[GIT PULL PATCH 0/9] Rust changes for v7.4-rc1

[GIT PULL PATCH 0/9] Rust changes for v7.4-rc1

[Andreas Hindborg]

Hi Jens,

I have a number of Rust block layer patches I would ask you to pick for
v7.4. I have collected them into a patch series as well as a pull request
so you can use whatever is easier.

The changes cover

 - Style and formatting changes.
 - Documentation fixes.
 - Fixes for missing trait bounds that can cause API unsoundness.
 - A change to set the owner of the file operations vtable in `GenDisk`.
 - Two bug fixes for the rnull driver.

The following changes since commit df2908090cda368b01ff43709f51890076c56157:

  Linux 7.3-rc2 (2026-09-06 15:07:20 -0700)

are available in the Git repository at:

  https://github.com/rust-for-linux/linux.git tags/rust-block-for-v7.4-rc1

for you to fetch changes up to b6cfe408d16ecb68a8b10b0d738669aeaecbde6f:

  rust: block: require `Sync` for `Operations::QueueData` (2026-09-29 11:23:27 +0200)

Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
---
Alvin Sun (4):
      rust: block: mq: use vertical import style
      rust: block: mq: remove redundant imports and format
      rust: block: rnull: use vertical import style
      rust: block: gen_disk: set fops.owner from driver module pointer

Andreas Hindborg (2):
      rust: block: fix `Send` bound for `GenDisk`
      rust: block: require `Sync` for `Operations::QueueData`

Malte Wechter (1):
      rnull: configfs: add power to configfs features

Qingxiao Xu (1):
      rnull: fix geometry store check-then-act across lock scopes

Sophon Z (1):
      rust: block: Fix GenDiskBuilder block size documentation

 drivers/block/rnull/configfs.rs    | 44 +++++++++++++++--------
 drivers/block/rnull/rnull.rs       | 15 +++++---
 rust/kernel/block/mq/gen_disk.rs   | 72 ++++++++++++++++++++------------------
 rust/kernel/block/mq/operations.rs | 16 ++++++---
 rust/kernel/block/mq/request.rs    | 16 ++++++---
 rust/kernel/block/mq/tag_set.rs    | 28 +++++++--------
 6 files changed, 115 insertions(+), 76 deletions(-)
---
base-commit: df2908090cda368b01ff43709f51890076c56157
change-id: 20260929-rust-block-for-v7-4-rc1-b4-6fac377c366c

Best regards,
--  
Andreas Hindborg <a.hindborg@kernel.org>

[PATCH GIT PULL 1/9] rust: block: mq: use vertical import style

[Andreas Hindborg]

From: Alvin Sun <alvin.sun@linux.dev>

Convert `use` imports to vertical layout for better readability and
maintainability.

Reviewed-by: Onur Özkan <work@onurozkan.dev>
Signed-off-by: Alvin Sun <alvin.sun@linux.dev>
Link: https://msgid.link/20260521-miscdev-use-format-v3-4-56240ca70d0c@linux.dev
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
---
 rust/kernel/block/mq/gen_disk.rs   | 21 +++++++++++++++++----
 rust/kernel/block/mq/operations.rs | 17 +++++++++++++----
 rust/kernel/block/mq/request.rs    | 14 ++++++++++----
 rust/kernel/block/mq/tag_set.rs    | 24 +++++++++++++++++++-----
 4 files changed, 59 insertions(+), 17 deletions(-)

diff --git a/rust/kernel/block/mq/gen_disk.rs b/rust/kernel/block/mq/gen_disk.rs
index fc97dd873974..31cc7a77c2b5 100644
--- a/rust/kernel/block/mq/gen_disk.rs
+++ b/rust/kernel/block/mq/gen_disk.rs
@@ -7,14 +7,27 @@
 
 use crate::{
     bindings,
-    block::mq::{Operations, TagSet},
-    error::{self, from_err_ptr, Result},
-    fmt::{self, Write},
+    block::mq::{
+        Operations,
+        TagSet, //
+    },
+    error::{
+        self,
+        from_err_ptr,
+        Result, //
+    },
+    fmt::{
+        self,
+        Write, //
+    },
     prelude::*,
     static_lock_class,
     str::NullTerminatedFormatter,
     sync::Arc,
-    types::{ForeignOwnable, ScopeGuard},
+    types::{
+        ForeignOwnable,
+        ScopeGuard, //
+    }, //
 };
 
 /// A builder for [`GenDisk`].
diff --git a/rust/kernel/block/mq/operations.rs b/rust/kernel/block/mq/operations.rs
index 861903e18fbf..64bcb31666c0 100644
--- a/rust/kernel/block/mq/operations.rs
+++ b/rust/kernel/block/mq/operations.rs
@@ -6,11 +6,20 @@
 
 use crate::{
     bindings,
-    block::mq::{request::RequestDataWrapper, Request},
-    error::{from_result, Result},
+    block::mq::{
+        request::RequestDataWrapper,
+        Request, //
+    },
+    error::{
+        from_result,
+        Result, //
+    },
     prelude::*,
-    sync::{aref::ARef, Refcount},
-    types::ForeignOwnable,
+    sync::{
+        aref::ARef,
+        Refcount, //
+    },
+    types::ForeignOwnable, //
 };
 use core::marker::PhantomData;
 
diff --git a/rust/kernel/block/mq/request.rs b/rust/kernel/block/mq/request.rs
index ce3e30c81cb5..66254d02bba6 100644
--- a/rust/kernel/block/mq/request.rs
+++ b/rust/kernel/block/mq/request.rs
@@ -9,13 +9,19 @@
     block::mq::Operations,
     error::Result,
     sync::{
-        aref::{ARef, AlwaysRefCounted},
+        aref::{
+            ARef,
+            AlwaysRefCounted, //
+        },
         atomic::Relaxed,
-        Refcount,
+        Refcount, //
     },
-    types::Opaque,
+    types::Opaque, //
+};
+use core::{
+    marker::PhantomData,
+    ptr::NonNull, //
 };
-use core::{marker::PhantomData, ptr::NonNull};
 
 /// A wrapper around a blk-mq [`struct request`]. This represents an IO request.
 ///
diff --git a/rust/kernel/block/mq/tag_set.rs b/rust/kernel/block/mq/tag_set.rs
index dae9df408a86..c1fd3e047af5 100644
--- a/rust/kernel/block/mq/tag_set.rs
+++ b/rust/kernel/block/mq/tag_set.rs
@@ -8,13 +8,27 @@
 
 use crate::{
     bindings,
-    block::mq::{operations::OperationsVTable, request::RequestDataWrapper, Operations},
-    error::{self, Result},
+    block::mq::{
+        operations::OperationsVTable,
+        request::RequestDataWrapper,
+        Operations, //
+    },
+    error::{
+        self,
+        Result, //
+    },
     prelude::try_pin_init,
-    types::Opaque,
+    types::Opaque, //
+};
+use core::{
+    convert::TryInto,
+    marker::PhantomData, //
+};
+use pin_init::{
+    pin_data,
+    pinned_drop,
+    PinInit, //
 };
-use core::{convert::TryInto, marker::PhantomData};
-use pin_init::{pin_data, pinned_drop, PinInit};
 
 /// A wrapper for the C `struct blk_mq_tag_set`.
 ///

-- 
2.54.0

[PATCH GIT PULL 2/9] rust: block: mq: remove redundant imports and format

[Andreas Hindborg]

From: Alvin Sun <alvin.sun@linux.dev>

Drop `Result`, `Pin`, `pin_data`, `pinned_drop`, `PinInit`, and
`try_pin_init` imports already provided by `kernel::prelude`.

Simplify `error` imports and flatten parameters formatting.

Reviewed-by: Onur Özkan <work@onurozkan.dev>
Signed-off-by: Alvin Sun <alvin.sun@linux.dev>
Acked-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://msgid.link/20260521-miscdev-use-format-v3-5-56240ca70d0c@linux.dev
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
---
 rust/kernel/block/mq/gen_disk.rs   |  7 +++----
 rust/kernel/block/mq/operations.rs |  5 +----
 rust/kernel/block/mq/request.rs    |  2 +-
 rust/kernel/block/mq/tag_set.rs    | 22 ++++------------------
 4 files changed, 9 insertions(+), 27 deletions(-)

diff --git a/rust/kernel/block/mq/gen_disk.rs b/rust/kernel/block/mq/gen_disk.rs
index 31cc7a77c2b5..8ec38a7b9815 100644
--- a/rust/kernel/block/mq/gen_disk.rs
+++ b/rust/kernel/block/mq/gen_disk.rs
@@ -12,9 +12,8 @@
         TagSet, //
     },
     error::{
-        self,
         from_err_ptr,
-        Result, //
+        to_result, //
     },
     fmt::{
         self,
@@ -67,7 +66,7 @@ pub fn rotational(mut self, rotational: bool) -> Self {
     /// and that it is a power of two.
     pub fn validate_block_size(size: u32) -> Result {
         if !(512..=bindings::PAGE_SIZE as u32).contains(&size) || !size.is_power_of_two() {
-            Err(error::code::EINVAL)
+            Err(EINVAL)
         } else {
             Ok(())
         }
@@ -190,7 +189,7 @@ pub fn build<T: Operations>(
         // operation, so we will not race.
         unsafe { bindings::set_capacity(gendisk, self.capacity_sectors) };
 
-        crate::error::to_result(
+        to_result(
             // SAFETY: `gendisk` points to a valid and initialized instance of
             // `struct gendisk`.
             unsafe {
diff --git a/rust/kernel/block/mq/operations.rs b/rust/kernel/block/mq/operations.rs
index 64bcb31666c0..b9ab0e6102a4 100644
--- a/rust/kernel/block/mq/operations.rs
+++ b/rust/kernel/block/mq/operations.rs
@@ -10,10 +10,7 @@
         request::RequestDataWrapper,
         Request, //
     },
-    error::{
-        from_result,
-        Result, //
-    },
+    error::from_result,
     prelude::*,
     sync::{
         aref::ARef,
diff --git a/rust/kernel/block/mq/request.rs b/rust/kernel/block/mq/request.rs
index 66254d02bba6..6115f9aec228 100644
--- a/rust/kernel/block/mq/request.rs
+++ b/rust/kernel/block/mq/request.rs
@@ -7,7 +7,7 @@
 use crate::{
     bindings,
     block::mq::Operations,
-    error::Result,
+    prelude::*,
     sync::{
         aref::{
             ARef,
diff --git a/rust/kernel/block/mq/tag_set.rs b/rust/kernel/block/mq/tag_set.rs
index c1fd3e047af5..df3f90bfbb81 100644
--- a/rust/kernel/block/mq/tag_set.rs
+++ b/rust/kernel/block/mq/tag_set.rs
@@ -4,8 +4,6 @@
 //!
 //! C header: [`include/linux/blk-mq.h`](srctree/include/linux/blk-mq.h)
 
-use core::pin::Pin;
-
 use crate::{
     bindings,
     block::mq::{
@@ -13,22 +11,14 @@
         request::RequestDataWrapper,
         Operations, //
     },
-    error::{
-        self,
-        Result, //
-    },
-    prelude::try_pin_init,
+    error::to_result,
+    prelude::*,
     types::Opaque, //
 };
 use core::{
     convert::TryInto,
     marker::PhantomData, //
 };
-use pin_init::{
-    pin_data,
-    pinned_drop,
-    PinInit, //
-};
 
 /// A wrapper for the C `struct blk_mq_tag_set`.
 ///
@@ -47,11 +37,7 @@ pub struct TagSet<T: Operations> {
 
 impl<T: Operations> TagSet<T> {
     /// Try to create a new tag set
-    pub fn new(
-        nr_hw_queues: u32,
-        num_tags: u32,
-        num_maps: u32,
-    ) -> impl PinInit<Self, error::Error> {
+    pub fn new(nr_hw_queues: u32, num_tags: u32, num_maps: u32) -> impl PinInit<Self, Error> {
         let tag_set: bindings::blk_mq_tag_set = pin_init::zeroed();
         let tag_set: Result<_> = core::mem::size_of::<RequestDataWrapper>()
             .try_into()
@@ -77,7 +63,7 @@ pub fn new(
                 // SAFETY: we do not move out of `tag_set`.
                 let tag_set: &mut Opaque<_> = unsafe { Pin::get_unchecked_mut(tag_set) };
                 // SAFETY: `tag_set` is a reference to an initialized `blk_mq_tag_set`.
-                error::to_result( unsafe { bindings::blk_mq_alloc_tag_set(tag_set.get())})
+                to_result( unsafe { bindings::blk_mq_alloc_tag_set(tag_set.get())})
             }),
             _p: PhantomData,
         })

-- 
2.54.0

[PATCH GIT PULL 3/9] rust: block: rnull: use vertical import style

[Andreas Hindborg]

From: Alvin Sun <alvin.sun@linux.dev>

Convert `use` imports to vertical layout for better readability and
maintainability.

Signed-off-by: Alvin Sun <alvin.sun@linux.dev>
Link: https://msgid.link/20260521-miscdev-use-format-v3-6-56240ca70d0c@linux.dev
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
---
 drivers/block/rnull/configfs.rs | 22 +++++++++++++++++-----
 drivers/block/rnull/rnull.rs    | 15 +++++++++++----
 2 files changed, 28 insertions(+), 9 deletions(-)

diff --git a/drivers/block/rnull/configfs.rs b/drivers/block/rnull/configfs.rs
index 32c10c3f4d0f..9b28be215093 100644
--- a/drivers/block/rnull/configfs.rs
+++ b/drivers/block/rnull/configfs.rs
@@ -2,15 +2,27 @@
 
 use super::NullBlkDevice;
 use kernel::{
-    block::mq::gen_disk::{GenDisk, GenDiskBuilder},
-    configfs::{self, AttributeOperations},
+    block::mq::gen_disk::{
+        GenDisk,
+        GenDiskBuilder, //
+    },
+    configfs::{
+        self,
+        AttributeOperations, //
+    },
     configfs_attrs,
-    fmt::{self, Write as _},
+    fmt::{
+        self,
+        Write as _, //
+    },
     new_mutex,
     page::PAGE_SIZE,
     prelude::*,
-    str::{kstrtobool_bytes, CString},
-    sync::Mutex,
+    str::{
+        kstrtobool_bytes,
+        CString, //
+    },
+    sync::Mutex, //
 };
 
 pub(crate) fn subsystem() -> impl PinInit<kernel::configfs::Subsystem<Config>, Error> {
diff --git a/drivers/block/rnull/rnull.rs b/drivers/block/rnull/rnull.rs
index 0ca8715febe8..13048cea8bb0 100644
--- a/drivers/block/rnull/rnull.rs
+++ b/drivers/block/rnull/rnull.rs
@@ -10,12 +10,19 @@
         self,
         mq::{
             self,
-            gen_disk::{self, GenDisk},
-            Operations, TagSet,
-        },
+            gen_disk::{
+                self,
+                GenDisk, //
+            },
+            Operations,
+            TagSet, //
+        }, //
     },
     prelude::*,
-    sync::{aref::ARef, Arc},
+    sync::{
+        aref::ARef,
+        Arc, //
+    }, //
 };
 
 module! {

-- 
2.54.0

[PATCH GIT PULL 4/9] rust: block: fix `Send` bound for `GenDisk`

[Andreas Hindborg]

The `Send` implementation for `GenDisk<T>` was conditioned on `T: Send`.
This constrains the wrong type. `T` is the `Operations` implementation,
which is typically a zero-sized marker type that carries no data, so `T:
Send` says nothing about whether the data a `GenDisk` actually owns can be
moved to another thread.

A `GenDisk<T>` owns the queue data `T::QueueData` (stored as the
`gendisk`'s `queuedata` and dropped when the `GenDisk` is dropped) and an
`Arc<TagSet<T>>`. These are the values transferred when a `GenDisk` is sent
across a thread boundary, so the `Send` bound must constrain exactly them.
Bound `T::QueueData: Send` and `Arc<TagSet<T>>: Send` instead.

Fixes: 3253aba3408a ("rust: block: introduce `kernel::block::mq` module")
Cc: stable@vger.kernel.org
Reported-by: Priya Bala Govindasamy <pgovind2@uci.edu>, Dylan Zueck <dzueck@uci.edu>, Yuan Tan <ytan089@ucr.edu>
Closes: https://lore.kernel.org/all/cover.1780633578.git.ytan089@ucr.edu
Signed-off-by: Yuan Tan <ytan089@ucr.edu>
Link: https://msgid.link/20260709100100.604252-1-yuantan098@gmail.com
[ Andreas: Fix tags to make checkpatch happy. Change summary line. ]
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
---
 rust/kernel/block/mq/gen_disk.rs | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/rust/kernel/block/mq/gen_disk.rs b/rust/kernel/block/mq/gen_disk.rs
index 8ec38a7b9815..080dedb5d5d9 100644
--- a/rust/kernel/block/mq/gen_disk.rs
+++ b/rust/kernel/block/mq/gen_disk.rs
@@ -224,8 +224,14 @@ pub struct GenDisk<T: Operations> {
 }
 
 // SAFETY: `GenDisk` is an owned pointer to a `struct gendisk` and an `Arc` to a
-// `TagSet` It is safe to send this to other threads as long as T is Send.
-unsafe impl<T: Operations + Send> Send for GenDisk<T> {}
+// `TagSet`. It is safe to send this to other threads as long as these two are `Send`.
+unsafe impl<T> Send for GenDisk<T>
+where
+    T: Operations,
+    T::QueueData: Send,
+    Arc<TagSet<T>>: Send,
+{
+}
 
 impl<T: Operations> Drop for GenDisk<T> {
     fn drop(&mut self) {

-- 
2.54.0

[PATCH GIT PULL 5/9] rust: block: gen_disk: set fops.owner from driver module pointer

[Andreas Hindborg]

From: Alvin Sun <alvin.sun@linux.dev>

Set `fops.owner` from the driver module pointer via
`this_module::<T::OwnerModule>().as_ptr()` instead of defaulting to
null, so the module cannot be unloaded while a block device is still
in use.

Signed-off-by: Alvin Sun <alvin.sun@linux.dev>
Link: https://msgid.link/20260811-fix-gendisk-owner-v1-1-c0fe4a449ecb@linux.dev
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
---
 rust/kernel/block/mq/gen_disk.rs | 34 ++++++++++------------------------
 1 file changed, 10 insertions(+), 24 deletions(-)

diff --git a/rust/kernel/block/mq/gen_disk.rs b/rust/kernel/block/mq/gen_disk.rs
index 080dedb5d5d9..90d364ab3bf2 100644
--- a/rust/kernel/block/mq/gen_disk.rs
+++ b/rust/kernel/block/mq/gen_disk.rs
@@ -137,30 +137,9 @@ pub fn build<T: Operations>(
             )
         })?;
 
-        const TABLE: bindings::block_device_operations = bindings::block_device_operations {
-            submit_bio: None,
-            open: None,
-            release: None,
-            ioctl: None,
-            compat_ioctl: None,
-            check_events: None,
-            unlock_native_capacity: None,
-            getgeo: None,
-            set_read_only: None,
-            swap_slot_free_notify: None,
-            report_zones: None,
-            devnode: None,
-            alternative_gpt_sector: None,
-            get_unique_id: None,
-            // TODO: Set to `THIS_MODULE`.
-            owner: core::ptr::null_mut(),
-            pr_ops: core::ptr::null_mut(),
-            free_disk: None,
-            poll_bio: None,
-        };
-
-        // SAFETY: `gendisk` is a valid pointer as we initialized it above
-        unsafe { (*gendisk).fops = &TABLE };
+        // SAFETY: `gendisk` is a valid pointer. We have exclusive access,
+        // since the disk is not added to the VFS yet.
+        unsafe { (*gendisk).fops = &GenDisk::<T>::VTABLE };
 
         let cleanup_failure = ScopeGuard::new_with_data((gendisk, data), |(gendisk, data)| {
             // SAFETY: `gendisk` came from `__blk_mq_alloc_disk()` above and
@@ -223,6 +202,13 @@ pub struct GenDisk<T: Operations> {
     gendisk: *mut bindings::gendisk,
 }
 
+impl<T: Operations> GenDisk<T> {
+    const VTABLE: bindings::block_device_operations = bindings::block_device_operations {
+        owner: crate::module::this_module::<T::OwnerModule>().as_ptr(),
+        ..pin_init::zeroed()
+    };
+}
+
 // SAFETY: `GenDisk` is an owned pointer to a `struct gendisk` and an `Arc` to a
 // `TagSet`. It is safe to send this to other threads as long as these two are `Send`.
 unsafe impl<T> Send for GenDisk<T>

-- 
2.54.0

[PATCH GIT PULL 6/9] rust: block: Fix GenDiskBuilder block size documentation

[Andreas Hindborg]

From: Sophon Z <aiqubits@hotmail.com>

GenDiskBuilder::validate_block_size() accepts powers of two from 512
through PAGE_SIZE, but the documentation for logical_block_size() and
physical_block_size() states that the maximum is 4096.

Use PAGE_SIZE for both documented upper bounds so that the documentation
matches validation on architectures with larger page sizes.

Signed-off-by: Sophon Z <aiqubits@hotmail.com>
Acked-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://msgid.link/20260831-fix-gendisk-block-size-docs-v1-1-900546005799@hotmail.com
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
---
 rust/kernel/block/mq/gen_disk.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/rust/kernel/block/mq/gen_disk.rs b/rust/kernel/block/mq/gen_disk.rs
index 90d364ab3bf2..0fe640f3aec6 100644
--- a/rust/kernel/block/mq/gen_disk.rs
+++ b/rust/kernel/block/mq/gen_disk.rs
@@ -75,7 +75,7 @@ pub fn validate_block_size(size: u32) -> Result {
     /// Set the logical block size of the device to be built.
     ///
     /// This method will check that block size is a power of two and between 512
-    /// and 4096. If not, an error is returned and the block size is not set.
+    /// and `PAGE_SIZE`. If not, an error is returned and the block size is not set.
     ///
     /// This is the smallest unit the storage device can address. It is
     /// typically 4096 bytes.
@@ -88,7 +88,7 @@ pub fn logical_block_size(mut self, block_size: u32) -> Result<Self> {
     /// Set the physical block size of the device to be built.
     ///
     /// This method will check that block size is a power of two and between 512
-    /// and 4096. If not, an error is returned and the block size is not set.
+    /// and `PAGE_SIZE`. If not, an error is returned and the block size is not set.
     ///
     /// This is the smallest unit a physical storage device can write
     /// atomically. It is usually the same as the logical block size but may be

-- 
2.54.0

[PATCH GIT PULL 7/9] rnull: fix geometry store check-then-act across lock scopes

[Andreas Hindborg]

From: Qingxiao Xu <qingxiao@tamu.edu>

The blocksize/rotational/capacity/irqmode stores check powered under one
Mutex acquisition, drop the guard, then update under a second acquisition.
A concurrent power-on can create the live disk from stale geometry in
between, leaving powered==true with config != live disk.

Hold one guard for the powered check and the field update.

Signed-off-by: Qingxiao Xu <qingxiao@tamu.edu>
Link: https://msgid.link/20260908200845.405112-1-qingxiao@tamu.edu
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
---
 drivers/block/rnull/configfs.rs | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/drivers/block/rnull/configfs.rs b/drivers/block/rnull/configfs.rs
index 9b28be215093..24b02256b4cd 100644
--- a/drivers/block/rnull/configfs.rs
+++ b/drivers/block/rnull/configfs.rs
@@ -186,7 +186,8 @@ impl configfs::AttributeOperations<1> for DeviceConfig {
     }
 
     fn store(this: &DeviceConfig, page: &[u8]) -> Result {
-        if this.data.lock().powered {
+        let mut guard = this.data.lock();
+        if guard.powered {
             return Err(EBUSY);
         }
 
@@ -194,7 +195,7 @@ fn store(this: &DeviceConfig, page: &[u8]) -> Result {
         let value = text.parse::<u32>().map_err(|_| EINVAL)?;
 
         GenDiskBuilder::validate_block_size(value)?;
-        this.data.lock().block_size = value;
+        guard.block_size = value;
         Ok(())
     }
 }
@@ -216,11 +217,12 @@ impl configfs::AttributeOperations<2> for DeviceConfig {
     }
 
     fn store(this: &DeviceConfig, page: &[u8]) -> Result {
-        if this.data.lock().powered {
+        let mut guard = this.data.lock();
+        if guard.powered {
             return Err(EBUSY);
         }
 
-        this.data.lock().rotational = kstrtobool_bytes(page)?;
+        guard.rotational = kstrtobool_bytes(page)?;
 
         Ok(())
     }
@@ -237,14 +239,15 @@ impl configfs::AttributeOperations<3> for DeviceConfig {
     }
 
     fn store(this: &DeviceConfig, page: &[u8]) -> Result {
-        if this.data.lock().powered {
+        let mut guard = this.data.lock();
+        if guard.powered {
             return Err(EBUSY);
         }
 
         let text = core::str::from_utf8(page)?.trim();
         let value = text.parse::<u64>().map_err(|_| EINVAL)?;
 
-        this.data.lock().capacity_mib = value;
+        guard.capacity_mib = value;
         Ok(())
     }
 }
@@ -260,14 +263,15 @@ impl configfs::AttributeOperations<4> for DeviceConfig {
     }
 
     fn store(this: &DeviceConfig, page: &[u8]) -> Result {
-        if this.data.lock().powered {
+        let mut guard = this.data.lock();
+        if guard.powered {
             return Err(EBUSY);
         }
 
         let text = core::str::from_utf8(page)?.trim();
         let value = text.parse::<u8>().map_err(|_| EINVAL)?;
 
-        this.data.lock().irq_mode = IRQMode::try_from(value)?;
+        guard.irq_mode = IRQMode::try_from(value)?;
         Ok(())
     }
 }

-- 
2.54.0

[PATCH GIT PULL 8/9] rnull: configfs: add power to configfs features

[Andreas Hindborg]

From: Malte Wechter <maltewechter@gmail.com>

features displayed by configfs for rnull was inconsistent with the
actual features available. This correctly exposes `power` as a feature,
which is also consistent with the C null_blk driver.

Fixes: d969d504bc13 ("rnull: enable configuration via `configfs`")

Signed-off-by: Malte Wechter <maltewechter@gmail.com>
Link: https://msgid.link/20260924-upstream-v7-3-rc3-v2-1-ca56ae7a73e9@gmail.com
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
---
 drivers/block/rnull/configfs.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/block/rnull/configfs.rs b/drivers/block/rnull/configfs.rs
index 24b02256b4cd..34ef96fa125f 100644
--- a/drivers/block/rnull/configfs.rs
+++ b/drivers/block/rnull/configfs.rs
@@ -47,7 +47,7 @@ impl AttributeOperations<0> for Config {
 
     fn show(_this: &Config, page: &mut [u8; PAGE_SIZE]) -> Result<usize> {
         let mut writer = kernel::str::Formatter::new(page);
-        writer.write_str("blocksize,size,rotational,irqmode\n")?;
+        writer.write_str("blocksize,size,rotational,irqmode,power\n")?;
         Ok(writer.bytes_written())
     }
 }

-- 
2.54.0

[PATCH GIT PULL 9/9] rust: block: require `Sync` for `Operations::QueueData`

[Andreas Hindborg]

The queue data installed in a `GenDisk` is stored in the request queue and
handed back to the driver as a shared borrow through the `queue_rq` and
`commit_rqs` callbacks. Both callbacks obtain that borrow via
`ForeignOwnable::borrow` and may execute concurrently on several CPUs,
since the block layer runs one hardware queue per CPU. That means a shared
reference to the same queue data can be live on multiple threads at once,
which is only sound when the referent is `Sync`.

The initial `GenDisk` private data support omitted this bound, so a
driver could install a non-`Sync` type as queue data and then access
it concurrently from multiple CPUs without synchronization. Add a
`Sync` bound to the `QueueData` associated type to rule that out.

Fixes: 90d952fac8ac ("rust: block: add `GenDisk` private data support")
Cc: stable@vger.kernel.org
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://msgid.link/20260608-queue-data-sync-v1-1-0efff051aaf3@kernel.org
Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
---
 rust/kernel/block/mq/operations.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/rust/kernel/block/mq/operations.rs b/rust/kernel/block/mq/operations.rs
index b9ab0e6102a4..08111d8368eb 100644
--- a/rust/kernel/block/mq/operations.rs
+++ b/rust/kernel/block/mq/operations.rs
@@ -36,7 +36,7 @@
 pub trait Operations: Sized {
     /// Data associated with the `struct request_queue` that is allocated for
     /// the `GenDisk` associated with this `Operations` implementation.
-    type QueueData: ForeignOwnable;
+    type QueueData: ForeignOwnable + Sync;
 
     /// Called by the kernel to queue a request with the driver. If `is_last` is
     /// `false`, the driver is allowed to defer committing the request.

-- 
2.54.0

Re: [GIT PULL PATCH 0/9] Rust changes for v7.4-rc1

[Jens Axboe]

On Tue, 29 Sep 2026 11:33:58 +0200, Andreas Hindborg wrote:
> I have a number of Rust block layer patches I would ask you to pick for
> v7.4. I have collected them into a patch series as well as a pull request
> so you can use whatever is easier.
> 
> The changes cover
> 
>  - Style and formatting changes.
>  - Documentation fixes.
>  - Fixes for missing trait bounds that can cause API unsoundness.
>  - A change to set the owner of the file operations vtable in `GenDisk`.
>  - Two bug fixes for the rnull driver.
> 
> [...]

Applied, thanks!

[1/9] rust: block: mq: use vertical import style
      commit: 020185c5f4a5590267b825dffda05eb5d45dfa5f
[2/9] rust: block: mq: remove redundant imports and format
      commit: 06e75dbe894f260651627c35e0f36536c4894536
[3/9] rust: block: rnull: use vertical import style
      commit: a463f71c492336f9650bae7d7166b66ee87461e9
[4/9] rust: block: fix `Send` bound for `GenDisk`
      commit: e502b667ee70a7fa2a578e7722672ecd4fe0eb81
[5/9] rust: block: gen_disk: set fops.owner from driver module pointer
      commit: 67a11f2e076016f054dc4a4a637d9b37530b7908
[6/9] rust: block: Fix GenDiskBuilder block size documentation
      commit: c595572d0e49c79fcefe8db8e3e4f4e6e1fab734
[7/9] rnull: fix geometry store check-then-act across lock scopes
      commit: 7ac697d4a08f01e7aefdeb1f3e1d6f71b2cdac0d
[8/9] rnull: configfs: add power to configfs features
      commit: 0cd698e89375d0dfc257f9ae978420aa7fe5359d
[9/9] rust: block: require `Sync` for `Operations::QueueData`
      commit: 67b7a2728e4873e64405c5564fe50f7123012b71

Best regards,
-- 
Jens Axboe

Re: [GIT PULL PATCH 0/9] Rust changes for v7.4-rc1

[Thorsten Leemhuis]

On 9/29/26 13:47, Jens Axboe wrote:
> On Tue, 29 Sep 2026 11:33:58 +0200, Andreas Hindborg wrote:
>> I have a number of Rust block layer patches I would ask you to pick for
>> v7.4. I have collected them into a patch series as well as a pull request
>> so you can use whatever is easier.
>>
>> The changes cover
>>
>>  - Style and formatting changes.
>>  - Documentation fixes.
>>  - Fixes for missing trait bounds that can cause API unsoundness.
>>  - A change to set the owner of the file operations vtable in `GenDisk`.
>>  - Two bug fixes for the rnull driver.
>>
>> [...]
> 
> Applied, thanks!
>  [...]

This series showed up in next today and broke the build for me on
various Fedora releases for aarch64 and x86_64; reverting this series
fixed that from a quick build test limited to drivers/block/rnull/

The full error msg is quote long, find the top of it below. Full log:
https://download.copr.fedorainfracloud.org/results/@kernel-vanilla/next/fedora-rawhide-aarch64/11055137-next-next-all/builder-live.log.gz

Ciao, Thorsten

"""
> error[E0277]: `UnsafeCell<MaybeUninit<blk_mq_tag_set>>` cannot be shared between threads safely
>    --> drivers/block/rnull/configfs.rs:57:18
>     |
>  57 |     type Child = DeviceConfig;
>     |                  ^^^^^^^^^^^^ `UnsafeCell<MaybeUninit<blk_mq_tag_set>>` cannot be shared between threads safely
>     |
>     = help: within `TagSet<NullBlkDevice>`, the trait `Sync` is not implemented for `UnsafeCell<MaybeUninit<blk_mq_tag_set>>`
> note: required because it appears within the type `Opaque<blk_mq_tag_set>`
>    --> rust/kernel/types.rs:332:12
>     |
> 332 | pub struct Opaque<T> {
>     |            ^^^^^^
> note: required because it appears within the type `TagSet<NullBlkDevice>`
>    --> rust/kernel/block/mq/tag_set.rs:32:12
>     |
>  32 | pub struct TagSet<T: Operations> {
>     |            ^^^^^^
>     = note: required for `Arc<TagSet<NullBlkDevice>>` to implement `Send`
>     = note: 1 redundant requirement hidden
>     = note: required for `GenDisk<NullBlkDevice>` to implement `Send`
> note: required because it appears within the type `Option<GenDisk<NullBlkDevice>>`
>    --> /usr/lib/rustlib/src/rust/library/core/src/option.rs:598:10
>     |
> 598 | pub enum Option<T> {
>     |          ^^^^^^
> note: required because it appears within the type `DeviceConfigInner`
>    --> drivers/block/rnull/configfs.rs:130:8
>     |
> 130 | struct DeviceConfigInner {
>     |        ^^^^^^^^^^^^^^^^^
>     = note: required for `Lock<DeviceConfigInner, MutexBackend>` to implement `Send`
> note: required because it appears within the type `DeviceConfig`
>    --> drivers/block/rnull/configfs.rs:124:19
>     |
> 124 | pub(crate) struct DeviceConfig {
>     |                   ^^^^^^^^^^^^
> note: required by a bound in `kernel::configfs::GroupOperations::Child`
>    --> rust/kernel/configfs.rs:518:27
>     |
> 518 |     type Child: 'static + Send;
>     |                           ^^^^ required by this bound in `GroupOperations::Child`
> 
> error[E0277]: `*const blk_mq_ops` cannot be sent between threads safely
>       --> drivers/block/rnull/configfs.rs:57:18
>        |
>     57 |     type Child = DeviceConfig;
>        |                  ^^^^^^^^^^^^ `*const blk_mq_ops` cannot be sent between threads safely
>        |
>        = help: within `TagSet<NullBlkDevice>`, the trait `Send` is not implemented for `*const blk_mq_ops`
> note: required because it appears within the type `blk_mq_tag_set`
>       --> /builddir/build/BUILD/kernel-7.3.0-build/kernel-next-20260930/linux-7.3.0-0.0.next.20260930.545.vanilla.fc46.aarch64/rust/bindings/bindings_generated.rs:105198:12
>        |
> 105198 | pub struct blk_mq_tag_set {
>        |            ^^^^^^^^^^^^^^
> note: required because it appears within the type `MaybeDangling<blk_mq_tag_set>`
>       --> /usr/lib/rustlib/src/rust/library/core/src/mem/maybe_dangling.rs:73:12
>        |
>     73 | pub struct MaybeDangling<P: ?Sized>(P);
> [...]"""

Re: [GIT PULL PATCH 0/9] Rust changes for v7.4-rc1

[Miguel Ojeda]

On Wed, Sep 30, 2026 at 5:07 PM Thorsten Leemhuis <linux@leemhuis.info> wrote:
>
> This series showed up in next today and broke the build for me on
> various Fedora releases for aarch64 and x86_64; reverting this series
> fixed that from a quick build test limited to drivers/block/rnull/
>
> The full error msg is quote long, find the top of it below. Full log:
> https://download.copr.fedorainfracloud.org/results/@kernel-vanilla/next/fedora-rawhide-aarch64/11055137-next-next-all/builder-live.log.gz

Confirmed, I see it e.g. in my arm32 build.

Cheers,
Miguel

Re: [GIT PULL PATCH 0/9] Rust changes for v7.4-rc1

[Gary Guo]

On Wed Sep 30, 2026 at 4:06 PM BST, Thorsten Leemhuis wrote:
> On 9/29/26 13:47, Jens Axboe wrote:
>> On Tue, 29 Sep 2026 11:33:58 +0200, Andreas Hindborg wrote:
>>> I have a number of Rust block layer patches I would ask you to pick for
>>> v7.4. I have collected them into a patch series as well as a pull request
>>> so you can use whatever is easier.
>>>
>>> The changes cover
>>>
>>>  - Style and formatting changes.
>>>  - Documentation fixes.
>>>  - Fixes for missing trait bounds that can cause API unsoundness.
>>>  - A change to set the owner of the file operations vtable in `GenDisk`.
>>>  - Two bug fixes for the rnull driver.
>>>
>>> [...]
>> 
>> Applied, thanks!
>>  [...]
>
> This series showed up in next today and broke the build for me on
> various Fedora releases for aarch64 and x86_64; reverting this series
> fixed that from a quick build test limited to drivers/block/rnull/
>
> The full error msg is quote long, find the top of it below. Full log:
> https://download.copr.fedorainfracloud.org/results/@kernel-vanilla/next/fedora-rawhide-aarch64/11055137-next-next-all/builder-live.log.gz

The `Child: Send` bound is introduced in configfs:
https://lore.kernel.org/all/tencent_05937A22D2DA2BAE808EF19E491AA109BC09@qq.com/.
So this is more or less a semantic conflict.

However, the fundamental issue is that TagSet never implements Send/Sync, which
means that "rust: block: fix `Send` bound for `GenDisk`" will unconditionally
strip away the Send implementation, which is problematic.

Something like this should fix the issue:

    unsafe impl<T: Operations<QueueData: Send>> Send for TagSet<T> {}
    unsafe impl<T: Operations<QueueData: Send>> Sync for TagSet<T> {}

That said, I am not sure why the GenDisk need to carry `Arc<TagSet<T>>: Send`
bound in the first place. Removing it should also fix the issue.

Also, the `QueueData: Send` bound should be part of the `Operations` trait and
not carried around everywhere.

Best,
Gary

Re: [GIT PULL PATCH 0/9] Rust changes for v7.4-rc1

[Andreas Hindborg]

"Gary Guo" <gary@garyguo.net> writes:

> On Wed Sep 30, 2026 at 4:06 PM BST, Thorsten Leemhuis wrote:
>> On 9/29/26 13:47, Jens Axboe wrote:
>>> On Tue, 29 Sep 2026 11:33:58 +0200, Andreas Hindborg wrote:
>>>> I have a number of Rust block layer patches I would ask you to pick for
>>>> v7.4. I have collected them into a patch series as well as a pull request
>>>> so you can use whatever is easier.
>>>>
>>>> The changes cover
>>>>
>>>>  - Style and formatting changes.
>>>>  - Documentation fixes.
>>>>  - Fixes for missing trait bounds that can cause API unsoundness.
>>>>  - A change to set the owner of the file operations vtable in `GenDisk`.
>>>>  - Two bug fixes for the rnull driver.
>>>>
>>>> [...]
>>> 
>>> Applied, thanks!
>>>  [...]
>>
>> This series showed up in next today and broke the build for me on
>> various Fedora releases for aarch64 and x86_64; reverting this series
>> fixed that from a quick build test limited to drivers/block/rnull/
>>
>> The full error msg is quote long, find the top of it below. Full log:
>> https://download.copr.fedorainfracloud.org/results/@kernel-vanilla/next/fedora-rawhide-aarch64/11055137-next-next-all/builder-live.log.gz
>
> The `Child: Send` bound is introduced in configfs:
> https://lore.kernel.org/all/tencent_05937A22D2DA2BAE808EF19E491AA109BC09@qq.com/.
> So this is more or less a semantic conflict.

I did not consider the interactions of the two trees together. Good
thing we have linux-next.

> However, the fundamental issue is that TagSet never implements Send/Sync, which
> means that "rust: block: fix `Send` bound for `GenDisk`" will unconditionally
> strip away the Send implementation, which is problematic.
>
> Something like this should fix the issue:
>
>     unsafe impl<T: Operations<QueueData: Send>> Send for TagSet<T> {}
>     unsafe impl<T: Operations<QueueData: Send>> Sync for TagSet<T> {}
>
> That said, I am not sure why the GenDisk need to carry `Arc<TagSet<T>>: Send`
> bound in the first place. Removing it should also fix the issue.

`GenDisk<T>` has a field of type `Arc<TagSet<T>>`, so for `GenDisk` to be
send, so must `Arc<TagSet<T>>`. That `Arc` may be dropped with the
`GenDisk` if it is the last reference.

> Also, the `QueueData: Send` bound should be part of the `Operations` trait and
> not carried around everywhere.

`QueueData` is not involved here. An unconditional implementation is
fine. I submitted a patch here [1], hopefully Jens can pick it soon so
next can be unbroken tomorrow.

Best regards,
Andreas Hindborg

[1] https://lore.kernel.org/r/20260930-tag-set-send-sync-v1-1-51acdb36f4bb@kernel.org