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charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Stat-Signature: 6kjiyesaqa5ramzbnn8dfe4a48eeynu5 X-Rspamd-Queue-Id: 8573B10002B X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1722963633-73160 X-HE-Meta: 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 RAjfu/jy JYuzgE5d8ahuKw9YHx35hZB0gxCr4meQamGO+U69v3Q9/HJ/FdMecFnDlDYyGHKfl/I6Q7l/k4eBatiddcAs4C8teRfo1xqN3NUEv1HqKlTRVw5yKjaU2kvnIlwgP723KdR8jYcJe54K+A2UEZ1d+Ld7g8lZBXzZIegpKdL9qFgiTcBhQa1/Tnm6GxnG1uC0uuD+mmv5Y8ghYtzxAKNzdudwOMNy3HFQZ0fYyR7ljSWKK7UGqvNcDK6ulUwJP3+kTbpwZ4fL2HNxCDLYwAAk9y91GKKObDsym4fxygzs5jvQ2h3LaPzELFUto5F5aQkUZ+CZW55fSSL9J0RSo5/XWhGq8qSelIITEIKXHGi2ccX6RIB89Zok/ZkCbnSSLvasF9lSaUgMCvDBgEi8hL5w7AdksLdEv3isOPbUnUrtFNdWrCXir+FGl/gKEmsUCfQSr3bk4 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 05.08.24 17:19, Danilo Krummrich wrote: > Implement `Allocator` for `Vmalloc`, the kernel's virtually contiguous > allocator, typically used for larger objects, (much) larger than page > size. >=20 > All memory allocations made with `Vmalloc` end up in `vrealloc()`. >=20 > Reviewed-by: Alice Ryhl > Signed-off-by: Danilo Krummrich > --- > rust/helpers.c | 7 +++++++ > rust/kernel/alloc/allocator.rs | 32 +++++++++++++++++++++++++++++ > rust/kernel/alloc/allocator_test.rs | 1 + > 3 files changed, 40 insertions(+) >=20 > diff --git a/rust/helpers.c b/rust/helpers.c > index 9f7275493365..7406943f887d 100644 > --- a/rust/helpers.c > +++ b/rust/helpers.c > @@ -33,6 +33,7 @@ > #include > #include > #include > +#include > #include > #include >=20 > @@ -199,6 +200,12 @@ void *rust_helper_krealloc(const void *objp, size_t = new_size, gfp_t flags) > } > EXPORT_SYMBOL_GPL(rust_helper_krealloc); >=20 > +void *rust_helper_vrealloc(const void *p, size_t size, gfp_t flags) > +{ > +=09return vrealloc(p, size, flags); > +} > +EXPORT_SYMBOL_GPL(rust_helper_vrealloc); > + > /* > * `bindgen` binds the C `size_t` type as the Rust `usize` type, so we c= an > * use it in contexts where Rust expects a `usize` like slice (array) in= dices. > diff --git a/rust/kernel/alloc/allocator.rs b/rust/kernel/alloc/allocator= .rs > index c6ad1dd59dd0..bb55895cbd03 100644 > --- a/rust/kernel/alloc/allocator.rs > +++ b/rust/kernel/alloc/allocator.rs > @@ -9,6 +9,7 @@ >=20 > use crate::alloc::{AllocError, Allocator}; > use crate::bindings; > +use crate::pr_warn; >=20 > /// The contiguous kernel allocator. > /// > @@ -16,6 +17,12 @@ > /// `bindings::krealloc`. > pub struct Kmalloc; >=20 > +/// The virtually contiguous kernel allocator. > +/// > +/// The vmalloc allocator allocates pages from the page level allocator = and maps them into the > +/// contiguous kernel virtual space. > +pub struct Vmalloc; One thing that I should also have mentioned for `Kmalloc`, do we want these types to also have values? I don't think that we need them to be, so we could declare them as `pub enum 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. > @@ -61,6 +68,11 @@ fn krealloc() -> Self { > Self(bindings::krealloc) > } >=20 > + // INVARIANT: `vrealloc` satisfies the type invariants. This should be moved down a line. --- Cheers, Benno > + fn vrealloc() -> Self { > + Self(bindings::vrealloc) > + } > + > /// # Safety > /// > /// This method has the exact same safety requirements as `Allocator= ::realloc`. > @@ -141,6 +153,26 @@ unsafe fn alloc_zeroed(&self, layout: Layout) -> *mu= t u8 { > } > } >=20 > +unsafe impl Allocator for Vmalloc { > + unsafe fn realloc( > + ptr: Option>, > + layout: Layout, > + flags: Flags, > + ) -> Result, AllocError> { > + let realloc =3D ReallocFunc::vrealloc(); > + > + // TODO: Support alignments larger than PAGE_SIZE. > + if layout.align() > bindings::PAGE_SIZE { > + pr_warn!("Vmalloc does not support alignments larger than PA= GE_SIZE yet.\n"); > + return Err(AllocError); > + } > + > + // SAFETY: If not `None`, `ptr` is guaranteed to point to valid = memory, which was previously > + // allocated with this `Allocator`. > + unsafe { realloc.call(ptr, layout, flags) } I am a bit confused, for `Kmalloc`, you manually returned `NonNull::dangling` when allocating a zero-sized allocation, but here you don't? --- Cheers, Benno > + } > +} > + > #[global_allocator] > static ALLOCATOR: Kmalloc =3D Kmalloc; >=20 > diff --git a/rust/kernel/alloc/allocator_test.rs b/rust/kernel/alloc/allo= cator_test.rs > index 4785efc474a7..e7bf2982f68f 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( > -- > 2.45.2 >=20