Merge patch series "Rust support for `struct iov_iter`"

Alice Ryhl <aliceryhl@google.com> says:

This series adds support for the `struct iov_iter` type. This type
represents an IO buffer for reading or writing, and can be configured
for either direction of communication.

In Rust, we define separate types for reading and writing. This will
ensure that you cannot mix them up and e.g. call copy_from_iter in a
read_iter syscall.

To use the new abstractions, miscdevices are given new methods read_iter
and write_iter that can be used to implement the read/write syscalls on
a miscdevice. The miscdevice sample is updated to provide read/write
operations.

Intended for Greg's miscdevice tree.

Link: https://lore.kernel.org/r/20250822-iov-iter-v5-0-6ce4819c2977@google.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>