From nobody Thu Sep 19 01:09:33 2024 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 69E8F157E9F; Tue, 23 Jul 2024 18:11:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721758287; cv=none; b=Y1etNrG7AstOkH8GOsfLuTPwZUJBHvWC6HNkcHTWOfAuV4xBQfVH9kBJoO9IXopn+1WfapOV+/tl/s85zlsPVXU7M6qHapGaReJN4UP+Izihfxczj5eYdHi5zQNcRBKZj1gv+McJKi97s/0otdzZfa6KB01Hiv56nx1Ho0a3AIU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721758287; c=relaxed/simple; bh=YaemE3GyNUw6k5SxqCko0qV/GMMCyuitkbWwSJz9u6E=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=dMqygJIOQ+EQVA5CvaMQklxPIAm+SeDxPotAAd/79PPomoMoj5tYTNEyigw1vNDGngGmHmljj+xlCZczsCYtAokNJO/lxrZfJrc61H7xJjTN2dtA+SnMs1wa6YiyacXuPXW9eWTjxSbOQfIXbnXhtXsZL7OvHTFTJIMVghRzSJw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=baOAej1A; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="baOAej1A" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DBEB5C4AF11; Tue, 23 Jul 2024 18:11:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1721758287; bh=YaemE3GyNUw6k5SxqCko0qV/GMMCyuitkbWwSJz9u6E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=baOAej1Au7/hHblUtzSZcJOHCZz7qZr12SRUNNlEDYgjYE8epT7uQ6Ol6uKD0vVle 7KTQvroSucEVwHrGu82BmmATVO34yILswc2nfJqeTGChptNBIA2IaOeaev9rzZjGsg 5meeIrkW+uA5ZeBIitR9pR/a4Y8ngqdWbvCYEcf4QU18vwY3kKTPbK8bMyNMke3u0Z 4h8SOfuWi3fpJrF8AO46vqQI0DbAHLPLmlZdTIpdjq4+hDc6KtS4WMcxrWRSzvknT3 S8FSd0onOAXFkJCFP9n4LqJ67ES+ojOTTatk9WwKYHOAzbWDV9DJzwkMfmXPBErcuD b2mfW9M/rKnEQ== From: Danilo Krummrich To: ojeda@kernel.org, alex.gaynor@gmail.com, wedsonaf@gmail.com, boqun.feng@gmail.com, gary@garyguo.net, bjorn3_gh@protonmail.com, benno.lossin@proton.me, a.hindborg@samsung.com, aliceryhl@google.com, akpm@linux-foundation.org Cc: daniel.almeida@collabora.com, faith.ekstrand@collabora.com, boris.brezillon@collabora.com, lina@asahilina.net, mcanal@igalia.com, zhiw@nvidia.com, acurrid@nvidia.com, cjia@nvidia.com, jhubbard@nvidia.com, airlied@redhat.com, ajanulgu@redhat.com, lyude@redhat.com, linux-kernel@vger.kernel.org, rust-for-linux@vger.kernel.org, linux-mm@kvack.org, Danilo Krummrich Subject: [PATCH v2 06/23] rust: alloc: implement `Vmalloc` allocator Date: Tue, 23 Jul 2024 20:09:55 +0200 Message-ID: <20240723181024.21168-7-dakr@kernel.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240723181024.21168-1-dakr@kernel.org> References: <20240723181024.21168-1-dakr@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Implement `Allocator` for `Vmalloc`, the kernel's virtually contiguous allocator, typically used for larger objects, (much) larger than page size. All memory allocations made with `Vmalloc` end up in `vrealloc()`. Signed-off-by: Danilo Krummrich --- rust/helpers.c | 8 ++++++++ rust/kernel/alloc/allocator.rs | 24 ++++++++++++++++++++++++ rust/kernel/alloc/allocator_test.rs | 1 + 3 files changed, 33 insertions(+) diff --git a/rust/helpers.c b/rust/helpers.c index 3df5217fb2ff..5ca7e4872ee8 100644 --- a/rust/helpers.c +++ b/rust/helpers.c @@ -30,6 +30,7 @@ #include #include #include +#include #include #include =20 @@ -165,6 +166,13 @@ rust_helper_krealloc(const void *objp, size_t new_size= , gfp_t flags) } EXPORT_SYMBOL_GPL(rust_helper_krealloc); =20 +void * __must_check __realloc_size(2) +rust_helper_vrealloc(const void *p, size_t size, gfp_t flags) +{ + return vrealloc(p, size, flags); +} +EXPORT_SYMBOL_GPL(rust_helper_vrealloc); + /* * `bindgen` binds the C `size_t` type as the Rust `usize` type, so we can * use it in contexts where Rust expects a `usize` like slice (array) indi= ces. diff --git a/rust/kernel/alloc/allocator.rs b/rust/kernel/alloc/allocator.rs index 397ae5bcc043..e9a3d0694f41 100644 --- a/rust/kernel/alloc/allocator.rs +++ b/rust/kernel/alloc/allocator.rs @@ -16,6 +16,12 @@ /// `bindings::krealloc`. pub struct Kmalloc; =20 +/// The virtually contiguous kernel allocator. +/// +/// The vmalloc allocator allocates pages from the page level allocator an= d maps them into the +/// contiguous kernel virtual space. +pub struct Vmalloc; + /// Returns a proper size to alloc a new object aligned to `new_layout`'s = alignment. fn aligned_size(new_layout: Layout) -> usize { // Customized layouts from `Layout::from_size_align()` can have size <= align, so pad first. @@ -58,6 +64,10 @@ fn krealloc() -> Self { Self(bindings::krealloc) } =20 + fn vrealloc() -> Self { + Self(bindings::vrealloc) + } + // SAFETY: `call` has the exact same safety requirements as `Allocator= ::realloc`. unsafe fn call( &self, @@ -136,6 +146,20 @@ unsafe fn alloc_zeroed(&self, layout: Layout) -> *mut = u8 { } } =20 +unsafe impl Allocator for Vmalloc { + unsafe fn realloc( + ptr: Option>, + layout: Layout, + flags: Flags, + ) -> Result, AllocError> { + let realloc =3D ReallocFunc::vrealloc(); + + // SAFETY: If not `None`, `ptr` is guaranteed to point to valid me= mory, which was previously + // allocated with this `Allocator`. + unsafe { realloc.call(ptr, layout, flags) } + } +} + #[global_allocator] static ALLOCATOR: Kmalloc =3D Kmalloc; =20 diff --git a/rust/kernel/alloc/allocator_test.rs b/rust/kernel/alloc/alloca= tor_test.rs index 3a0abe65491d..b2d7db492ba6 100644 --- a/rust/kernel/alloc/allocator_test.rs +++ b/rust/kernel/alloc/allocator_test.rs @@ -7,6 +7,7 @@ use core::ptr::NonNull; =20 pub struct Kmalloc; +pub type Vmalloc =3D Kmalloc; =20 unsafe impl Allocator for Kmalloc { unsafe fn realloc( --=20 2.45.2