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-rw-r--r--rust/kernel/alloc/allocator_test.rs124
1 files changed, 0 insertions, 124 deletions
diff --git a/rust/kernel/alloc/allocator_test.rs b/rust/kernel/alloc/allocator_test.rs
deleted file mode 100644
index 90dd987d40e4..000000000000
--- a/rust/kernel/alloc/allocator_test.rs
+++ /dev/null
@@ -1,124 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-
-//! So far the kernel's `Box` and `Vec` types can't be used by userspace test cases, since all users
-//! of those types (e.g. `CString`) use kernel allocators for instantiation.
-//!
-//! In order to allow userspace test cases to make use of such types as well, implement the
-//! `Cmalloc` allocator within the `allocator_test` module and type alias all kernel allocators to
-//! `Cmalloc`. The `Cmalloc` allocator uses libc's `realloc()` function as allocator backend.
-
-#![allow(missing_docs)]
-
-use super::{flags::*, AllocError, Allocator, Flags};
-use core::alloc::Layout;
-use core::cmp;
-use core::ptr;
-use core::ptr::NonNull;
-
-/// The userspace allocator based on libc.
-pub struct Cmalloc;
-
-pub type Kmalloc = Cmalloc;
-pub type Vmalloc = Kmalloc;
-pub type KVmalloc = Kmalloc;
-
-impl Cmalloc {
- /// Returns a [`Layout`] that makes [`Kmalloc`] fulfill the requested size and alignment of
- /// `layout`.
- pub fn aligned_layout(layout: Layout) -> Layout {
- // Note that `layout.size()` (after padding) is guaranteed to be a multiple of
- // `layout.align()` which together with the slab guarantees means that `Kmalloc` will return
- // a properly aligned object (see comments in `kmalloc()` for more information).
- layout.pad_to_align()
- }
-}
-
-extern "C" {
- #[link_name = "aligned_alloc"]
- fn libc_aligned_alloc(align: usize, size: usize) -> *mut crate::ffi::c_void;
-
- #[link_name = "free"]
- fn libc_free(ptr: *mut crate::ffi::c_void);
-}
-
-// SAFETY:
-// - memory remains valid until it is explicitly freed,
-// - passing a pointer to a valid memory allocation created by this `Allocator` is always OK,
-// - `realloc` provides the guarantees as provided in the `# Guarantees` section.
-unsafe impl Allocator for Cmalloc {
- unsafe fn realloc(
- ptr: Option<NonNull<u8>>,
- layout: Layout,
- old_layout: Layout,
- flags: Flags,
- ) -> Result<NonNull<[u8]>, AllocError> {
- let src = match ptr {
- Some(src) => {
- if old_layout.size() == 0 {
- ptr::null_mut()
- } else {
- src.as_ptr()
- }
- }
- None => ptr::null_mut(),
- };
-
- if layout.size() == 0 {
- // SAFETY: `src` is either NULL or was previously allocated with this `Allocator`
- unsafe { libc_free(src.cast()) };
-
- return Ok(NonNull::slice_from_raw_parts(
- crate::alloc::dangling_from_layout(layout),
- 0,
- ));
- }
-
- // 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()) }.cast::<u8>();
- let dst = NonNull::new(dst).ok_or(AllocError)?;
-
- if flags.contains(__GFP_ZERO) {
- // SAFETY: The preceding calls to `libc_aligned_alloc` and `NonNull::new`
- // guarantee that `dst` points to memory of at least `layout.size()` bytes.
- unsafe { dst.as_ptr().write_bytes(0, layout.size()) };
- }
-
- if !src.is_null() {
- // SAFETY:
- // - `src` has previously been allocated with this `Allocator`; `dst` has just been
- // newly allocated, hence the memory regions do not overlap.
- // - both` src` and `dst` are properly aligned and valid for reads and writes
- unsafe {
- ptr::copy_nonoverlapping(
- src,
- dst.as_ptr(),
- cmp::min(layout.size(), old_layout.size()),
- )
- };
- }
-
- // SAFETY: `src` is either NULL or was previously allocated with this `Allocator`
- unsafe { libc_free(src.cast()) };
-
- Ok(NonNull::slice_from_raw_parts(dst, layout.size()))
- }
-}