diff options
| author | Peter Maydell <peter.maydell@linaro.org> | 2024-11-06 21:27:47 +0000 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2024-11-06 21:27:47 +0000 |
| commit | a1dacb66915eb7d08a0596cc97068a37c39930d3 (patch) | |
| tree | daa33d1f6e890c744c85fc08a7b928d1d55b158a /rust/qemu-api/src/zeroable.rs | |
| parent | 63dc36944383f70f1c7a20f6104966d8560300fa (diff) | |
| parent | 951f71ad67bd474aba6925529daf45b747aac86e (diff) | |
| download | focaccia-qemu-a1dacb66915eb7d08a0596cc97068a37c39930d3.tar.gz focaccia-qemu-a1dacb66915eb7d08a0596cc97068a37c39930d3.zip | |
Merge tag 'for-upstream-rust' of https://gitlab.com/bonzini/qemu into staging
* rust: cleanups * rust: integration tests * rust/pl011: add support for migration * rust/pl011: add TYPE_PL011_LUMINARY device * rust: add support for older compilers and bindgen # -----BEGIN PGP SIGNATURE----- # # iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmcrrtIUHHBib256aW5p # QHJlZGhhdC5jb20ACgkQv/vSX3jHroPIBwf/W0Jo87UauGYufhEmoPvWG1EAQEqP # EzNTzem9Iw92VdiSTkAtED0/TSd8RBJOwDfjjusVXZtuMPwpRNgXaFhYTT5gFTMj # Nk3NZGaX/mbNrtdrukdx9mvUWeovytdZDZccTNkpc3oyiqY9NEz06wZ0tCNJEot6 # qO3dEtKXTOQTdx2R3o0oS+2OFDGEEPxZ0PuXN3sClN4iZhGfcIDsjGAWxEh6mCDy # VxqKPdax1Ig1w7M+JMclnpOsVHwcefjHiToNPwhCEGelJ9BZilkViuvBzsVRJJz3 # ptYyywBE0FT8MiKQ/wyf7U64qoizJuIgHoQnUGj98hdgvbUUiW5jcBNY3A== # =s591 # -----END PGP SIGNATURE----- # gpg: Signature made Wed 06 Nov 2024 18:00:50 GMT # gpg: using RSA key F13338574B662389866C7682BFFBD25F78C7AE83 # gpg: issuer "pbonzini@redhat.com" # gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" [full] # gpg: aka "Paolo Bonzini <pbonzini@redhat.com>" [full] # Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4 E2F7 7E15 100C CD36 69B1 # Subkey fingerprint: F133 3857 4B66 2389 866C 7682 BFFB D25F 78C7 AE83 * tag 'for-upstream-rust' of https://gitlab.com/bonzini/qemu: (39 commits) dockerfiles: install bindgen from cargo on Ubuntu 22.04 rust: make rustfmt optional rust: allow older version of bindgen rust: do not use --generate-cstr rust: allow version 1.63.0 of rustc rust: clean up detection of the language rust: do not use MaybeUninit::zeroed() rust: introduce alternative implementation of offset_of! rust: create a cargo workspace rust: synchronize dependencies between subprojects and Cargo.lock rust: silence unknown warnings for the sake of old compilers rust: introduce a c_str macro rust: use std::os::raw instead of core::ffi rust: fix cfgs of proc-macro2 for 1.63.0 rust: patch bilge-impl to allow compilation with 1.63.0 rust/pl011: Use correct masks for IBRD and FBRD rust/pl011: remove commented out C code rust/pl011: add TYPE_PL011_LUMINARY device rust/pl011: move CLK_NAME static to function scope rust/pl011: add support for migration ... Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'rust/qemu-api/src/zeroable.rs')
| -rw-r--r-- | rust/qemu-api/src/zeroable.rs | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/rust/qemu-api/src/zeroable.rs b/rust/qemu-api/src/zeroable.rs new file mode 100644 index 0000000000..13cdb2ccba --- /dev/null +++ b/rust/qemu-api/src/zeroable.rs @@ -0,0 +1,86 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +use std::ptr; + +/// Encapsulates the requirement that +/// `MaybeUninit::<Self>::zeroed().assume_init()` does not cause undefined +/// behavior. This trait in principle could be implemented as just: +/// +/// ``` +/// const ZERO: Self = unsafe { +/// ::core::mem::MaybeUninit::<$crate::bindings::Property>::zeroed().assume_init() +/// }, +/// ``` +/// +/// The need for a manual implementation is only because `zeroed()` cannot +/// be used as a `const fn` prior to Rust 1.75.0. Once we can assume a new +/// enough version of the compiler, we could provide a `#[derive(Zeroable)]` +/// macro to check at compile-time that all struct fields are Zeroable, and +/// use the above blanket implementation of the `ZERO` constant. +/// +/// # Safety +/// +/// Because the implementation of `ZERO` is manual, it does not make +/// any assumption on the safety of `zeroed()`. However, other users of the +/// trait could use it that way. 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 +pub unsafe trait Zeroable: Default { + const ZERO: Self; +} + +unsafe impl Zeroable for crate::bindings::Property__bindgen_ty_1 { + const ZERO: Self = Self { i: 0 }; +} + +unsafe impl Zeroable for crate::bindings::Property { + const ZERO: Self = Self { + name: ptr::null(), + info: ptr::null(), + offset: 0, + bitnr: 0, + bitmask: 0, + set_default: false, + defval: Zeroable::ZERO, + arrayoffset: 0, + arrayinfo: ptr::null(), + arrayfieldsize: 0, + link_type: ptr::null(), + }; +} + +unsafe impl Zeroable for crate::bindings::VMStateDescription { + const ZERO: Self = Self { + name: ptr::null(), + unmigratable: false, + early_setup: false, + version_id: 0, + minimum_version_id: 0, + priority: crate::bindings::MigrationPriority::MIG_PRI_DEFAULT, + pre_load: None, + post_load: None, + pre_save: None, + post_save: None, + needed: None, + dev_unplug_pending: None, + fields: ptr::null(), + subsections: ptr::null(), + }; +} + +unsafe impl Zeroable for crate::bindings::MemoryRegionOps__bindgen_ty_1 { + const ZERO: Self = Self { + min_access_size: 0, + max_access_size: 0, + unaligned: false, + accepts: None, + }; +} + +unsafe impl Zeroable for crate::bindings::MemoryRegionOps__bindgen_ty_2 { + const ZERO: Self = Self { + min_access_size: 0, + max_access_size: 0, + unaligned: false, + }; +} |