Merge tag 'driver-core-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core

Pull driver core updates from Danilo Krummrich:
 "Arch Topology:
   - Move parse_acpi_topology() from arm64 to common code for reuse in
     RISC-V

  CPU:
   - Expose housekeeping CPUs through /sys/devices/system/cpu/housekeeping
   - Print a newline (or 0x0A) instead of '(null)' reading
     /sys/devices/system/cpu/nohz_full when nohz_full= is not set

  debugfs
   - Remove (broken) 'no-mount' mode
   - Remove redundant access mode checks in debugfs_get_tree() and
     debugfs_create_*() functions

  Devres:
   - Remove unused devm_free_percpu() helper
   - Move devm_alloc_percpu() from device.h to devres.h

  Firmware Loader:
   - Replace simple_strtol() with kstrtoint()
   - Do not call cancel_store() when no upload is in progress

  kernfs:
   - Increase struct super_block::maxbytes to MAX_LFS_FILESIZE
   - Fix a missing unwind path in __kernfs_new_node()

  Misc:
   - Increase the name size in struct auxiliary_device_id to 40
     characters
   - Replace system_unbound_wq with system_dfl_wq and add WQ_PERCPU to
     alloc_workqueue()

  Platform:
   - Replace ERR_PTR() with IOMEM_ERR_PTR() in platform ioremap
     functions

  Rust:
   - Auxiliary:
      - Unregister auxiliary device on parent device unbind
      - Move parent() to impl Device; implement device context aware
        parent() for Device<Bound>
      - Illustrate how to safely obtain a driver's device private data
        when calling from an auxiliary driver into the parant device
        driver

   - DebugFs:
      - Implement support for binary large objects

   - Device:
      - Let probe() return the driver's device private data as pinned
        initializer, i.e. impl PinInit<Self, Error>
      - Implement safe accessor for a driver's device private data for
        Device<Bound> (returned reference can't out-live driver binding
        and guarantees the correct private data type)
      - Implement AsBusDevice trait, to be used by class device
        abstractions to derive the bus device type of the parent device

   - DMA:
      - Store raw pointer of allocation as NonNull
      - Use start_ptr() and start_ptr_mut() to inherit correct
        mutability of self

   - FS:
      - Add file::Offset type alias

   - I2C:
      - Add abstractions for I2C device / driver infrastructure
      - Implement abstractions for manual I2C device registrations

   - I/O:
      - Use "kernel vertical" style for imports
      - Define ResourceSize as resource_size_t
      - Move ResourceSize to top-level I/O module
      - Add type alias for phys_addr_t
      - Implement Rust version of read_poll_timeout_atomic()

   - PCI:
      - Use "kernel vertical" style for imports
      - Move I/O and IRQ infrastructure to separate files
      - Add support for PCI interrupt vectors
      - Implement TryInto<IrqRequest<'a>> for IrqVector<'a> to convert
        an IrqVector bound to specific pci::Device into an IrqRequest
        bound to the same pci::Device's parent Device
      - Leverage pin_init_scope() to get rid of redundant Result in IRQ
        methods

   - PinInit:
      - Add {pin_}init_scope() to execute code before creating an
        initializer

   - Platform:
      - Leverage pin_init_scope() to get rid of redundant Result in IRQ
        methods

   - Timekeeping:
      - Implement abstraction of udelay()

   - Uaccess:
      - Implement read_slice_partial() and read_slice_file() for
        UserSliceReader
      - Implement write_slice_partial() and write_slice_file() for
        UserSliceWriter

  sysfs:
   - Prepare the constification of struct attribute"

* tag 'driver-core-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (75 commits)
  rust: pci: fix build failure when CONFIG_PCI_MSI is disabled
  debugfs: Fix default access mode config check
  debugfs: Remove broken no-mount mode
  debugfs: Remove redundant access mode checks
  driver core: Check drivers_autoprobe for all added devices
  driver core: WQ_PERCPU added to alloc_workqueue users
  driver core: replace use of system_unbound_wq with system_dfl_wq
  tick/nohz: Expose housekeeping CPUs in sysfs
  tick/nohz: avoid showing '(null)' if nohz_full= not set
  sysfs/cpu: Use DEVICE_ATTR_RO for nohz_full attribute
  kernfs: fix memory leak of kernfs_iattrs in __kernfs_new_node
  fs/kernfs: raise sb->maxbytes to MAX_LFS_FILESIZE
  mod_devicetable: Bump auxiliary_device_id name size
  sysfs: simplify attribute definition macros
  samples/kobject: constify 'struct foo_attribute'
  samples/kobject: add is_visible() callback to attribute group
  sysfs: attribute_group: enable const variants of is_visible()
  sysfs: introduce __SYSFS_FUNCTION_ALTERNATIVE()
  sysfs: transparently handle const pointers in ATTRIBUTE_GROUPS()
  sysfs: attribute_group: allow registration of const attribute
  ...

1 files changed, 16 insertions, 13 deletions

diff --git a/rust/kernel/dma.rs b/rust/kernel/dma.rs
index 4e0af3e1a3b9..84d3c67269e8 100644
--- a/rust/kernel/dma.rs
+++ b/rust/kernel/dma.rs
@@ -12,6 +12,7 @@ use crate::{
     sync::aref::ARef,
     transmute::{AsBytes, FromBytes},
 };
+use core::ptr::NonNull;
 
 /// DMA address type.
 ///
@@ -358,7 +359,7 @@ pub struct CoherentAllocation<T: AsBytes + FromBytes> {
     dev: ARef<device::Device>,
     dma_handle: DmaAddress,
     count: usize,
-    cpu_addr: *mut T,
+    cpu_addr: NonNull<T>,
     dma_attrs: Attrs,
 }
 
@@ -392,7 +393,7 @@ impl<T: AsBytes + FromBytes> CoherentAllocation<T> {
             .ok_or(EOVERFLOW)?;
         let mut dma_handle = 0;
         // SAFETY: Device pointer is guaranteed as valid by the type invariant on `Device`.
-        let ret = unsafe {
+        let addr = unsafe {
             bindings::dma_alloc_attrs(
                 dev.as_raw(),
                 size,
@@ -401,9 +402,7 @@ impl<T: AsBytes + FromBytes> CoherentAllocation<T> {
                 dma_attrs.as_raw(),
             )
         };
-        if ret.is_null() {
-            return Err(ENOMEM);
-        }
+        let addr = NonNull::new(addr).ok_or(ENOMEM)?;
         // INVARIANT:
         // - We just successfully allocated a coherent region which is accessible for
         //   `count` elements, hence the cpu address is valid. We also hold a refcounted reference
@@ -414,7 +413,7 @@ impl<T: AsBytes + FromBytes> CoherentAllocation<T> {
             dev: dev.into(),
             dma_handle,
             count,
-            cpu_addr: ret.cast::<T>(),
+            cpu_addr: addr.cast(),
             dma_attrs,
         })
     }
@@ -446,13 +445,13 @@ impl<T: AsBytes + FromBytes> CoherentAllocation<T> {
 
     /// Returns the base address to the allocated region in the CPU's virtual address space.
     pub fn start_ptr(&self) -> *const T {
-        self.cpu_addr
+        self.cpu_addr.as_ptr()
     }
 
     /// Returns the base address to the allocated region in the CPU's virtual address space as
     /// a mutable pointer.
     pub fn start_ptr_mut(&mut self) -> *mut T {
-        self.cpu_addr
+        self.cpu_addr.as_ptr()
     }
 
     /// Returns a DMA handle which may be given to the device as the DMA address base of
@@ -505,7 +504,7 @@ impl<T: AsBytes + FromBytes> CoherentAllocation<T> {
         //   data is also guaranteed by the safety requirements of the function.
         // - `offset + count` can't overflow since it is smaller than `self.count` and we've checked
         //   that `self.count` won't overflow early in the constructor.
-        Ok(unsafe { core::slice::from_raw_parts(self.cpu_addr.add(offset), count) })
+        Ok(unsafe { core::slice::from_raw_parts(self.start_ptr().add(offset), count) })
     }
 
     /// Performs the same functionality as [`CoherentAllocation::as_slice`], except that a mutable
@@ -525,7 +524,7 @@ impl<T: AsBytes + FromBytes> CoherentAllocation<T> {
         //   data is also guaranteed by the safety requirements of the function.
         // - `offset + count` can't overflow since it is smaller than `self.count` and we've checked
         //   that `self.count` won't overflow early in the constructor.
-        Ok(unsafe { core::slice::from_raw_parts_mut(self.cpu_addr.add(offset), count) })
+        Ok(unsafe { core::slice::from_raw_parts_mut(self.start_ptr_mut().add(offset), count) })
     }
 
     /// Writes data to the region starting from `offset`. `offset` is in units of `T`, not the
@@ -557,7 +556,11 @@ impl<T: AsBytes + FromBytes> CoherentAllocation<T> {
         // - `offset + count` can't overflow since it is smaller than `self.count` and we've checked
         //   that `self.count` won't overflow early in the constructor.
         unsafe {
-            core::ptr::copy_nonoverlapping(src.as_ptr(), self.cpu_addr.add(offset), src.len())
+            core::ptr::copy_nonoverlapping(
+                src.as_ptr(),
+                self.start_ptr_mut().add(offset),
+                src.len(),
+            )
         };
         Ok(())
     }
@@ -576,7 +579,7 @@ impl<T: AsBytes + FromBytes> CoherentAllocation<T> {
         // and we've just checked that the range and index is within bounds.
         // - `offset` can't overflow since it is smaller than `self.count` and we've checked
         // that `self.count` won't overflow early in the constructor.
-        Ok(unsafe { self.cpu_addr.add(offset) })
+        Ok(unsafe { self.cpu_addr.as_ptr().add(offset) })
     }
 
     /// Reads the value of `field` and ensures that its type is [`FromBytes`].
@@ -637,7 +640,7 @@ impl<T: AsBytes + FromBytes> Drop for CoherentAllocation<T> {
             bindings::dma_free_attrs(
                 self.dev.as_raw(),
                 size,
-                self.cpu_addr.cast(),
+                self.start_ptr_mut().cast(),
                 self.dma_handle,
                 self.dma_attrs.as_raw(),
             )