blaster4385/linux-IllusionX/rust/kernel/sync, branch v6.12.1

rust: sync: require `T: Sync` for `LockedBy::access`

2024-09-26T15:51:49Z

The `LockedBy::access` method only requires a shared reference to the owner, so if we have shared access to the `LockedBy` from several threads at once, then two threads could call `access` in parallel and both obtain a shared reference to the inner value. Thus, require that `T: Sync` when calling the `access` method. An alternative is to require `T: Sync` in the `impl Sync for LockedBy`. This patch does not choose that approach as it gives up the ability to use `LockedBy` with `!Sync` types, which is okay as long as you only use `access_mut`. Cc: stable@vger.kernel.org Fixes: 7b1f55e3a984 ("rust: sync: introduce `LockedBy`") Signed-off-by: Alice Ryhl Suggested-by: Boqun Feng Reviewed-by: Gary Guo Link: https://lore.kernel.org/r/20240915-locked-by-sync-fix-v2-1-1a8d89710392@google.com Signed-off-by: Miguel Ojeda

rust: Implement the smart pointer `InPlaceInit` for `Arc`

2024-08-18T21:10:53Z

For pinned and unpinned initialization of structs, a trait named `InPlaceInit` exists for uniform access. `Arc` did not implement `InPlaceInit` yet, although the functions already existed. The main reason for that, was that the trait itself returned a `Pin`. The `Arc` implementation of the kernel is already implicitly pinned. To enable `Arc` to implement `InPlaceInit` and to have uniform access, for in-place and pinned in-place initialization, an associated type is introduced for `InPlaceInit`. The new implementation of `InPlaceInit` for `Arc` sets `Arc` as the associated type. Older implementations use an explicit `Pin` as the associated type. The implemented methods for `Arc` are mostly moved from a direct implementation on `Arc`. There should be no user impact. The implementation for `ListArc` is omitted, because it is not merged yet. Link: https://github.com/Rust-for-Linux/linux/issues/1079 Signed-off-by: Alex Mantel Reviewed-by: Alice Ryhl Reviewed-by: Benno Lossin Link: https://lore.kernel.org/r/20240727042442.682109-1-alexmantel93@mailbox.org [ Removed "Rusts" (Benno). - Miguel ] Signed-off-by: Miguel Ojeda

rust: kernel: remove redundant imports

2024-05-05T17:22:25Z

Rust's `unused_imports` lint covers both unused and redundant imports. In the upcoming 1.78.0, the lint detects more cases of redundant imports [1], e.g.: error: the item `bindings` is imported redundantly --> rust/kernel/print.rs:38:9 | 38 | use crate::bindings; | ^^^^^^^^^^^^^^^ the item `bindings` is already defined by prelude Most cases are `use crate::bindings`, plus a few other items like `Box`. Thus clean them up. Note that, in the `bindings` case, the message "defined by prelude" above means the extern prelude, i.e. the `--extern` flags we pass. Link: https://github.com/rust-lang/rust/pull/117772 [1] Reviewed-by: Alice Ryhl Link: https://lore.kernel.org/r/20240401212303.537355-3-ojeda@kernel.org Signed-off-by: Miguel Ojeda

rust: sync: add `Arc::into_unique_or_drop`

2024-05-05T16:04:31Z

Decrement the refcount of an `Arc`, but handle the case where it hits zero by taking ownership of the now-unique `Arc`, instead of destroying and deallocating it. This is a dependency of the linked list that Rust Binder uses. The linked list uses this method as part of its `ListArc` abstraction [1]. Boqun Feng has authored the examples. Reviewed-by: Benno Lossin Reviewed-by: Boqun Feng Link: https://lore.kernel.org/r/20240402-linked-list-v1-1-b1c59ba7ae3b@google.com [1] Co-developed-by: Boqun Feng Signed-off-by: Boqun Feng Signed-off-by: Alice Ryhl Link: https://lore.kernel.org/r/20240402-arc-for-list-v4-2-54db6440a9a9@google.com [ Replace `try_new` with `new` in example since we now have the new allocation APIs. - Miguel ] Signed-off-by: Miguel Ojeda

rust: sync: add `ArcBorrow::from_raw`

2024-05-05T16:04:28Z

Allows access to a value in an `Arc` that is currently held as a raw pointer due to use of `Arc::into_raw`, without destroying or otherwise consuming that raw pointer. This is a dependency of the linked list that Rust Binder uses. The linked list uses this method when iterating over the linked list [1]. Reviewed-by: Benno Lossin Reviewed-by: Boqun Feng Link: https://lore.kernel.org/r/20240402-linked-list-v1-6-b1c59ba7ae3b@google.com [1] Signed-off-by: Alice Ryhl Link: https://lore.kernel.org/r/20240402-arc-for-list-v4-1-54db6440a9a9@google.com Signed-off-by: Miguel Ojeda

rust: kernel: remove usage of `allocator_api` unstable feature

2024-04-16T20:50:04Z

With the adoption of `BoxExt` and `VecExt`, we don't need the functions provided by this feature (namely the methods prefixed with `try_` and different allocator per collection instance). We do need `AllocError`, but we define our own as it is a trivial empty struct. Reviewed-by: Benno Lossin Signed-off-by: Wedson Almeida Filho Link: https://lore.kernel.org/r/20240328013603.206764-11-wedsonaf@gmail.com Signed-off-by: Miguel Ojeda

rust: init: update `init` module to take allocation flags

2024-04-16T20:50:04Z

This is the last component in the conversion for allocators to take allocation flags as parameters. Reviewed-by: Benno Lossin Signed-off-by: Wedson Almeida Filho Link: https://lore.kernel.org/r/20240328013603.206764-10-wedsonaf@gmail.com Signed-off-by: Miguel Ojeda

rust: sync: update `Arc` and `UniqueArc` to take allocation flags

2024-04-16T20:50:04Z

We also remove the `try_` prefix to align with how `Box` and `Vec` are providing methods now. `init` is temporarily updated with uses of GFP_KERNEL. These will be updated in a subsequent patch to take flags as well. Reviewed-by: Benno Lossin Signed-off-by: Wedson Almeida Filho Link: https://lore.kernel.org/r/20240328013603.206764-9-wedsonaf@gmail.com Signed-off-by: Miguel Ojeda

rust: alloc: introduce the `BoxExt` trait

2024-04-16T20:47:20Z

Make fallible versions of `new` and `new_uninit` methods available in `Box` even though it doesn't implement them because we build `alloc` with the `no_global_oom_handling` config. They also have an extra `flags` parameter that allows callers to pass flags to the allocator. Signed-off-by: Wedson Almeida Filho Reviewed-by: Boqun Feng Reviewed-by: Benno Lossin Link: https://lore.kernel.org/r/20240328013603.206764-7-wedsonaf@gmail.com [ Used `Box::write()` to avoid one `unsafe` block as suggested by Boqun. ] Signed-off-by: Miguel Ojeda

rust: kernel: stop using ptr_metadata feature

2024-02-18T20:22:27Z

The `byte_sub` method was stabilized in Rust 1.75.0. By using that method, we no longer need the unstable `ptr_metadata` feature for implementing `Arc::from_raw`. This brings us one step closer towards not using unstable compiler features. Reviewed-by: Benno Lossin Reviewed-by: Martin Rodriguez Reboredo Reviewed-by: Trevor Gross Signed-off-by: Alice Ryhl Link: https://lore.kernel.org/r/20240215104601.1267763-1-aliceryhl@google.com [ Reworded title. ] Signed-off-by: Miguel Ojeda