Merge tag 'alloc-7.2-rc1' of https://github.com/Rust-for-Linux/linux into rust-next

Pull alloc updates from Danilo Krummrich:

 - Fix the 'Vec::reserve()' doctest to properly account for the existing
   vector length in the capacity assertion.

 - Fix an incorrect operator in the 'Vec::extend_with()' SAFETY comment;
   add a doc test demonstrating basic usage and the zero-length case.

 - Cleanup all imports in the alloc module and its doctests to use the
   "kernel vertical" import style.

* tag 'alloc-7.2-rc1' of https://github.com/Rust-for-Linux/linux:
  rust: alloc: cleanup doctest imports to "kernel vertical" style
  rust: alloc: cleanup imports and use "kernel vertical" style
  rust: alloc: fix `Vec::extend_with` SAFETY comment
  rust: alloc: add doc test for `Vec::extend_with`
  rust: alloc: fix assert in `Vec::reserve` doc test

Author: ojeda

rust/kernel/alloc.rs

@@ -22,8 +22,12 @@ pub use self::kvec::Vec;
 #[derive(Copy, Clone, PartialEq, Eq, Debug)]
 pub struct AllocError;
 
-use crate::error::{code::EINVAL, Result};
-use core::{alloc::Layout, ptr::NonNull};
+use crate::prelude::*;
+
+use core::{
+    alloc::Layout,
+    ptr::NonNull, //
+};
 
 /// Flags to be used when allocating memory.
 ///

rust/kernel/alloc/allocator.rs

@@ -8,14 +8,25 @@
 //!
 //! Reference: <https://docs.kernel.org/core-api/memory-allocation.html>
 
-use super::Flags;
-use core::alloc::Layout;
-use core::ptr;
-use core::ptr::NonNull;
-
-use crate::alloc::{AllocError, Allocator, NumaNode};
-use crate::bindings;
-use crate::page;
+use super::{
+    AllocError,
+    Allocator,
+    Flags,
+    NumaNode, //
+};
+
+use crate::{
+    bindings,
+    page, //
+};
+
+use core::{
+    alloc::Layout,
+    ptr::{
+        self,
+        NonNull, //
+    }, //
+};
 
 const ARCH_KMALLOC_MINALIGN: usize = bindings::ARCH_KMALLOC_MINALIGN;
 
@@ -163,8 +174,11 @@ impl Vmalloc {
     /// # Examples
     ///
     /// ```
-    /// # use core::ptr::{NonNull, from_mut};
-    /// # use kernel::{page, prelude::*};
+    /// # use core::ptr::{
+    /// #     from_mut,
+    /// #     NonNull, //
+    /// # };
+    /// # use kernel::page;
     /// use kernel::alloc::allocator::Vmalloc;
     ///
     /// let mut vbox = VBox::<[u8; page::PAGE_SIZE]>::new_uninit(GFP_KERNEL)?;

rust/kernel/alloc/allocator/iter.rs

@@ -1,9 +1,13 @@
 // SPDX-License-Identifier: GPL-2.0
 
 use super::Vmalloc;
+
 use crate::page;
-use core::marker::PhantomData;
-use core::ptr::NonNull;
+
+use core::{
+    marker::PhantomData,
+    ptr::NonNull, //
+};
 
 /// An [`Iterator`] of [`page::BorrowedPage`] items owned by a [`Vmalloc`] allocation.
 ///

rust/kernel/alloc/kbox.rs

@@ -3,24 +3,47 @@
 //! Implementation of [`Box`].
 
 #[allow(unused_imports)] // Used in doc comments.
-use super::allocator::{KVmalloc, Kmalloc, Vmalloc, VmallocPageIter};
-use super::{AllocError, Allocator, Flags, NumaNode};
-use core::alloc::Layout;
-use core::borrow::{Borrow, BorrowMut};
-use core::marker::PhantomData;
-use core::mem::ManuallyDrop;
-use core::mem::MaybeUninit;
-use core::ops::{Deref, DerefMut};
-use core::pin::Pin;
-use core::ptr::NonNull;
-use core::result::Result;
-
-use crate::ffi::c_void;
-use crate::fmt;
-use crate::init::InPlaceInit;
-use crate::page::AsPageIter;
-use crate::types::ForeignOwnable;
-use pin_init::{InPlaceWrite, Init, PinInit, ZeroableOption};
+use super::allocator::{
+    KVmalloc,
+    Kmalloc,
+    Vmalloc,
+    VmallocPageIter, //
+};
+
+use super::{
+    AllocError,
+    Allocator,
+    Flags,
+    NumaNode, //
+};
+
+use crate::{
+    fmt,
+    page::AsPageIter,
+    prelude::*,
+    types::ForeignOwnable, //
+};
+
+use core::{
+    alloc::Layout,
+    borrow::{
+        Borrow,
+        BorrowMut, //
+    },
+    marker::PhantomData,
+    mem::{
+        ManuallyDrop,
+        MaybeUninit, //
+    },
+    ops::{
+        Deref,
+        DerefMut, //
+    },
+    ptr::NonNull,
+    result::Result, //
+};
+
+use pin_init::ZeroableOption;
 
 /// The kernel's [`Box`] type -- a heap allocation for a single value of type `T`.
 ///
@@ -274,7 +297,10 @@ where
     /// # Examples
     ///
     /// ```
-    /// use kernel::sync::{new_spinlock, SpinLock};
+    /// use kernel::sync::{
+    ///     new_spinlock,
+    ///     SpinLock, //
+    /// };
     ///
     /// struct Inner {
     ///     a: u32,
@@ -567,7 +593,6 @@ where
 ///
 /// ```
 /// # use core::borrow::Borrow;
-/// # use kernel::alloc::KBox;
 /// struct Foo<B: Borrow<u32>>(B);
 ///
 /// // Owned instance.
@@ -595,7 +620,6 @@ where
 ///
 /// ```
 /// # use core::borrow::BorrowMut;
-/// # use kernel::alloc::KBox;
 /// struct Foo<B: BorrowMut<u32>>(B);
 ///
 /// // Owned instance.
@@ -660,9 +684,13 @@ where
 /// # Examples
 ///
 /// ```
-/// # use kernel::prelude::*;
-/// use kernel::alloc::allocator::VmallocPageIter;
-/// use kernel::page::{AsPageIter, PAGE_SIZE};
+/// use kernel::{
+///     alloc::allocator::VmallocPageIter,
+///     page::{
+///         AsPageIter,
+///         PAGE_SIZE, //
+///     }, //
+/// };
 ///
 /// let mut vbox = VBox::new((), GFP_KERNEL)?;
 ///

rust/kernel/alloc/kvec.rs

@@ -3,29 +3,52 @@
 //! Implementation of [`Vec`].
 
 use super::{
-    allocator::{KVmalloc, Kmalloc, Vmalloc, VmallocPageIter},
+    allocator::{
+        KVmalloc,
+        Kmalloc,
+        Vmalloc,
+        VmallocPageIter, //
+    },
     layout::ArrayLayout,
-    AllocError, Allocator, Box, Flags, NumaNode,
+    AllocError,
+    Allocator,
+    Box,
+    Flags,
+    NumaNode, //
 };
+
 use crate::{
     fmt,
     page::{
         AsPageIter,
         PAGE_SIZE, //
-    },
+    }, //
 };
+
 use core::{
-    borrow::{Borrow, BorrowMut},
+    borrow::{
+        Borrow,
+        BorrowMut, //
+    },
     marker::PhantomData,
-    mem::{ManuallyDrop, MaybeUninit},
-    ops::Deref,
-    ops::DerefMut,
-    ops::Index,
-    ops::IndexMut,
-    ptr,
-    ptr::NonNull,
-    slice,
-    slice::SliceIndex,
+    mem::{
+        ManuallyDrop,
+        MaybeUninit, //
+    },
+    ops::{
+        Deref,
+        DerefMut,
+        Index,
+        IndexMut, //
+    },
+    ptr::{
+        self,
+        NonNull, //
+    },
+    slice::{
+        self,
+        SliceIndex, //
+    }, //
 };
 
 mod errors;
@@ -614,7 +637,7 @@ where
     ///
     /// v.reserve(10, GFP_KERNEL)?;
     /// let cap = v.capacity();
-    /// assert!(cap >= 10);
+    /// assert!(cap >= v.len() + 10);
     ///
     /// v.reserve(10, GFP_KERNEL)?;
     /// let new_cap = v.capacity();
@@ -849,6 +872,24 @@ impl<T> Vec<T, KVmalloc> {
 
 impl<T: Clone, A: Allocator> Vec<T, A> {
     /// Extend the vector by `n` clones of `value`.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// let mut v = KVec::new();
+    /// v.push(1, GFP_KERNEL)?;
+    ///
+    /// v.extend_with(3, 5, GFP_KERNEL)?;
+    /// assert_eq!(&v, &[1, 5, 5, 5]);
+    ///
+    /// v.extend_with(2, 8, GFP_KERNEL)?;
+    /// assert_eq!(&v, &[1, 5, 5, 5, 8, 8]);
+    ///
+    /// v.extend_with(0, 3, GFP_KERNEL)?;
+    /// assert_eq!(&v, &[1, 5, 5, 5, 8, 8]);
+    ///
+    /// # Ok::<(), Error>(())
+    /// ```
     pub fn extend_with(&mut self, n: usize, value: T, flags: Flags) -> Result<(), AllocError> {
         if n == 0 {
             return Ok(());
@@ -866,7 +907,7 @@ impl<T: Clone, A: Allocator> Vec<T, A> {
         spare[n - 1].write(value);
 
         // SAFETY:
-        // - `self.len() + n < self.capacity()` due to the call to reserve above,
+        // - `self.len() + n <= self.capacity()` due to the call to reserve above,
         // - the loop and the line above initialized the next `n` elements.
         unsafe { self.inc_len(n) };
 
@@ -1146,9 +1187,13 @@ where
 /// # Examples
 ///
 /// ```
-/// # use kernel::prelude::*;
-/// use kernel::alloc::allocator::VmallocPageIter;
-/// use kernel::page::{AsPageIter, PAGE_SIZE};
+/// use kernel::{
+///     alloc::allocator::VmallocPageIter,
+///     page::{
+///         AsPageIter,
+///         PAGE_SIZE, //
+///     }, //
+/// };
 ///
 /// let mut vec = VVec::<u8>::new();
 ///

rust/kernel/alloc/kvec/errors.rs

@@ -2,8 +2,10 @@
 
 //! Errors for the [`Vec`] type.
 
-use kernel::fmt;
-use kernel::prelude::*;
+use crate::{
+    fmt,
+    prelude::*, //
+};
 
 /// Error type for [`Vec::push_within_capacity`].
 pub struct PushError<T>(pub T);

rust/kernel/alloc/layout.rs

@@ -4,7 +4,10 @@
 //!
 //! Custom layout types extending or improving [`Layout`].
 
-use core::{alloc::Layout, marker::PhantomData};
+use core::{
+    alloc::Layout,
+    marker::PhantomData, //
+};
 
 /// Error when constructing an [`ArrayLayout`].
 pub struct LayoutError;
@@ -47,7 +50,10 @@ impl<T> ArrayLayout<T> {
     /// # Examples
     ///
     /// ```
-    /// # use kernel::alloc::layout::{ArrayLayout, LayoutError};
+    /// # use kernel::alloc::layout::{
+    /// #     ArrayLayout,
+    /// #     LayoutError, //
+    /// # };
     /// let layout = ArrayLayout::<i32>::new(15)?;
     /// assert_eq!(layout.len(), 15);
     ///