From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3CCF4C00140 for ; Fri, 5 Aug 2022 15:44:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241191AbiHEPoV (ORCPT ); Fri, 5 Aug 2022 11:44:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48016 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241094AbiHEPns (ORCPT ); Fri, 5 Aug 2022 11:43:48 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9AC5B6C10C; Fri, 5 Aug 2022 08:43:29 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 069C3615C6; Fri, 5 Aug 2022 15:43:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 53C1FC433D6; Fri, 5 Aug 2022 15:43:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1659714208; bh=HAOVdUxq8jaN8hxBkozTGyjLT+4FNugXXDXdhGZG6tM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TG5HU1rY8S9DwUmYZgxqLqU10+KlNkaUdM9NTaBd6ZpLgR8kW4RWS9MTDglqsQn1H eiKYCzB1EG2vzK5YD4AEehkoFmdggEIzYUDMjCIamx4m4VOkrf6Xabu93J9ssxshy0 eS6Ss+yjs5n2pH8qf+61LsRmxw6gjEazKzTc5EWa+LsvdC+XrZuqy/bdAI+M8V2tXg 5G4S8ePEJrq1Q89AXW7g/KLZCF3G+YkHSQooGYuyE4yn0gtoahq5TqznR/FFXEud7D ryiiwXlXtr+Vc3GsBpGnEq9aoHYnjHPRVJYCbOhswWbkZlJY9574dhQL+rE9459RLq JHnMT/Y1MHq+A== From: Miguel Ojeda To: Linus Torvalds , Greg Kroah-Hartman Cc: rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, patches@lists.linux.dev, Jarkko Sakkinen , Miguel Ojeda , Alex Gaynor , Wedson Almeida Filho , Gary Guo , Matthew Bakhtiari , Boqun Feng , =?UTF-8?q?Bj=C3=B6rn=20Roy=20Baron?= Subject: [PATCH v9 08/27] rust: adapt `alloc` crate to the kernel Date: Fri, 5 Aug 2022 17:41:53 +0200 Message-Id: <20220805154231.31257-9-ojeda@kernel.org> In-Reply-To: <20220805154231.31257-1-ojeda@kernel.org> References: <20220805154231.31257-1-ojeda@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: rust-for-linux@vger.kernel.org This customizes the subset of the Rust standard library `alloc` that was just imported as-is, mainly by: - Adding SPDX license identifiers. - Skipping modules (e.g. `rc` and `sync`) via new `cfg`s. - Adding fallible (`try_*`) versions of existing infallible methods (i.e. returning a `Result` instead of panicking). Since the standard library requires stable/unstable attributes, these additions are annotated with: #[stable(feature = "kernel", since = "1.0.0")] Using "kernel" as the feature allows to have the additions clearly marked. The "1.0.0" version is just a placeholder. (At the moment, only one is needed, but in the future more fallible methods will be added). Co-developed-by: Alex Gaynor Signed-off-by: Alex Gaynor Co-developed-by: Wedson Almeida Filho Signed-off-by: Wedson Almeida Filho Co-developed-by: Gary Guo Signed-off-by: Gary Guo Co-developed-by: Matthew Bakhtiari Signed-off-by: Matthew Bakhtiari Signed-off-by: Miguel Ojeda --- rust/alloc/README.md | 33 +++++++++++++++++++++++++++++++++ rust/alloc/alloc.rs | 2 ++ rust/alloc/borrow.rs | 4 +++- rust/alloc/boxed.rs | 4 ++++ rust/alloc/collections/mod.rs | 2 ++ rust/alloc/lib.rs | 8 ++++++++ rust/alloc/raw_vec.rs | 9 +++++++++ rust/alloc/slice.rs | 2 ++ rust/alloc/vec/drain.rs | 2 ++ rust/alloc/vec/drain_filter.rs | 2 ++ rust/alloc/vec/into_iter.rs | 4 ++++ rust/alloc/vec/is_zero.rs | 2 ++ rust/alloc/vec/mod.rs | 25 +++++++++++++++++++++++++ rust/alloc/vec/partial_eq.rs | 2 ++ 14 files changed, 100 insertions(+), 1 deletion(-) create mode 100644 rust/alloc/README.md diff --git a/rust/alloc/README.md b/rust/alloc/README.md new file mode 100644 index 000000000000..c89c753720b5 --- /dev/null +++ b/rust/alloc/README.md @@ -0,0 +1,33 @@ +# `alloc` + +These source files come from the Rust standard library, hosted in +the repository, licensed under +"Apache-2.0 OR MIT" and adapted for kernel use. For copyright details, +see . + +Please note that these files should be kept as close as possible to +upstream. In general, only additions should be performed (e.g. new +methods). Eventually, changes should make it into upstream so that, +at some point, this fork can be dropped from the kernel tree. + + +## Rationale + +On one hand, kernel folks wanted to keep `alloc` in-tree to have more +freedom in both workflow and actual features if actually needed +(e.g. receiver types if we ended up using them), which is reasonable. + +On the other hand, Rust folks wanted to keep `alloc` as close as +upstream as possible and avoid as much divergence as possible, which +is also reasonable. + +We agreed on a middle-ground: we would keep a subset of `alloc` +in-tree that would be as small and as close as possible to upstream. +Then, upstream can start adding the functions that we add to `alloc` +etc., until we reach a point where the kernel already knows exactly +what it needs in `alloc` and all the new methods are merged into +upstream, so that we can drop `alloc` from the kernel tree and go back +to using the upstream one. + +By doing this, the kernel can go a bit faster now, and Rust can +slowly incorporate and discuss the changes as needed. diff --git a/rust/alloc/alloc.rs b/rust/alloc/alloc.rs index 6162b5c6d4c9..ca224a541770 100644 --- a/rust/alloc/alloc.rs +++ b/rust/alloc/alloc.rs @@ -1,3 +1,5 @@ +// SPDX-License-Identifier: Apache-2.0 OR MIT + //! Memory allocation APIs #![stable(feature = "alloc_module", since = "1.28.0")] diff --git a/rust/alloc/borrow.rs b/rust/alloc/borrow.rs index cb4e438f8bea..dde4957200d4 100644 --- a/rust/alloc/borrow.rs +++ b/rust/alloc/borrow.rs @@ -1,3 +1,5 @@ +// SPDX-License-Identifier: Apache-2.0 OR MIT + //! A module for working with borrowed data. #![stable(feature = "rust1", since = "1.0.0")] @@ -11,7 +13,7 @@ use core::ops::{Add, AddAssign}; #[stable(feature = "rust1", since = "1.0.0")] pub use core::borrow::{Borrow, BorrowMut}; -use crate::fmt; +use core::fmt; #[cfg(not(no_global_oom_handling))] use crate::string::String; diff --git a/rust/alloc/boxed.rs b/rust/alloc/boxed.rs index c07536f0d0ce..dcfe87b14f3a 100644 --- a/rust/alloc/boxed.rs +++ b/rust/alloc/boxed.rs @@ -1,3 +1,5 @@ +// SPDX-License-Identifier: Apache-2.0 OR MIT + //! A pointer type for heap allocation. //! //! [`Box`], casually referred to as a 'box', provides the simplest form of @@ -163,9 +165,11 @@ use crate::str::from_boxed_utf8_unchecked; #[cfg(not(no_global_oom_handling))] use crate::vec::Vec; +#[cfg(not(no_thin))] #[unstable(feature = "thin_box", issue = "92791")] pub use thin::ThinBox; +#[cfg(not(no_thin))] mod thin; /// A pointer type for heap allocation. diff --git a/rust/alloc/collections/mod.rs b/rust/alloc/collections/mod.rs index 628a5b155673..1eec265b28f8 100644 --- a/rust/alloc/collections/mod.rs +++ b/rust/alloc/collections/mod.rs @@ -1,3 +1,5 @@ +// SPDX-License-Identifier: Apache-2.0 OR MIT + //! Collection types. #![stable(feature = "rust1", since = "1.0.0")] diff --git a/rust/alloc/lib.rs b/rust/alloc/lib.rs index fd21b3671182..233bcd5e4654 100644 --- a/rust/alloc/lib.rs +++ b/rust/alloc/lib.rs @@ -1,3 +1,5 @@ +// SPDX-License-Identifier: Apache-2.0 OR MIT + //! # The Rust core allocation and collections library //! //! This library provides smart pointers and collections for managing @@ -192,6 +194,7 @@ extern crate std; extern crate test; // Module with internal macros used by other modules (needs to be included before other modules). +#[cfg(not(no_macros))] #[macro_use] mod macros; @@ -216,11 +219,16 @@ pub mod borrow; pub mod collections; #[cfg(not(no_global_oom_handling))] pub mod ffi; +#[cfg(not(no_fmt))] pub mod fmt; +#[cfg(not(no_rc))] pub mod rc; pub mod slice; +#[cfg(not(no_str))] pub mod str; +#[cfg(not(no_string))] pub mod string; +#[cfg(not(no_sync))] #[cfg(target_has_atomic = "ptr")] pub mod sync; #[cfg(all(not(no_global_oom_handling), target_has_atomic = "ptr"))] diff --git a/rust/alloc/raw_vec.rs b/rust/alloc/raw_vec.rs index 4be5f6cf9ca5..daf5f2da7168 100644 --- a/rust/alloc/raw_vec.rs +++ b/rust/alloc/raw_vec.rs @@ -1,3 +1,5 @@ +// SPDX-License-Identifier: Apache-2.0 OR MIT + #![unstable(feature = "raw_vec_internals", reason = "unstable const warnings", issue = "none")] use core::alloc::LayoutError; @@ -307,6 +309,12 @@ impl RawVec { } } + /// The same as `reserve_for_push`, but returns on errors instead of panicking or aborting. + #[inline(never)] + pub fn try_reserve_for_push(&mut self, len: usize) -> Result<(), TryReserveError> { + self.grow_amortized(len, 1) + } + /// Ensures that the buffer contains at least enough space to hold `len + /// additional` elements. If it doesn't already, will reallocate the /// minimum possible amount of memory necessary. Generally this will be @@ -421,6 +429,7 @@ impl RawVec { Ok(()) } + #[allow(dead_code)] fn shrink(&mut self, cap: usize) -> Result<(), TryReserveError> { assert!(cap <= self.capacity(), "Tried to shrink to a larger capacity"); diff --git a/rust/alloc/slice.rs b/rust/alloc/slice.rs index 199b3c9d0290..e444e97fa145 100644 --- a/rust/alloc/slice.rs +++ b/rust/alloc/slice.rs @@ -1,3 +1,5 @@ +// SPDX-License-Identifier: Apache-2.0 OR MIT + //! A dynamically-sized view into a contiguous sequence, `[T]`. //! //! *[See also the slice primitive type](slice).* diff --git a/rust/alloc/vec/drain.rs b/rust/alloc/vec/drain.rs index 5cdee0bd4da4..b6a5f98e4fcd 100644 --- a/rust/alloc/vec/drain.rs +++ b/rust/alloc/vec/drain.rs @@ -1,3 +1,5 @@ +// SPDX-License-Identifier: Apache-2.0 OR MIT + use crate::alloc::{Allocator, Global}; use core::fmt; use core::iter::{FusedIterator, TrustedLen}; diff --git a/rust/alloc/vec/drain_filter.rs b/rust/alloc/vec/drain_filter.rs index 3c37c92ae44b..b04fce041622 100644 --- a/rust/alloc/vec/drain_filter.rs +++ b/rust/alloc/vec/drain_filter.rs @@ -1,3 +1,5 @@ +// SPDX-License-Identifier: Apache-2.0 OR MIT + use crate::alloc::{Allocator, Global}; use core::ptr::{self}; use core::slice::{self}; diff --git a/rust/alloc/vec/into_iter.rs b/rust/alloc/vec/into_iter.rs index 9b84a1d9b4b6..f7a50e76691e 100644 --- a/rust/alloc/vec/into_iter.rs +++ b/rust/alloc/vec/into_iter.rs @@ -1,3 +1,5 @@ +// SPDX-License-Identifier: Apache-2.0 OR MIT + #[cfg(not(no_global_oom_handling))] use super::AsVecIntoIter; use crate::alloc::{Allocator, Global}; @@ -9,6 +11,7 @@ use core::iter::{ }; use core::marker::PhantomData; use core::mem::{self, ManuallyDrop}; +#[cfg(not(no_global_oom_handling))] use core::ops::Deref; use core::ptr::{self, NonNull}; use core::slice::{self}; @@ -123,6 +126,7 @@ impl IntoIter { } /// Forgets to Drop the remaining elements while still allowing the backing allocation to be freed. + #[allow(dead_code)] pub(crate) fn forget_remaining_elements(&mut self) { self.ptr = self.end; } diff --git a/rust/alloc/vec/is_zero.rs b/rust/alloc/vec/is_zero.rs index edf270db81d4..377f3d172777 100644 --- a/rust/alloc/vec/is_zero.rs +++ b/rust/alloc/vec/is_zero.rs @@ -1,3 +1,5 @@ +// SPDX-License-Identifier: Apache-2.0 OR MIT + use crate::boxed::Box; #[rustc_specialization_trait] diff --git a/rust/alloc/vec/mod.rs b/rust/alloc/vec/mod.rs index 3dc8a4fbba86..540787804cc2 100644 --- a/rust/alloc/vec/mod.rs +++ b/rust/alloc/vec/mod.rs @@ -1,3 +1,5 @@ +// SPDX-License-Identifier: Apache-2.0 OR MIT + //! A contiguous growable array type with heap-allocated contents, written //! `Vec`. //! @@ -1739,6 +1741,29 @@ impl Vec { } } + /// Tries to append an element to the back of a collection. + /// + /// # Examples + /// + /// ``` + /// let mut vec = vec![1, 2]; + /// vec.try_push(3).unwrap(); + /// assert_eq!(vec, [1, 2, 3]); + /// ``` + #[inline] + #[stable(feature = "kernel", since = "1.0.0")] + pub fn try_push(&mut self, value: T) -> Result<(), TryReserveError> { + if self.len == self.buf.capacity() { + self.buf.try_reserve_for_push(self.len)?; + } + unsafe { + let end = self.as_mut_ptr().add(self.len); + ptr::write(end, value); + self.len += 1; + } + Ok(()) + } + /// Removes the last element from a vector and returns it, or [`None`] if it /// is empty. /// diff --git a/rust/alloc/vec/partial_eq.rs b/rust/alloc/vec/partial_eq.rs index b0cf72577a1b..10ad4e492287 100644 --- a/rust/alloc/vec/partial_eq.rs +++ b/rust/alloc/vec/partial_eq.rs @@ -1,3 +1,5 @@ +// SPDX-License-Identifier: Apache-2.0 OR MIT + use crate::alloc::Allocator; #[cfg(not(no_global_oom_handling))] use crate::borrow::Cow; -- 2.37.1