Commit graph

24 commits

Author SHA1 Message Date
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
9c00ef6248 docs: update Rust module status
error is new; offset_of is gone.

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
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
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
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
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
1017041ff4 docs: rust: update for newer minimum supported version
Remove leftover notes for Rust changes between 1.63.0 and 1.77.0.

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
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
Paolo Bonzini
0823837224 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>
2025-05-06 16:02:04 +02:00
Paolo Bonzini
51209c2aed rust: let bilge use "let ... else"
"let ... else" was stabilized in 1.65.0; bumping the minimum supported
Rust version means we don't need to patch it out anymore.

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
Paolo Bonzini
e4fb0be1d1 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>
2025-05-06 16:02:04 +02:00
Zhao Liu
db46654af8 rust/hpet: Support migration
Based on commit 1433e38cc8 ("hpet: do not overwrite properties on
post_load"), add the basic migration support to Rust HPET.

The current migration implementation introduces multiple unsafe
callbacks. Before the vmstate builder, one possible cleanup approach is
to wrap callbacks in the vmstate binding using a method similar to the
vmstate_exist_fn macro.

However, this approach would also create a lot of repetitive code (since
vmstate has so many callbacks: pre_load, post_load, pre_save, post_save,
needed and dev_unplug_pending). Although it would be cleaner, it would
somewhat deviate from the path of the vmstate builder.

Therefore, firstly focus on completing the functionality of HPET, and
those current unsafe callbacks can at least clearly indicate the needed
functionality of vmstate. The next step is to consider refactoring
vmstate to move towards the vmstate builder direction.

Additionally, update rust.rst about Rust HPET can support migration.

Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20250414144943.1112885-9-zhao1.liu@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-05-02 17:37:46 +02:00
Paolo Bonzini
f07a5674cf rust: qemu_api_macros: add Wrapper derive macro
Add a derive macro that makes it easy to peel off all the layers of
specialness (UnsafeCell, MaybeUninit, etc.) and just get a pointer
to the wrapped type; and likewise add them back starting from a
*mut.

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-03-06 12:44:46 +01:00
Paolo Bonzini
0b9d05e3c9 rust: cell: add wrapper for FFI types
Inspired by the same-named type in Linux.  This type provides the compiler
with a correct view of what goes on with FFI types.  In addition, it
separates the glue code from the bindgen-generated code, allowing
traits such as Send, Sync or Zeroable to be specified independently
for C and Rust structs.

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-03-06 12:44:46 +01:00
Paolo Bonzini
29b9a66f91 docs: rust: update description of crates
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-02-25 16:18:11 +01:00
Paolo Bonzini
7a2e40866c docs: rust: fix typos
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-02-25 16:18:11 +01:00
Paolo Bonzini
8a420dd109 rust: add module to convert between success/-errno and io::Result
It is a common convention in QEMU to return a positive value in case of
success, and a negated errno value in case of error.  Unfortunately,
using errno portably in Rust is a bit complicated; on Unix the errno
values are supported natively by io::Error, but on Windows they are not;
so, use the libc crate.

This is a set of utility functions that are used by both chardev and
block layer bindings.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-02-25 16:18:08 +01:00
Zhao Liu
eadb83f9a3 rust: add bindings for timer
Add timer bindings to help handle idiomatic Rust callbacks.

Additionally, wrap QEMUClockType in ClockType binding to avoid unsafe
calls in device code.

Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20250210030051.2562726-7-zhao1.liu@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-02-13 12:51:34 +01:00
Paolo Bonzini
590faa03ee rust: bindings for MemoryRegionOps
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-02-13 12:19:34 +01:00
Paolo Bonzini
df45e26a81 rust: docs: document naming convention
As agreed in the "vtables and procedural macros" thread on
the mailing list.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-02-13 12:19:33 +01:00
Paolo Bonzini
2590c02a5f rust: add docs
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-02-07 15:50:59 +01:00