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diff --git a/rust/kernel/block/mq.rs b/rust/kernel/block/mq.rs
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+// SPDX-License-Identifier: GPL-2.0
+
+//! This module provides types for implementing block drivers that interface the
+//! blk-mq subsystem.
+//!
+//! To implement a block device driver, a Rust module must do the following:
+//!
+//! - Implement [`Operations`] for a type `T`.
+//! - Create a [`TagSet<T>`].
+//! - Create a [`GenDisk<T>`], via the [`GenDiskBuilder`].
+//! - Add the disk to the system by calling [`GenDiskBuilder::build`] passing in
+//!   the `TagSet` reference.
+//!
+//! The types available in this module that have direct C counterparts are:
+//!
+//! - The [`TagSet`] type that abstracts the C type `struct tag_set`.
+//! - The [`GenDisk`] type that abstracts the C type `struct gendisk`.
+//! - The [`Request`] type that abstracts the C type `struct request`.
+//!
+//! The kernel will interface with the block device driver by calling the method
+//! implementations of the `Operations` trait.
+//!
+//! IO requests are passed to the driver as [`kernel::types::ARef<Request>`]
+//! instances. The `Request` type is a wrapper around the C `struct request`.
+//! The driver must mark end of processing by calling one of the
+//! `Request::end`, methods. Failure to do so can lead to deadlock or timeout
+//! errors. Please note that the C function `blk_mq_start_request` is implicitly
+//! called when the request is queued with the driver.
+//!
+//! The `TagSet` is responsible for creating and maintaining a mapping between
+//! `Request`s and integer ids as well as carrying a pointer to the vtable
+//! generated by `Operations`. This mapping is useful for associating
+//! completions from hardware with the correct `Request` instance. The `TagSet`
+//! determines the maximum queue depth by setting the number of `Request`
+//! instances available to the driver, and it determines the number of queues to
+//! instantiate for the driver. If possible, a driver should allocate one queue
+//! per core, to keep queue data local to a core.
+//!
+//! One `TagSet` instance can be shared between multiple `GenDisk` instances.
+//! This can be useful when implementing drivers where one piece of hardware
+//! with one set of IO resources are represented to the user as multiple disks.
+//!
+//! One significant difference between block device drivers implemented with
+//! these Rust abstractions and drivers implemented in C, is that the Rust
+//! drivers have to own a reference count on the `Request` type when the IO is
+//! in flight. This is to ensure that the C `struct request` instances backing
+//! the Rust `Request` instances are live while the Rust driver holds a
+//! reference to the `Request`. In addition, the conversion of an integer tag to
+//! a `Request` via the `TagSet` would not be sound without this bookkeeping.
+//!
+//! [`GenDisk`]: gen_disk::GenDisk
+//! [`GenDisk<T>`]: gen_disk::GenDisk
+//! [`GenDiskBuilder`]: gen_disk::GenDiskBuilder
+//! [`GenDiskBuilder::build`]: gen_disk::GenDiskBuilder::build
+//!
+//! # Example
+//!
+//! ```rust
+//! use kernel::{
+//!     alloc::flags,
+//!     block::mq::*,
+//!     new_mutex,
+//!     prelude::*,
+//!     sync::{Arc, Mutex},
+//!     types::{ARef, ForeignOwnable},
+//! };
+//!
+//! struct MyBlkDevice;
+//!
+//! #[vtable]
+//! impl Operations for MyBlkDevice {
+//!
+//!     fn queue_rq(rq: ARef<Request<Self>>, _is_last: bool) -> Result {
+//!         Request::end_ok(rq);
+//!         Ok(())
+//!     }
+//!
+//!     fn commit_rqs() {}
+//! }
+//!
+//! let tagset: Arc<TagSet<MyBlkDevice>> =
+//!     Arc::pin_init(TagSet::new(1, 256, 1), flags::GFP_KERNEL)?;
+//! let mut disk = gen_disk::GenDiskBuilder::new()
+//!     .capacity_sectors(4096)
+//!     .build(format_args!("myblk"), tagset)?;
+//!
+//! # Ok::<(), kernel::error::Error>(())
+//! ```
+
+pub mod gen_disk;
+mod operations;
+mod raw_writer;
+mod request;
+mod tag_set;
+
+pub use operations::Operations;
+pub use request::Request;
+pub use tag_set::TagSet;