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helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.421, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-1.699, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Now that device_class_set_props() takes a const pointer, the only part of "define_property!" that needs to be non-const is the call to try_into(). This in turn will only break if offset_of returns a value with the most significant bit set (i.e. a struct size that is >=2^31 or >= 2^63, respectively on 32- and 64-bit system), which is impossible. Just use a cast and clean everything up to remove the run-time initialization. This also removes a use of OnceLock, which was only stabilized in 1.70.0. Signed-off-by: Paolo Bonzini Reviewed-by: Zhao Liu --- rust/qemu-api/src/device_class.rs | 42 ++++++------------------------- 1 file changed, 8 insertions(+), 34 deletions(-) diff --git a/rust/qemu-api/src/device_class.rs b/rust/qemu-api/src/device_class.rs index 5aba426d243..d885f2fcf19 100644 --- a/rust/qemu-api/src/device_class.rs +++ b/rust/qemu-api/src/device_class.rs @@ -2,10 +2,6 @@ // Author(s): Manos Pitsidianakis // SPDX-License-Identifier: GPL-2.0-or-later -use std::sync::OnceLock; - -use crate::bindings::Property; - #[macro_export] macro_rules! device_class_init { ($func:ident, props => $props:ident, realize_fn => $realize_fn:expr, legacy_reset_fn => $legacy_reset_fn:expr, vmsd => $vmsd:ident$(,)*) => { @@ -19,7 +15,7 @@ macro_rules! device_class_init { dc.as_mut().realize = $realize_fn; dc.as_mut().vmsd = &$vmsd; $crate::bindings::device_class_set_legacy_reset(dc.as_mut(), $legacy_reset_fn); - $crate::bindings::device_class_set_props(dc.as_mut(), $props.as_mut_ptr()); + $crate::bindings::device_class_set_props(dc.as_mut(), $props.as_ptr()); } } }; @@ -32,9 +28,7 @@ macro_rules! define_property { // use associated function syntax for type checking name: ::core::ffi::CStr::as_ptr($name), info: $prop, - offset: ::core::mem::offset_of!($state, $field) - .try_into() - .expect("Could not fit offset value to type"), + offset: ::core::mem::offset_of!($state, $field) as isize, set_default: true, defval: $crate::bindings::Property__bindgen_ty_1 { u: $defval.into() }, ..unsafe { ::core::mem::MaybeUninit::<$crate::bindings::Property>::zeroed().assume_init() } @@ -45,47 +39,27 @@ macro_rules! define_property { // use associated function syntax for type checking name: ::core::ffi::CStr::as_ptr($name), info: $prop, - offset: ::core::mem::offset_of!($state, $field) - .try_into() - .expect("Could not fit offset value to type"), + offset: ::core::mem::offset_of!($state, $field) as isize, set_default: false, ..unsafe { ::core::mem::MaybeUninit::<$crate::bindings::Property>::zeroed().assume_init() } } }; } -#[repr(C)] -pub struct Properties(pub OnceLock<[Property; N]>, pub fn() -> [Property; N]); - -impl Properties { - pub fn as_mut_ptr(&mut self) -> *mut Property { - _ = self.0.get_or_init(self.1); - self.0.get_mut().unwrap().as_mut_ptr() - } -} - #[macro_export] macro_rules! declare_properties { ($ident:ident, $($prop:expr),*$(,)*) => { - - const fn _calc_prop_len() -> usize { + pub static $ident: [$crate::bindings::Property; { let mut len = 1; $({ _ = stringify!($prop); len += 1; })* len - } - const PROP_LEN: usize = _calc_prop_len(); - - fn _make_properties() -> [$crate::bindings::Property; PROP_LEN] { - [ - $($prop),*, - unsafe { ::core::mem::MaybeUninit::<$crate::bindings::Property>::zeroed().assume_init() }, - ] - } - - pub static mut $ident: $crate::device_class::Properties = $crate::device_class::Properties(::std::sync::OnceLock::new(), _make_properties); + }] = [ + $($prop),*, + unsafe { ::core::mem::MaybeUninit::<$crate::bindings::Property>::zeroed().assume_init() }, + ]; }; }