diff options
author | Johannes Berg <johannes.berg@intel.com> | 2023-10-05 22:57:34 +0200 |
---|---|---|
committer | Kalle Valo <kvalo@kernel.org> | 2023-10-06 17:08:47 +0300 |
commit | 7d6904bf26b96ef087514cb7a8c50b62a4911c99 (patch) | |
tree | 2feaff8495d88c2102dc2e017b7afc5c58db02d6 /rust/alloc/raw_vec.rs | |
parent | 9418edf8ff01e7a4904aac1aca4864ecdea37593 (diff) | |
parent | 22061bfc57fe08c77141dc876b4af75603c4d61d (diff) |
Merge wireless into wireless-next
Resolve several conflicts, mostly between changes/fixes in
wireless and the locking rework in wireless-next. One of
the conflicts actually shows a bug in wireless that we'll
want to fix separately.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Diffstat (limited to 'rust/alloc/raw_vec.rs')
-rw-r--r-- | rust/alloc/raw_vec.rs | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/rust/alloc/raw_vec.rs b/rust/alloc/raw_vec.rs index 5db87eac53b78..65d5ce15828e4 100644 --- a/rust/alloc/raw_vec.rs +++ b/rust/alloc/raw_vec.rs @@ -6,7 +6,6 @@ use core::alloc::LayoutError; use core::cmp; use core::intrinsics; use core::mem::{self, ManuallyDrop, MaybeUninit, SizedTypeProperties}; -use core::ops::Drop; use core::ptr::{self, NonNull, Unique}; use core::slice; @@ -274,10 +273,15 @@ impl<T, A: Allocator> RawVec<T, A> { if T::IS_ZST || self.cap == 0 { None } else { - // We have an allocated chunk of memory, so we can bypass runtime - // checks to get our current layout. + // We could use Layout::array here which ensures the absence of isize and usize overflows + // and could hypothetically handle differences between stride and size, but this memory + // has already been allocated so we know it can't overflow and currently rust does not + // support such types. So we can do better by skipping some checks and avoid an unwrap. + let _: () = const { assert!(mem::size_of::<T>() % mem::align_of::<T>() == 0) }; unsafe { - let layout = Layout::array::<T>(self.cap).unwrap_unchecked(); + let align = mem::align_of::<T>(); + let size = mem::size_of::<T>().unchecked_mul(self.cap); + let layout = Layout::from_size_align_unchecked(size, align); Some((self.ptr.cast().into(), layout)) } } @@ -465,11 +469,13 @@ impl<T, A: Allocator> RawVec<T, A> { assert!(cap <= self.capacity(), "Tried to shrink to a larger capacity"); let (ptr, layout) = if let Some(mem) = self.current_memory() { mem } else { return Ok(()) }; - + // See current_memory() why this assert is here + let _: () = const { assert!(mem::size_of::<T>() % mem::align_of::<T>() == 0) }; let ptr = unsafe { // `Layout::array` cannot overflow here because it would have // overflowed earlier when capacity was larger. - let new_layout = Layout::array::<T>(cap).unwrap_unchecked(); + let new_size = mem::size_of::<T>().unchecked_mul(cap); + let new_layout = Layout::from_size_align_unchecked(new_size, layout.align()); self.alloc .shrink(ptr, layout, new_layout) .map_err(|_| AllocError { layout: new_layout, non_exhaustive: () })? |