[PATCH v6 17/18] rust: pin-init: refactor to use `&raw mut`

[Antonio Hickey <contact@antoniohickey.com>]

Replacing all occurrences of `addr_of_mut!(place)`
with `&raw mut place`.

This will allow us to reduce macro complexity, and improve consistency
with existing reference syntax as `&raw mut` is similar to `&mut`
making it fit more naturally with other existing code.

Suggested-by: Benno Lossin <benno.lossin@proton.me>
Link: https://github.com/Rust-for-Linux/linux/issues/1148
Signed-off-by: Antonio Hickey <contact@antoniohickey.com>
---
 rust/pin-init/README.md     |  3 +--
 rust/pin-init/src/lib.rs    |  7 +++----
 rust/pin-init/src/macros.rs | 16 ++++++++--------
 3 files changed, 12 insertions(+), 14 deletions(-)

diff --git a/rust/pin-init/README.md b/rust/pin-init/README.md
index 3d04796b212b..1ab4ad0144f3 100644
--- a/rust/pin-init/README.md
+++ b/rust/pin-init/README.md
@@ -142,7 +142,6 @@ actually does the initialization in the correct way. Here are the things to look
 ```rust
 use pin_init::{pin_data, pinned_drop, PinInit, PinnedDrop, pin_init_from_closure};
 use core::{
-    ptr::addr_of_mut,
     marker::PhantomPinned,
     cell::UnsafeCell,
     pin::Pin,
@@ -181,7 +180,7 @@ impl RawFoo {
         unsafe {
             pin_init_from_closure(move |slot: *mut Self| {
                 // `slot` contains uninit memory, avoid creating a reference.
-                let foo = addr_of_mut!((*slot).foo);
+                let foo = &raw mut (*slot).foo;
                 let foo = UnsafeCell::raw_get(foo).cast::<bindings::foo>();
 
                 // Initialize the `foo`
diff --git a/rust/pin-init/src/lib.rs b/rust/pin-init/src/lib.rs
index 05c44514765e..36391738835c 100644
--- a/rust/pin-init/src/lib.rs
+++ b/rust/pin-init/src/lib.rs
@@ -166,7 +166,6 @@
 //! # #![feature(extern_types)]
 //! use pin_init::{pin_data, pinned_drop, PinInit, PinnedDrop, pin_init_from_closure};
 //! use core::{
-//!     ptr::addr_of_mut,
 //!     marker::PhantomPinned,
 //!     cell::UnsafeCell,
 //!     pin::Pin,
@@ -205,7 +204,7 @@
 //!         unsafe {
 //!             pin_init_from_closure(move |slot: *mut Self| {
 //!                 // `slot` contains uninit memory, avoid creating a reference.
-//!                 let foo = addr_of_mut!((*slot).foo);
+//!                 let foo = &raw mut (*slot).foo;
 //!                 let foo = UnsafeCell::raw_get(foo).cast::<bindings::foo>();
 //!
 //!                 // Initialize the `foo`
@@ -698,7 +697,7 @@ macro_rules! stack_try_pin_init {
 ///
 /// ```rust
 /// # use pin_init::*;
-/// # use core::{ptr::addr_of_mut, marker::PhantomPinned};
+/// # use core::marker::PhantomPinned;
 /// #[pin_data]
 /// #[derive(Zeroable)]
 /// struct Buf {
@@ -712,7 +711,7 @@ macro_rules! stack_try_pin_init {
 /// let init = pin_init!(&this in Buf {
 ///     buf: [0; 64],
 ///     // SAFETY: TODO.
-///     ptr: unsafe { addr_of_mut!((*this.as_ptr()).buf).cast() },
+///     ptr: unsafe { (&raw mut (*this.as_ptr()).buf).cast() },
 ///     pin: PhantomPinned,
 /// });
 /// let init = pin_init!(Buf {
diff --git a/rust/pin-init/src/macros.rs b/rust/pin-init/src/macros.rs
index 28a91a1e1218..14ab121443f0 100644
--- a/rust/pin-init/src/macros.rs
+++ b/rust/pin-init/src/macros.rs
@@ -251,7 +251,7 @@
 //!                     // is an error later. This `DropGuard` will drop the field when it gets
 //!                     // dropped and has not yet been forgotten.
 //!                     let __t_guard = unsafe {
-//!                         ::pin_init::__internal::DropGuard::new(::core::addr_of_mut!((*slot).t))
+//!                         ::pin_init::__internal::DropGuard::new(&raw mut (*slot).t)
 //!                     };
 //!                     // Expansion of `x: 0,`:
 //!                     // Since this can be an arbitrary expression we cannot place it inside
@@ -262,7 +262,7 @@
 //!                     }
 //!                     // We again create a `DropGuard`.
 //!                     let __x_guard = unsafe {
-//!                         ::pin_init::__internal::DropGuard::new(::core::addr_of_mut!((*slot).x))
+//!                         ::pin_init::__internal::DropGuard::new(&raw mut (*slot).x)
 //!                     };
 //!                     // Since initialization has successfully completed, we can now forget
 //!                     // the guards. This is not `mem::forget`, since we only have
@@ -462,12 +462,12 @@
 //!                 unsafe { ::core::ptr::write(&raw mut (*slot).a, a) };
 //!             }
 //!             let __a_guard = unsafe {
-//!                 ::pin_init::__internal::DropGuard::new(::core::addr_of_mut!((*slot).a))
+//!                 ::pin_init::__internal::DropGuard::new(&raw mut (*slot).a)
 //!             };
 //!             let init = Bar::new(36);
 //!             unsafe { data.b(&raw mut (*slot).b, b)? };
 //!             let __b_guard = unsafe {
-//!                 ::pin_init::__internal::DropGuard::new(::core::addr_of_mut!((*slot).b))
+//!                 ::pin_init::__internal::DropGuard::new(&raw mut (*slot).b)
 //!             };
 //!             ::core::mem::forget(__b_guard);
 //!             ::core::mem::forget(__a_guard);
@@ -1223,7 +1223,7 @@ fn assert_zeroable<T: $crate::Zeroable>(_: *mut T) {}
         $crate::macros::paste! {
             // SAFETY: We forget the guard later when initialization has succeeded.
             let [< __ $field _guard >] = unsafe {
-                $crate::__internal::DropGuard::new(::core::ptr::addr_of_mut!((*$slot).$field))
+                $crate::__internal::DropGuard::new(&raw mut (*$slot).$field)
             };
 
             $crate::__init_internal!(init_slot($use_data):
@@ -1246,7 +1246,7 @@ fn assert_zeroable<T: $crate::Zeroable>(_: *mut T) {}
         //
         // SAFETY: `slot` is valid, because we are inside of an initializer closure, we
         // return when an error/panic occurs.
-        unsafe { $crate::Init::__init(init, ::core::ptr::addr_of_mut!((*$slot).$field))? };
+        unsafe { $crate::Init::__init(init, &raw mut (*$slot).$field)? };
         // Create the drop guard:
         //
         // We rely on macro hygiene to make it impossible for users to access this local variable.
@@ -1254,7 +1254,7 @@ fn assert_zeroable<T: $crate::Zeroable>(_: *mut T) {}
         $crate::macros::paste! {
             // SAFETY: We forget the guard later when initialization has succeeded.
             let [< __ $field _guard >] = unsafe {
-                $crate::__internal::DropGuard::new(::core::ptr::addr_of_mut!((*$slot).$field))
+                $crate::__internal::DropGuard::new(&raw mut (*$slot).$field)
             };
 
             $crate::__init_internal!(init_slot():
@@ -1286,7 +1286,7 @@ fn assert_zeroable<T: $crate::Zeroable>(_: *mut T) {}
         $crate::macros::paste! {
             // SAFETY: We forget the guard later when initialization has succeeded.
             let [< __ $field _guard >] = unsafe {
-                $crate::__internal::DropGuard::new(::core::ptr::addr_of_mut!((*$slot).$field))
+                $crate::__internal::DropGuard::new(&raw mut (*$slot).$field)
             };
 
             $crate::__init_internal!(init_slot($($use_data)?):
-- 
2.48.1