diff options
| -rw-r--r-- | rust/hw/char/pl011/src/device_class.rs | 4 | ||||
| -rw-r--r-- | rust/hw/char/pl011/src/memory_ops.rs | 8 | ||||
| -rw-r--r-- | rust/qemu-api/meson.build | 1 | ||||
| -rw-r--r-- | rust/qemu-api/src/device_class.rs | 8 | ||||
| -rw-r--r-- | rust/qemu-api/src/lib.rs | 1 | ||||
| -rw-r--r-- | rust/qemu-api/src/zeroable.rs | 23 |
6 files changed, 35 insertions, 10 deletions
diff --git a/rust/hw/char/pl011/src/device_class.rs b/rust/hw/char/pl011/src/device_class.rs index 2ad80451e8..08c846aa48 100644 --- a/rust/hw/char/pl011/src/device_class.rs +++ b/rust/hw/char/pl011/src/device_class.rs @@ -4,7 +4,7 @@ use core::ptr::NonNull; -use qemu_api::{bindings::*, definitions::ObjectImpl}; +use qemu_api::{bindings::*, definitions::ObjectImpl, zeroable::Zeroable}; use crate::device::PL011State; @@ -12,7 +12,7 @@ use crate::device::PL011State; pub static VMSTATE_PL011: VMStateDescription = VMStateDescription { name: PL011State::TYPE_INFO.name, unmigratable: true, - ..unsafe { ::core::mem::MaybeUninit::<VMStateDescription>::zeroed().assume_init() } + ..Zeroable::ZERO }; qemu_api::declare_properties! { diff --git a/rust/hw/char/pl011/src/memory_ops.rs b/rust/hw/char/pl011/src/memory_ops.rs index 5a5320e66c..fc69922fbf 100644 --- a/rust/hw/char/pl011/src/memory_ops.rs +++ b/rust/hw/char/pl011/src/memory_ops.rs @@ -2,9 +2,9 @@ // Author(s): Manos Pitsidianakis <manos.pitsidianakis@linaro.org> // SPDX-License-Identifier: GPL-2.0-or-later -use core::{mem::MaybeUninit, ptr::NonNull}; +use core::ptr::NonNull; -use qemu_api::bindings::*; +use qemu_api::{bindings::*, zeroable::Zeroable}; use crate::device::PL011State; @@ -14,11 +14,11 @@ pub static PL011_OPS: MemoryRegionOps = MemoryRegionOps { read_with_attrs: None, write_with_attrs: None, endianness: device_endian::DEVICE_NATIVE_ENDIAN, - valid: unsafe { MaybeUninit::<MemoryRegionOps__bindgen_ty_1>::zeroed().assume_init() }, + valid: Zeroable::ZERO, impl_: MemoryRegionOps__bindgen_ty_2 { min_access_size: 4, max_access_size: 4, - ..unsafe { MaybeUninit::<MemoryRegionOps__bindgen_ty_2>::zeroed().assume_init() } + ..Zeroable::ZERO }, }; diff --git a/rust/qemu-api/meson.build b/rust/qemu-api/meson.build index 1fc3607802..1b0fd40637 100644 --- a/rust/qemu-api/meson.build +++ b/rust/qemu-api/meson.build @@ -5,6 +5,7 @@ _qemu_api_rs = static_library( 'src/lib.rs', 'src/definitions.rs', 'src/device_class.rs', + 'src/zeroable.rs', ], {'.' : bindings_rs}, ), diff --git a/rust/qemu-api/src/device_class.rs b/rust/qemu-api/src/device_class.rs index 4b14cb3ffd..aa6088d9d3 100644 --- a/rust/qemu-api/src/device_class.rs +++ b/rust/qemu-api/src/device_class.rs @@ -31,7 +31,7 @@ macro_rules! define_property { offset: ::core::mem::offset_of!($state, $field) as isize, set_default: true, defval: $crate::bindings::Property__bindgen_ty_1 { u: $defval as u64 }, - ..unsafe { ::core::mem::MaybeUninit::<$crate::bindings::Property>::zeroed().assume_init() } + ..$crate::zeroable::Zeroable::ZERO } }; ($name:expr, $state:ty, $field:expr, $prop:expr, $type:expr$(,)*) => { @@ -41,7 +41,7 @@ macro_rules! define_property { info: $prop, offset: ::core::mem::offset_of!($state, $field) as isize, set_default: false, - ..unsafe { ::core::mem::MaybeUninit::<$crate::bindings::Property>::zeroed().assume_init() } + ..$crate::zeroable::Zeroable::ZERO } }; } @@ -58,7 +58,7 @@ macro_rules! declare_properties { len }] = [ $($prop),*, - unsafe { ::core::mem::MaybeUninit::<$crate::bindings::Property>::zeroed().assume_init() }, + $crate::zeroable::Zeroable::ZERO, ]; }; } @@ -79,7 +79,7 @@ macro_rules! vm_state_description { $vname.as_ptr() },)* unmigratable: true, - ..unsafe { ::core::mem::MaybeUninit::<$crate::bindings::VMStateDescription>::zeroed().assume_init() } + ..$crate::zeroable::Zeroable::ZERO }; } } diff --git a/rust/qemu-api/src/lib.rs b/rust/qemu-api/src/lib.rs index 6bc68076aa..e94a15bb82 100644 --- a/rust/qemu-api/src/lib.rs +++ b/rust/qemu-api/src/lib.rs @@ -29,6 +29,7 @@ unsafe impl Sync for bindings::VMStateDescription {} pub mod definitions; pub mod device_class; +pub mod zeroable; use std::alloc::{GlobalAlloc, Layout}; diff --git a/rust/qemu-api/src/zeroable.rs b/rust/qemu-api/src/zeroable.rs new file mode 100644 index 0000000000..45ec95c9f7 --- /dev/null +++ b/rust/qemu-api/src/zeroable.rs @@ -0,0 +1,23 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +/// Encapsulates the requirement that +/// `MaybeUninit::<Self>::zeroed().assume_init()` does not cause +/// undefined behavior. +/// +/// # Safety +/// +/// Do not add this trait to a type unless all-zeroes is +/// a valid value for the type. In particular, remember that raw +/// pointers can be zero, but references and `NonNull<T>` cannot +/// unless wrapped with `Option<>`. +pub unsafe trait Zeroable: Default { + /// SAFETY: If the trait was added to a type, then by definition + /// this is safe. + const ZERO: Self = unsafe { ::core::mem::MaybeUninit::<Self>::zeroed().assume_init() }; +} + +unsafe impl Zeroable for crate::bindings::Property__bindgen_ty_1 {} +unsafe impl Zeroable for crate::bindings::Property {} +unsafe impl Zeroable for crate::bindings::VMStateDescription {} +unsafe impl Zeroable for crate::bindings::MemoryRegionOps__bindgen_ty_1 {} +unsafe impl Zeroable for crate::bindings::MemoryRegionOps__bindgen_ty_2 {} |