[PATCH v19 0/3] rust: xarray: Add a minimal abstraction for XArray

[Tamir Duberstein <tamird@gmail.com>]

This is a reimagining relative to earlier versions[0] by Asahi Lina and
Maíra Canal.

It is needed to support rust-binder, though this version only provides
enough machinery to support rnull.

Link: https://lore.kernel.org/rust-for-linux/20240309235927.168915-2-mcanal@igalia.com/ [0]
---
Changes in v19:
- Rebase on v6.15-rc2.
- Link to v18: https://lore.kernel.org/r/20250221-rust-xarray-bindings-v18-0-cbabe5ddfc32@gmail.com

Changes in v18:
- Add INVARIANT comment in `XArray::new`. (Danilo Krummrich)
- Replace destructuring with field access in
  `impl<T> From<StoreError<T>> for Error`. (Danilo Krummrich)
- Use enumerations in SAFETY comments (3x). (Danilo Krummrich)
- Link to v17: https://lore.kernel.org/r/20250218-rust-xarray-bindings-v17-0-f3a99196e538@gmail.com

Changes in v17:
- Drop patch "rust: remove redundant `as _` casts". (Danilo Krummrich)
- Drop trailers for shared commit from configfs series[0]. (Danilo
  Krummrich)
- Avoid shadowing expressions with .cast() calls. (Danilo Krummrich)
- Link to v16: https://lore.kernel.org/r/20250207-rust-xarray-bindings-v16-0-256b0cf936bd@gmail.com

Changes in v16:
- Extract prequel patch for `as _` casts. (Danilo Krummrich)
- Improve doc and safety comments. (Boqun Feng)
- Pull trailers for shared commit from configfs series[0]. (Andreas Hindborg, Alice Ryhl, Fiona Behrens)
- Link to configfs series: https://lore.kernel.org/rust-for-linux/20250131-configfs-v1-1-87947611401c@kernel.org/
- Link to v15: https://lore.kernel.org/r/20250206-rust-xarray-bindings-v15-0-a22b5dcacab3@gmail.com

Changes in v15:
- Rebase on v6.14-rc1.
- Add MAINTAINERS entry.
- Link to v14: https://lore.kernel.org/r/20241217-rust-xarray-bindings-v14-0-9fef3cefcb41@gmail.com

Changes in v14:
- Remove TODO made stale by Gary Guo's FFI type series.
- Link: https://lore.kernel.org/all/20240913213041.395655-5-gary@garyguo.net/
- Link to v13: https://lore.kernel.org/r/20241213-rust-xarray-bindings-v13-0-8655164e624f@gmail.com

Changes in v13:
- Replace `bool::then` with `if`. (Miguel Ojeda)
- Replace `match` with `let` + `if`. (Miguel Ojeda)
- Link to v12: https://lore.kernel.org/r/20241212-rust-xarray-bindings-v12-0-59ab9b1f4d2e@gmail.com

Changes in v12:
- Import `core::ptr::NonNull`. (Alice Ryhl)
- Introduce `StoreError` to allow `?` to be used with `Guard::store`.
  (Alice Ryhl)
- Replace `{crate,core}::ffi::c_ulong` and clarify TODO with respect to
  `usize`. (Alice Ryhl)
- Drop `T: Sync` bound on `impl Sync for XArray<T>`. (Alice Ryhl)
- Reword `Send` and `Sync` safety comments to match the style used in
  `lock.rs`. (Alice Ryhl and Andreas
  Hindborg)
- Link to v11: https://lore.kernel.org/r/20241203-rust-xarray-bindings-v11-0-58a95d137ec2@gmail.com

Changes in v11:
- Consolidate imports. (Alice Ryhl)
- Use literal `0` rather than `MIN`. (Alice Ryhl)
- Use bulleted list in SAFETY comment. (Alice Ryhl)
- Document (un)locking behavior of `Guard::store`. (Alice Ryhl)
- Document Normal API behavior WRT `XA_ZERO_ENTRY`. (Alice Ryhl)
- Rewrite `unsafe impl Sync` SAFETY comment. (Andreas Hindborg)
- Link to v10: https://lore.kernel.org/r/20241120-rust-xarray-bindings-v10-0-a25b2b0bf582@gmail.com

Changes in v10:
- Guard::get takes &self instead of &mut self. (Andreas Hindborg)
- Guard is !Send. (Boqun Feng)
- Add Inspired-by tags. (Maíra Canal and Asahi Lina)
- Rebase on linux-next, use NotThreadSafe. (Alice Ryhl)
- Link to v9: https://lore.kernel.org/r/20241118-rust-xarray-bindings-v9-0-3219cdb53685@gmail.com

---
Tamir Duberstein (3):
      rust: types: add `ForeignOwnable::PointedTo`
      rust: xarray: Add an abstraction for XArray
      MAINTAINERS: add entry for Rust XArray API

 MAINTAINERS                     |  11 ++
 rust/bindings/bindings_helper.h |   6 +
 rust/helpers/helpers.c          |   1 +
 rust/helpers/xarray.c           |  28 ++++
 rust/kernel/alloc/kbox.rs       |  38 +++---
 rust/kernel/lib.rs              |   1 +
 rust/kernel/miscdevice.rs       |  10 +-
 rust/kernel/pci.rs              |   2 +-
 rust/kernel/platform.rs         |   2 +-
 rust/kernel/sync/arc.rs         |  21 +--
 rust/kernel/types.rs            |  46 ++++---
 rust/kernel/xarray.rs           | 275 ++++++++++++++++++++++++++++++++++++++++
 12 files changed, 392 insertions(+), 49 deletions(-)
---
base-commit: 9d7a0577c9db35c4cc52db90bc415ea248446472
change-id: 20241020-rust-xarray-bindings-bef514142968

Best regards,
-- 
Tamir Duberstein <tamird@gmail.com>