rust: alloc: implement `IntoIterator` for `Vec`

commit 1d1d223aa3b37c34271aefc2706340d0843bfcb2 upstream.

Implement `IntoIterator` for `Vec`, `Vec`'s `IntoIter` type, as well as
`Iterator` for `IntoIter`.

`Vec::into_iter` disassembles the `Vec` into its raw parts; additionally,
`IntoIter` keeps track of a separate pointer, which is incremented
correspondingly as the iterator advances, while the length, or the count
of elements, is decremented.

This also means that `IntoIter` takes the ownership of the backing
buffer and is responsible to drop the remaining elements and free the
backing buffer, if it's dropped.

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-18-dakr@kernel.org
[ Fixed typos. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/rust/kernel/alloc.rs b/rust/kernel/alloc.rs
index 7f654b214ec2..86d2077a8e64 100644
--- a/rust/kernel/alloc.rs
+++ b/rust/kernel/alloc.rs
@@ -20,6 +20,7 @@ pub use self::kbox::KBox;
 pub use self::kbox::KVBox;
 pub use self::kbox::VBox;
 
+pub use self::kvec::IntoIter;
 pub use self::kvec::KVVec;
 pub use self::kvec::KVec;
 pub use self::kvec::VVec;