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

core::ffi::c_* types were introduced in Rust 1.64.0.  Use the older types
in std::os::raw, which are now aliases of the types in core::ffi.  There is
no need to compile QEMU as no_std, so this is acceptable as long as we support
a version of Debian with Rust 1.63.0.

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

meson.build

@@ -3953,14 +3953,13 @@ if have_rust and have_system
   bindgen_args = [
     '--disable-header-comment',
     '--raw-line', '// @generated',
-    '--ctypes-prefix', 'core::ffi',
+    '--ctypes-prefix', 'std::os::raw',
     '--formatter', 'rustfmt',
     '--generate-block',
     '--generate-cstr',
     '--impl-debug',
     '--merge-extern-blocks',
     '--no-doc-comments',
-    '--use-core',
     '--with-derive-default',
     '--no-layout-tests',
     '--no-prepend-enum-name',

rust/hw/char/pl011/src/device.rs

@@ -2,9 +2,10 @@
 // Author(s): Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
 // SPDX-License-Identifier: GPL-2.0-or-later
 
-use core::{
-    ffi::{c_int, c_uchar, c_uint, c_void, CStr},
-    ptr::{addr_of, addr_of_mut, NonNull},
+use core::ptr::{addr_of, addr_of_mut, NonNull};
+use std::{
+    ffi::CStr,
+    os::raw::{c_int, c_uchar, c_uint, c_void},
 };
 
 use qemu_api::{
@@ -117,11 +118,10 @@ pub struct PL011Class {
 }
 
 impl qemu_api::definitions::Class for PL011Class {
-    const CLASS_INIT: Option<
-        unsafe extern "C" fn(klass: *mut ObjectClass, data: *mut core::ffi::c_void),
-    > = Some(crate::device_class::pl011_class_init);
+    const CLASS_INIT: Option<unsafe extern "C" fn(klass: *mut ObjectClass, data: *mut c_void)> =
+        Some(crate::device_class::pl011_class_init);
     const CLASS_BASE_INIT: Option<
-        unsafe extern "C" fn(klass: *mut ObjectClass, data: *mut core::ffi::c_void),
+        unsafe extern "C" fn(klass: *mut ObjectClass, data: *mut c_void),
     > = None;
 }
 
@@ -176,11 +176,7 @@ unsafe fn init(&mut self) {
         }
     }
 
-    pub fn read(
-        &mut self,
-        offset: hwaddr,
-        _size: core::ffi::c_uint,
-    ) -> std::ops::ControlFlow<u64, u64> {
+    pub fn read(&mut self, offset: hwaddr, _size: c_uint) -> std::ops::ControlFlow<u64, u64> {
         use RegisterOffset::*;
 
         std::ops::ControlFlow::Break(match RegisterOffset::try_from(offset) {
@@ -562,11 +558,7 @@ pub fn post_load(&mut self, _version_id: u32) -> Result<(), ()> {
 /// readable/writeable from one thread at any time.
 ///
 /// The buffer and size arguments must also be valid.
-pub unsafe extern "C" fn pl011_receive(
-    opaque: *mut core::ffi::c_void,
-    buf: *const u8,
-    size: core::ffi::c_int,
-) {
+pub unsafe extern "C" fn pl011_receive(opaque: *mut c_void, buf: *const u8, size: c_int) {
     unsafe {
         debug_assert!(!opaque.is_null());
         let mut state = NonNull::new_unchecked(opaque.cast::<PL011State>());
@@ -585,7 +577,7 @@ pub fn post_load(&mut self, _version_id: u32) -> Result<(), ()> {
 /// We expect the FFI user of this function to pass a valid pointer, that has
 /// the same size as [`PL011State`]. We also expect the device is
 /// readable/writeable from one thread at any time.
-pub unsafe extern "C" fn pl011_event(opaque: *mut core::ffi::c_void, event: QEMUChrEvent) {
+pub unsafe extern "C" fn pl011_event(opaque: *mut c_void, event: QEMUChrEvent) {
     unsafe {
         debug_assert!(!opaque.is_null());
         let mut state = NonNull::new_unchecked(opaque.cast::<PL011State>());
@@ -656,11 +648,10 @@ pub struct PL011LuminaryClass {
 }
 
 impl qemu_api::definitions::Class for PL011LuminaryClass {
-    const CLASS_INIT: Option<
-        unsafe extern "C" fn(klass: *mut ObjectClass, data: *mut core::ffi::c_void),
-    > = None;
+    const CLASS_INIT: Option<unsafe extern "C" fn(klass: *mut ObjectClass, data: *mut c_void)> =
+        None;
     const CLASS_BASE_INIT: Option<
-        unsafe extern "C" fn(klass: *mut ObjectClass, data: *mut core::ffi::c_void),
+        unsafe extern "C" fn(klass: *mut ObjectClass, data: *mut c_void),
     > = None;
 }
 

rust/hw/char/pl011/src/lib.rs

@@ -46,8 +46,8 @@
 pub mod device_class;
 pub mod memory_ops;
 
-pub const TYPE_PL011: &::core::ffi::CStr = c"pl011";
-pub const TYPE_PL011_LUMINARY: &::core::ffi::CStr = c"pl011_luminary";
+pub const TYPE_PL011: &::std::ffi::CStr = c"pl011";
+pub const TYPE_PL011_LUMINARY: &::std::ffi::CStr = c"pl011_luminary";
 
 /// Offset of each register from the base memory address of the device.
 ///

rust/hw/char/pl011/src/memory_ops.rs

@@ -3,6 +3,7 @@
 // SPDX-License-Identifier: GPL-2.0-or-later
 
 use core::ptr::NonNull;
+use std::os::raw::{c_uint, c_void};
 
 use qemu_api::{bindings::*, zeroable::Zeroable};
 
@@ -22,11 +23,7 @@
     },
 };
 
-unsafe extern "C" fn pl011_read(
-    opaque: *mut core::ffi::c_void,
-    addr: hwaddr,
-    size: core::ffi::c_uint,
-) -> u64 {
+unsafe extern "C" fn pl011_read(opaque: *mut c_void, addr: hwaddr, size: c_uint) -> u64 {
     assert!(!opaque.is_null());
     let mut state = unsafe { NonNull::new_unchecked(opaque.cast::<PL011State>()) };
     let val = unsafe { state.as_mut().read(addr, size) };
@@ -43,12 +40,7 @@
     }
 }
 
-unsafe extern "C" fn pl011_write(
-    opaque: *mut core::ffi::c_void,
-    addr: hwaddr,
-    data: u64,
-    _size: core::ffi::c_uint,
-) {
+unsafe extern "C" fn pl011_write(opaque: *mut c_void, addr: hwaddr, data: u64, _size: c_uint) {
     unsafe {
         assert!(!opaque.is_null());
         let mut state = NonNull::new_unchecked(opaque.cast::<PL011State>());

rust/qemu-api/src/definitions.rs

@@ -4,7 +4,7 @@
 
 //! Definitions required by QEMU when registering a device.
 
-use ::core::ffi::{c_void, CStr};
+use std::{ffi::CStr, os::raw::c_void};
 
 use crate::bindings::{Object, ObjectClass, TypeInfo};
 

rust/qemu-api/src/device_class.rs

@@ -7,7 +7,7 @@ macro_rules! device_class_init {
     ($func:ident, props => $props:ident, realize_fn => $realize_fn:expr, legacy_reset_fn => $legacy_reset_fn:expr, vmsd => $vmsd:ident$(,)*) => {
         pub unsafe extern "C" fn $func(
             klass: *mut $crate::bindings::ObjectClass,
-            _: *mut ::core::ffi::c_void,
+            _: *mut ::std::os::raw::c_void,
         ) {
             let mut dc =
                 ::core::ptr::NonNull::new(klass.cast::<$crate::bindings::DeviceClass>()).unwrap();
@@ -26,7 +26,7 @@ macro_rules! define_property {
     ($name:expr, $state:ty, $field:expr, $prop:expr, $type:expr, default = $defval:expr$(,)*) => {
         $crate::bindings::Property {
             // use associated function syntax for type checking
-            name: ::core::ffi::CStr::as_ptr($name),
+            name: ::std::ffi::CStr::as_ptr($name),
             info: $prop,
             offset: ::core::mem::offset_of!($state, $field) as isize,
             set_default: true,
@@ -37,7 +37,7 @@ macro_rules! define_property {
     ($name:expr, $state:ty, $field:expr, $prop:expr, $type:expr$(,)*) => {
         $crate::bindings::Property {
             // use associated function syntax for type checking
-            name: ::core::ffi::CStr::as_ptr($name),
+            name: ::std::ffi::CStr::as_ptr($name),
             info: $prop,
             offset: ::core::mem::offset_of!($state, $field) as isize,
             set_default: false,

rust/qemu-api/src/lib.rs

@@ -34,7 +34,10 @@ unsafe impl Sync for bindings::VMStateInfo {}
 pub mod vmstate;
 pub mod zeroable;
 
-use std::alloc::{GlobalAlloc, Layout};
+use std::{
+    alloc::{GlobalAlloc, Layout},
+    os::raw::c_void,
+};
 
 #[cfg(HAVE_GLIB_WITH_ALIGNED_ALLOC)]
 extern "C" {
@@ -48,8 +51,8 @@ fn g_aligned_alloc0(
 
 #[cfg(not(HAVE_GLIB_WITH_ALIGNED_ALLOC))]
 extern "C" {
-    fn qemu_memalign(alignment: usize, size: usize) -> *mut ::core::ffi::c_void;
-    fn qemu_vfree(ptr: *mut ::core::ffi::c_void);
+    fn qemu_memalign(alignment: usize, size: usize) -> *mut c_void;
+    fn qemu_vfree(ptr: *mut c_void);
 }
 
 extern "C" {
@@ -114,7 +117,7 @@ fn default() -> Self {
 }
 
 // Sanity check.
-const _: [(); 8] = [(); ::core::mem::size_of::<*mut ::core::ffi::c_void>()];
+const _: [(); 8] = [(); ::core::mem::size_of::<*mut c_void>()];
 
 unsafe impl GlobalAlloc for QemuAllocator {
     unsafe fn alloc(&self, layout: Layout) -> *mut u8 {

rust/qemu-api/src/vmstate.rs

@@ -56,7 +56,7 @@ macro_rules! vmstate_single_test {
         $crate::bindings::VMStateField {
             name: ::core::concat!(::core::stringify!($field_name), 0)
                 .as_bytes()
-                .as_ptr() as *const ::core::ffi::c_char,
+                .as_ptr() as *const ::std::os::raw::c_char,
             err_hint: ::core::ptr::null(),
             offset: ::core::mem::offset_of!($struct_name, $field_name),
             size: $size,
@@ -133,7 +133,7 @@ macro_rules! vmstate_array {
         $crate::bindings::VMStateField {
             name: ::core::concat!(::core::stringify!($field_name), 0)
                 .as_bytes()
-                .as_ptr() as *const ::core::ffi::c_char,
+                .as_ptr() as *const ::std::os::raw::c_char,
             err_hint: ::core::ptr::null(),
             offset: ::core::mem::offset_of!($struct_name, $field_name),
             size: $size,
@@ -181,7 +181,7 @@ macro_rules! vmstate_struct_pointer_v {
         $crate::bindings::VMStateField {
             name: ::core::concat!(::core::stringify!($field_name), 0)
                 .as_bytes()
-                .as_ptr() as *const ::core::ffi::c_char,
+                .as_ptr() as *const ::std::os::raw::c_char,
             err_hint: ::core::ptr::null(),
             offset: ::core::mem::offset_of!($struct_name, $field_name),
             size: ::core::mem::size_of::<*const $type>(),
@@ -206,7 +206,7 @@ macro_rules! vmstate_array_of_pointer {
         $crate::bindings::VMStateField {
             name: ::core::concat!(::core::stringify!($field_name), 0)
                 .as_bytes()
-                .as_ptr() as *const ::core::ffi::c_char,
+                .as_ptr() as *const ::std::os::raw::c_char,
             version_id: $version_id,
             num: $num as _,
             info: unsafe { $info },
@@ -231,7 +231,7 @@ macro_rules! vmstate_array_of_pointer_to_struct {
         $crate::bindings::VMStateField {
             name: ::core::concat!(::core::stringify!($field_name), 0)
                 .as_bytes()
-                .as_ptr() as *const ::core::ffi::c_char,
+                .as_ptr() as *const ::std::os::raw::c_char,
             version_id: $version_id,
             num: $num as _,
             vmsd: unsafe { $vmsd },

rust/qemu-api/tests/tests.rs

@@ -2,7 +2,7 @@
 // Author(s): Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
 // SPDX-License-Identifier: GPL-2.0-or-later
 
-use core::ffi::CStr;
+use std::{ffi::CStr, os::raw::c_void};
 
 use qemu_api::{
     bindings::*,
@@ -64,11 +64,10 @@ impl ObjectImpl for DummyState {
     }
 
     impl Class for DummyClass {
-        const CLASS_INIT: Option<
-            unsafe extern "C" fn(klass: *mut ObjectClass, data: *mut core::ffi::c_void),
-        > = Some(dummy_class_init);
+        const CLASS_INIT: Option<unsafe extern "C" fn(klass: *mut ObjectClass, data: *mut c_void)> =
+            Some(dummy_class_init);
         const CLASS_BASE_INIT: Option<
-            unsafe extern "C" fn(klass: *mut ObjectClass, data: *mut core::ffi::c_void),
+            unsafe extern "C" fn(klass: *mut ObjectClass, data: *mut c_void),
         > = None;
     }