summaryrefslogtreecommitdiffstats
path: root/rust/kernel/alloc
diff options
context:
space:
mode:
authorThomas Zimmermann <tzimmermann@suse.de>2025-04-07 13:47:40 +0200
committerThomas Zimmermann <tzimmermann@suse.de>2025-04-07 14:35:48 +0200
commit1afba39f9305fe4061a4e70baa6ebab9d41459da (patch)
tree67e7ed686bd75adc559025870151c4de6d649ced /rust/kernel/alloc
parentfbe43810d563a293e3de301141d33caf1f5d5c5a (diff)
parent0af2f6be1b4281385b618cb86ad946eded089ac8 (diff)
downloadlinux-1afba39f9305fe4061a4e70baa6ebab9d41459da.tar.gz
linux-1afba39f9305fe4061a4e70baa6ebab9d41459da.zip
Merge drm/drm-next into drm-misc-next
Backmerging to get v6.15-rc1 into drm-misc-next. Also fixes a build issue when enabling CONFIG_DRM_SCHED_KUNIT_TEST. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Diffstat (limited to 'rust/kernel/alloc')
-rw-r--r--rust/kernel/alloc/allocator.rs1
-rw-r--r--rust/kernel/alloc/allocator_test.rs18
-rw-r--r--rust/kernel/alloc/kbox.rs13
3 files changed, 31 insertions, 1 deletions
diff --git a/rust/kernel/alloc/allocator.rs b/rust/kernel/alloc/allocator.rs
index 439985e29fbc..aa2dfa9dca4c 100644
--- a/rust/kernel/alloc/allocator.rs
+++ b/rust/kernel/alloc/allocator.rs
@@ -80,6 +80,7 @@ impl ReallocFunc {
/// This method has the same guarantees as `Allocator::realloc`. Additionally
/// - it accepts any pointer to a valid memory allocation allocated by this function.
/// - memory allocated by this function remains valid until it is passed to this function.
+ #[inline]
unsafe fn call(
&self,
ptr: Option<NonNull<u8>>,
diff --git a/rust/kernel/alloc/allocator_test.rs b/rust/kernel/alloc/allocator_test.rs
index e3240d16040b..c37d4c0c64e9 100644
--- a/rust/kernel/alloc/allocator_test.rs
+++ b/rust/kernel/alloc/allocator_test.rs
@@ -62,6 +62,24 @@ unsafe impl Allocator for Cmalloc {
));
}
+ // ISO C (ISO/IEC 9899:2011) defines `aligned_alloc`:
+ //
+ // > The value of alignment shall be a valid alignment supported by the implementation
+ // [...].
+ //
+ // As an example of the "supported by the implementation" requirement, POSIX.1-2001 (IEEE
+ // 1003.1-2001) defines `posix_memalign`:
+ //
+ // > The value of alignment shall be a power of two multiple of sizeof (void *).
+ //
+ // and POSIX-based implementations of `aligned_alloc` inherit this requirement. At the time
+ // of writing, this is known to be the case on macOS (but not in glibc).
+ //
+ // Satisfy the stricter requirement to avoid spurious test failures on some platforms.
+ let min_align = core::mem::size_of::<*const crate::ffi::c_void>();
+ let layout = layout.align_to(min_align).map_err(|_| AllocError)?;
+ let layout = layout.pad_to_align();
+
// SAFETY: Returns either NULL or a pointer to a memory allocation that satisfies or
// exceeds the given size and alignment requirements.
let dst = unsafe { libc_aligned_alloc(layout.align(), layout.size()) } as *mut u8;
diff --git a/rust/kernel/alloc/kbox.rs b/rust/kernel/alloc/kbox.rs
index cb4ebea3b074..b77d32f3a58b 100644
--- a/rust/kernel/alloc/kbox.rs
+++ b/rust/kernel/alloc/kbox.rs
@@ -15,8 +15,9 @@ use core::pin::Pin;
use core::ptr::NonNull;
use core::result::Result;
-use crate::init::{InPlaceInit, InPlaceWrite, Init, PinInit};
+use crate::init::InPlaceInit;
use crate::types::ForeignOwnable;
+use pin_init::{InPlaceWrite, Init, PinInit, ZeroableOption};
/// The kernel's [`Box`] type -- a heap allocation for a single value of type `T`.
///
@@ -99,6 +100,10 @@ pub type VBox<T> = Box<T, super::allocator::Vmalloc>;
/// ```
pub type KVBox<T> = Box<T, super::allocator::KVmalloc>;
+// SAFETY: All zeros is equivalent to `None` (option layout optimization guarantee:
+// https://doc.rust-lang.org/stable/std/option/index.html#representation).
+unsafe impl<T, A: Allocator> ZeroableOption for Box<T, A> {}
+
// SAFETY: `Box` is `Send` if `T` is `Send` because the `Box` owns a `T`.
unsafe impl<T, A> Send for Box<T, A>
where
@@ -245,6 +250,12 @@ where
Ok(Self::new(x, flags)?.into())
}
+ /// Convert a [`Box<T,A>`] to a [`Pin<Box<T,A>>`]. If `T` does not implement
+ /// [`Unpin`], then `x` will be pinned in memory and can't be moved.
+ pub fn into_pin(this: Self) -> Pin<Self> {
+ this.into()
+ }
+
/// Forgets the contents (does not run the destructor), but keeps the allocation.
fn forget_contents(this: Self) -> Box<MaybeUninit<T>, A> {
let ptr = Self::into_raw(this);