rust: dma: add `Send` implementation for `CoherentAllocation`

2025-03-24T19:14:10Z

Stephen found a future build failure in linux-next [1]: error[E0277]: `*mut MyStruct` cannot be sent between threads safely --> samples/rust/rust_dma.rs:47:22 | 47 | impl pci::Driver for DmaSampleDriver { | ^^^^^^^^^^^^^^^ `*mut MyStruct` cannot be sent between threads safely It is caused by the interaction between commit 935e1d90bf6f ("rust: pci: require Send for Driver trait implementers") from the driver-core tree, which fixes a missing concurrency requirement, and commit 9901addae63b ("samples: rust: add Rust dma test sample driver") which adds a sample that does not satisfy that requirement. Add a `Send` implementation to `CoherentAllocation`, which allows the sample (and other future users) to satisfy it. Reported-by: Stephen Rothwell Closes: https://lore.kernel.org/linux-next/20250324215702.1515ba92@canb.auug.org.au/ [1] Signed-off-by: Danilo Krummrich Reviewed-by: Boqun Feng Link: https://lore.kernel.org/r/20250324174048.1075597-1-ojeda@kernel.org [ Added number to Closes. Fix typo spotted by Boqun. - Miguel ] Signed-off-by: Miguel Ojeda

rust: add dma coherent allocator abstraction

2025-03-20T20:44:46Z

Add a simple dma coherent allocator rust abstraction. Based on Andreas Hindborg's dma abstractions from the rnvme driver, which was also based on earlier work by Wedson Almeida Filho. Reviewed-by: Alice Ryhl Signed-off-by: Abdiel Janulgue Acked-by: Danilo Krummrich Link: https://lore.kernel.org/r/20250317185345.2608976-3-abdiel.janulgue@gmail.com Nacked-by: Christoph Hellwig [ Removed period. - Miguel ] Signed-off-by: Miguel Ojeda

linux/rust/kernel/dma.rs, branch v6.15

rust: dma: add `Send` implementation for `CoherentAllocation`

rust: add dma coherent allocator abstraction