Merge tag 'drm-rust-next-2025-09-16' of https://gitlab.freedesktop.org/drm/rust/kernel into drm-next

DRM Rust changes for v6.18

Alloc
  - Add BorrowedPage type and AsPageIter trait
  - Implement Vmalloc::to_page() and VmallocPageIter
  - Implement AsPageIter for VBox and VVec

DMA & Scatterlist
  - Add dma::DataDirection and type alias for dma_addr_t
  - Abstraction for struct scatterlist and struct sg_table

DRM
  - In the DRM GEM module, simplify overall use of generics, add
    DriverFile type alias and drop Object::SIZE.

Nova (Core)
  - Various register!() macro improvements (paving the way for lifting
    it to common driver infrastructure)
  - Minor VBios fixes and refactoring
  - Minor firmware request refactoring
  - Advance firmware boot stages; process Booter and patch its
    signature, process GSP and GSP bootloader
  - Switch development fimrware version to r570.144
  - Add basic firmware bindings for r570.144
  - Move GSP boot code to its own module
  - Clean up and take advantage of pin-init features to store most of
    the driver's private data within a single allocation
  - Update ARef import from sync::aref
  - Add website to MAINTAINERS entry

Nova (DRM)
  - Update ARef import from sync::aref
  - Add website to MAINTAINERS entry

Pin-Init
  - Merge pin-init PR from Benno
    - `#[pin_data]` now generates a `*Projection` struct similar to the
      `pin-project` crate.

    - Add initializer code blocks to `[try_][pin_]init!` macros: make
      initializer macros accept any number of `_: {/* arbitrary code
      */},` & make them run the code at that point.

    - Make the `[try_][pin_]init!` macros expose initialized fields via
      a `let` binding as `&mut T` or `Pin<&mut T>` for later fields.

Rust
  - Various methods for AsBytes and FromBytes traits

Tyr
  - Initial Rust driver skeleton for ARM Mali GPUs.
    - It can power up the GPU, query for GPU metatdata through MMIO and
      provide the metadata to userspace via DRM device IOCTL (struct
      drm_panthor_dev_query).

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: "Danilo Krummrich" <dakr@kernel.org>
Link: https://lore.kernel.org/r/DCUC4SY6SRBD.1ZLHAIQZOC6KG@kernel.org

1 files changed, 52 insertions, 0 deletions

diff --git a/rust/kernel/alloc/allocator.rs b/rust/kernel/alloc/allocator.rs
index 2692cf90c948..84ee7e9d7b0e 100644
--- a/rust/kernel/alloc/allocator.rs
+++ b/rust/kernel/alloc/allocator.rs
@@ -15,8 +15,12 @@ use core::ptr::NonNull;
 
 use crate::alloc::{AllocError, Allocator};
 use crate::bindings;
+use crate::page;
 use crate::pr_warn;
 
+mod iter;
+pub use self::iter::VmallocPageIter;
+
 /// The contiguous kernel allocator.
 ///
 /// `Kmalloc` is typically used for physically contiguous allocations up to page size, but also
@@ -142,6 +146,54 @@ unsafe impl Allocator for Kmalloc {
     }
 }
 
+impl Vmalloc {
+    /// Convert a pointer to a [`Vmalloc`] allocation to a [`page::BorrowedPage`].
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// # use core::ptr::{NonNull, from_mut};
+    /// # use kernel::{page, prelude::*};
+    /// use kernel::alloc::allocator::Vmalloc;
+    ///
+    /// let mut vbox = VBox::<[u8; page::PAGE_SIZE]>::new_uninit(GFP_KERNEL)?;
+    ///
+    /// {
+    ///     // SAFETY: By the type invariant of `Box` the inner pointer of `vbox` is non-null.
+    ///     let ptr = unsafe { NonNull::new_unchecked(from_mut(&mut *vbox)) };
+    ///
+    ///     // SAFETY:
+    ///     // `ptr` is a valid pointer to a `Vmalloc` allocation.
+    ///     // `ptr` is valid for the entire lifetime of `page`.
+    ///     let page = unsafe { Vmalloc::to_page(ptr.cast()) };
+    ///
+    ///     // SAFETY: There is no concurrent read or write to the same page.
+    ///     unsafe { page.fill_zero_raw(0, page::PAGE_SIZE)? };
+    /// }
+    /// # Ok::<(), Error>(())
+    /// ```
+    ///
+    /// # Safety
+    ///
+    /// - `ptr` must be a valid pointer to a [`Vmalloc`] allocation.
+    /// - `ptr` must remain valid for the entire duration of `'a`.
+    pub unsafe fn to_page<'a>(ptr: NonNull<u8>) -> page::BorrowedPage<'a> {
+        // SAFETY: `ptr` is a valid pointer to `Vmalloc` memory.
+        let page = unsafe { bindings::vmalloc_to_page(ptr.as_ptr().cast()) };
+
+        // SAFETY: `vmalloc_to_page` returns a valid pointer to a `struct page` for a valid pointer
+        // to `Vmalloc` memory.
+        let page = unsafe { NonNull::new_unchecked(page) };
+
+        // SAFETY:
+        // - `page` is a valid pointer to a `struct page`, given that by the safety requirements of
+        //   this function `ptr` is a valid pointer to a `Vmalloc` allocation.
+        // - By the safety requirements of this function `ptr` is valid for the entire lifetime of
+        //   `'a`.
+        unsafe { page::BorrowedPage::from_raw(page) }
+    }
+}
+
 // SAFETY: `realloc` delegates to `ReallocFunc::call`, which guarantees that
 // - memory remains valid until it is explicitly freed,
 // - passing a pointer to a valid memory allocation is OK,