diff options
Diffstat (limited to 'rust/kernel/alloc/allocator.rs')
-rw-r--r-- | rust/kernel/alloc/allocator.rs | 19 |
1 files changed, 6 insertions, 13 deletions
diff --git a/rust/kernel/alloc/allocator.rs b/rust/kernel/alloc/allocator.rs index 229642960cd1..e6ea601f38c6 100644 --- a/rust/kernel/alloc/allocator.rs +++ b/rust/kernel/alloc/allocator.rs @@ -18,23 +18,16 @@ pub(crate) unsafe fn krealloc_aligned(ptr: *mut u8, new_layout: Layout, flags: F // Customized layouts from `Layout::from_size_align()` can have size < align, so pad first. let layout = new_layout.pad_to_align(); - let mut size = layout.size(); - - if layout.align() > bindings::ARCH_SLAB_MINALIGN { - // The alignment requirement exceeds the slab guarantee, thus try to enlarge the size - // to use the "power-of-two" size/alignment guarantee (see comments in `kmalloc()` for - // more information). - // - // Note that `layout.size()` (after padding) is guaranteed to be a multiple of - // `layout.align()`, so `next_power_of_two` gives enough alignment guarantee. - size = size.next_power_of_two(); - } + // Note that `layout.size()` (after padding) is guaranteed to be a multiple of `layout.align()` + // which together with the slab guarantees means the `krealloc` will return a properly aligned + // object (see comments in `kmalloc()` for more information). + let size = layout.size(); // SAFETY: // - `ptr` is either null or a pointer returned from a previous `k{re}alloc()` by the // function safety requirement. - // - `size` is greater than 0 since it's either a `layout.size()` (which cannot be zero - // according to the function safety requirement) or a result from `next_power_of_two()`. + // - `size` is greater than 0 since it's from `layout.size()` (which cannot be zero according + // to the function safety requirement) unsafe { bindings::krealloc(ptr as *const core::ffi::c_void, size, flags.0) as *mut u8 } } |