Re: [PATCH v3 00/10] Allocation APIs

From: Boqun Feng
Date: Fri Mar 29 2024 - 19:24:39 EST


On Fri, Mar 29, 2024 at 11:25:00AM -0700, Boqun Feng wrote:
> On Wed, Mar 27, 2024 at 10:35:53PM -0300, Wedson Almeida Filho wrote:
> > From: Wedson Almeida Filho <walmeida@xxxxxxxxxxxxx>
> >
> > Revamp how we use the `alloc` crate.
> >
> > We currently have a fork of the crate with changes to `Vec`; other
> > changes have been upstreamed (to the Rust project). This series removes
> > the fork and exposes all the functionality as extension traits.
> >
> > Additionally, it also introduces allocation flag parameters to all
> > functions that may result in allocations (e.g., `Box::new`, `Arc::new`,
> > `Vec::push`, etc.) without the `try_` prefix -- the names are available
> > because we build `alloc` with `no_global_oom_handling`.
> >
> > Lastly, the series also removes our reliance on the `allocator_api`
> > unstable feature.
> >
> > Long term, we still want to make such functionality available in
> > upstream Rust, but this allows us to make progress now and reduces our
> > maintainance burden.
> >
> > In summary:
> > 1. Removes `alloc` fork
> > 2. Removes use of `allocator_api` unstable feature
> > 3. Introduces flags (e.g., GFP_KERNEL, GFP_ATOMIC) when allocating
> >
> > ---
> >
>
> FWIW, I've put this into rust-dev:
>
> https://github.com/Rust-for-Linux/linux rust-dev
>
> a few adjustments are needed to work with other commits that have been
> queued in rust-dev, so I add an commit on the top for everyone's
> reference. (Besides this commit, I also removed all updates to our own
> alloc in Miguel's 1.77.0 compiler version bump patch)
>
> Regards,
> Boqun

As Miguel pointed out offline, the following is also needed:

diff --git a/rust/kernel/file.rs b/rust/kernel/file.rs
index a5930f0f2bc5..bf68a0ce9f14 100644
--- a/rust/kernel/file.rs
+++ b/rust/kernel/file.rs
@@ -350,7 +350,7 @@ impl DeferredFdCloser {
pub fn new() -> Result<Self, AllocError> {
Ok(Self {
// INVARIANT: The `file` pointer is null, so the type invariant does not apply.
- inner: Box::new(
+ inner: <Box<_> as BoxExt<_>>::new(
DeferredFdCloserInner {
twork: mem::MaybeUninit::uninit(),
file: core::ptr::null_mut(),