> > > + # > WARNING: Project specifies a minimum meson_version '>=0.63.0'
> > > but
> > > + # > uses features which were added in newer versions:
> > > + # > * 0.64.0: {'fs.copyfile'}
> > > + # > * 1.0.0: {'dependencies arg in rust.bindgen', 'module rust as
> > > stable module'}
> > > + rust_bindgen = import('rust')
> > > +
> > > + # We need one generated_rs target per target, so give them
> > > + # target-specific names.
> > > + copy = fs.copyfile('rust/wrapper.h',
> > > + target + '_wrapper.h')
> > > + generated_rs = rust_bindgen.bindgen(
> > > + input: copy,
> > > + dependencies: arch_deps + lib_deps,
> > > + output: target + '-generated.rs',
> > > + include_directories: include_directories('.', 'include'),
> > > + args: [
> > > + '--ctypes-prefix', 'core::ffi',
> > > + '--formatter', 'rustfmt',
> > > + '--generate-block',
> > > + '--generate-cstr',
> > > + '--impl-debug',
> > > + '--merge-extern-blocks',
> > > + '--no-doc-comments',
> > > + '--no-include-path-detection',
> > > + '--use-core',
> > > + '--with-derive-default',
> > > + '--allowlist-file', meson.project_source_root() +
> > > '/include/.*',
> > > + '--allowlist-file', meson.project_source_root() + '/.*',
> > > + '--allowlist-file', meson.project_build_root() + '/.*'
> > > + ],
> > > + )
> > > +
> > > + if target in rust_targets
> > > + rust_hw = ss.source_set()
> > > + foreach t: rust_targets[target]
> > > + rust_device_cargo = custom_target(t['name'],
> > > + output: t['output'],
> > > + depends: [generated_rs],
> > > + build_always_stale: true,
> > > + command: t['command'])
> > > + rust_dep = declare_dependency(link_args: [
> > > + '-Wl,--whole-archive',
> > > + t['output-path'],
> > > + '-Wl,--no-whole-archive'
> > > + ],
> > > + sources: [rust_device_cargo])
> > > + rust_hw.add(rust_dep)
> > > + endforeach
> > > + rust_hw_config = rust_hw.apply(config_target, strict: false)
> > > + arch_srcs += rust_hw_config.sources()
> > > + arch_deps += rust_hw_config.dependencies()
> > > + endif
> > > + endif
> > > +
> > > lib = static_library('qemu-' + target,
> > > sources: arch_srcs + genh,
> > > dependencies: lib_deps,
> > > diff --git a/rust/.gitignore b/rust/.gitignore
> > > new file mode 100644
> > > index 0000000000..1bf71b1f68
> > > --- /dev/null
> > > +++ b/rust/.gitignore
> > > @@ -0,0 +1,3 @@
> > > +# Ignore any cargo development build artifacts; for qemu-wide builds,
> > > all build
> > > +# artifacts will go to the meson build directory.
> > > +target
> > > diff --git a/rust/meson.build b/rust/meson.build
> > > new file mode 100644
> > > index 0000000000..435abd3e1c
> > > --- /dev/null
> > > +++ b/rust/meson.build
> > > @@ -0,0 +1,129 @@
> > > +# Supported hosts
> > > +rust_supported_oses = {
> > > + 'linux': '-unknown-linux-gnu',
> > > + 'darwin': '-apple-darwin',
> > > + 'windows': '-pc-windows-gnu'
> > > +}
> >
> > Does the current test cover windows and apple? If not, I think we can
> > add these two platforms later on.
>
> Do you mean the test for supported OSes?
Yes.
> This is for future-proofing the Rust integration in general. I haven't been
> able to compile under macos yet because bindgen cannot find the system clang
> header. I also don't have a windows pc to test it on. But it should work
> theoretically under all three.
Yes, they should work. EMM, but there is no particular need for them at
the moment, so just to be safe, we can put these two platforms on hold
for now, and they can be easily added when the tests are covered.
A TODO can remind support for them.
> >
> > > +rust_supported_cpus = ['x86_64', 'aarch64']
> >
> > Similarly, here I have another question, x-pl011-rust in arm virt machine
> > I understand should only run on ARM platform, right? So compiling to
> > x86_64 doesn't seem necessary at the moment?
>
> This refers to the host cpu not the virtualized ones, you can run
> qemu-system-aarch64 under x86_64
Thanks, I see.
> > > +# Future-proof the above definitions against any change in the root
> > > meson.build file:
> > > +foreach rust_os: rust_supported_oses.keys()
> > > + if not supported_oses.contains(rust_os)
> > > + message()
> > > + warning('UNSUPPORTED OS VALUES IN ' + meson.current_source_dir() +
> > > '/meson.build')
> > > + message()
> > > + message('This meson.build file claims OS `+' + rust_os + '` is
> > > supported but')
> > > + message('it is not included in the global supported OSes list in')
> > > + message(meson.global_source_root() + '/meson.build.')
> > > + endif
> > > +endforeach
> > > +foreach rust_cpu: rust_supported_cpus
> > > + if not supported_cpus.contains(rust_cpu)
> > > + message()
> > > + warning('UNSUPPORTED CPU VALUES IN ' + meson.current_source_dir() +
> > > '/meson.build')
> > > + message()
> > > + message('This meson.build file claims CPU `+' + rust_cpu + '` is
> > > supported but')
> > > + message('it is not included in the global supported CPUs list in')
> > > + message(meson.global_source_root() + '/meson.build.')
> > > + endif
> > > +endforeach
> > > +
> > > +# FIXME: retrieve target triple from meson and construct
> > > rust_target_triple
> > > +if meson.is_cross_build()
> > > + message()
> > > + error('QEMU does not support cross compiling with Rust enabled.')
> > > +endif
> >
> > Is the check here to avoid inconsistencies between cross-build's target
> > and rust_target_triple?
> >
> > If target consistency is not guaranteed, then it seems custom
> > rust_target_triple
> > is useless, right? please educate me if I am wrong ;-)
>
> It is, correct. I was hoping someone on the list would have advice on how to
> best do this (see the FIXME comment right above)
Yes, Daniel has said what I would say in his reply.
> >
> > > +# FIXME: These are the latest stable versions, refine to actual minimum
> > > ones.
> > > +msrv = {
> > > + 'rustc': '1.79.0',
> > > + 'cargo': '1.79.0',
> > > + 'bindgen': '0.69.4',
> > > +}
> > > +
> > > +# rustup = find_program('rustup', required: false)
> > > +foreach bin_dep: msrv.keys()
> > > + bin = find_program(bin_dep, required: true)
> > > + if bin.version() < msrv[bin_dep]
> > > + if bin_dep == 'bindgen' and get_option('wrap_mode') != 'nodownload'
> >
> > What about adding a download info here?
> >
> > It took a long time for my bindgen-cli to update quietly, and for a
> > moment I thought it was stuck here...
> >
> > e.g., message('Installing bindgen-cli...')
> >
> > Or can we just report the error and let users install bindgen-cli
> > themselves?
>
> Now that I think about it again I agree it's better to not mess with
> user/system installations without asking.
I agree. Thanks!
> > > + run_command(cargo, 'install', 'bindgen-cli', capture: true, check:
> > > true)
> > > + bin = find_program(bin_dep, required: true)
> > > + if bin.version() >= msrv[bin_dep]
> > > + continue
> > > + endif
> > > + endif
> > > + message()
> > > + error(bin_dep + ' version ' + bin.version() + ' is unsupported:
> > > Please upgrade to at least ' + msrv[bin_dep])
> > > + endif
> > > +endforeach
> > > +
> > > +rust_target_triple = get_option('with_rust_target_triple')
> > > +
> > > +if rust_target_triple == ''
> > > + if not supported_oses.contains(host_os)
> > > + message()
> > > + error('QEMU does not support `' + host_os +'` as a Rust platform.')
> > > + elif not supported_cpus.contains(host_arch)
> > > + message()
> > > + error('QEMU does not support `' + host_arch +'` as a Rust
> > > architecture.')
> > > + endif
> > > + rust_target_triple = host_arch + rust_supported_oses[host_os]
> > > + if host_os == 'windows' and host_arch == 'aarch64'
> > > + rust_target_triple += 'llvm'
> > > + endif
> > > +else
> > > + # verify rust_target_triple if given as an option
> > > + rustc = find_program('rustc', required: true)
> > > + rustc_targets = run_command(rustc, '--print', 'target-list', capture:
> > > true, check: true).stdout().strip().split()
> > > + if not rustc_targets.contains(rust_target_triple)
> > > + message()
> > > + error('Given rust_target_triple ' + rust_target_triple + ' is not
> > > listed in rustc --print target-list output')
> > > + endif
> >
> > It seems rust_target_triple missed support check, we should use
> > rust_supported_cpus
> > + rust_supported_oses to check rust_target_triple, right? ;-)
> >
> > > +endif
> > > +
> > > +
> >
> > An extra blank line :-)
> >
> > > +rust_targets = {}
> > > +
> > > +cargo_wrapper = [
> > > + find_program(meson.global_source_root() / 'scripts/cargo_wrapper.py'),
> > > + '--config-headers', meson.project_build_root() / 'config-host.h',
> > > + '--meson-build-root', meson.project_build_root(),
> > > + '--meson-build-dir', meson.current_build_dir(),
> > > + '--meson-source-dir', meson.current_source_dir(),
> > > +]
> > > +
> > > +if get_option('b_colorout') != 'never'
> > > + cargo_wrapper += ['--color', 'always']
> > > +endif
> > > +
> > > +if get_option('optimization') in ['0', '1', 'g']
> > > + rs_build_type = 'debug'
> > > +else
> > > + rs_build_type = 'release'
> > > +endif
> >
> > Could we decouple 'optimization' with cargo's opt-level (maybe in the
> > future)?
> >
> > Or we could add new option to specify custom rust opt-level, which will
> > set the environment varialbe CARGO_PROFILE_<profile_name>_OPT_LEVEL and
> > override the default opt-level in Cargo.toml.
>
> optimization here refers to LLVM's opt flags directly, so I think it makes
> sense to follow the project-wide compiler settings?
Oh, yes. But I think the choice of debug or release is best based on the
debug info. What about this?
if get_option('debug')
rs_build_type = 'debug'
else
rs_build_type = 'release'
endif
get_option('debug') would apply -g flag, and that flag is mapped to debuginfo=2,
which is the default debuginfo level for debug version.
> > > +# Collect metadata for each (crate,qemu-target,compiler-target)
> > > combination.
> > > +# Rust meson targets cannot be defined a priori because they depend on
> > > bindgen
> > > +# generation that is created for each emulation target separately. Thus
> > > Rust
> > > +# meson targets will be defined for each target after the target-specific
> > > +# bindgen dependency is declared.
> > > +rust_hw_target_list = {}
> > > +
> > > +foreach rust_hw_target, rust_hws: rust_hw_target_list
> > > + foreach rust_hw_dev: rust_hws
> > > + output = meson.current_build_dir() / rust_target_triple /
> > > rs_build_type / rust_hw_dev['output']
> > > + crate_metadata = {
> > > + 'name': rust_hw_dev['name'],
> > > + 'output': [rust_hw_dev['output']],
> > > + 'output-path': output,
> > > + 'command': [cargo_wrapper,
> > > + '--crate-dir', meson.current_source_dir() /
> > > rust_hw_dev['dirname'],
> > > + '--profile', rs_build_type,
> > > + '--target-triple', rust_target_triple,
> > > + '--outdir', '@OUTDIR@',
> > > + 'build-lib'
> > > + ]
> > > + }
> > > + rust_targets += { rust_hw_target: [crate_metadata] }
> > > + endforeach
> > > +endforeach
> > > diff --git a/rust/wrapper.h b/rust/wrapper.h
> > > new file mode 100644
> > > index 0000000000..bcf808c8d7
> > > --- /dev/null
> > > +++ b/rust/wrapper.h
> > > @@ -0,0 +1,39 @@
> > > +/*
> > > + * QEMU System Emulator
> > > + *
> > > + * Copyright (c) 2003-2020 Fabrice Bellard
> >
> > Here should the author be yourself?
>
> Technically I copy pasted this file from the main.c executable so it's a
> derived work :D
>
It's a totally new file, and it is used to derive other files. These are
all significant changes. At least for 2024, I think you can declare
copyright here. :-)
Thanks,
Zhao
