Merge tag 'rust-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux

Pull Rust updates from Miguel Ojeda:
 "Toolchain and infrastructure:

   - Warn when using 'bindgen' < 0.72.1 with 'libclang' >= 22, since
     that combination may fail to build. It includes a probe for the bug
     in case 'bindgen' happens to be patched, and tests

     In parallel, Nathan updated the instructions for the kernel.org
     LLVM+Rust toolchains so that the latest version of 'bindgen' is
     installed, which should avoid some of these situations

   - Support testing 'rust_is_available.sh' with 'bash' as '/bin/sh'

   - Fix an objtool warning by adding one more 'noreturn' function for
     Rust 1.99.0 (expected 2026-10-01)

   - Fix build error in the 'rusttest' target due to ambiguity when the
     'rustc-dev' component is installed, which was uncovered by the work
     to support Rust's GCC backend ('rustc_codegen_gcc')

   - Fix future Clang warnings in the upcoming powerpc support due to
     macro redefinitions in the UAPI helper header by including the
     arch-aware 'ioctl.h' header

  'kernel' crate:

   - Rework module ownership support:

       - Move the module-related types into a new 'module' module and
         make the 'THIS_MODULE' pointer a constant of 'ModuleMetadata'
         so that modules can provide the pointer in const contexts, and
         add a 'this_module' 'const fn' to retrieve it

         This was enabled by upstream Rust's work on the 'const_mut_refs'
         and 'const_refs_to_static' features which were stabilized back
         in Rust 1.83.0

       - Teach '#[vtable]' to associate implementations with their
         owning module, defaulting to the local one, including fallbacks
         for doctests, uses within the 'kernel' crate (like upcoming
         KUnit '#[test]'s for DRM) and 'rusttest'

       - Set 'fops.owner' from the module pointer for DRM and
         miscdevice

       - Migrate Rust Binder and configfs away from the old
         'THIS_MODULE' 'static' and finally remove it from the 'module!'
         macro

   - 'num' module:

       - Add the new 'casts' module for lossless integer conversions

         Rust's 'core' library's 'From' implementations do not cover
         conversions that are not portable or future-proof. However, the
         kernel supports a narrower set of architectures, which makes it
         helpful to provide more infallible conversions, instead of
         having developers use 'as' casts, which carry the risk of
         silently losing data

         This goes along with previous work we did to avoid casts in
         Rust kernel code since they are more powerful than needed

         Thus, provide safe 'const' conversion functions (e.g.
         'usize_as_u64' and 'u64_into_u8'), as well as the
         'FromSafeCast' and 'IntoSafeCast' extension traits that provide
         conversions that are known to be lossless in the kernel, and an
         'arch' submodule defining conversions that are known to be
         lossless on particular architectures (e.g. 64-bit platforms).
         For instance:

             // Conversion in const context.
             const USIZED_CONST: usize = u8_as_usize(255u8);

             // Non-const conversions.
             let a = u64::from_safe_cast(4096usize);
             let b: u64 = 4096usize.into_safe_cast();

       - Add 'Bounded::shr_exact' method in the vein of 'try_shrink'
         which shifts a bounded right only if it loses no set bits

       - Fix unsoundness issue in the 'Bounded::shr' method by
         rejecting, at compile-time, shifts of at least the type's bit
         width

   - 'fmt' module:

       - Route '{:p}' raw pointer formatting through the kernel's hashed
         '%p' format to prevent address leaks, including support for
         width and padding. Include tests for both 'no_hash_pointers'
         case and the default (hashed) one

       - Fix the '{:p}' forwarding implementation, which could print the
         address of a temporary stack variable

   - 'time' module:

       - Make 'Delta' generic over its time unit, with a default unit of
         nanoseconds ('Nsec'), preserving the existing behavior. Then,
         add a 'Jiffy' time unit

       - Add the 'Delta::as_millis_ceil()' method

       - Fix 'as_micros_ceil()' rounding near 'i64::MAX', which could
         yield a result one microsecond too small

   - 'sync' module:

       - Implement 'ForeignOwnable' for 'ARef<T>', allowing C code to
         own an 'ARef<T>'

       - Add a safe abstraction for 'rcu_barrier()'

   - 'error' module: add all of the remaining error codes, except the
     deprecated compatibility aliases

   - 'bug' module:

       - Fix build error on UML in 'warn_on!' for callers from within
         the 'kernel' crate

       - Fix future 'dead_code' warning on arm and loongarch64 and under
         'CONFIG_BUG=n' in 'warn_on!', which would trigger with the
         upcoming SRCU abstractions

       - Fix future build error in 'rusttest' on cross-compilation
         cases, which would trigger when 'warn_on!' has callers inside
         the 'kernel' crate

   - 'bitfield' module: fix build error for the upcoming support for
     Rust's GCC backend ('rustc_codegen_gcc') by always inlining a
     couple conversions used in tests

  'pin-init' crate:

   - User-visible changes:

       - Merge the '__pinned_init' and '__init' methods and make 'Init'
         a marker trait

       - Introduce public APIs 'raw_init' and 'raw_try_init' to prevent
         users from needing to invoke the internal '__pinned_init' and
         '__init' methods

       - Emit errors for duplicate '#[pin]' attributes

       - Link 'Zeroable::zeroed' and 'pin_init::zeroed' in documentation

   - Other changes:

       - Fix unwind safety issues

       - Clean up lint 'allow' and 'expect's

       - Overhaul '#[cfg]' handling to pave the way for tuple structs
         and self-referential structs

       - Mark many functions as '#[inline]' for better codegen with '-C
         opt-level=s' ('CC_OPTIMIZE_FOR_SIZE')

  'MAINTAINERS':

   - Update 'MODULE SUPPORT' to cover the new 'module' module

  And some other fixes, cleanups and improvements"

* tag 'rust-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (54 commits)
  rust: add functions and traits for lossless integer conversions
  rust: kernel: add `LocalModule` fallback for `#[vtable]` `impl`s
  rust: fmt: route {:p} through HashedPtr to prevent address leaks
  rust: fmt: fix {:p} printing stack addresses
  rust: module: update MAINTAINERS to cover module.rs
  rust: macros: remove `THIS_MODULE` static from `module!`
  rust_binder: use `LocalModule` for `THIS_MODULE`
  rust: configfs: use `LocalModule` for `THIS_MODULE`
  rust: miscdevice: set fops.owner from driver module pointer
  rust: drm: set fops.owner from driver module pointer
  rust: macros: auto-insert OwnerModule in #[vtable]
  rust: doctest: add LocalModule fallback for #[vtable] ThisModule
  rust: module: add `THIS_MODULE` const to `ModuleMetadata` trait
  rust: module: move module types into `module.rs`
  rust: num: add Bounded::shr_exact
  rust: num: reject Bounded::shr overshifts at build time
  rust: num: use const_assert! in Bounded
  rust: uapi: replace direct asm-generic/ioctl.h include with linux/ioctl.h
  rust: time: add Delta::as_millis_ceil()
  rust: time: add jiffies time unit for Delta
  ...

32 files changed, 998 insertions, 152 deletions

diff --git a/rust/kernel/alloc/kbox.rs b/rust/kernel/alloc/kbox.rs
index 35d1e015848d..c63d6acdbb6f 100644
--- a/rust/kernel/alloc/kbox.rs
+++ b/rust/kernel/alloc/kbox.rs
@@ -372,13 +372,13 @@ where
             // - `ptr` is a valid pointer to uninitialized memory.
             // - `ptr` is not used if an error is returned.
             // - `ptr` won't be moved until it is dropped, i.e. it is pinned.
-            unsafe { init(i).__pinned_init(ptr)? };
+            unsafe { pin_init::raw_try_init(ptr, init(i))? };
 
             // SAFETY:
             // - `i + 1 <= len`, hence we don't exceed the capacity, due to the call to
             //   `with_capacity()` above.
             // - The new value at index buffer.len() + 1 is the only element being added here, and
-            //   it has been initialized above by `init(i).__pinned_init(ptr)`.
+            //   it has been initialized above by `raw_try_init(ptr, i)`.
             unsafe { buffer.inc_len(1) };
         }
 
@@ -463,7 +463,7 @@ where
         let slot = self.as_mut_ptr();
         // SAFETY: When init errors/panics, slot will get deallocated but not dropped,
         // slot is valid.
-        unsafe { init.__init(slot)? };
+        unsafe { pin_init::raw_try_init(slot, init)? };
         // SAFETY: All fields have been initialized.
         Ok(unsafe { Box::assume_init(self) })
     }
@@ -473,7 +473,7 @@ where
         let slot = self.as_mut_ptr();
         // SAFETY: When init errors/panics, slot will get deallocated but not dropped,
         // slot is valid and will not be moved, because we pin it later.
-        unsafe { init.__pinned_init(slot)? };
+        unsafe { pin_init::raw_try_init(slot, init)? };
         // SAFETY: All fields have been initialized.
         Ok(unsafe { Box::assume_init(self) }.into())
     }
diff --git a/rust/kernel/auxiliary.rs b/rust/kernel/auxiliary.rs
index c42928d5a239..cc9745fbf179 100644
--- a/rust/kernel/auxiliary.rs
+++ b/rust/kernel/auxiliary.rs
@@ -69,7 +69,7 @@ unsafe impl<T: Driver> driver::RegistrationOps for Adapter<T> {
 
         // SAFETY: `adrv` is guaranteed to be a valid `DriverType`.
         to_result(unsafe {
-            bindings::__auxiliary_driver_register(adrv.get(), module.0, name.as_char_ptr())
+            bindings::__auxiliary_driver_register(adrv.get(), module.as_ptr(), name.as_char_ptr())
         })
     }
 
diff --git a/rust/kernel/bitfield.rs b/rust/kernel/bitfield.rs
index 35ede53f2b8e..a0d089423f21 100644
--- a/rust/kernel/bitfield.rs
+++ b/rust/kernel/bitfield.rs
@@ -581,6 +581,7 @@ mod tests {
     }
 
     impl From<MemoryType> for Bounded<u64, 4> {
+        #[inline(always)]
         fn from(mt: MemoryType) -> Bounded<u64, 4> {
             Bounded::from_expr(mt as u64)
         }
@@ -606,6 +607,7 @@ mod tests {
     }
 
     impl From<Priority> for Bounded<u16, 2> {
+        #[inline(always)]
         fn from(p: Priority) -> Bounded<u16, 2> {
             Bounded::from_expr(p as u16)
         }
diff --git a/rust/kernel/bug.rs b/rust/kernel/bug.rs
index ed943960f851..3566f0234ca4 100644
--- a/rust/kernel/bug.rs
+++ b/rust/kernel/bug.rs
@@ -8,6 +8,7 @@
 
 #[macro_export]
 #[doc(hidden)]
+#[cfg(not(testlib))]
 #[cfg(all(CONFIG_BUG, not(CONFIG_UML), not(CONFIG_LOONGARCH), not(CONFIG_ARM)))]
 #[cfg(CONFIG_DEBUG_BUGVERBOSE)]
 macro_rules! warn_flags {
@@ -47,12 +48,17 @@ macro_rules! warn_flags {
 
 #[macro_export]
 #[doc(hidden)]
+#[cfg(not(testlib))]
 #[cfg(all(CONFIG_BUG, not(CONFIG_UML), not(CONFIG_LOONGARCH), not(CONFIG_ARM)))]
 #[cfg(not(CONFIG_DEBUG_BUGVERBOSE))]
 macro_rules! warn_flags {
     ($file:expr, $flags:expr) => {
         const FLAGS: u32 = $crate::bindings::BUGFLAG_WARNING | $flags;
 
+        if false {
+            _ = $file;
+        }
+
         // SAFETY:
         // - `flags` and `size` are all compile-time constants, preventing
         // any invalid memory access.
@@ -73,14 +79,19 @@ macro_rules! warn_flags {
 
 #[macro_export]
 #[doc(hidden)]
+#[cfg(not(testlib))]
 #[cfg(all(CONFIG_BUG, CONFIG_UML))]
 macro_rules! warn_flags {
     ($file:expr, $flags:expr) => {
+        if false {
+            _ = $file;
+        }
+
         // SAFETY: It is always safe to call `warn_slowpath_fmt()`
         // with a valid null-terminated string.
         unsafe {
             $crate::bindings::warn_slowpath_fmt(
-                $crate::c_str!(::core::file!()).as_char_ptr(),
+                $crate::str::CStrExt::as_char_ptr($crate::c_str!(::core::file!())),
                 line!() as $crate::ffi::c_int,
                 $flags as $crate::ffi::c_uint,
                 ::core::ptr::null(),
@@ -91,9 +102,15 @@ macro_rules! warn_flags {
 
 #[macro_export]
 #[doc(hidden)]
+#[cfg(not(testlib))]
 #[cfg(all(CONFIG_BUG, any(CONFIG_LOONGARCH, CONFIG_ARM)))]
 macro_rules! warn_flags {
     ($file:expr, $flags:expr) => {
+        if false {
+            _ = $file;
+            _ = $flags;
+        }
+
         // SAFETY: It is always safe to call `WARN_ON()`.
         unsafe { $crate::bindings::WARN_ON(true) }
     };
@@ -101,9 +118,14 @@ macro_rules! warn_flags {
 
 #[macro_export]
 #[doc(hidden)]
-#[cfg(not(CONFIG_BUG))]
+#[cfg(any(testlib, not(CONFIG_BUG)))]
 macro_rules! warn_flags {
-    ($file:expr, $flags:expr) => {};
+    ($file:expr, $flags:expr) => {
+        if false {
+            _ = $file;
+            _ = $flags;
+        }
+    };
 }
 
 #[doc(hidden)]
@@ -118,14 +140,14 @@ macro_rules! warn_on {
         let cond = $cond;
 
         #[cfg(CONFIG_DEBUG_BUGVERBOSE_DETAILED)]
-        const _COND_STR: &str = concat!("[", stringify!($cond), "] ", file!());
+        const COND_STR: &str = concat!("[", stringify!($cond), "] ", file!());
         #[cfg(not(CONFIG_DEBUG_BUGVERBOSE_DETAILED))]
-        const _COND_STR: &str = file!();
+        const COND_STR: &str = file!();
 
         if cond {
             const WARN_ON_FLAGS: u32 = $crate::bug::bugflag_taint($crate::bindings::TAINT_WARN);
 
-            $crate::warn_flags!(_COND_STR, WARN_ON_FLAGS);
+            $crate::warn_flags!(COND_STR, WARN_ON_FLAGS);
         }
         cond
     }};
diff --git a/rust/kernel/configfs.rs b/rust/kernel/configfs.rs
index 2339c6467325..cd082b83e9e7 100644
--- a/rust/kernel/configfs.rs
+++ b/rust/kernel/configfs.rs
@@ -875,13 +875,14 @@ impl<Container, Data> ItemType<Container, Data> {
 ///                 configfs::Subsystem<Configuration>,
 ///                 Configuration
 ///                 >::new_with_child_ctor::<N,Child>(
-///             &THIS_MODULE,
+///             ::kernel::module::this_module::<crate::LocalModule>(),
 ///             &CONFIGURATION_ATTRS
 ///         );
 ///
 ///     &CONFIGURATION_TPE
 /// }
 /// ```
+#[allow(clippy::crate_in_macro_def)]
 #[macro_export]
 macro_rules! configfs_attrs {
     (
@@ -1021,7 +1022,8 @@ macro_rules! configfs_attrs {
 
                     static [< $data:upper _TPE >] : $crate::configfs::ItemType<$container, $data>  =
                         $crate::configfs::ItemType::<$container, $data>::new::<N>(
-                            &THIS_MODULE, &[<$ data:upper _ATTRS >]
+                            $crate::module::this_module::<crate::LocalModule>(),
+                            &[<$ data:upper _ATTRS >]
                         );
                 )?
 
@@ -1030,7 +1032,8 @@ macro_rules! configfs_attrs {
                         $crate::configfs::ItemType<$container, $data>  =
                             $crate::configfs::ItemType::<$container, $data>::
                             new_with_child_ctor::<N, $child>(
-                                &THIS_MODULE, &[<$ data:upper _ATTRS >]
+                                $crate::module::this_module::<crate::LocalModule>(),
+                                &[<$ data:upper _ATTRS >]
                             );
                 )?
 
diff --git a/rust/kernel/dma.rs b/rust/kernel/dma.rs
index 200def84fb69..8e36a4e7f514 100644
--- a/rust/kernel/dma.rs
+++ b/rust/kernel/dma.rs
@@ -449,7 +449,7 @@ impl<T: AsBytes + FromBytes> CoherentBox<[T]> {
         // - `T: AsBytes + FromBytes` guarantees all bit patterns are valid, so partial writes on
         //   error cannot leave the element in an invalid state.
         // - The DMA address has not been exposed yet, so there is no concurrent device access.
-        unsafe { init.__init(ptr)? };
+        unsafe { pin_init::raw_try_init(ptr, init)? };
 
         Ok(())
     }
@@ -791,10 +791,10 @@ impl<T: AsBytes + FromBytes> Coherent<T> {
 
         // SAFETY:
         // - `ptr` is valid, properly aligned, and points to exclusively owned memory.
-        // - If `__init` fails, `self` is dropped, which safely frees the underlying `Coherent`'s
-        //   DMA memory. `T: AsBytes + FromBytes` ensures there are no complex `Drop` requirements
-        //   we are bypassing.
-        unsafe { init.__init(ptr)? };
+        // - If `raw_try_init` fails, `self` is dropped, which safely frees the underlying
+        //   `Coherent`'s DMA memory. `T: AsBytes + FromBytes` ensures there are no complex `Drop`
+        //   requirements we are bypassing.
+        unsafe { pin_init::raw_try_init(ptr, init)? };
 
         Ok(dmem)
     }
diff --git a/rust/kernel/drm/device.rs b/rust/kernel/drm/device.rs
index 477cf771fb10..81f9f7e59817 100644
--- a/rust/kernel/drm/device.rs
+++ b/rust/kernel/drm/device.rs
@@ -203,7 +203,8 @@ impl<T: drm::Driver> UnregisteredDevice<T> {
         fops: &Self::GEM_FOPS,
     };
 
-    const GEM_FOPS: bindings::file_operations = drm::gem::create_fops();
+    const GEM_FOPS: bindings::file_operations =
+        drm::gem::create_fops(crate::module::this_module::<T::OwnerModule>().as_ptr());
 
     /// Create a new `UnregisteredDevice` for a `drm::Driver`.
     ///
@@ -244,7 +245,7 @@ impl<T: drm::Driver> UnregisteredDevice<T> {
         // SAFETY:
         // - `raw_data` is a valid pointer to uninitialized memory.
         // - `raw_data` will not move until it is dropped.
-        unsafe { data.__pinned_init(raw_data) }.inspect_err(|_| {
+        unsafe { pin_init::raw_try_init(raw_data, data) }.inspect_err(|_| {
             // SAFETY: `__drm_dev_alloc()` was successful, hence `drm_dev` must be valid and the
             // refcount must be non-zero.
             unsafe { bindings::drm_dev_put(drm_dev) };
diff --git a/rust/kernel/drm/gem/mod.rs b/rust/kernel/drm/gem/mod.rs
index c8b66d816871..a7ba1453d40b 100644
--- a/rust/kernel/drm/gem/mod.rs
+++ b/rust/kernel/drm/gem/mod.rs
@@ -387,10 +387,10 @@ impl<T: DriverObject, Ctx: DeviceContext> AllocImpl for Object<T, Ctx> {
     };
 }
 
-pub(super) const fn create_fops() -> bindings::file_operations {
+pub(super) const fn create_fops(owner: *mut bindings::module) -> bindings::file_operations {
     let mut fops: bindings::file_operations = pin_init::zeroed();
 
-    fops.owner = core::ptr::null_mut();
+    fops.owner = owner;
     fops.open = Some(bindings::drm_open);
     fops.release = Some(bindings::drm_release);
     fops.unlocked_ioctl = Some(bindings::drm_ioctl);
diff --git a/rust/kernel/drm/gpuvm/va.rs b/rust/kernel/drm/gpuvm/va.rs
index 0b09fe44ab39..bf927b8e6fbb 100644
--- a/rust/kernel/drm/gpuvm/va.rs
+++ b/rust/kernel/drm/gpuvm/va.rs
@@ -116,7 +116,7 @@ impl<T: DriverGpuVm> GpuVaAlloc<T> {
     pub(super) fn prepare(mut self, va_data: impl PinInit<T::VaData>) -> *mut bindings::drm_gpuva {
         let va_ptr = MaybeUninit::as_mut_ptr(&mut self.0);
         // SAFETY: The `data` field is pinned.
-        let Ok(()) = unsafe { va_data.__pinned_init(&raw mut (*va_ptr).data) };
+        unsafe { pin_init::raw_init(&raw mut (*va_ptr).data, va_data) };
         KBox::into_raw(self.0).cast()
     }
 }
diff --git a/rust/kernel/drm/gpuvm/vm_bo.rs b/rust/kernel/drm/gpuvm/vm_bo.rs
index c064ac63897b..ab12b710267e 100644
--- a/rust/kernel/drm/gpuvm/vm_bo.rs
+++ b/rust/kernel/drm/gpuvm/vm_bo.rs
@@ -181,7 +181,7 @@ impl<T: DriverGpuVm> GpuVmBoAlloc<T> {
         };
         let ptr = NonNull::new(raw_ptr).ok_or(AllocError)?;
         // SAFETY: `ptr->data` is a valid pinned location.
-        let Ok(()) = unsafe { value.__pinned_init(&raw mut (*raw_ptr).data) };
+        unsafe { pin_init::raw_init(&raw mut (*raw_ptr).data, value) };
         // INVARIANTS: We just created the vm_bo so it's absent from lists, and the data is valid
         // as we just initialized it.
         Ok(GpuVmBoAlloc(ptr))
diff --git a/rust/kernel/error.rs b/rust/kernel/error.rs
index a56ba6309594..e52793f77196 100644
--- a/rust/kernel/error.rs
+++ b/rust/kernel/error.rs
@@ -30,6 +30,7 @@ pub mod code {
         };
     }
 
+    // From `include/uapi/asm-generic/errno-base.h`.
     declare_err!(EPERM, "Operation not permitted.");
     declare_err!(ENOENT, "No such file or directory.");
     declare_err!(ESRCH, "No such process.");
@@ -64,9 +65,110 @@ pub mod code {
     declare_err!(EPIPE, "Broken pipe.");
     declare_err!(EDOM, "Math argument out of domain of func.");
     declare_err!(ERANGE, "Math result not representable.");
+
+    // From `include/uapi/asm-generic/errno.h`.
+    declare_err!(EDEADLK, "Resource deadlock would occur.");
+    declare_err!(ENAMETOOLONG, "File name too long.");
+    declare_err!(ENOLCK, "No record locks available.");
+    declare_err!(ENOSYS, "Invalid system call number.");
+    declare_err!(ENOTEMPTY, "Directory not empty.");
+    declare_err!(ELOOP, "Too many symbolic links encountered.");
+    declare_err!(ENOMSG, "No message of desired type.");
+    declare_err!(EIDRM, "Identifier removed.");
+    declare_err!(ECHRNG, "Channel number out of range.");
+    declare_err!(EL2NSYNC, "Level 2 not synchronized.");
+    declare_err!(EL3HLT, "Level 3 halted.");
+    declare_err!(EL3RST, "Level 3 reset.");
+    declare_err!(ELNRNG, "Link number out of range.");
+    declare_err!(EUNATCH, "Protocol driver not attached.");
+    declare_err!(ENOCSI, "No CSI structure available.");
+    declare_err!(EL2HLT, "Level 2 halted.");
+    declare_err!(EBADE, "Invalid exchange.");
+    declare_err!(EBADR, "Invalid request descriptor.");
+    declare_err!(EXFULL, "Exchange full.");
+    declare_err!(ENOANO, "No anode.");
+    declare_err!(EBADRQC, "Invalid request code.");
+    declare_err!(EBADSLT, "Invalid slot.");
+    declare_err!(EBFONT, "Bad font file format.");
+    declare_err!(ENOSTR, "Device not a stream.");
+    declare_err!(ENODATA, "No data available.");
+    declare_err!(ETIME, "Timer expired.");
+    declare_err!(ENOSR, "Out of streams resources.");
+    declare_err!(ENONET, "Machine is not on the network.");
+    declare_err!(ENOPKG, "Package not installed.");
+    declare_err!(EREMOTE, "Object is remote.");
+    declare_err!(ENOLINK, "Link has been severed.");
+    declare_err!(EADV, "Advertise error.");
+    declare_err!(ESRMNT, "Srmount error.");
+    declare_err!(ECOMM, "Communication error on send.");
+    declare_err!(EPROTO, "Protocol error.");
+    declare_err!(EMULTIHOP, "Multihop attempted.");
+    declare_err!(EDOTDOT, "RFS specific error.");
+    declare_err!(EBADMSG, "Not a data message.");
+    declare_err!(EFSBADCRC, "Bad CRC detected.");
     declare_err!(EOVERFLOW, "Value too large for defined data type.");
+    declare_err!(ENOTUNIQ, "Name not unique on network.");
+    declare_err!(EBADFD, "File descriptor in bad state.");
+    declare_err!(EREMCHG, "Remote address changed.");
+    declare_err!(ELIBACC, "Can not access a needed shared library.");
+    declare_err!(ELIBBAD, "Accessing a corrupted shared library.");
+    declare_err!(ELIBSCN, ".lib section in a.out corrupted.");
+    declare_err!(ELIBMAX, "Attempting to link in too many shared libraries.");
+    declare_err!(ELIBEXEC, "Cannot exec a shared library directly.");
+    declare_err!(EILSEQ, "Illegal byte sequence.");
+    declare_err!(ERESTART, "Interrupted system call should be restarted.");
+    declare_err!(ESTRPIPE, "Streams pipe error.");
+    declare_err!(EUSERS, "Too many users.");
+    declare_err!(ENOTSOCK, "Socket operation on non-socket.");
+    declare_err!(EDESTADDRREQ, "Destination address required.");
     declare_err!(EMSGSIZE, "Message too long.");
+    declare_err!(EPROTOTYPE, "Protocol wrong type for socket.");
+    declare_err!(ENOPROTOOPT, "Protocol not available.");
+    declare_err!(EPROTONOSUPPORT, "Protocol not supported.");
+    declare_err!(ESOCKTNOSUPPORT, "Socket type not supported.");
+    declare_err!(EOPNOTSUPP, "Operation not supported on transport endpoint.");
+    declare_err!(EPFNOSUPPORT, "Protocol family not supported.");
+    declare_err!(EAFNOSUPPORT, "Address family not supported by protocol.");
+    declare_err!(EADDRINUSE, "Address already in use.");
+    declare_err!(EADDRNOTAVAIL, "Cannot assign requested address.");
+    declare_err!(ENETDOWN, "Network is down.");
+    declare_err!(ENETUNREACH, "Network is unreachable.");
+    declare_err!(ENETRESET, "Network dropped connection because of reset.");
+    declare_err!(ECONNABORTED, "Software caused connection abort.");
+    declare_err!(ECONNRESET, "Connection reset by peer.");
+    declare_err!(ENOBUFS, "No buffer space available.");
+    declare_err!(EISCONN, "Transport endpoint is already connected.");
+    declare_err!(ENOTCONN, "Transport endpoint is not connected.");
+    declare_err!(ESHUTDOWN, "Cannot send after transport endpoint shutdown.");
+    declare_err!(ETOOMANYREFS, "Too many references: cannot splice.");
     declare_err!(ETIMEDOUT, "Connection timed out.");
+    declare_err!(ECONNREFUSED, "Connection refused.");
+    declare_err!(EHOSTDOWN, "Host is down.");
+    declare_err!(EHOSTUNREACH, "No route to host.");
+    declare_err!(EALREADY, "Operation already in progress.");
+    declare_err!(EINPROGRESS, "Operation now in progress.");
+    declare_err!(ESTALE, "Stale file handle.");
+    declare_err!(EUCLEAN, "Structure needs cleaning.");
+    declare_err!(EFSCORRUPTED, "Filesystem is corrupted.");
+    declare_err!(ENOTNAM, "Not a XENIX named type file.");
+    declare_err!(ENAVAIL, "No XENIX semaphores available.");
+    declare_err!(EISNAM, "Is a named type file.");
+    declare_err!(EREMOTEIO, "Remote I/O error.");
+    declare_err!(EDQUOT, "Quota exceeded.");
+    declare_err!(ENOMEDIUM, "No medium found.");
+    declare_err!(EMEDIUMTYPE, "Wrong medium type.");
+    declare_err!(ECANCELED, "Operation Canceled.");
+    declare_err!(ENOKEY, "Required key not available.");
+    declare_err!(EKEYEXPIRED, "Key has expired.");
+    declare_err!(EKEYREVOKED, "Key has been revoked.");
+    declare_err!(EKEYREJECTED, "Key was rejected by service.");
+    declare_err!(EOWNERDEAD, "Owner died.");
+    declare_err!(ENOTRECOVERABLE, "State not recoverable.");
+    declare_err!(ERFKILL, "Operation not possible due to RF-kill.");
+    declare_err!(EHWPOISON, "Memory page has hardware error.");
+    declare_err!(EFTYPE, "Wrong file type for the intended operation.");
+
+    // From `include/linux/errno.h`.
     declare_err!(ERESTARTSYS, "Restart the system call.");
     declare_err!(ERESTARTNOINTR, "System call was interrupted by a signal and will be restarted.");
     declare_err!(ERESTARTNOHAND, "Restart if no handler.");
diff --git a/rust/kernel/fmt.rs b/rust/kernel/fmt.rs
index 73afbc51ba33..29582b053ab1 100644
--- a/rust/kernel/fmt.rs
+++ b/rust/kernel/fmt.rs
@@ -4,6 +4,8 @@
 //!
 //! This module is intended to be used in place of `core::fmt` in kernel code.
 
+use kernel::prelude::*;
+
 pub use core::fmt::{
     Arguments,
     Debug,
@@ -39,11 +41,115 @@ use core::fmt::{
     LowerExp,
     LowerHex,
     Octal,
-    Pointer,
     UpperExp,
     UpperHex, //
 };
-impl_fmt_adapter_forward!(Debug, LowerHex, UpperHex, Octal, Binary, Pointer, LowerExp, UpperExp);
+use core::ptr::NonNull;
+impl_fmt_adapter_forward!(Debug, LowerHex, UpperHex, Octal, Binary, LowerExp, UpperExp);
+
+/// A copy of [`core::fmt::Pointer`] that allows implementing pointer formatting for foreign types.
+///
+/// Together with the [`Adapter`] type and [`fmt!`] macro, it enables raw pointer formatting to be
+/// intercepted and routed to [`HashedPtr`] (kernel's `%p` hashed format), preventing kernel address
+/// leaks.
+///
+/// [`fmt!`]: crate::prelude::fmt!
+pub trait Pointer {
+    /// Same as [`core::fmt::Pointer::fmt`].
+    fn fmt(&self, f: &mut Formatter<'_>) -> Result;
+}
+
+/// A wrapper for pointers that formats them using kernel's `%p` format specifier.
+///
+/// By default, `%p` prints a hashed representation of the pointer address to prevent kernel address
+/// leaks. When the `no_hash_pointers` kernel command-line parameter is enabled, the real address is
+/// printed instead (for debugging purposes).
+pub struct HashedPtr<T: ?Sized>(pub *const T);
+
+impl<T: ?Sized> Pointer for HashedPtr<T> {
+    fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+        use crate::str::CStrExt as _;
+
+        let mut buf = [0u8; 32];
+
+        // Use `%#0*p` for the `0x` prefix and zero-padding; `+2` compensates for
+        // the prefix counting toward the field width.
+        let default_width = (2 * size_of::<usize>() + 2) as c_int;
+        let width = match (f.sign_aware_zero_pad(), f.width()) {
+            (true, Some(w)) if w > 0 => w.min(buf.len() - 1) as c_int,
+            _ => default_width,
+        };
+
+        // SAFETY: `buf` is a valid, writable 32-byte buffer, sufficient for
+        // all architectures (max 19 bytes for 64-bit under the default width).
+        // The format string is null-terminated; `width` (c_int) and pointer
+        // match the `%*` and `%p` specifiers.
+        let len = unsafe {
+            crate::bindings::scnprintf(
+                buf.as_mut_ptr().cast(),
+                buf.len(),
+                c"%#0*p".as_char_ptr(),
+                width,
+                self.0.cast::<c_void>(),
+            )
+        };
+
+        // SAFETY: `%#0*p` produces only ASCII, which is valid UTF-8.
+        let s = unsafe { core::str::from_utf8_unchecked(&buf[..len as usize]) };
+
+        if f.sign_aware_zero_pad() {
+            // `scnprintf` already applied the width and zero-padding via `%#0*p`.
+            f.write_str(s)
+        } else {
+            f.pad(s)
+        }
+    }
+}
+
+// Raw pointers are formatted via `HashedPtr` (kernel `%p`: hashed by default, plain with
+// `no_hash_pointers`).
+impl<T: ?Sized> Pointer for *const T {
+    #[inline]
+    fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+        Pointer::fmt(&HashedPtr(*self), f)
+    }
+}
+
+impl<T: ?Sized> Pointer for *mut T {
+    #[inline]
+    fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+        Pointer::fmt(&HashedPtr(*self), f)
+    }
+}
+
+impl<T: ?Sized> Pointer for &T {
+    #[inline]
+    fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+        Pointer::fmt(&HashedPtr(*self), f)
+    }
+}
+
+impl<T: ?Sized> Pointer for &mut T {
+    #[inline]
+    fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+        Pointer::fmt(&HashedPtr(core::ptr::from_ref(*self)), f)
+    }
+}
+
+impl<T: ?Sized> Pointer for NonNull<T> {
+    #[inline]
+    fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+        Pointer::fmt(&HashedPtr(self.as_ptr()), f)
+    }
+}
+
+// `Adapter<&T>` bridges our `Pointer` trait to `core::fmt::Pointer`
+impl<T: Pointer> core::fmt::Pointer for Adapter<&T> {
+    #[inline]
+    fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+        Pointer::fmt(self.0, f)
+    }
+}
 
 /// A copy of [`core::fmt::Display`] that allows us to implement it for foreign types.
 ///
@@ -105,3 +211,88 @@ impl_display_forward!(
     {<T: ?Sized>} crate::sync::Arc<T> {where crate::sync::Arc<T>: core::fmt::Display},
     {<T: ?Sized>} crate::sync::UniqueArc<T> {where crate::sync::UniqueArc<T>: core::fmt::Display},
 );
+
+#[macros::kunit_tests(rust_kernel_fmt)]
+mod tests {
+    use crate::{
+        bindings,
+        prelude::fmt,
+        str::CString, //
+    };
+
+    #[cfg(CONFIG_64BIT)]
+    mod expected {
+        pub(super) const PTR_VALUE: usize = 0xffffffffdeadbeef;
+        pub(super) const PTR_VAL_NO_CRNG: &str = "(____ptrval____)";
+        pub(super) const HASHED_PREFIX: &str = "0x00000000";
+        pub(super) const RAW_POINTER: &str = "0xffffffffdeadbeef";
+        pub(super) const PADDED_RIGHT: &str = "      0xffffffffdeadbeef";
+        pub(super) const ZERO_PADDED: &str = "0x000000ffffffffdeadbeef";
+        pub(super) const HASHED_PADDED_RIGHT_PREFIX: &str = "      ";
+        pub(super) const HASHED_ZERO_PADDED_PREFIX: &str = "0x00000000000000";
+        pub(super) const CLAMPED: &str = "0x0000000000000ffffffffdeadbeef";
+    }
+
+    #[cfg(not(CONFIG_64BIT))]
+    mod expected {
+        pub(super) const PTR_VALUE: usize = 0xdeadbeef;
+        pub(super) const PTR_VAL_NO_CRNG: &str = "(ptrval)";
+        pub(super) const HASHED_PREFIX: &str = "0x";
+        pub(super) const RAW_POINTER: &str = "0xdeadbeef";
+        pub(super) const PADDED_RIGHT: &str = "              0xdeadbeef";
+        pub(super) const ZERO_PADDED: &str = "0x00000000000000deadbeef";
+        pub(super) const HASHED_PADDED_RIGHT_PREFIX: &str = "              ";
+        pub(super) const HASHED_ZERO_PADDED_PREFIX: &str = "0x00000000000000";
+        pub(super) const CLAMPED: &str = "0x0000000000000000000000deadbeef";
+    }
+
+    #[test]
+    fn test_ptr_formatting() -> core::result::Result<(), crate::error::Error> {
+        let ptr: *const u8 = core::ptr::without_provenance(expected::PTR_VALUE);
+
+        // SAFETY: `no_hash_pointers` is a global variable that is never concurrently modified —
+        // KUnit tests may run at boot (before `mark_readonly()`) or manually afterwards (when the
+        // variable is read-only). Reading is always safe.
+        let no_hash = unsafe { bindings::no_hash_pointers };
+
+        if no_hash {
+            let cstr = CString::try_from_fmt(fmt!("{:p}", ptr))?;
+            assert_eq!(cstr.to_str()?, expected::RAW_POINTER);
+
+            let cstr = CString::try_from_fmt(fmt!("{:>24p}", ptr))?;
+            assert_eq!(cstr.to_str()?, expected::PADDED_RIGHT);
+
+            let cstr = CString::try_from_fmt(fmt!("{:024p}", ptr))?;
+            assert_eq!(cstr.to_str()?, expected::ZERO_PADDED);
+
+            let cstr = CString::try_from_fmt(fmt!("{:0100p}", ptr))?;
+            assert_eq!(cstr.to_str()?, expected::CLAMPED);
+        } else {
+            let cstr = CString::try_from_fmt(fmt!("{:p}", ptr))?;
+            let formatted = cstr.to_str()?;
+            // If the RNG is not yet ready, `%p` falls back to a placeholder.
+            if formatted == expected::PTR_VAL_NO_CRNG {
+                return Ok(());
+            }
+            assert!(formatted.starts_with(expected::HASHED_PREFIX));
+            assert_ne!(formatted, expected::RAW_POINTER);
+
+            let cstr = CString::try_from_fmt(fmt!("{:>24p}", ptr))?;
+            assert!(cstr
+                .to_str()?
+                .starts_with(expected::HASHED_PADDED_RIGHT_PREFIX));
+
+            let cstr = CString::try_from_fmt(fmt!("{:024p}", ptr))?;
+            assert!(cstr
+                .to_str()?
+                .starts_with(expected::HASHED_ZERO_PADDED_PREFIX));
+
+            let cstr = CString::try_from_fmt(fmt!("{:0100p}", ptr))?;
+            let output = cstr.to_str()?;
+            assert!(output.starts_with("0x"));
+            assert!(!output[2..].chars().all(|c| c == '0'));
+        }
+
+        Ok(())
+    }
+}
diff --git a/rust/kernel/i2c.rs b/rust/kernel/i2c.rs
index 624b971ca8b0..dd9271af5eb8 100644
--- a/rust/kernel/i2c.rs
+++ b/rust/kernel/i2c.rs
@@ -142,7 +142,7 @@ unsafe impl<T: Driver> driver::RegistrationOps for Adapter<T> {
         }
 
         // SAFETY: `idrv` is guaranteed to be a valid `DriverType`.
-        to_result(unsafe { bindings::i2c_register_driver(module.0, idrv.get()) })
+        to_result(unsafe { bindings::i2c_register_driver(module.as_ptr(), idrv.get()) })
     }
 
     unsafe fn unregister(idrv: &Opaque<Self::DriverType>) {
diff --git a/rust/kernel/impl_flags.rs b/rust/kernel/impl_flags.rs
index e2bd7639da12..fdf44d5eea9c 100644
--- a/rust/kernel/impl_flags.rs
+++ b/rust/kernel/impl_flags.rs
@@ -19,7 +19,10 @@
 /// # Examples
 ///
 /// ```
-/// use kernel::impl_flags;
+/// use kernel::{
+///     bits::bit_u32,
+///     impl_flags, //
+/// };
 ///
 /// impl_flags!(
 ///     /// Represents multiple permissions.
@@ -30,13 +33,13 @@
 ///     #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 ///     pub enum Permission {
 ///         /// Read permission.
-///         Read = 1 << 0,
+///         Read = bit_u32(0),
 ///
 ///         /// Write permission.
-///         Write = 1 << 1,
+///         Write = bit_u32(1),
 ///
 ///         /// Execute permission.
-///         Execute = 1 << 2,
+///         Execute = bit_u32(2),
 ///     }
 /// );
 ///
diff --git a/rust/kernel/init.rs b/rust/kernel/init.rs
index 05a12e869a57..1fdc3963e3e3 100644
--- a/rust/kernel/init.rs
+++ b/rust/kernel/init.rs
@@ -158,7 +158,9 @@ pub trait InPlaceInit<T>: Sized {
     {
         // SAFETY: We delegate to `init` and only change the error type.
         let init = unsafe {
-            pin_init_from_closure(|slot| init.__pinned_init(slot).map_err(|e| Error::from(e)))
+            pin_init_from_closure(|slot| {
+                pin_init::raw_try_init(slot, init).map_err(|e| Error::from(e))
+            })
         };
         Self::try_pin_init(init, flags)
     }
@@ -176,7 +178,7 @@ pub trait InPlaceInit<T>: Sized {
     {
         // SAFETY: We delegate to `init` and only change the error type.
         let init = unsafe {
-            init_from_closure(|slot| init.__pinned_init(slot).map_err(|e| Error::from(e)))
+            init_from_closure(|slot| pin_init::raw_try_init(slot, init).map_err(|e| Error::from(e)))
         };
         Self::try_init(init, flags)
     }
diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs
index 9512af7156df..59144e1e3d36 100644
--- a/rust/kernel/lib.rs
+++ b/rust/kernel/lib.rs
@@ -94,6 +94,7 @@ pub mod list;
 pub mod maple_tree;
 pub mod miscdevice;
 pub mod mm;
+pub mod module;
 pub mod module_param;
 #[cfg(CONFIG_NET)]
 pub mod net;
@@ -140,77 +141,29 @@ pub mod xarray;
 #[doc(hidden)]
 pub use bindings;
 pub use macros;
+pub use module::{
+    InPlaceModule,
+    Module,
+    ModuleMetadata,
+    ThisModule, //
+};
 pub use uapi;
 
 /// Prefix to appear before log messages printed from within the `kernel` crate.
 const __LOG_PREFIX: &[u8] = b"rust_kernel\0";
 
-/// The top level entrypoint to implementing a kernel module.
-///
-/// For any teardown or cleanup operations, your type may implement [`Drop`].
-pub trait Module: Sized + Sync + Send {
-    /// Called at module initialization time.
-    ///
-    /// Use this method to perform whatever setup or registration your module
-    /// should do.
-    ///
-    /// Equivalent to the `module_init` macro in the C API.
-    fn init(module: &'static ThisModule) -> error::Result<Self>;
-}
-
-/// A module that is pinned and initialised in-place.
-pub trait InPlaceModule: Sync + Send {
-    /// Creates an initialiser for the module.
-    ///
-    /// It is called when the module is loaded.
-    fn init(module: &'static ThisModule) -> impl pin_init::PinInit<Self, error::Error>;
-}
-
-impl<T: Module> InPlaceModule for T {
-    fn init(module: &'static ThisModule) -> impl pin_init::PinInit<Self, error::Error> {
-        let initer = move |slot: *mut Self| {
-            let m = <Self as Module>::init(module)?;
+/// Dummy module type for `#[vtable]` `impl` blocks within the `kernel` crate (e.g. KUnit tests).
+// The `allow` is needed since it may be unused (e.g. KUnit tests may be disabled).
+#[allow(dead_code)]
+struct LocalModule;
 
-            // SAFETY: `slot` is valid for write per the contract with `pin_init_from_closure`.
-            unsafe { slot.write(m) };
-            Ok(())
-        };
+impl ModuleMetadata for LocalModule {
+    const NAME: &'static str::CStr = c"rust_kernel";
 
-        // SAFETY: On success, `initer` always fully initialises an instance of `Self`.
-        unsafe { pin_init::pin_init_from_closure(initer) }
-    }
-}
-
-/// Metadata attached to a [`Module`] or [`InPlaceModule`].
-pub trait ModuleMetadata {
-    /// The name of the module as specified in the `module!` macro.
-    const NAME: &'static crate::str::CStr;
-}
-
-/// Equivalent to `THIS_MODULE` in the C API.
-///
-/// C header: [`include/linux/init.h`](srctree/include/linux/init.h)
-pub struct ThisModule(*mut bindings::module);
-
-// SAFETY: `THIS_MODULE` may be used from all threads within a module.
-unsafe impl Sync for ThisModule {}
-
-impl ThisModule {
-    /// Creates a [`ThisModule`] given the `THIS_MODULE` pointer.
-    ///
-    /// # Safety
-    ///
-    /// The pointer must be equal to the right `THIS_MODULE`.
-    pub const unsafe fn from_ptr(ptr: *mut bindings::module) -> ThisModule {
-        ThisModule(ptr)
-    }
-
-    /// Access the raw pointer for this module.
-    ///
-    /// It is up to the user to use it correctly.
-    pub const fn as_ptr(&self) -> *mut bindings::module {
-        self.0
-    }
+    const THIS_MODULE: ThisModule = {
+        // SAFETY: `try_module_get`/`module_put` handle null module pointers gracefully.
+        unsafe { ThisModule::from_ptr(core::ptr::null_mut()) }
+    };
 }
 
 #[cfg(not(testlib))]
diff --git a/rust/kernel/miscdevice.rs b/rust/kernel/miscdevice.rs
index 83ce50def5ac..2a4329f98614 100644
--- a/rust/kernel/miscdevice.rs
+++ b/rust/kernel/miscdevice.rs
@@ -24,12 +24,13 @@ use crate::{
         IovIterSource, //
     },
     mm::virt::VmaNew,
+    module::this_module,
     prelude::*,
     seq_file::SeqFile,
     types::{
         ForeignOwnable,
         Opaque, //
-    },
+    }, //
 };
 use core::marker::PhantomData;
 
@@ -430,6 +431,7 @@ impl<T: MiscDevice> MiscdeviceVTable<T> {
         } else {
             None
         },
+        owner: this_module::<T::OwnerModule>().as_ptr(),
         ..pin_init::zeroed()
     };
 
diff --git a/rust/kernel/module.rs b/rust/kernel/module.rs
new file mode 100644
index 000000000000..d71370598447
--- /dev/null
+++ b/rust/kernel/module.rs
@@ -0,0 +1,80 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Module-related types and helpers.
+
+/// The entrypoint to implementing a kernel module.
+///
+/// For any teardown or cleanup operations, your type may implement [`Drop`].
+pub trait Module: Sized + Sync + Send {
+    /// Called at module initialization time.
+    ///
+    /// Use this method to perform whatever setup or registration your module
+    /// should do.
+    ///
+    /// Equivalent to the `module_init` macro in the C API.
+    fn init(module: &'static ThisModule) -> crate::error::Result<Self>;
+}
+
+/// A module that is pinned and initialised in-place.
+pub trait InPlaceModule: Sync + Send {
+    /// Creates an initialiser for the module.
+    ///
+    /// It is called when the module is loaded.
+    fn init(module: &'static ThisModule) -> impl pin_init::PinInit<Self, crate::error::Error>;
+}
+
+impl<T: Module> InPlaceModule for T {
+    fn init(module: &'static ThisModule) -> impl pin_init::PinInit<Self, crate::error::Error> {
+        let initer = move |slot: *mut Self| {
+            let m = <Self as Module>::init(module)?;
+
+            // SAFETY: `slot` is valid for write per the contract with `pin_init_from_closure`.
+            unsafe { slot.write(m) };
+            Ok(())
+        };
+
+        // SAFETY: On success, `initer` always fully initialises an instance of `Self`.
+        unsafe { pin_init::pin_init_from_closure(initer) }
+    }
+}
+
+/// Metadata attached to a [`Module`] or [`InPlaceModule`].
+pub trait ModuleMetadata {
+    /// The name of the module as specified in the `module!` macro.
+    const NAME: &'static crate::str::CStr;
+
+    /// The module's `THIS_MODULE` pointer.
+    const THIS_MODULE: ThisModule;
+}
+
+/// Returns a reference to the `THIS_MODULE` of the given module type.
+#[inline]
+pub const fn this_module<M: ModuleMetadata>() -> &'static ThisModule {
+    &M::THIS_MODULE
+}
+
+/// Equivalent to `THIS_MODULE` in the C API.
+///
+/// C header: [`include/linux/init.h`](srctree/include/linux/init.h)
+pub struct ThisModule(*mut crate::bindings::module);
+
+// SAFETY: `THIS_MODULE` may be used from all threads within a module.
+unsafe impl Sync for ThisModule {}
+
+impl ThisModule {
+    /// Creates a [`ThisModule`] given the `THIS_MODULE` pointer.
+    ///
+    /// # Safety
+    ///
+    /// The pointer must be equal to the right `THIS_MODULE`.
+    pub const unsafe fn from_ptr(ptr: *mut crate::bindings::module) -> ThisModule {
+        ThisModule(ptr)
+    }
+
+    /// Access the raw pointer for this module.
+    ///
+    /// It is up to the user to use it correctly.
+    pub const fn as_ptr(&self) -> *mut crate::bindings::module {
+        self.0
+    }
+}
diff --git a/rust/kernel/net/phy.rs b/rust/kernel/net/phy.rs
index 3ca99db5cccf..8b7036b8fe48 100644
--- a/rust/kernel/net/phy.rs
+++ b/rust/kernel/net/phy.rs
@@ -659,7 +659,11 @@ impl Registration {
         // the `drivers` slice are initialized properly. `drivers` will not be moved.
         // So it's just an FFI call.
         to_result(unsafe {
-            bindings::phy_drivers_register(drivers[0].0.get(), drivers.len().try_into()?, module.0)
+            bindings::phy_drivers_register(
+                drivers[0].0.get(),
+                drivers.len().try_into()?,
+                module.as_ptr(),
+            )
         })?;
         // INVARIANT: The `drivers` slice is successfully registered to the kernel via `phy_drivers_register`.
         Ok(Registration { drivers })
diff --git a/rust/kernel/num.rs b/rust/kernel/num.rs
index 8532b511384c..dbe848e30efe 100644
--- a/rust/kernel/num.rs
+++ b/rust/kernel/num.rs
@@ -5,6 +5,8 @@
 use core::ops;
 
 pub mod bounded;
+pub mod casts;
+
 pub use bounded::*;
 
 /// Designates unsigned primitive types.
diff --git a/rust/kernel/num/bounded.rs b/rust/kernel/num/bounded.rs
index dafe77782d79..d192610a687d 100644
--- a/rust/kernel/num/bounded.rs
+++ b/rust/kernel/num/bounded.rs
@@ -485,13 +485,45 @@ where
     /// assert_eq!(v_shifted.get(), 0xff);
     /// ```
     pub fn shr<const SHIFT: u32, const RES: u32>(self) -> Bounded<T, RES> {
-        const { assert!(RES + SHIFT >= N) }
+        const_assert!(SHIFT < T::BITS);
+        const_assert!(RES + SHIFT >= N);
 
         // SAFETY: We shift the value right by `SHIFT`, reducing the number of bits needed to
         // represent the shifted value by as much, and just asserted that `RES >= N - SHIFT`.
         unsafe { Bounded::__new(self.0 >> SHIFT) }
     }
 
+    /// Right-shifts `self` by `SHIFT` if that loses no set bits, and returns the result as a
+    /// `Bounded<_, RES>`, where `RES >= N - SHIFT`.
+    ///
+    /// Returns [`None`] if any of the `SHIFT` least significant bits of `self` is set.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use kernel::num::Bounded;
+    ///
+    /// let v = Bounded::<u32, 16>::new::<0xff00>();
+    /// let v_shifted: Option<Bounded<u32, 8>> = v.shr_exact::<8, _>();
+    ///
+    /// assert_eq!(v_shifted.map(|v| v.get()), Some(0xff));
+    ///
+    /// // A set bit would be shifted out.
+    /// let v = Bounded::<u32, 16>::new::<0xff01>();
+    /// let v_shifted: Option<Bounded<u32, 8>> = v.shr_exact::<8, _>();
+    ///
+    /// assert!(v_shifted.is_none());
+    /// ```
+    #[inline]
+    pub fn shr_exact<const SHIFT: u32, const RES: u32>(self) -> Option<Bounded<T, RES>> {
+        let shifted = self.shr::<SHIFT, RES>();
+        if shifted.get() << SHIFT == self.0 {
+            Some(shifted)
+        } else {
+            None
+        }
+    }
+
     /// Left-shifts `self` by `SHIFT` and returns the result as a `Bounded<_, RES>`, where `RES >=
     /// N + SHIFT`.
     ///
@@ -506,7 +538,7 @@ where
     /// assert_eq!(v_shifted.get(), 0xff00);
     /// ```
     pub fn shl<const SHIFT: u32, const RES: u32>(self) -> Bounded<T, RES> {
-        const { assert!(RES >= N + SHIFT) }
+        const_assert!(RES >= N + SHIFT);
 
         // SAFETY: We shift the value left by `SHIFT`, augmenting the number of bits needed to
         // represent the shifted value by as much, and just asserted that `RES >= N + SHIFT`.
diff --git a/rust/kernel/num/casts.rs b/rust/kernel/num/casts.rs
new file mode 100644
index 000000000000..7e6c7dec747d
--- /dev/null
+++ b/rust/kernel/num/casts.rs
@@ -0,0 +1,298 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Helpers for performing lossless integer casts.
+//!
+//! The `as` keyword can be used to perform casts between integer types, but it unfortunately makes
+//! no distinction between casts that are lossless, and casts from a larger type into a smaller one
+//! that might silently strip data away. Thus, its use in the kernel is discouraged in favor of
+//! [`From`] implementations.
+//!
+//! Conversely, there are casts that are lossless depending on the build architecture (such as
+//! casting [`usize`] to [`u64`] on 32 or 64 bit archs), but not supported by [`From`]
+//! implementations in the standard library because they are not portable. It does however make
+//! sense for the kernel to support these, if only for code that is architecture-specific.
+//!
+//! This module provides ways to perform such conversions safely:
+//!
+//! - A series of const functions (e.g. [`usize_as_u64`]) supporting safe conversions in const
+//!   context. Conversions supported by [`From`] implementations in the standard library are also
+//!   covered as the [`From`] trait cannot be used in const context.
+//! - Two extension traits, [`FromSafeCast`] and [`IntoSafeCast`], providing conversion methods
+//!   similar to [`From`] and [`Into`] for conversions that are safe to perform in the kernel, but
+//!   not supported by the standard library.
+//! - Another series of const functions (e.g. [`u64_into_u8`]) supporting the conversion of a const
+//!   value from a larger type into a smaller one, provided the value fits into the destination
+//!   type. This is useful if a constant is defined as a larger type, but needs to be used as a
+//!   smaller one.
+//! - An [`arch`] sub-module, defining more conversion functions that are only guaranteed to be
+//!   lossless for a given pointer size. These can only be used in code that is specific to a
+//!   given pointer size.
+//!
+//! # Examples
+//!
+//! ```
+//! use kernel::num::casts::{self, FromSafeCast, IntoSafeCast};
+//!
+//! // Conversion from const context.
+//! const USIZED_CONST: usize = casts::u8_as_usize(255u8);
+//!
+//! // Non-const conversions.
+//! let a = u64::from_safe_cast(4096usize);
+//! let b: u64 = 4096usize.into_safe_cast();
+//! ```
+
+use crate::prelude::*;
+
+/// Implements safe `as` conversion functions from a given type into a series of target types.
+///
+/// These functions can be used in place of `as`, with the guarantee that they will be lossless.
+macro_rules! impl_safe_as {
+    ($from:ty as { $($into:ty),* }) => {
+        $(
+        $crate::macros::paste! {
+            #[doc = ::core::concat!(
+                "Losslessly converts a [`",
+                ::core::stringify!($from),
+                "`] into a [`",
+                ::core::stringify!($into),
+                "`].")]
+            ///
+            /// This conversion is allowed as it is always lossless. Prefer this over the `as`
+            /// keyword to ensure no lossy casts are performed.
+            ///
+            /// This is for use from a `const` context. For non `const` use, prefer the
+            /// [`FromSafeCast`] and [`IntoSafeCast`] traits.
+            ///
+            /// # Examples
+            ///
+            /// ```
+            /// use kernel::num::casts;
+            ///
+            #[doc = ::core::concat!(
+                "assert_eq!(casts::",
+                ::core::stringify!($from),
+                "_as_",
+                ::core::stringify!($into),
+                "(1",
+                ::core::stringify!($from),
+                "), 1",
+                ::core::stringify!($into),
+                ");")]
+            /// ```
+            #[inline]
+            pub const fn [<$from _as_ $into>](value: $from) -> $into {
+                $crate::static_assert!(size_of::<$into>() >= size_of::<$from>());
+
+                value as $into
+            }
+        }
+        )*
+    };
+}
+
+// Valid `Into` transformations.
+impl_safe_as!(u8 as { u16, u32, u64, usize });
+impl_safe_as!(u16 as { u32, u64, usize });
+impl_safe_as!(u32 as { u64 });
+// A `usize` fits into a `u64` on all supported platforms.
+impl_safe_as!(usize as { u64 });
+// A `u32` fits into a `usize` on all supported platforms.
+impl_safe_as!(u32 as { usize });
+
+/// Extension trait providing guaranteed lossless cast to [`Self`] from `T`.
+///
+/// The standard library's [`From`] implementations do not cover conversions that are not portable
+/// or future-proof. For instance, even though it is safe today, [`From<usize>`] is not implemented
+/// for [`u64`] because of the possibility of needing to support larger-than-64bit architectures in
+/// the future.
+///
+/// The workaround is to either deal with the error handling of [`TryFrom`] for an operation that
+/// technically cannot fail, or to use the `as` keyword, which can silently strip data if the
+/// destination type is smaller than the source.
+///
+/// Both options are hardly acceptable for the kernel. It is also a much more architecture
+/// dependent environment, supporting only 32 and 64 bit architectures, with some modules
+/// explicitly depending on a specific bus width that could greatly benefit from infallible
+/// conversion operations.
+///
+/// Thus this extension trait that provides, for all architectures supported by the kernel,
+/// conversion methods between types for which such a cast is lossless.
+///
+/// In other words, this trait is implemented if, for all supported targets and with `t: T`, the
+/// `t as Self` operation is completely lossless.
+///
+/// Prefer this over the `as` keyword to guarantee that no lossy casts are performed.
+///
+/// If you need to perform a conversion in `const` context, use [`u32_as_usize`], [`usize_as_u64`],
+/// etc.
+///
+/// # Examples
+///
+/// ```
+/// use kernel::num::casts::FromSafeCast;
+///
+/// assert_eq!(usize::from_safe_cast(0xf00u32), 0xf00usize);
+/// ```
+pub trait FromSafeCast<T> {
+    /// Create a [`Self`] from `value`. This operation is guaranteed to be lossless.
+    fn from_safe_cast(value: T) -> Self;
+}
+
+// A `usize` fits into a `u64` on all supported platforms.
+impl FromSafeCast<usize> for u64 {
+    #[inline]
+    fn from_safe_cast(value: usize) -> Self {
+        usize_as_u64(value)
+    }
+}
+
+// A `u32` fits into a `usize` on all supported platforms.
+impl FromSafeCast<u32> for usize {
+    #[inline]
+    fn from_safe_cast(value: u32) -> Self {
+        u32_as_usize(value)
+    }
+}
+
+/// Counterpart to the [`FromSafeCast`] trait, i.e. this trait is to [`FromSafeCast`] what [`Into`]
+/// is to [`From`].
+///
+/// See the documentation of [`FromSafeCast`] for the motivation.
+///
+/// # Examples
+///
+/// ```
+/// use kernel::num::casts::IntoSafeCast;
+///
+/// assert_eq!(0xf00usize, 0xf00u32.into_safe_cast());
+/// ```
+pub trait IntoSafeCast<T> {
+    /// Convert `self` into a `T`. This operation is guaranteed to be lossless.
+    fn into_safe_cast(self) -> T;
+}
+
+/// Reverse operation for types implementing [`FromSafeCast`].
+impl<S, T> IntoSafeCast<T> for S
+where
+    T: FromSafeCast<S>,
+{
+    #[inline]
+    fn into_safe_cast(self) -> T {
+        T::from_safe_cast(self)
+    }
+}
+
+/// Implements lossless conversion of a constant from a larger type into a smaller one.
+macro_rules! impl_const_into {
+    ($from:ty => { $($into:ty),* }) => {
+        $(
+        $crate::macros::paste! {
+            #[doc = ::core::concat!(
+                "Performs a build-time safe conversion of a [`",
+                ::core::stringify!($from),
+                "`] constant value into a [`",
+                ::core::stringify!($into),
+                "`].")]
+            ///
+            /// This checks at compile-time that the conversion is lossless, and triggers a build
+            /// error if it isn't.
+            ///
+            /// # Examples
+            ///
+            /// ```
+            /// use kernel::num::casts;
+            ///
+            /// // Succeeds because the value of the source fits into the destination's type.
+            #[doc = ::core::concat!(
+                "assert_eq!(casts::",
+                ::core::stringify!($from),
+                "_into_",
+                ::core::stringify!($into),
+                "::<1",
+                ::core::stringify!($from),
+                ">(), 1",
+                ::core::stringify!($into),
+                ");")]
+            /// ```
+            #[inline]
+            pub const fn [<$from _into_ $into>]<const N: $from>() -> $into {
+                // Make sure that the target type is smaller than the source one.
+                $crate::static_assert!($from::BITS >= $into::BITS);
+                // CAST: we statically enforced above that `$from` is larger than `$into`, so the
+                // `as` conversion will be lossless.
+                $crate::const_assert!(N >= $into::MIN as $from && N <= $into::MAX as $from);
+
+                N as $into
+            }
+        }
+        )*
+    };
+}
+
+impl_const_into!(usize => { u8, u16, u32 });
+impl_const_into!(u64 => { u8, u16, u32 });
+impl_const_into!(u32 => { u8, u16 });
+impl_const_into!(u16 => { u8 });
+
+/// Conversions that are only lossless for the current architecture.
+///
+/// # Portability
+///
+/// Callers of this module become dependent on the setting of `CONFIG_64BIT`. Use with caution, and
+/// never in code that is portable across pointer sizes.
+pub mod arch {
+    /// Trait identical to [`FromSafeCast`](super::FromSafeCast), but for conversions that are not
+    /// available on all architectures.
+    pub trait FromSafeCastArch<T> {
+        /// Create a [`Self`] from `value`. This operation is guaranteed to be lossless.
+        fn from_safe_cast_arch(value: T) -> Self;
+    }
+
+    /// Trait identical to [`IntoSafeCast`](super::IntoSafeCast), but for conversions that are not
+    /// available on all architectures.
+    pub trait IntoSafeCastArch<T> {
+        /// Convert `self` into a `T`. This operation is guaranteed to be lossless.
+        fn into_safe_cast_arch(self) -> T;
+    }
+
+    /// Reverse operation for types implementing [`FromSafeCastArch`].
+    impl<S, T> IntoSafeCastArch<T> for S
+    where
+        T: FromSafeCastArch<S>,
+    {
+        #[inline]
+        fn into_safe_cast_arch(self) -> T {
+            T::from_safe_cast_arch(self)
+        }
+    }
+
+    /// A [`u64`] fits into a [`usize`] on 64-bit platforms.
+    #[cfg(CONFIG_64BIT)]
+    #[inline]
+    pub const fn u64_as_usize(value: u64) -> usize {
+        value as usize
+    }
+
+    #[cfg(CONFIG_64BIT)]
+    impl FromSafeCastArch<u64> for usize {
+        #[inline]
+        fn from_safe_cast_arch(value: u64) -> Self {
+            u64_as_usize(value)
+        }
+    }
+
+    /// A [`usize`] fits into a [`u32`] on 32-bit platforms.
+    #[cfg(not(CONFIG_64BIT))]
+    #[inline]
+    pub const fn usize_as_u32(value: usize) -> u32 {
+        value as u32
+    }
+
+    #[cfg(not(CONFIG_64BIT))]
+    impl FromSafeCastArch<usize> for u32 {
+        #[inline]
+        fn from_safe_cast_arch(value: usize) -> Self {
+            usize_as_u32(value)
+        }
+    }
+}
diff --git a/rust/kernel/pci.rs b/rust/kernel/pci.rs
index 5071cae6543f..4def9ca1824c 100644
--- a/rust/kernel/pci.rs
+++ b/rust/kernel/pci.rs
@@ -86,7 +86,7 @@ unsafe impl<T: Driver> driver::RegistrationOps for Adapter<T> {
 
         // SAFETY: `pdrv` is guaranteed to be a valid `DriverType`.
         to_result(unsafe {
-            bindings::__pci_register_driver(pdrv.get(), module.0, name.as_char_ptr())
+            bindings::__pci_register_driver(pdrv.get(), module.as_ptr(), name.as_char_ptr())
         })
     }
 
diff --git a/rust/kernel/platform.rs b/rust/kernel/platform.rs
index d41555a4b31d..5a5f4156d79b 100644
--- a/rust/kernel/platform.rs
+++ b/rust/kernel/platform.rs
@@ -83,7 +83,7 @@ unsafe impl<T: Driver> driver::RegistrationOps for Adapter<T> {
 
         // SAFETY: `pdrv` is guaranteed to be a valid `DriverType`.
         to_result(unsafe {
-            bindings::__platform_driver_register(pdrv.get(), module.0, name.as_char_ptr())
+            bindings::__platform_driver_register(pdrv.get(), module.as_ptr(), name.as_char_ptr())
         })
     }
 
diff --git a/rust/kernel/print.rs b/rust/kernel/print.rs
index 6fd84389a858..0d62beeedca5 100644
--- a/rust/kernel/print.rs
+++ b/rust/kernel/print.rs
@@ -99,7 +99,7 @@ pub mod format_strings {
 /// The format string must be one of the ones in [`format_strings`], and
 /// the module name must be null-terminated.
 ///
-/// [`_printk`]: srctree/include/linux/_printk.h
+/// [`_printk`]: srctree/include/linux/printk.h
 #[doc(hidden)]
 #[cfg_attr(not(CONFIG_PRINTK), allow(unused_variables))]
 pub unsafe fn call_printk(
diff --git a/rust/kernel/pwm.rs b/rust/kernel/pwm.rs
index 6c9d667009ef..8b3a580b4f0f 100644
--- a/rust/kernel/pwm.rs
+++ b/rust/kernel/pwm.rs
@@ -600,7 +600,7 @@ impl<T: PwmOps> Chip<T> {
         let drvdata_ptr = unsafe { bindings::pwmchip_get_drvdata(c_chip_ptr) };
 
         // SAFETY: We construct the `T` object in-place in the allocated private memory.
-        unsafe { data.__pinned_init(drvdata_ptr.cast()) }.inspect_err(|_| {
+        unsafe { pin_init::raw_try_init(drvdata_ptr.cast(), data) }.inspect_err(|_| {
             // SAFETY: It is safe to call `pwmchip_put()` with a valid pointer obtained
             // from `pwmchip_alloc()`. We will not use pointer after this.
             unsafe { bindings::pwmchip_put(c_chip_ptr) }
diff --git a/rust/kernel/sync/arc.rs b/rust/kernel/sync/arc.rs
index 5ac4961b7cd2..8ae0fe6f19ec 100644
--- a/rust/kernel/sync/arc.rs
+++ b/rust/kernel/sync/arc.rs
@@ -154,7 +154,7 @@ impl<T: ?Sized> ArcInner<T> {
     ///
     /// # Safety
     ///
-    /// `ptr` must have been returned by a previous call to [`Arc::into_raw`], and the `Arc` must
+    /// `ptr` must have been returned by a previous call to [`Arc::into_raw`], and the [`Arc`] must
     /// not yet have been destroyed.
     unsafe fn container_of(ptr: *const T) -> NonNull<ArcInner<T>> {
         let refcount_layout = Layout::new::<Refcount>();
@@ -253,7 +253,7 @@ impl<T: ?Sized> Arc<T> {
 
     /// Convert the [`Arc`] into a raw pointer.
     ///
-    /// The raw pointer has ownership of the refcount that this Arc object owned.
+    /// The raw pointer has ownership of the refcount that this [`Arc`] object owned.
     pub fn into_raw(self) -> *const T {
         let ptr = self.ptr.as_ptr();
         core::mem::forget(self);
@@ -261,7 +261,7 @@ impl<T: ?Sized> Arc<T> {
         unsafe { core::ptr::addr_of!((*ptr).data) }
     }
 
-    /// Return a raw pointer to the data in this arc.
+    /// Return a raw pointer to the data in this [`Arc`].
     pub fn as_ptr(this: &Self) -> *const T {
         let ptr = this.ptr.as_ptr();
 
@@ -305,7 +305,7 @@ impl<T: ?Sized> Arc<T> {
 
     /// Converts this [`Arc`] into a [`UniqueArc`], or destroys it if it is not unique.
     ///
-    /// When this destroys the `Arc`, it does so while properly avoiding races. This means that
+    /// When this destroys the [`Arc`], it does so while properly avoiding races. This means that
     /// this method will never call the destructor of the value.
     ///
     /// # Examples
@@ -345,11 +345,11 @@ impl<T: ?Sized> Arc<T> {
 
         // If the refcount reaches a non-zero value, then we have destroyed this `Arc` and will
         // return without further touching the `Arc`. If the refcount reaches zero, then there are
-        // no other arcs, and we can create a `UniqueArc`.
+        // no other `Arc`s, and we can create a `UniqueArc`.
         if refcount.dec_and_test() {
             refcount.set(1);
 
-            // INVARIANT: We own the only refcount to this arc, so we may create a `UniqueArc`. We
+            // INVARIANT: We own the only refcount to this `Arc`, so we may create a `UniqueArc`. We
             // must pin the `UniqueArc` because the values was previously in an `Arc`, and they pin
             // their values.
             Some(Pin::from(UniqueArc {
@@ -717,7 +717,7 @@ impl<T> InPlaceWrite<T> for UniqueArc<MaybeUninit<T>> {
         let slot = self.as_mut_ptr();
         // SAFETY: When init errors/panics, slot will get deallocated but not dropped,
         // slot is valid.
-        unsafe { init.__init(slot)? };
+        unsafe { pin_init::raw_try_init(slot, init)? };
         // SAFETY: All fields have been initialized.
         Ok(unsafe { self.assume_init() })
     }
@@ -727,7 +727,7 @@ impl<T> InPlaceWrite<T> for UniqueArc<MaybeUninit<T>> {
         let slot = self.as_mut_ptr();
         // SAFETY: When init errors/panics, slot will get deallocated but not dropped,
         // slot is valid and will not be moved, because we pin it later.
-        unsafe { init.__pinned_init(slot)? };
+        unsafe { pin_init::raw_try_init(slot, init)? };
         // SAFETY: All fields have been initialized.
         Ok(unsafe { self.assume_init() }.into())
     }
@@ -795,7 +795,7 @@ impl<T> UniqueArc<MaybeUninit<T>> {
     #[inline]
     pub fn init_with<E>(mut self, init: impl Init<T, E>) -> core::result::Result<UniqueArc<T>, E> {
         // SAFETY: The supplied pointer is valid for initialization.
-        match unsafe { init.__init(self.as_mut_ptr()) } {
+        match unsafe { pin_init::raw_try_init(self.as_mut_ptr(), init) } {
             // SAFETY: Initialization completed successfully.
             Ok(()) => Ok(unsafe { self.assume_init() }),
             Err(err) => Err(err),
@@ -810,7 +810,7 @@ impl<T> UniqueArc<MaybeUninit<T>> {
     ) -> core::result::Result<Pin<UniqueArc<T>>, E> {
         // SAFETY: The supplied pointer is valid for initialization and we will later pin the value
         // to ensure it does not move.
-        match unsafe { init.__pinned_init(self.as_mut_ptr()) } {
+        match unsafe { pin_init::raw_try_init(self.as_mut_ptr(), init) } {
             // SAFETY: Initialization completed successfully.
             Ok(()) => Ok(unsafe { self.assume_init() }.into()),
             Err(err) => Err(err),
diff --git a/rust/kernel/sync/aref.rs b/rust/kernel/sync/aref.rs
index b721b2e00b98..9983ee085248 100644
--- a/rust/kernel/sync/aref.rs
+++ b/rust/kernel/sync/aref.rs
@@ -24,6 +24,11 @@ use core::{
     ptr::NonNull, //
 };
 
+use crate::{
+    prelude::*,
+    types::ForeignOwnable, //
+};
+
 /// Types that are _always_ reference counted.
 ///
 /// It allows such types to define their own custom ref increment and decrement functions.
@@ -188,6 +193,51 @@ where
 }
 impl<T: AlwaysRefCounted + Eq> Eq for ARef<T> {}
 
+// SAFETY: `into_foreign` returns a pointer from `NonNull::as_ptr`, so it's non-null. The
+// `ARef` invariant guarantees that `ptr` points to a valid `T`, so it's aligned to `T`.
+unsafe impl<T: AlwaysRefCounted> ForeignOwnable for ARef<T> {
+    const FOREIGN_ALIGN: usize = core::mem::align_of::<T>();
+
+    type Borrowed<'a>
+        = &'a T
+    where
+        Self: 'a;
+    type BorrowedMut<'a>
+        = &'a T
+    where
+        Self: 'a;
+
+    #[inline]
+    fn into_foreign(self) -> *mut c_void {
+        ARef::into_raw(self).as_ptr().cast()
+    }
+
+    #[inline]
+    unsafe fn from_foreign(ptr: *mut c_void) -> Self {
+        // SAFETY: The safety requirements of this function ensure that `ptr` comes from a previous
+        // call to `Self::into_foreign`.
+        let ptr = unsafe { NonNull::new_unchecked(ptr.cast()) };
+
+        // SAFETY: `ptr` came from `into_foreign`, which consumed an `ARef` without decrementing
+        // the refcount, so we can transfer the ownership to the new `ARef`.
+        unsafe { ARef::from_raw(ptr) }
+    }
+
+    #[inline]
+    unsafe fn borrow<'a>(ptr: *mut c_void) -> &'a T {
+        // SAFETY: The safety requirements of this method ensure that the object remains alive and
+        // immutable for the duration of 'a.
+        unsafe { &*ptr.cast() }
+    }
+
+    #[inline]
+    unsafe fn borrow_mut<'a>(ptr: *mut c_void) -> &'a T {
+        // SAFETY: The safety requirements for `borrow_mut` are a superset of the safety
+        // requirements for `borrow`.
+        unsafe { <Self as ForeignOwnable>::borrow(ptr) }
+    }
+}
+
 impl<T, U> PartialEq<&'_ U> for ARef<T>
 where
     T: AlwaysRefCounted + PartialEq<U>,
diff --git a/rust/kernel/sync/rcu.rs b/rust/kernel/sync/rcu.rs
index a32bef6e490b..42d1b26a2143 100644
--- a/rust/kernel/sync/rcu.rs
+++ b/rust/kernel/sync/rcu.rs
@@ -50,3 +50,23 @@ impl Drop for Guard {
 pub fn read_lock() -> Guard {
     Guard::new()
 }
+
+/// Wait until all in-flight `call_rcu()` callbacks complete.
+///
+/// Note that this primitive does not necessarily wait for an RCU grace period
+/// to complete. For example, if there are no RCU callbacks queued anywhere
+/// in the system, then [`rcu_barrier()`] is within its rights to return
+/// immediately, without waiting for anything, much less an RCU grace period.
+/// In fact, [`rcu_barrier()`] will normally not result in any RCU grace periods
+/// beyond those that were already destined to be executed.
+///
+/// In kernels built with `CONFIG_RCU_LAZY=y`, this function also hurries all
+/// pending lazy RCU callbacks.
+///
+/// Note that this is one of the RCU primitives which must not be called in
+/// atomic context.
+#[inline]
+pub fn rcu_barrier() {
+    // SAFETY: `rcu_barrier()` is always safe to be called. It just might wait for a grace period.
+    unsafe { bindings::rcu_barrier() };
+}
diff --git a/rust/kernel/time.rs b/rust/kernel/time.rs
index b8463823aed9..6c0a5e8090d0 100644
--- a/rust/kernel/time.rs
+++ b/rust/kernel/time.rs
@@ -246,7 +246,7 @@ impl<C: ClockSource> ops::Sub for Instant<C> {
     #[inline]
     fn sub(self, other: Instant<C>) -> Delta {
         Delta {
-            nanos: self.inner - other.inner,
+            value: self.inner - other.inner,
         }
     }
 }
@@ -258,7 +258,7 @@ impl<T: ClockSource> ops::Add<Delta> for Instant<T> {
     fn add(self, rhs: Delta) -> Self::Output {
         // INVARIANT: With arithmetic over/underflow checks enabled, this will panic if we overflow
         // (e.g. go above `KTIME_MAX`)
-        let res = self.inner + rhs.nanos;
+        let res = self.inner + rhs.value;
 
         // INVARIANT: With overflow checks enabled, we verify here that the value is >= 0
         #[cfg(CONFIG_RUST_OVERFLOW_CHECKS)]
@@ -278,7 +278,7 @@ impl<T: ClockSource> ops::Sub<Delta> for Instant<T> {
     fn sub(self, rhs: Delta) -> Self::Output {
         // INVARIANT: With arithmetic over/underflow checks enabled, this will panic if we overflow
         // (e.g. go above `KTIME_MAX`)
-        let res = self.inner - rhs.nanos;
+        let res = self.inner - rhs.value;
 
         // INVARIANT: With overflow checks enabled, we verify here that the value is >= 0
         #[cfg(CONFIG_RUST_OVERFLOW_CHECKS)]
@@ -291,14 +291,64 @@ impl<T: ClockSource> ops::Sub<Delta> for Instant<T> {
     }
 }
 
+mod private {
+    pub trait Sealed {}
+
+    impl Sealed for super::Nsec {}
+    impl Sealed for super::Jiffy {}
+}
+
+/// A trait for time units.
+pub trait TimeUnit: private::Sealed {
+    /// The underlying representation of the time unit.
+    type Repr: Copy + Clone + PartialEq + PartialOrd + Eq + Ord + core::fmt::Debug;
+}
+
+/// A time unit of nanoseconds.
+///
+/// A [`Delta<Nsec>`] stores its value as [`i64`] nanoseconds and can represent
+/// any [`i64`] value, including negative, zero, and positive numbers.
+#[derive(Copy, Clone, PartialEq, PartialOrd, Eq, Ord, Debug)]
+pub enum Nsec {}
+
+impl TimeUnit for Nsec {
+    type Repr = i64;
+}
+
+/// A time unit of jiffies.
+///
+/// A [`Delta<Jiffy>`] stores its value as [`isize`] jiffies and can represent
+/// any [`isize`] value, including negative, zero, and positive numbers.
+#[derive(Copy, Clone, PartialEq, PartialOrd, Eq, Ord, Debug)]
+pub enum Jiffy {}
+
+impl TimeUnit for Jiffy {
+    type Repr = isize;
+}
+
 /// A span of time.
 ///
-/// This struct represents a span of time, with its value stored as nanoseconds.
-/// The value can represent any valid i64 value, including negative, zero, and
-/// positive numbers.
+/// The span is stored in the unit given by the type parameter `U` (see
+/// [`TimeUnit`]); its value has type `U::Repr`. `U` defaults to [`Nsec`], so a
+/// plain [`Delta`] is a span in nanoseconds. The value can be negative, zero, or
+/// positive.
 #[derive(Copy, Clone, PartialEq, PartialOrd, Eq, Ord, Debug)]
-pub struct Delta {
-    nanos: i64,
+pub struct Delta<U: TimeUnit = Nsec> {
+    value: U::Repr,
+}
+
+impl Delta<Jiffy> {
+    /// Create a new [`Delta`] from a number of jiffies.
+    #[inline]
+    pub const fn from_jiffies(jiffies: isize) -> Self {
+        Self { value: jiffies }
+    }
+
+    /// Return the number of jiffies in the [`Delta`].
+    #[inline]
+    pub const fn as_jiffies(self) -> isize {
+        self.value
+    }
 }
 
 impl ops::Add for Delta {
@@ -307,7 +357,7 @@ impl ops::Add for Delta {
     #[inline]
     fn add(self, rhs: Self) -> Self {
         Self {
-            nanos: self.nanos + rhs.nanos,
+            value: self.value + rhs.value,
         }
     }
 }
@@ -315,7 +365,7 @@ impl ops::Add for Delta {
 impl ops::AddAssign for Delta {
     #[inline]
     fn add_assign(&mut self, rhs: Self) {
-        self.nanos += rhs.nanos;
+        self.value += rhs.value;
     }
 }
 
@@ -325,7 +375,7 @@ impl ops::Sub for Delta {
     #[inline]
     fn sub(self, rhs: Self) -> Self::Output {
         Self {
-            nanos: self.nanos - rhs.nanos,
+            value: self.value - rhs.value,
         }
     }
 }
@@ -333,7 +383,7 @@ impl ops::Sub for Delta {
 impl ops::SubAssign for Delta {
     #[inline]
     fn sub_assign(&mut self, rhs: Self) {
-        self.nanos -= rhs.nanos;
+        self.value -= rhs.value;
     }
 }
 
@@ -343,7 +393,7 @@ impl ops::Mul<i64> for Delta {
     #[inline]
     fn mul(self, rhs: i64) -> Self::Output {
         Self {
-            nanos: self.nanos * rhs,
+            value: self.value * rhs,
         }
     }
 }
@@ -351,7 +401,7 @@ impl ops::Mul<i64> for Delta {
 impl ops::MulAssign<i64> for Delta {
     #[inline]
     fn mul_assign(&mut self, rhs: i64) {
-        self.nanos *= rhs;
+        self.value *= rhs;
     }
 }
 
@@ -362,25 +412,25 @@ impl ops::Div for Delta {
     fn div(self, rhs: Self) -> Self::Output {
         #[cfg(CONFIG_64BIT)]
         {
-            self.nanos / rhs.nanos
+            self.value / rhs.value
         }
 
         #[cfg(not(CONFIG_64BIT))]
         {
             // SAFETY: This function is always safe to call regardless of the input values
-            unsafe { bindings::div64_s64(self.nanos, rhs.nanos) }
+            unsafe { bindings::div64_s64(self.value, rhs.value) }
         }
     }
 }
 
 impl Delta {
     /// A span of time equal to zero.
-    pub const ZERO: Self = Self { nanos: 0 };
+    pub const ZERO: Self = Self { value: 0 };
 
     /// Create a new [`Delta`] from a number of nanoseconds.
     #[inline]
     pub const fn from_nanos(nanos: i64) -> Self {
-        Self { nanos }
+        Self { value: nanos }
     }
 
     /// Create a new [`Delta`] from a number of microseconds.
@@ -391,7 +441,7 @@ impl Delta {
     #[inline]
     pub const fn from_micros(micros: i64) -> Self {
         Self {
-            nanos: micros.saturating_mul(NSEC_PER_USEC),
+            value: micros.saturating_mul(NSEC_PER_USEC),
         }
     }
 
@@ -403,7 +453,7 @@ impl Delta {
     #[inline]
     pub const fn from_millis(millis: i64) -> Self {
         Self {
-            nanos: millis.saturating_mul(NSEC_PER_MSEC),
+            value: millis.saturating_mul(NSEC_PER_MSEC),
         }
     }
 
@@ -415,7 +465,7 @@ impl Delta {
     #[inline]
     pub const fn from_secs(secs: i64) -> Self {
         Self {
-            nanos: secs.saturating_mul(NSEC_PER_SEC),
+            value: secs.saturating_mul(NSEC_PER_SEC),
         }
     }
 
@@ -434,29 +484,32 @@ impl Delta {
     /// Return the number of nanoseconds in the [`Delta`].
     #[inline]
     pub const fn as_nanos(self) -> i64 {
-        self.nanos
+        self.value
     }
 
     /// Return the smallest number of microseconds greater than or equal
     /// to the value in the [`Delta`].
     #[inline]
     pub fn as_micros_ceil(self) -> i64 {
+        // Only positive values need to be rounded up: truncating division already
+        // rounds towards zero, i.e. up, for negative values.
+        //
+        // The usual `(nanos + d - 1) / d` is not used because the addition overflows
+        // once `nanos` exceeds `i64::MAX - (d - 1)`; saturating the addition instead
+        // would drop the rounding bias and return a result one unit too small.
         let n = self.as_nanos();
-        let n = if n >= 0 {
-            n.saturating_add(NSEC_PER_USEC - 1)
-        } else {
-            n
-        };
+
+        let (n, add) = if n > 0 { (n - 1, 1) } else { (n, 0) };
 
         #[cfg(CONFIG_64BIT)]
         {
-            n / NSEC_PER_USEC
+            n / NSEC_PER_USEC + add
         }
 
         #[cfg(not(CONFIG_64BIT))]
         // SAFETY: It is always safe to call `ktime_to_us()` with any value.
         unsafe {
-            bindings::ktime_to_us(n)
+            bindings::ktime_to_us(n) + add
         }
     }
 
@@ -475,6 +528,32 @@ impl Delta {
         }
     }
 
+    /// Return the smallest number of milliseconds greater than or equal
+    /// to the value in the [`Delta`].
+    #[inline]
+    pub fn as_millis_ceil(self) -> i64 {
+        // Only positive values need to be rounded up: truncating division already
+        // rounds towards zero, i.e. up, for negative values.
+        //
+        // The usual `(nanos + d - 1) / d` is not used because the addition overflows
+        // once `nanos` exceeds `i64::MAX - (d - 1)`; saturating the addition instead
+        // would drop the rounding bias and return a result one unit too small.
+        let n = self.as_nanos();
+
+        let (n, add) = if n > 0 { (n - 1, 1) } else { (n, 0) };
+
+        #[cfg(CONFIG_64BIT)]
+        {
+            n / NSEC_PER_MSEC + add
+        }
+
+        #[cfg(not(CONFIG_64BIT))]
+        // SAFETY: It is always safe to call `ktime_to_ms()` with any value.
+        unsafe {
+            bindings::ktime_to_ms(n) + add
+        }
+    }
+
     /// Return `self % dividend` where `dividend` is in nanoseconds.
     ///
     /// The kernel doesn't have any emulation for `s64 % s64` on 32 bit platforms, so this is
@@ -484,7 +563,7 @@ impl Delta {
         #[cfg(CONFIG_64BIT)]
         {
             Self {
-                nanos: self.as_nanos() % i64::from(dividend),
+                value: self.as_nanos() % i64::from(dividend),
             }
         }
 
@@ -496,7 +575,7 @@ impl Delta {
             unsafe { bindings::div_s64_rem(self.as_nanos(), dividend, &mut rem) };
 
             Self {
-                nanos: i64::from(rem),
+                value: i64::from(rem),
             }
         }
     }
diff --git a/rust/kernel/types.rs b/rust/kernel/types.rs
index ac316fd7b538..67b3874cb3d2 100644
--- a/rust/kernel/types.rs
+++ b/rust/kernel/types.rs
@@ -417,13 +417,13 @@ impl<T> Opaque<T> {
 
 impl<T> Wrapper<T> for Opaque<T> {
     /// Create an opaque pin-initializer from the given pin-initializer.
-    fn pin_init<E>(slot: impl PinInit<T, E>) -> impl PinInit<Self, E> {
-        Self::try_ffi_init(|ptr: *mut T| {
+    fn pin_init<E>(init: impl PinInit<T, E>) -> impl PinInit<Self, E> {
+        Self::try_ffi_init(|slot: *mut T| {
             // SAFETY:
-            //   - `ptr` is a valid pointer to uninitialized memory,
+            //   - `slot` is a valid pointer to uninitialized memory,
             //   - `slot` is not accessed on error,
             //   - `slot` is pinned in memory.
-            unsafe { PinInit::<T, E>::__pinned_init(slot, ptr) }
+            unsafe { pin_init::raw_try_init(slot, init) }
         })
     }
 }
diff --git a/rust/kernel/usb.rs b/rust/kernel/usb.rs
index 7aff0c82d0af..870423806e4f 100644
--- a/rust/kernel/usb.rs
+++ b/rust/kernel/usb.rs
@@ -63,7 +63,7 @@ unsafe impl<T: Driver> driver::RegistrationOps for Adapter<T> {
 
         // SAFETY: `udrv` is guaranteed to be a valid `DriverType`.
         to_result(unsafe {
-            bindings::usb_register_driver(udrv.get(), module.0, name.as_char_ptr())
+            bindings::usb_register_driver(udrv.get(), module.as_ptr(), name.as_char_ptr())
         })
     }