On 8/14/24 9:32 PM, Boqun Feng wrote:
Hi Danilo,
On Mon, Aug 12, 2024 at 08:22:46PM +0200, Danilo Krummrich wrote:
Hi,
This patch series adds generic kernel allocator support for Rust, which so far
is limited to `kmalloc` allocations.
In order to abstain from (re-)adding unstable Rust features to the kernel, this
patch series does not extend the `Allocator` trait from Rust's `alloc` crate,
nor does it extend the `BoxExt` and `VecExt` extensions.
Instead, this series introduces a kernel specific `Allocator` trait, which is
implemented by the `Kmalloc`, `Vmalloc` and `KVmalloc` allocators, also
implemented in the context of this series.
As a consequence we need our own kernel `Box<T, A>` and `Vec<T, A>` types.
Additionally, this series adds the following type aliases:
```
pub type KBox<T> = Box<T, Kmalloc>;
pub type VBox<T> = Box<T, Vmalloc>;
pub type KVBox<T> = Box<T, KVmalloc>;
pub type KVec<T> = Vec<T, Kmalloc>;
pub type VVec<T> = Vec<T, Vmalloc>;
pub type KVVec<T> = Vec<T, KVmalloc>;
```
With that, we can start using the kernel `Box` and `Vec` types throughout the
tree and remove the now obolete extensions `BoxExt` and `VecExt`.
For a final cleanup, this series removes the last minor dependencies to Rust's
`alloc` crate and removes it from the entire kernel build.
The series ensures not to break the `rusttest` make target by implementing the
`allocator_test` module providing a stub implementation for all kernel
`Allocator`s.
This patch series passes all KUnit tests, including the ones added by this
series. Additionally, the tests were run with `kmemleak` and `KASAN` enabled,
without any issues.
This series is based on [1], which hit -mm/mm-unstable, and is also available
in [2].
[1] https://git.kernel.org/pub/scm/linux/kernel/git/dakr/linux.git/log/?h=mm/krealloc
[2] https://git.kernel.org/pub/scm/linux/kernel/git/dakr/linux.git/log/?h=rust/mm
Changes in v5:
- (safety) comment / documentation fixes suggested by Alice, Benno and Gary
- remove `Unique<T>` and implement `Send` and `Sync` for `Box` and `Vec`
- use `KMALLOC_MAX_SIZE` for `KVmalloc` test and add a `Kmalloc` test that
expects to fail for `KMALLOC_MAX_SIZE`
- create use constants `KREALLOC`, `VREALLOC` and `KVREALLOC` for
`ReallocFuncs`
- drop `Box::drop_contents` for now, will add it again, once I actually rebase
on the original patch that introduces it
I'm trying to put your series on rust-dev, but I hit a few conflicts due
to the conflict with `Box::drop_contents`, which has been in rust-dev
for a while. And the conflict is not that trivial for me to resolve.
So just a head-up, that's a requirement for me to put it on rust-dev for
more tests from my end ;-)
I'll rebase later on and send you a branch.
Regards,
Boqun
- improve usage of `size_of_val` in `Box`
- move `InPlaceInit` and `ForeignOwnable` impls into kbox.rs
- fix missing `Box` conversions in rnull.rs
- reworked `Cmalloc` to keep track of the size of memory allocations itself
- remove `GlobalAlloc` together with the `alloc` crate to avoid a linker error
- remove `alloc` from scripts/generate_rust_analyzer.py
[...]
