Re: [PATCH] rust: pl011: convert pl011_create to safe Rust

[Zhao Liu]

On Thu, Feb 06, 2025 at 12:15:14PM +0100, Paolo Bonzini wrote:
> Date: Thu,  6 Feb 2025 12:15:14 +0100
> From: Paolo Bonzini <pbonzini@redhat.com>
> Subject: [PATCH] rust: pl011: convert pl011_create to safe Rust
> X-Mailer: git-send-email 2.48.1
> 
> Not a major change but, as a small but significant step in creating
> qdev bindings, show how pl011_create can be written without "unsafe"
> calls (apart from converting pointers to references).
> 
> This also provides a starting point for creating Error** bindings.
> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>  rust/hw/char/pl011/src/device.rs | 39 ++++++++++++++++----------------
>  rust/qemu-api/src/sysbus.rs      | 34 +++++++++++++++++++++++++---
>  2 files changed, 50 insertions(+), 23 deletions(-)

...

> +    fn realize(&self) {

What about renaming this as "realize_with_sysbus"?

Elsewhere, the device's own realize method is often used to set
DeviceImpl::REALIZE.

And this realize here is meant to call the realize() method defined on
the C side, so to avoid confusion we can avoid the same name? It's up to
you.

> +        // TODO: return an Error
> +        assert!(bql_locked());
> +        unsafe {
> +            bindings::sysbus_realize(self.as_mut_ptr(), 
> addr_of_mut!(bindings::error_fatal));
> +        }
> +    }

This is a nice patch that shows more about how to use Owned<>!

(BTW, I guess this patch is not the stable material. :-) )

Reviewed-by: Zhao Liu <zhao1.liu@intel.com>