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/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>

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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

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>

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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 M

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>

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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 in

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>

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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
poss

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>

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rust: qdev: support returning errors from realize

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

rust: qemu-api: add tests for Error bindings

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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 utili

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>

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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>

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/

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>

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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@int

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>

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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@i

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>

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rust: replace c_str! with c"" literals

Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

rust: remove offset_of replacement

Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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.co

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>

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rust: qom: fix TODO about zeroability of classes

The proposed suggestion is not correct. First it is not necessary for
*all* classes to be Zeroable, only for Rust-defined ones; classes
defined in C

rust: qom: fix TODO about zeroability of classes

The proposed suggestion is not correct. First it is not necessary for
*all* classes to be Zeroable, only for Rust-defined ones; classes
defined in C never implement ObjectImpl.

Second, the parent class field need not be Zeroable. For example,
ChardevClass's chr_write and chr_be_event fields cannot be NULL,
therefore ChardevClass cannot be Zeroable. However, char_class_init()
initializes them, therefore ChardevClass could be subclassed by Rust code.

Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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rust: use MaybeUninit::zeroed() in const context

Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@

rust: use MaybeUninit::zeroed() in const context

Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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rust: use std::ffi instead of std::os::raw

This is allowed since Rust 1.64.0.

Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-of

rust: use std::ffi instead of std::os::raw

This is allowed since Rust 1.64.0.

Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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rust/timer: Define NANOSECONDS_PER_SECOND binding as u64

NANOSECONDS_PER_SECOND is often used in operations with get_ns(), which
currently returns a u64.

Therefore, define a new NANOSECONDS_PER_SEC

rust/timer: Define NANOSECONDS_PER_SECOND binding as u64

NANOSECONDS_PER_SECOND is often used in operations with get_ns(), which
currently returns a u64.

Therefore, define a new NANOSECONDS_PER_SECOND binding is with u64 type
to eliminate unnecessary type conversions (from u32 to u64).

Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20250414144943.1112885-6-zhao1.liu@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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rust: assertions: Support index field wrapped in BqlCell

Currently, if the `num` field of a varray is not a numeric type, such as
being placed in a wrapper, the array variant of assert_field_type wi

rust: assertions: Support index field wrapped in BqlCell

Currently, if the `num` field of a varray is not a numeric type, such as
being placed in a wrapper, the array variant of assert_field_type will
fail the check.

HPET currently wraps num_timers in BqlCell<>. Although BqlCell<> is not
necessary from strictly speaking, it makes sense for vmstate to respect
BqlCell.

The failure of assert_field_type is because it cannot convert BqlCell<T>
into usize for use as the index. Use a constant 0 instead for the index,
by avoiding $(...)? and extracting the common parts of
assert_field_type! into an internal case.

Commit message based on a patch by Zhao Liu <zhao1.liu@intel.com>.

Link: https://lore.kernel.org/r/20250414144943.1112885-3-zhao1.liu@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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vmstate: support varray for vmstate_clock!

Make vmstate_struct and vmstate_clock more similar; they are basically the
same thing, except for the clock case having a built-in VMStateDescription.

Sig

vmstate: support varray for vmstate_clock!

Make vmstate_struct and vmstate_clock more similar; they are basically the
same thing, except for the clock case having a built-in VMStateDescription.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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rust/vmstate: Add support for field_exists checks

Unfortunately, at present it's not possible to have a const
"with_exist_check" method to append test_fn after vmstate_struct (due
to error on "const

rust/vmstate: Add support for field_exists checks

Unfortunately, at present it's not possible to have a const
"with_exist_check" method to append test_fn after vmstate_struct (due
to error on "constant functions cannot evaluate destructors" for `F`).

Before the vmstate builder, the only way to support "test_fn" is to
extend vmstate_struct macro to add the such new optional member (and
fortunately, Rust can still parse the current expansion!).

Abstract the previous callback implementation of vmstate_validate into
a separate macro, and moves it before vmstate_struct for vmstate_struct
to call.

Note that there's no need to add any extra flag for a new test_fn added
in the VMStateField.

Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20250414144943.1112885-2-zhao1.liu@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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qom: Constify TypeInfo::interfaces

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20250424194905.82506-6-philmd@

qom: Constify TypeInfo::interfaces

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20250424194905.82506-6-philmd@linaro.org>

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qom: Constify TypeInfo::class_data

All callers now correctly expect a const class data.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@l

qom: Constify TypeInfo::class_data

All callers now correctly expect a const class data.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20250424194905.82506-5-philmd@linaro.org>

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qom: Have class_init() take a const data argument

Mechanical change using gsed, then style manually adapted
to pass checkpatch.pl script.

Suggested-by: Richard Henderson <richard.henderson@linaro.o

qom: Have class_init() take a const data argument

Mechanical change using gsed, then style manually adapted
to pass checkpatch.pl script.

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20250424194905.82506-4-philmd@linaro.org>

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