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authorDave Airlie <airlied@redhat.com>2026-09-26 07:57:59 +1000
committerDave Airlie <airlied@redhat.com>2026-09-26 07:58:24 +1000
commita9ed3aa9b87ee41e8ab3ff471b1331c154767e45 (patch)
treecc62d74e0eb4905246978674461e78e2f9df2afd /drivers/block/rnull/rnull.rs
downloadlinux-stable-a9ed3aa9b87ee41e8ab3ff471b1331c154767e45.tar.gz
linux-stable-a9ed3aa9b87ee41e8ab3ff471b1331c154767e45.zip
Merge tag 'drm-misc-fixes-2026-09-24' of https://gitlab.freedesktop.org/drm/misc/kernel into drm-fixesgrafted
A number of fixes: - bridge: - samsung-dsim: fix GPIO lifetime - client: Null pointer dereference fix - imagination: error handling fix, page handling fix - nouveau: fix reference leaks, double-frees, out-of-bounds accesses, use-after-frees, don't reject config without SCDC, a number of workarounds - virtio: fix memory leak, reference leaks, null pointer dereference, add pixel blend mode, cache coherency fix Signed-off-by: Dave Airlie <airlied@redhat.com> From: Maxime Ripard <self@mripard.dev> Link: https://patch.msgid.link/arU22zzqUGDEco1y@houat
Diffstat (limited to 'drivers/block/rnull/rnull.rs')
-rw-r--r--drivers/block/rnull/rnull.rs100
1 files changed, 100 insertions, 0 deletions
diff --git a/drivers/block/rnull/rnull.rs b/drivers/block/rnull/rnull.rs
new file mode 100644
index 000000000..0ca8715fe
--- /dev/null
+++ b/drivers/block/rnull/rnull.rs
@@ -0,0 +1,100 @@
+// 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,
+ },
+ },
+ prelude::*,
+ sync::{aref::ARef, Arc},
+};
+
+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");
+ }
+}