From: Marc-André Lureau <marcandre.lureau@redhat.com>
This will allow to split vmstate to a standalone crate next.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
rust/qemu-api/src/cell.rs | 5 ++++-
rust/qemu-api/src/vmstate.rs | 16 +++++++---------
2 files changed, 11 insertions(+), 10 deletions(-)
diff --git a/rust/qemu-api/src/cell.rs b/rust/qemu-api/src/cell.rs
index 98d720caf9..4bce526e45 100644
--- a/rust/qemu-api/src/cell.rs
+++ b/rust/qemu-api/src/cell.rs
@@ -152,7 +152,7 @@
ptr::NonNull,
};
-use crate::bindings;
+use crate::{bindings, impl_vmstate_transparent};
/// An internal function that is used by doctests.
pub fn bql_start_test() {
@@ -866,3 +866,6 @@ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
(**self).fmt(f)
}
}
+
+impl_vmstate_transparent!(BqlCell<T> where T: VMState);
+impl_vmstate_transparent!(BqlRefCell<T> where T: VMState);
diff --git a/rust/qemu-api/src/vmstate.rs b/rust/qemu-api/src/vmstate.rs
index c1e2b06390..9d33997c57 100644
--- a/rust/qemu-api/src/vmstate.rs
+++ b/rust/qemu-api/src/vmstate.rs
@@ -29,8 +29,7 @@
use common::{callbacks::FnCall, Zeroable};
-use crate::bindings::VMStateFlags;
-pub use crate::bindings::{VMStateDescription, VMStateField};
+pub use crate::bindings::{VMStateDescription, VMStateField, VMStateFlags};
/// This macro is used to call a function with a generic argument bound
/// to the type of a field. The function must take a
@@ -325,15 +324,16 @@ unsafe impl $crate::vmstate::VMState for $tuple {
// Transparent wrappers: just use the internal type
+#[macro_export]
macro_rules! impl_vmstate_transparent {
($type:ty where $base:tt: VMState $($where:tt)*) => {
- unsafe impl<$base> VMState for $type where $base: VMState $($where)* {
- const SCALAR_TYPE: VMStateFieldType = <$base as VMState>::SCALAR_TYPE;
- const BASE: VMStateField = VMStateField {
+ unsafe impl<$base> $crate::vmstate::VMState for $type where $base: $crate::vmstate::VMState $($where)* {
+ const SCALAR_TYPE: $crate::vmstate::VMStateFieldType = <$base as $crate::vmstate::VMState>::SCALAR_TYPE;
+ const BASE: $crate::vmstate::VMStateField = $crate::vmstate::VMStateField {
size: mem::size_of::<$type>(),
- ..<$base as VMState>::BASE
+ ..<$base as $crate::vmstate::VMState>::BASE
};
- const VARRAY_FLAG: VMStateFlags = <$base as VMState>::VARRAY_FLAG;
+ const VARRAY_FLAG: $crate::vmstate::VMStateFlags = <$base as $crate::vmstate::VMState>::VARRAY_FLAG;
}
};
}
@@ -341,8 +341,6 @@ unsafe impl<$base> VMState for $type where $base: VMState $($where)* {
impl_vmstate_transparent!(std::cell::Cell<T> where T: VMState);
impl_vmstate_transparent!(std::cell::UnsafeCell<T> where T: VMState);
impl_vmstate_transparent!(std::pin::Pin<T> where T: VMState);
-impl_vmstate_transparent!(crate::cell::BqlCell<T> where T: VMState);
-impl_vmstate_transparent!(crate::cell::BqlRefCell<T> where T: VMState);
impl_vmstate_transparent!(::common::Opaque<T> where T: VMState);
#[macro_export]
--
2.50.1
On 8/26/25 16:04, marcandre.lureau@redhat.com wrote:
> From: Marc-André Lureau <marcandre.lureau@redhat.com>
>
> This will allow to split vmstate to a standalone crate next.
Can you explain why this is needed? Could "migration" depend on "bql"
(or even, "bql" could stay in util), and keep the implementation of
VMState for cells, just like you do for Opaque?
Thanks,
Paolo
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> ---
> rust/qemu-api/src/cell.rs | 5 ++++-
> rust/qemu-api/src/vmstate.rs | 16 +++++++---------
> 2 files changed, 11 insertions(+), 10 deletions(-)
>
> diff --git a/rust/qemu-api/src/cell.rs b/rust/qemu-api/src/cell.rs
> index 98d720caf9..4bce526e45 100644
> --- a/rust/qemu-api/src/cell.rs
> +++ b/rust/qemu-api/src/cell.rs
> @@ -152,7 +152,7 @@
> ptr::NonNull,
> };
>
> -use crate::bindings;
> +use crate::{bindings, impl_vmstate_transparent};
>
> /// An internal function that is used by doctests.
> pub fn bql_start_test() {
> @@ -866,3 +866,6 @@ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
> (**self).fmt(f)
> }
> }
> +
> +impl_vmstate_transparent!(BqlCell<T> where T: VMState);
> +impl_vmstate_transparent!(BqlRefCell<T> where T: VMState);
> diff --git a/rust/qemu-api/src/vmstate.rs b/rust/qemu-api/src/vmstate.rs
> index c1e2b06390..9d33997c57 100644
> --- a/rust/qemu-api/src/vmstate.rs
> +++ b/rust/qemu-api/src/vmstate.rs
> @@ -29,8 +29,7 @@
>
> use common::{callbacks::FnCall, Zeroable};
>
> -use crate::bindings::VMStateFlags;
> -pub use crate::bindings::{VMStateDescription, VMStateField};
> +pub use crate::bindings::{VMStateDescription, VMStateField, VMStateFlags};
>
> /// This macro is used to call a function with a generic argument bound
> /// to the type of a field. The function must take a
> @@ -325,15 +324,16 @@ unsafe impl $crate::vmstate::VMState for $tuple {
>
> // Transparent wrappers: just use the internal type
>
> +#[macro_export]
> macro_rules! impl_vmstate_transparent {
> ($type:ty where $base:tt: VMState $($where:tt)*) => {
> - unsafe impl<$base> VMState for $type where $base: VMState $($where)* {
> - const SCALAR_TYPE: VMStateFieldType = <$base as VMState>::SCALAR_TYPE;
> - const BASE: VMStateField = VMStateField {
> + unsafe impl<$base> $crate::vmstate::VMState for $type where $base: $crate::vmstate::VMState $($where)* {
> + const SCALAR_TYPE: $crate::vmstate::VMStateFieldType = <$base as $crate::vmstate::VMState>::SCALAR_TYPE;
> + const BASE: $crate::vmstate::VMStateField = $crate::vmstate::VMStateField {
> size: mem::size_of::<$type>(),
> - ..<$base as VMState>::BASE
> + ..<$base as $crate::vmstate::VMState>::BASE
> };
> - const VARRAY_FLAG: VMStateFlags = <$base as VMState>::VARRAY_FLAG;
> + const VARRAY_FLAG: $crate::vmstate::VMStateFlags = <$base as $crate::vmstate::VMState>::VARRAY_FLAG;
> }
> };
> }
> @@ -341,8 +341,6 @@ unsafe impl<$base> VMState for $type where $base: VMState $($where)* {
> impl_vmstate_transparent!(std::cell::Cell<T> where T: VMState);
> impl_vmstate_transparent!(std::cell::UnsafeCell<T> where T: VMState);
> impl_vmstate_transparent!(std::pin::Pin<T> where T: VMState);
> -impl_vmstate_transparent!(crate::cell::BqlCell<T> where T: VMState);
> -impl_vmstate_transparent!(crate::cell::BqlRefCell<T> where T: VMState);
> impl_vmstate_transparent!(::common::Opaque<T> where T: VMState);
>
> #[macro_export]
Hi
On Tue, Aug 26, 2025 at 10:28 PM Paolo Bonzini <pbonzini@redhat.com> wrote:
> On 8/26/25 16:04, marcandre.lureau@redhat.com wrote:
> > From: Marc-André Lureau <marcandre.lureau@redhat.com>
> >
> > This will allow to split vmstate to a standalone crate next.
>
> Can you explain why this is needed? Could "migration" depend on "bql"
> (or even, "bql" could stay in util), and keep the implementation of
> VMState for cells, just like you do for Opaque?
>
vmstate doesn't require bql. Why should we enforce it at rust level?
If we merge bql in util, then sure we can make vmstate keep the VMState
impl for BqlCells. But why should we do that? To save one crate? I think it
will more future proof if we have a lower-level util crate without bql, and
higher-level crates that rely on it. Perhaps "bql" should be renamed though
(qemu-loop/iothread or something?)
>
> Thanks,
>
> Paolo
>
> > Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> > ---
> > rust/qemu-api/src/cell.rs | 5 ++++-
> > rust/qemu-api/src/vmstate.rs | 16 +++++++---------
> > 2 files changed, 11 insertions(+), 10 deletions(-)
> >
> > diff --git a/rust/qemu-api/src/cell.rs b/rust/qemu-api/src/cell.rs
> > index 98d720caf9..4bce526e45 100644
> > --- a/rust/qemu-api/src/cell.rs
> > +++ b/rust/qemu-api/src/cell.rs
> > @@ -152,7 +152,7 @@
> > ptr::NonNull,
> > };
> >
> > -use crate::bindings;
> > +use crate::{bindings, impl_vmstate_transparent};
> >
> > /// An internal function that is used by doctests.
> > pub fn bql_start_test() {
> > @@ -866,3 +866,6 @@ fn fmt(&self, f: &mut fmt::Formatter<'_>) ->
> fmt::Result {
> > (**self).fmt(f)
> > }
> > }
> > +
> > +impl_vmstate_transparent!(BqlCell<T> where T: VMState);
> > +impl_vmstate_transparent!(BqlRefCell<T> where T: VMState);
> > diff --git a/rust/qemu-api/src/vmstate.rs b/rust/qemu-api/src/vmstate.rs
> > index c1e2b06390..9d33997c57 100644
> > --- a/rust/qemu-api/src/vmstate.rs
> > +++ b/rust/qemu-api/src/vmstate.rs
> > @@ -29,8 +29,7 @@
> >
> > use common::{callbacks::FnCall, Zeroable};
> >
> > -use crate::bindings::VMStateFlags;
> > -pub use crate::bindings::{VMStateDescription, VMStateField};
> > +pub use crate::bindings::{VMStateDescription, VMStateField,
> VMStateFlags};
> >
> > /// This macro is used to call a function with a generic argument bound
> > /// to the type of a field. The function must take a
> > @@ -325,15 +324,16 @@ unsafe impl $crate::vmstate::VMState for $tuple {
> >
> > // Transparent wrappers: just use the internal type
> >
> > +#[macro_export]
> > macro_rules! impl_vmstate_transparent {
> > ($type:ty where $base:tt: VMState $($where:tt)*) => {
> > - unsafe impl<$base> VMState for $type where $base: VMState
> $($where)* {
> > - const SCALAR_TYPE: VMStateFieldType = <$base as
> VMState>::SCALAR_TYPE;
> > - const BASE: VMStateField = VMStateField {
> > + unsafe impl<$base> $crate::vmstate::VMState for $type where
> $base: $crate::vmstate::VMState $($where)* {
> > + const SCALAR_TYPE: $crate::vmstate::VMStateFieldType =
> <$base as $crate::vmstate::VMState>::SCALAR_TYPE;
> > + const BASE: $crate::vmstate::VMStateField =
> $crate::vmstate::VMStateField {
> > size: mem::size_of::<$type>(),
> > - ..<$base as VMState>::BASE
> > + ..<$base as $crate::vmstate::VMState>::BASE
> > };
> > - const VARRAY_FLAG: VMStateFlags = <$base as
> VMState>::VARRAY_FLAG;
> > + const VARRAY_FLAG: $crate::vmstate::VMStateFlags = <$base
> as $crate::vmstate::VMState>::VARRAY_FLAG;
> > }
> > };
> > }
> > @@ -341,8 +341,6 @@ unsafe impl<$base> VMState for $type where $base:
> VMState $($where)* {
> > impl_vmstate_transparent!(std::cell::Cell<T> where T: VMState);
> > impl_vmstate_transparent!(std::cell::UnsafeCell<T> where T: VMState);
> > impl_vmstate_transparent!(std::pin::Pin<T> where T: VMState);
> > -impl_vmstate_transparent!(crate::cell::BqlCell<T> where T: VMState);
> > -impl_vmstate_transparent!(crate::cell::BqlRefCell<T> where T: VMState);
> > impl_vmstate_transparent!(::common::Opaque<T> where T: VMState);
> >
> > #[macro_export]
>
>
On 8/26/25 21:06, Marc-André Lureau wrote: > Hi > > On Tue, Aug 26, 2025 at 10:28 PM Paolo Bonzini <pbonzini@redhat.com > <mailto:pbonzini@redhat.com>> wrote: > > On 8/26/25 16:04, marcandre.lureau@redhat.com > <mailto:marcandre.lureau@redhat.com> wrote: > > From: Marc-André Lureau <marcandre.lureau@redhat.com > <mailto:marcandre.lureau@redhat.com>> > > > > This will allow to split vmstate to a standalone crate next. > > Can you explain why this is needed? Could "migration" depend on "bql" > (or even, "bql" could stay in util), and keep the implementation of > VMState for cells, just like you do for Opaque? > > > vmstate doesn't require bql. Why should we enforce it at rust level? In some sense it does: pre_load/post_load/pre_save/post_save run inside the BQL. It doesn't require it at the language level, but it does at the conceptual level. Anyhow the code is fine, I just wanted to understand if there was something else. > If we merge bql in util, then sure we can make vmstate keep the VMState > impl for BqlCells. But why should we do that? To save one crate? I think > it will more future proof if we have a lower-level util crate without > bql, and higher-level crates that rely on it. Perhaps "bql" should be > renamed though (qemu-loop/iothread or something?) I'm okay with keeping bql separate, no problem. event_loop is also okay as the name. Paolo
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