The VMStateDescriptionBuilder already needs const_refs_to_static, so
use it to remove the need for vmstate_clock! and vmstate_struct!,
as well as to simplify the implementation for scalars.
If the consts in the VMState trait can reference to static
VMStateDescription, scalars do not need the info_enum_to_ref!
indirection and structs can implement the VMState trait themselves.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
docs/devel/rust.rst | 5 -
rust/hw/char/pl011/src/device_class.rs | 14 +-
rust/hw/timer/hpet/src/hpet.rs | 8 +-
rust/qemu-api/src/assertions.rs | 4 -
rust/qemu-api/src/vmstate.rs | 232 +++++++------------------
rust/qemu-api/tests/vmstate_tests.rs | 65 ++++---
6 files changed, 116 insertions(+), 212 deletions(-)
diff --git a/docs/devel/rust.rst b/docs/devel/rust.rst
index ed1c765e722..12c9bde4f5c 100644
--- a/docs/devel/rust.rst
+++ b/docs/devel/rust.rst
@@ -80,11 +80,6 @@ patches are welcome:
* ``&raw`` (stable in 1.82.0).
-* referencing statics in constants (stable in 1.83.0). For now use a const
- function; this is an important limitation for QEMU's migration stream
- architecture (VMState). Right now, VMState lacks type safety because
- it is hard to place the ``VMStateField`` definitions in traits.
-
Associated const equality would be nice to have for some users of
``callbacks::FnCall``, but is still experimental. Const assertions
are used instead.
diff --git a/rust/hw/char/pl011/src/device_class.rs b/rust/hw/char/pl011/src/device_class.rs
index ed72bfad25f..e4a9499bda7 100644
--- a/rust/hw/char/pl011/src/device_class.rs
+++ b/rust/hw/char/pl011/src/device_class.rs
@@ -4,9 +4,9 @@
use qemu_api::{
bindings::{qdev_prop_bool, qdev_prop_chr},
- prelude::*,
+ impl_vmstate_struct,
vmstate::{VMStateDescription, VMStateDescriptionBuilder},
- vmstate_clock, vmstate_fields, vmstate_of, vmstate_struct, vmstate_subsections, vmstate_unused,
+ vmstate_fields, vmstate_of, vmstate_subsections, vmstate_unused,
};
use crate::device::{PL011Registers, PL011State};
@@ -19,11 +19,12 @@
.minimum_version_id(1)
.needed(&PL011State::clock_needed)
.fields(vmstate_fields! {
- vmstate_clock!(PL011State, clock),
+ vmstate_of!(PL011State, clock),
})
.build();
-static VMSTATE_PL011_REGS: VMStateDescription<PL011Registers> =
+impl_vmstate_struct!(
+ PL011Registers,
VMStateDescriptionBuilder::<PL011Registers>::new()
.name(c"pl011/regs")
.version_id(2)
@@ -45,7 +46,8 @@
vmstate_of!(PL011Registers, read_count),
vmstate_of!(PL011Registers, read_trigger),
})
- .build();
+ .build()
+);
pub const VMSTATE_PL011: VMStateDescription<PL011State> =
VMStateDescriptionBuilder::<PL011State>::new()
@@ -55,7 +57,7 @@
.post_load(&PL011State::post_load)
.fields(vmstate_fields! {
vmstate_unused!(core::mem::size_of::<u32>()),
- vmstate_struct!(PL011State, regs, &VMSTATE_PL011_REGS, BqlRefCell<PL011Registers>),
+ vmstate_of!(PL011State, regs),
})
.subsections(vmstate_subsections! {
VMSTATE_PL011_CLOCK
diff --git a/rust/hw/timer/hpet/src/hpet.rs b/rust/hw/timer/hpet/src/hpet.rs
index 1ed1cb7dcaf..be3b9afa316 100644
--- a/rust/hw/timer/hpet/src/hpet.rs
+++ b/rust/hw/timer/hpet/src/hpet.rs
@@ -16,6 +16,7 @@
qdev_prop_uint32, qdev_prop_uint8,
},
cell::{BqlCell, BqlRefCell},
+ impl_vmstate_struct,
irq::InterruptSource,
memory::{
hwaddr, MemoryRegion, MemoryRegionOps, MemoryRegionOpsBuilder, MEMTXATTRS_UNSPECIFIED,
@@ -27,7 +28,7 @@
sysbus::{SysBusDevice, SysBusDeviceImpl},
timer::{Timer, CLOCK_VIRTUAL, NANOSECONDS_PER_SECOND},
vmstate::{VMStateDescription, VMStateDescriptionBuilder},
- vmstate_fields, vmstate_of, vmstate_struct, vmstate_subsections, vmstate_validate,
+ vmstate_fields, vmstate_of, vmstate_subsections, vmstate_validate,
};
use crate::fw_cfg::HPETFwConfig;
@@ -967,7 +968,7 @@ impl ObjectImpl for HPETState {
})
.build();
-static VMSTATE_HPET_TIMER: VMStateDescription<HPETTimer> =
+const VMSTATE_HPET_TIMER: VMStateDescription<HPETTimer> =
VMStateDescriptionBuilder::<HPETTimer>::new()
.name(c"hpet_timer")
.version_id(1)
@@ -982,6 +983,7 @@ impl ObjectImpl for HPETState {
vmstate_of!(HPETTimer, qemu_timer),
})
.build();
+impl_vmstate_struct!(HPETTimer, VMSTATE_HPET_TIMER);
const VALIDATE_TIMERS_NAME: &CStr = c"num_timers must match";
@@ -998,7 +1000,7 @@ impl ObjectImpl for HPETState {
vmstate_of!(HPETState, counter),
vmstate_of!(HPETState, num_timers_save).with_version_id(2),
vmstate_validate!(HPETState, VALIDATE_TIMERS_NAME, HPETState::validate_num_timers),
- vmstate_struct!(HPETState, timers[0 .. num_timers], &VMSTATE_HPET_TIMER, BqlRefCell<HPETTimer>, HPETState::validate_num_timers).with_version_id(0),
+ vmstate_of!(HPETState, timers[0 .. num_timers], HPETState::validate_num_timers).with_version_id(0),
})
.subsections(vmstate_subsections!(
VMSTATE_HPET_RTC_IRQ_LEVEL,
diff --git a/rust/qemu-api/src/assertions.rs b/rust/qemu-api/src/assertions.rs
index a2d38c877df..80db0de099f 100644
--- a/rust/qemu-api/src/assertions.rs
+++ b/rust/qemu-api/src/assertions.rs
@@ -95,10 +95,6 @@ fn types_must_be_equal<T, U>(_: &T)
($t:ty, $i:tt, $ti:ty) => {
$crate::assert_field_type!(@internal v, $ti, $t, v.$i);
};
-
- ($t:ty, $i:tt, $ti:ty, num = $num:ident) => {
- $crate::assert_field_type!(@internal v, $ti, $t, v.$i[0]);
- };
}
/// Assert that an expression matches a pattern. This can also be
diff --git a/rust/qemu-api/src/vmstate.rs b/rust/qemu-api/src/vmstate.rs
index 228d748b6b7..959d0a01fe3 100644
--- a/rust/qemu-api/src/vmstate.rs
+++ b/rust/qemu-api/src/vmstate.rs
@@ -11,10 +11,11 @@
//! migration format for a struct. This is based on the [`VMState`] trait,
//! which is defined by all migrateable types.
//!
-//! * [`impl_vmstate_forward`](crate::impl_vmstate_forward) and
+//! * [`impl_vmstate_forward`](crate::impl_vmstate_forward),
+//! * [`impl_vmstate_struct`](crate::impl_vmstate_struct),
//! [`impl_vmstate_bitsized`](crate::impl_vmstate_bitsized), which help with
-//! the definition of the [`VMState`] trait (respectively for transparent
-//! structs and for `bilge`-defined types)
+//! the definition of the [`VMState`] trait; they are respectively for
+//! transparent structs, nested structs and `bilge`-defined types)
//!
//! * helper macros to declare a device model state struct, in particular
//! [`vmstate_subsections`](crate::vmstate_subsections) and
@@ -24,7 +25,11 @@
//! `include/migration/vmstate.h`. These are not type-safe and only provide
//! functionality that is missing from `vmstate_of!`.
-use core::{marker::PhantomData, mem, ptr::NonNull};
+use core::{
+ marker::PhantomData,
+ mem,
+ ptr::{addr_of, NonNull},
+};
use std::ffi::{c_int, c_void, CStr};
pub use crate::bindings::{MigrationPriority, VMStateField};
@@ -33,6 +38,7 @@
callbacks::FnCall,
errno::{into_neg_errno, Errno},
prelude::*,
+ qdev,
qom::Owned,
zeroable::Zeroable,
};
@@ -74,70 +80,6 @@ const fn phantom__<T>(_: &T) -> ::core::marker::PhantomData<T> { ::core::marker:
};
}
-/// Workaround for lack of `const_refs_static`: references to global variables
-/// can be included in a `static`, but not in a `const`; unfortunately, this
-/// is exactly what would go in the `VMStateField`'s `info` member.
-///
-/// This enum contains the contents of the `VMStateField`'s `info` member,
-/// but as an `enum` instead of a pointer.
-#[allow(non_camel_case_types)]
-pub enum VMStateFieldType {
- null,
- vmstate_info_bool,
- vmstate_info_int8,
- vmstate_info_int16,
- vmstate_info_int32,
- vmstate_info_int64,
- vmstate_info_uint8,
- vmstate_info_uint16,
- vmstate_info_uint32,
- vmstate_info_uint64,
- vmstate_info_timer,
-}
-
-/// Workaround for lack of `const_refs_static`. Converts a `VMStateFieldType`
-/// to a `*const VMStateInfo`, for inclusion in a `VMStateField`.
-#[macro_export]
-macro_rules! info_enum_to_ref {
- ($e:expr) => {
- unsafe {
- match $e {
- $crate::vmstate::VMStateFieldType::null => ::core::ptr::null(),
- $crate::vmstate::VMStateFieldType::vmstate_info_bool => {
- ::core::ptr::addr_of!($crate::bindings::vmstate_info_bool)
- }
- $crate::vmstate::VMStateFieldType::vmstate_info_int8 => {
- ::core::ptr::addr_of!($crate::bindings::vmstate_info_int8)
- }
- $crate::vmstate::VMStateFieldType::vmstate_info_int16 => {
- ::core::ptr::addr_of!($crate::bindings::vmstate_info_int16)
- }
- $crate::vmstate::VMStateFieldType::vmstate_info_int32 => {
- ::core::ptr::addr_of!($crate::bindings::vmstate_info_int32)
- }
- $crate::vmstate::VMStateFieldType::vmstate_info_int64 => {
- ::core::ptr::addr_of!($crate::bindings::vmstate_info_int64)
- }
- $crate::vmstate::VMStateFieldType::vmstate_info_uint8 => {
- ::core::ptr::addr_of!($crate::bindings::vmstate_info_uint8)
- }
- $crate::vmstate::VMStateFieldType::vmstate_info_uint16 => {
- ::core::ptr::addr_of!($crate::bindings::vmstate_info_uint16)
- }
- $crate::vmstate::VMStateFieldType::vmstate_info_uint32 => {
- ::core::ptr::addr_of!($crate::bindings::vmstate_info_uint32)
- }
- $crate::vmstate::VMStateFieldType::vmstate_info_uint64 => {
- ::core::ptr::addr_of!($crate::bindings::vmstate_info_uint64)
- }
- $crate::vmstate::VMStateFieldType::vmstate_info_timer => {
- ::core::ptr::addr_of!($crate::bindings::vmstate_info_timer)
- }
- }
- }
- };
-}
-
/// A trait for types that can be included in a device's migration stream. It
/// provides the base contents of a `VMStateField` (minus the name and offset).
///
@@ -148,12 +90,6 @@ macro_rules! info_enum_to_ref {
/// to implement it except via macros that do it for you, such as
/// `impl_vmstate_bitsized!`.
pub unsafe trait VMState {
- /// The `info` member of a `VMStateField` is a pointer and as such cannot
- /// yet be included in the [`BASE`](VMState::BASE) associated constant;
- /// this is only allowed by Rust 1.83.0 and newer. For now, include the
- /// member as an enum which is stored in a separate constant.
- const SCALAR_TYPE: VMStateFieldType = VMStateFieldType::null;
-
/// The base contents of a `VMStateField` (minus the name and offset) for
/// the type that is implementing the trait.
const BASE: VMStateField;
@@ -168,12 +104,6 @@ pub unsafe trait VMState {
};
}
-/// Internal utility function to retrieve a type's `VMStateFieldType`;
-/// used by [`vmstate_of!`](crate::vmstate_of).
-pub const fn vmstate_scalar_type<T: VMState>(_: PhantomData<T>) -> VMStateFieldType {
- T::SCALAR_TYPE
-}
-
/// Internal utility function to retrieve a type's `VMStateField`;
/// used by [`vmstate_of!`](crate::vmstate_of).
pub const fn vmstate_base<T: VMState>(_: PhantomData<T>) -> VMStateField {
@@ -201,7 +131,8 @@ pub const fn vmstate_varray_flag<T: VMState>(_: PhantomData<T>) -> VMStateFlags
///
/// In order to support other types, the trait `VMState` must be implemented
/// for them. The macros
-/// [`impl_vmstate_bitsized!`](crate::impl_vmstate_bitsized)
+/// [`impl_vmstate_bitsized!`](crate::impl_vmstate_bitsized),
+/// [`impl_vmstate_struct!`](crate::impl_vmstate_struct),
/// and [`impl_vmstate_forward!`](crate::impl_vmstate_forward) help with this.
#[macro_export]
macro_rules! vmstate_of {
@@ -215,11 +146,6 @@ macro_rules! vmstate_of {
$(field_exists: $crate::vmstate_exist_fn!($struct_name, $test_fn),)?
// The calls to `call_func_with_field!` are the magic that
// computes most of the VMStateField from the type of the field.
- info: $crate::info_enum_to_ref!($crate::call_func_with_field!(
- $crate::vmstate::vmstate_scalar_type,
- $struct_name,
- $field_name
- )),
..$crate::call_func_with_field!(
$crate::vmstate::vmstate_base,
$struct_name,
@@ -320,8 +246,6 @@ macro_rules! impl_vmstate_forward {
// the first field of the tuple
($tuple:ty) => {
unsafe impl $crate::vmstate::VMState for $tuple {
- const SCALAR_TYPE: $crate::vmstate::VMStateFieldType =
- $crate::call_func_with_field!($crate::vmstate::vmstate_scalar_type, $tuple, 0);
const BASE: $crate::bindings::VMStateField =
$crate::call_func_with_field!($crate::vmstate::vmstate_base, $tuple, 0);
}
@@ -333,7 +257,6 @@ unsafe impl $crate::vmstate::VMState for $tuple {
macro_rules! impl_vmstate_transparent {
($type:ty where $base:tt: VMState $($where:tt)*) => {
unsafe impl<$base> VMState for $type where $base: VMState $($where)* {
- const SCALAR_TYPE: VMStateFieldType = <$base as VMState>::SCALAR_TYPE;
const BASE: VMStateField = VMStateField {
size: mem::size_of::<$type>(),
..<$base as VMState>::BASE
@@ -354,10 +277,6 @@ unsafe impl<$base> VMState for $type where $base: VMState $($where)* {
macro_rules! impl_vmstate_bitsized {
($type:ty) => {
unsafe impl $crate::vmstate::VMState for $type {
- const SCALAR_TYPE: $crate::vmstate::VMStateFieldType =
- <<<$type as ::bilge::prelude::Bitsized>::ArbitraryInt
- as ::bilge::prelude::Number>::UnderlyingType
- as $crate::vmstate::VMState>::SCALAR_TYPE;
const BASE: $crate::bindings::VMStateField =
<<<$type as ::bilge::prelude::Bitsized>::ArbitraryInt
as ::bilge::prelude::Number>::UnderlyingType
@@ -375,8 +294,8 @@ unsafe impl $crate::vmstate::VMState for $type {
macro_rules! impl_vmstate_scalar {
($info:ident, $type:ty$(, $varray_flag:ident)?) => {
unsafe impl VMState for $type {
- const SCALAR_TYPE: VMStateFieldType = VMStateFieldType::$info;
const BASE: VMStateField = VMStateField {
+ info: addr_of!(bindings::$info),
size: mem::size_of::<$type>(),
flags: VMStateFlags::VMS_SINGLE,
..Zeroable::ZERO
@@ -397,6 +316,21 @@ unsafe impl VMState for $type {
impl_vmstate_scalar!(vmstate_info_uint64, u64);
impl_vmstate_scalar!(vmstate_info_timer, crate::timer::Timer);
+macro_rules! impl_vmstate_c_struct {
+ ($type:ty, $vmsd:expr) => {
+ unsafe impl VMState for $type {
+ const BASE: VMStateField = $crate::bindings::VMStateField {
+ vmsd: addr_of!($vmsd),
+ size: mem::size_of::<$type>(),
+ flags: VMStateFlags::VMS_STRUCT,
+ ..Zeroable::ZERO
+ };
+ }
+ };
+}
+
+impl_vmstate_c_struct!(qdev::Clock, bindings::vmstate_clock);
+
// Pointer types using the underlying type's VMState plus VMS_POINTER
// Note that references are not supported, though references to cells
// could be allowed.
@@ -404,7 +338,6 @@ unsafe impl VMState for $type {
macro_rules! impl_vmstate_pointer {
($type:ty where $base:tt: VMState $($where:tt)*) => {
unsafe impl<$base> VMState for $type where $base: VMState $($where)* {
- const SCALAR_TYPE: VMStateFieldType = <T as VMState>::SCALAR_TYPE;
const BASE: VMStateField = <$base as VMState>::BASE.with_pointer_flag();
}
};
@@ -423,7 +356,6 @@ unsafe impl<$base> VMState for $type where $base: VMState $($where)* {
// VMS_ARRAY/VMS_ARRAY_OF_POINTER
unsafe impl<T: VMState, const N: usize> VMState for [T; N] {
- const SCALAR_TYPE: VMStateFieldType = <T as VMState>::SCALAR_TYPE;
const BASE: VMStateField = <T as VMState>::BASE.with_array_flag(N);
}
@@ -445,7 +377,7 @@ pub extern "C" fn rust_vms_test_field_exists<T, F: for<'a> FnCall<(&'a T, u8), b
opaque: *mut c_void,
version_id: c_int,
) -> bool {
- // SAFETY: assumes vmstate_struct! is used correctly
+ // SAFETY: the function is used in T's implementation of VMState
let owner: &T = unsafe { &*(opaque.cast::<T>()) };
let version: u8 = version_id.try_into().unwrap();
F::call((owner, version))
@@ -473,76 +405,6 @@ const fn phantom__<T>(_: &T) -> ::core::marker::PhantomData<T> {
}};
}
-// FIXME: including the `vmsd` field in a `const` is not possible without
-// the const_refs_static feature (stabilized in Rust 1.83.0). Without it,
-// it is not possible to use VMS_STRUCT in a transparent manner using
-// `vmstate_of!`. While VMSTATE_CLOCK can at least try to be type-safe,
-// VMSTATE_STRUCT includes $type only for documentation purposes; it
-// is checked against $field_name and $struct_name, but not against $vmsd
-// which is what really would matter.
-#[doc(alias = "VMSTATE_STRUCT")]
-#[macro_export]
-macro_rules! vmstate_struct {
- ($struct_name:ty, $field_name:ident $([0 .. $num:ident $(* $factor:expr)?])?, $vmsd:expr, $type:ty $(, $test_fn:expr)? $(,)?) => {
- $crate::bindings::VMStateField {
- name: ::core::concat!(::core::stringify!($field_name), "\0")
- .as_bytes()
- .as_ptr() as *const ::std::os::raw::c_char,
- $(num_offset: ::std::mem::offset_of!($struct_name, $num),)?
- offset: {
- $crate::assert_field_type!($struct_name, $field_name, $type $(, num = $num)?);
- ::std::mem::offset_of!($struct_name, $field_name)
- },
- size: ::core::mem::size_of::<$type>(),
- flags: $crate::bindings::VMStateFlags::VMS_STRUCT,
- vmsd: $vmsd.as_ref(),
- $(field_exists: $crate::vmstate_exist_fn!($struct_name, $test_fn),)?
- ..$crate::zeroable::Zeroable::ZERO
- } $(.with_varray_flag_unchecked(
- $crate::call_func_with_field!(
- $crate::vmstate::vmstate_varray_flag,
- $struct_name,
- $num
- )
- )
- $(.with_varray_multiply($factor))?)?
- };
-}
-
-#[doc(alias = "VMSTATE_CLOCK")]
-#[macro_export]
-macro_rules! vmstate_clock {
- ($struct_name:ty, $field_name:ident $([0 .. $num:ident $(* $factor:expr)?])?) => {{
- $crate::bindings::VMStateField {
- name: ::core::concat!(::core::stringify!($field_name), "\0")
- .as_bytes()
- .as_ptr() as *const ::std::os::raw::c_char,
- offset: {
- $crate::assert_field_type!(
- $struct_name,
- $field_name,
- $crate::qom::Owned<$crate::qdev::Clock> $(, num = $num)?
- );
- ::std::mem::offset_of!($struct_name, $field_name)
- },
- size: ::core::mem::size_of::<*const $crate::qdev::Clock>(),
- flags: $crate::bindings::VMStateFlags(
- $crate::bindings::VMStateFlags::VMS_STRUCT.0
- | $crate::bindings::VMStateFlags::VMS_POINTER.0,
- ),
- vmsd: unsafe { ::core::ptr::addr_of!($crate::bindings::vmstate_clock) },
- ..$crate::zeroable::Zeroable::ZERO
- } $(.with_varray_flag_unchecked(
- $crate::call_func_with_field!(
- $crate::vmstate::vmstate_varray_flag,
- $struct_name,
- $num
- )
- )
- $(.with_varray_multiply($factor))?)?
- }};
-}
-
/// Helper macro to declare a list of
/// ([`VMStateField`](`crate::bindings::VMStateField`)) into a static and return
/// a pointer to the array of values it created.
@@ -577,6 +439,30 @@ macro_rules! vmstate_validate {
};
}
+/// Helper macro to allow using a struct in [`vmstate_field!`]
+///
+/// # Safety
+///
+/// The [`VMStateDescription`] constant `$vmsd` must be an accurate
+/// description of the struct.
+#[macro_export]
+macro_rules! impl_vmstate_struct {
+ ($type:ty, $vmsd:expr) => {
+ unsafe impl $crate::vmstate::VMState for $type {
+ const BASE: $crate::bindings::VMStateField = {
+ static VMSD: $crate::bindings::VMStateDescription = $vmsd.get();
+
+ $crate::bindings::VMStateField {
+ vmsd: ::core::ptr::addr_of!(VMSD),
+ size: ::core::mem::size_of::<$type>(),
+ flags: $crate::bindings::VMStateFlags::VMS_STRUCT,
+ ..$crate::zeroable::Zeroable::ZERO
+ }
+ };
+ }
+ };
+}
+
/// A transparent wrapper type for the `subsections` field of
/// [`VMStateDescription`].
///
@@ -624,7 +510,7 @@ unsafe impl<T: Sync> Sync for VMStateDescription<T> {}
>(
opaque: *mut c_void,
) -> c_int {
- // SAFETY: assumes vmstate_struct! is used correctly
+ // SAFETY: the function is used in T's implementation of VMState
let result = F::call((unsafe { &*(opaque.cast::<T>()) },));
into_neg_errno(result)
}
@@ -636,7 +522,7 @@ unsafe impl<T: Sync> Sync for VMStateDescription<T> {}
opaque: *mut c_void,
version_id: c_int,
) -> c_int {
- // SAFETY: assumes vmstate_struct! is used correctly
+ // SAFETY: the function is used in T's implementation of VMState
let owner: &T = unsafe { &*(opaque.cast::<T>()) };
let version: u8 = version_id.try_into().unwrap();
let result = F::call((owner, version));
@@ -649,7 +535,7 @@ unsafe impl<T: Sync> Sync for VMStateDescription<T> {}
>(
opaque: *mut c_void,
) -> c_int {
- // SAFETY: assumes vmstate_struct! is used correctly
+ // SAFETY: the function is used in T's implementation of VMState
let result = F::call((unsafe { &*(opaque.cast::<T>()) },));
into_neg_errno(result)
}
@@ -660,7 +546,7 @@ unsafe impl<T: Sync> Sync for VMStateDescription<T> {}
>(
opaque: *mut c_void,
) -> c_int {
- // SAFETY: assumes vmstate_struct! is used correctly
+ // SAFETY: the function is used in T's implementation of VMState
let result = F::call((unsafe { &*(opaque.cast::<T>()) },));
into_neg_errno(result)
}
@@ -668,14 +554,14 @@ unsafe impl<T: Sync> Sync for VMStateDescription<T> {}
unsafe extern "C" fn vmstate_needed_cb<T, F: for<'a> FnCall<(&'a T,), bool>>(
opaque: *mut c_void,
) -> bool {
- // SAFETY: assumes vmstate_struct! is used correctly
+ // SAFETY: the function is used in T's implementation of VMState
F::call((unsafe { &*(opaque.cast::<T>()) },))
}
unsafe extern "C" fn vmstate_dev_unplug_pending_cb<T, F: for<'a> FnCall<(&'a T,), bool>>(
opaque: *mut c_void,
) -> bool {
- // SAFETY: assumes vmstate_struct! is used correctly
+ // SAFETY: the function is used in T's implementation of VMState
F::call((unsafe { &*(opaque.cast::<T>()) },))
}
diff --git a/rust/qemu-api/tests/vmstate_tests.rs b/rust/qemu-api/tests/vmstate_tests.rs
index 12f852ef703..c73dba35fd3 100644
--- a/rust/qemu-api/tests/vmstate_tests.rs
+++ b/rust/qemu-api/tests/vmstate_tests.rs
@@ -15,9 +15,9 @@
vmstate_info_uint64, vmstate_info_uint8, vmstate_info_unused_buffer, VMStateFlags,
},
cell::{BqlCell, Opaque},
- impl_vmstate_forward,
+ impl_vmstate_forward, impl_vmstate_struct,
vmstate::{VMStateDescription, VMStateDescriptionBuilder, VMStateField},
- vmstate_fields, vmstate_of, vmstate_struct, vmstate_unused, vmstate_validate,
+ vmstate_fields, vmstate_of, vmstate_unused, vmstate_validate,
};
const FOO_ARRAY_MAX: usize = 3;
@@ -52,6 +52,8 @@ struct FooA {
})
.build();
+impl_vmstate_struct!(FooA, &VMSTATE_FOOA);
+
#[test]
fn test_vmstate_uint16() {
let foo_fields: &[VMStateField] =
@@ -173,20 +175,19 @@ fn validate_foob(_state: &FooB, _version_id: u8) -> bool {
true
}
-static VMSTATE_FOOB: VMStateDescription<FooB> =
- VMStateDescriptionBuilder::<FooB>::new()
- .name(c"foo_b")
- .version_id(2)
- .minimum_version_id(1)
- .fields(vmstate_fields! {
- vmstate_of!(FooB, val).with_version_id(2),
- vmstate_of!(FooB, wrap),
- vmstate_struct!(FooB, arr_a[0 .. num_a], &VMSTATE_FOOA, FooA).with_version_id(1),
- vmstate_struct!(FooB, arr_a_mul[0 .. num_a_mul * 32], &VMSTATE_FOOA, FooA).with_version_id(2),
- vmstate_of!(FooB, arr_i64),
- vmstate_struct!(FooB, arr_a_wrap[0 .. num_a_wrap], &VMSTATE_FOOA, FooA, validate_foob),
- })
- .build();
+static VMSTATE_FOOB: VMStateDescription<FooB> = VMStateDescriptionBuilder::<FooB>::new()
+ .name(c"foo_b")
+ .version_id(2)
+ .minimum_version_id(1)
+ .fields(vmstate_fields! {
+ vmstate_of!(FooB, val).with_version_id(2),
+ vmstate_of!(FooB, wrap),
+ vmstate_of!(FooB, arr_a[0 .. num_a]).with_version_id(1),
+ vmstate_of!(FooB, arr_a_mul[0 .. num_a_mul * 32]).with_version_id(2),
+ vmstate_of!(FooB, arr_i64),
+ vmstate_of!(FooB, arr_a_wrap[0 .. num_a_wrap], validate_foob),
+ })
+ .build();
#[test]
fn test_vmstate_bool_v() {
@@ -351,9 +352,7 @@ unsafe impl Sync for FooC {}
.minimum_version_id(1)
.fields(vmstate_fields! {
vmstate_of!(FooC, ptr).with_version_id(2),
- // FIXME: Currently vmstate_struct doesn't support the pointer to structure.
- // VMSTATE_STRUCT_POINTER: vmstate_struct!(FooC, ptr_a, VMSTATE_FOOA, NonNull<FooA>)
- vmstate_unused!(size_of::<NonNull<FooA>>()),
+ vmstate_of!(FooC, ptr_a),
vmstate_of!(FooC, arr_ptr),
vmstate_of!(FooC, arr_ptr_wrap),
})
@@ -385,6 +384,31 @@ fn test_vmstate_pointer() {
assert!(foo_fields[0].field_exists.is_none());
}
+#[test]
+fn test_vmstate_struct_pointer() {
+ let foo_fields: &[VMStateField] =
+ unsafe { slice::from_raw_parts(VMSTATE_FOOC.as_ref().fields, 6) };
+
+ // 2st VMStateField ("ptr_a") in VMSTATE_FOOC (corresponding to
+ // VMSTATE_STRUCT_POINTER)
+ assert_eq!(
+ unsafe { CStr::from_ptr(foo_fields[1].name) }.to_bytes_with_nul(),
+ b"ptr\0"
+ );
+ assert_eq!(foo_fields[1].offset, PTR_SIZE);
+ assert_eq!(foo_fields[1].num_offset, 0);
+ assert_eq!(foo_fields[1].vmsd, VMSTATE_FOOA.as_ref());
+ assert_eq!(foo_fields[1].version_id, 0);
+ assert_eq!(foo_fields[1].size, PTR_SIZE);
+ assert_eq!(foo_fields[1].num, 0);
+ assert_eq!(
+ foo_fields[1].flags.0,
+ VMStateFlags::VMS_STRUCT.0 | VMStateFlags::VMS_POINTER.0
+ );
+ assert!(foo_fields[1].info.is_null());
+ assert!(foo_fields[1].field_exists.is_none());
+}
+
#[test]
fn test_vmstate_macro_array_of_pointer() {
let foo_fields: &[VMStateField] =
@@ -444,8 +468,7 @@ fn test_vmstate_macro_array_of_pointer_wrapped() {
// * VMSTATE_FOOD:
// - VMSTATE_VALIDATE
-// Add more member fields when vmstate_of/vmstate_struct support "test"
-// parameter.
+// Add more member fields when vmstate_of support "test" parameter.
struct FooD;
impl FooD {
--
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