mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2026-01-04 22:54:56 +01:00
34585dc649
rnull currently only supports direct completion. Add option for completing requests across CPU nodes via soft IRQ or IPI. Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com> Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org> Link: https://lore.kernel.org/r/20250902-rnull-up-v6-16-v7-17-b5212cc89b98@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
105 lines
2.8 KiB
Rust
105 lines
2.8 KiB
Rust
// SPDX-License-Identifier: GPL-2.0
|
|
|
|
//! This is a Rust implementation of the C null block driver.
|
|
|
|
mod configfs;
|
|
|
|
use configfs::IRQMode;
|
|
use kernel::{
|
|
block::{
|
|
self,
|
|
mq::{
|
|
self,
|
|
gen_disk::{self, GenDisk},
|
|
Operations, TagSet,
|
|
},
|
|
},
|
|
error::Result,
|
|
pr_info,
|
|
prelude::*,
|
|
sync::Arc,
|
|
types::ARef,
|
|
};
|
|
use pin_init::PinInit;
|
|
|
|
module! {
|
|
type: NullBlkModule,
|
|
name: "rnull_mod",
|
|
authors: ["Andreas Hindborg"],
|
|
description: "Rust implementation of the C null block driver",
|
|
license: "GPL v2",
|
|
}
|
|
|
|
#[pin_data]
|
|
struct NullBlkModule {
|
|
#[pin]
|
|
configfs_subsystem: kernel::configfs::Subsystem<configfs::Config>,
|
|
}
|
|
|
|
impl kernel::InPlaceModule for NullBlkModule {
|
|
fn init(_module: &'static ThisModule) -> impl PinInit<Self, Error> {
|
|
pr_info!("Rust null_blk loaded\n");
|
|
|
|
try_pin_init!(Self {
|
|
configfs_subsystem <- configfs::subsystem(),
|
|
})
|
|
}
|
|
}
|
|
|
|
struct NullBlkDevice;
|
|
|
|
impl NullBlkDevice {
|
|
fn new(
|
|
name: &CStr,
|
|
block_size: u32,
|
|
rotational: bool,
|
|
capacity_mib: u64,
|
|
irq_mode: IRQMode,
|
|
) -> Result<GenDisk<Self>> {
|
|
let tagset = Arc::pin_init(TagSet::new(1, 256, 1), GFP_KERNEL)?;
|
|
|
|
let queue_data = Box::new(QueueData { irq_mode }, GFP_KERNEL)?;
|
|
|
|
gen_disk::GenDiskBuilder::new()
|
|
.capacity_sectors(capacity_mib << (20 - block::SECTOR_SHIFT))
|
|
.logical_block_size(block_size)?
|
|
.physical_block_size(block_size)?
|
|
.rotational(rotational)
|
|
.build(fmt!("{}", name.to_str()?), tagset, queue_data)
|
|
}
|
|
}
|
|
|
|
struct QueueData {
|
|
irq_mode: IRQMode,
|
|
}
|
|
|
|
#[vtable]
|
|
impl Operations for NullBlkDevice {
|
|
type QueueData = KBox<QueueData>;
|
|
|
|
#[inline(always)]
|
|
fn queue_rq(queue_data: &QueueData, rq: ARef<mq::Request<Self>>, _is_last: bool) -> Result {
|
|
match queue_data.irq_mode {
|
|
IRQMode::None => mq::Request::end_ok(rq)
|
|
.map_err(|_e| kernel::error::code::EIO)
|
|
// We take no refcounts on the request, so we expect to be able to
|
|
// end the request. The request reference must be unique at this
|
|
// point, and so `end_ok` cannot fail.
|
|
.expect("Fatal error - expected to be able to end request"),
|
|
IRQMode::Soft => mq::Request::complete(rq),
|
|
}
|
|
Ok(())
|
|
}
|
|
|
|
fn commit_rqs(_queue_data: &QueueData) {}
|
|
|
|
fn complete(rq: ARef<mq::Request<Self>>) {
|
|
mq::Request::end_ok(rq)
|
|
.map_err(|_e| kernel::error::code::EIO)
|
|
// We take no refcounts on the request, so we expect to be able to
|
|
// end the request. The request reference must be unique at this
|
|
// point, and so `end_ok` cannot fail.
|
|
.expect("Fatal error - expected to be able to end request");
|
|
}
|
|
}
|