typos.

Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20250520152750.2542612-6-zhao1.liu@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-05-26 18:04:27 +02:00
Zhao Liu
86c54a3a41 rust: Fix Zhao's email address
No one could find Zhao Liu via zhai1.liu@intel.com.

Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20250520152750.2542612-5-zhao1.liu@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-05-26 18:04:27 +02:00
Peter Maydell
6414b7709d rust: pl011: Cut down amount of text quoted from PL011 TRM
Currently the comments in the Rust pl011 register.rs file include
large amounts of text from the PL011 TRM.  This is much more
commentary than we typically quote from a device reference manual,
and much of it is not relevant to QEMU.  Compress and rephrase the
comments so that we are not quoting such a large volume of TRM text.

We add a URL for the TRM; readers who need more detail on the
function of the register bits can find it there, presented in
context with the overall description of the hardware.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2025-05-14 14:29:47 +01:00
Paolo Bonzini
ac2c4d3aed rust: pl011: Really use RX FIFO depth
While we model a 16-elements RX FIFO since the PL011 model was
introduced in commit cdbdb648b7 ("ARM Versatile Platform Baseboard
emulation"), we only read 1 char at a time!

Have can_receive() return how many elements are available, and use that
in receive().

This is the Rust version of commit 3e0f118f82 ("hw/char/pl011: Really
use RX FIFO depth"); but it also adds back a comment that is present
in commit f576e0733c ("hw/char/pl011: Add support for loopback") and
absent in the Rust code.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-05-12 17:47:39 +02:00
Paolo Bonzini
cc1f4b34d0 rust: pl011: Rename RX FIFO methods
In preparation of having a TX FIFO, rename the RX FIFO methods.
This is the Rust version of commit 40871ca758 ("hw/char/pl011:
Rename RX FIFO methods").

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-05-12 16:08:24 +02:00
Paolo Bonzini
c6b04613bd rust: clippy: enable uninlined_format_args lint
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-05-06 16:02:04 +02:00
Paolo Bonzini
f117857b39 rust: replace c_str! with c"" literals
Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-05-06 16:02:04 +02:00
Paolo Bonzini
b134a09ffa rust: remove offset_of replacement
Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-05-06 16:02:04 +02:00
Paolo Bonzini
5df3fe062f rust: enable clippy::ptr_cast_constness
Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-05-06 16:02:04 +02:00