kernel/linux.git/rust/helpers/dma.c, branch v6.19.12

rust: dma: add helpers for architectures without CONFIG_HAS_DMA

2025-12-16T12:20:14+00:00

Add dma_set_mask(), dma_set_coherent_mask(), dma_map_sgtable(), and dma_max_mapping_size() helpers to fix a build error when CONFIG_HAS_DMA is not enabled. Note that when CONFIG_HAS_DMA is enabled, they are included in both bindings_generated.rs and bindings_helpers_generated.rs. The former takes precedence so behavior remains unchanged in that case. This fixes the following build error on UML: error[E0425]: cannot find function `dma_set_mask` in crate `bindings` --> rust/kernel/dma.rs:46:38 | 46 | to_result(unsafe { bindings::dma_set_mask(self.as_ref().as_raw(), mask.value()) }) | ^^^^^^^^^^^^ help: a function with a similar name exists: `xa_set_mark` | ::: rust/bindings/bindings_generated.rs:24690:5 | 24690 | pub fn xa_set_mark(arg1: *mut xarray, index: ffi::c_ulong, arg2: xa_mark_t); | ---------------------------------------------------------------------------- similarly named function `xa_set_mark` defined here error[E0425]: cannot find function `dma_set_coherent_mask` in crate `bindings` --> rust/kernel/dma.rs:63:38 | 63 | to_result(unsafe { bindings::dma_set_coherent_mask(self.as_ref().as_raw(), mask.value()) }) | ^^^^^^^^^^^^^^^^^^^^^ help: a function with a similar name exists: `dma_coherent_ok` | ::: rust/bindings/bindings_generated.rs:52745:5 | 52745 | pub fn dma_coherent_ok(dev: *mut device, phys: phys_addr_t, size: usize) -> bool_; | ---------------------------------------------------------------------------------- similarly named function `dma_coherent_ok` defined here error[E0425]: cannot find function `dma_map_sgtable` in crate `bindings` --> rust/kernel/scatterlist.rs:212:23 | 212 | bindings::dma_map_sgtable(dev.as_raw(), sgt.as_ptr(), dir.into(), 0) | ^^^^^^^^^^^^^^^ help: a function with a similar name exists: `dma_unmap_sgtable` | ::: rust/bindings/bindings_helpers_generated.rs:1351:5 | 1351 | / pub fn dma_unmap_sgtable( 1352 | | dev: *mut device, 1353 | | sgt: *mut sg_table, 1354 | | dir: dma_data_direction, 1355 | | attrs: ffi::c_ulong, 1356 | | ); | |______- similarly named function `dma_unmap_sgtable` defined here error[E0425]: cannot find function `dma_max_mapping_size` in crate `bindings` --> rust/kernel/scatterlist.rs:356:52 | 356 | let max_segment = match unsafe { bindings::dma_max_mapping_size(dev.as_raw()) } { | ^^^^^^^^^^^^^^^^^^^^ not found in `bindings` error: aborting due to 4 previous errors Cc: stable@vger.kernel.org # v6.17+ Fixes: 101d66828a4ee ("rust: dma: add DMA addressing capabilities") Signed-off-by: FUJITA Tomonori Reviewed-by: David Gow Reviewed-by: Alice Ryhl Link: https://patch.msgid.link/20251204160639.364936-1-fujita.tomonori@gmail.com [ Use relative paths in the error splat; add 'dma' prefix. - Danilo ] Signed-off-by: Danilo Krummrich

rust: dma: add DMA addressing capabilities

2025-07-19T17:36:51+00:00

Implement `dma_set_mask()`, `dma_set_coherent_mask()` and `dma_set_mask_and_coherent()` in the `dma::Device` trait. Those methods are used to set up the device's DMA addressing capabilities. Reviewed-by: Abdiel Janulgue Reviewed-by: Daniel Almeida Reviewed-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/20250716150354.51081-3-dakr@kernel.org [ Add DmaMask::try_new(). - Danilo ] Signed-off-by: Danilo Krummrich

rust: helpers: Add dma_alloc_attrs() and dma_free_attrs()

2025-04-15T21:06:03+00:00

Add dma_alloc_attrs() and dma_free_attrs() helpers to fix a build error when CONFIG_HAS_DMA is not enabled. Note that when CONFIG_HAS_DMA is enabled, dma_alloc_attrs() and dma_free_attrs() are included in both bindings_generated.rs and bindings_helpers_generated.rs. The former takes precedence so behavior remains unchanged in that case. This fixes the following build error on UML: error[E0425]: cannot find function `dma_alloc_attrs` in crate `bindings` --> rust/kernel/dma.rs:171:23 | 171 | bindings::dma_alloc_attrs( | ^^^^^^^^^^^^^^^ help: a function with a similar name exists: `dma_alloc_pages` | ::: rust/bindings/bindings_generated.rs:44568:5 | 44568 | / pub fn dma_alloc_pages( 44569 | | dev: *mut device, 44570 | | size: usize, 44571 | | dma_handle: *mut dma_addr_t, 44572 | | dir: dma_data_direction, 44573 | | gfp: gfp_t, 44574 | | ) -> *mut page; | |___________________- similarly named function `dma_alloc_pages` defined here error[E0425]: cannot find function `dma_free_attrs` in crate `bindings` --> rust/kernel/dma.rs:293:23 | 293 | bindings::dma_free_attrs( | ^^^^^^^^^^^^^^ help: a function with a similar name exists: `dma_free_pages` | ::: rust/bindings/bindings_generated.rs:44577:5 | 44577 | / pub fn dma_free_pages( 44578 | | dev: *mut device, 44579 | | size: usize, 44580 | | page: *mut page, 44581 | | dma_handle: dma_addr_t, 44582 | | dir: dma_data_direction, 44583 | | ); | |______- similarly named function `dma_free_pages` defined here Fixes: ad2907b4e308 ("rust: add dma coherent allocator abstraction") Signed-off-by: FUJITA Tomonori Acked-by: Danilo Krummrich Link: https://lore.kernel.org/r/20250412000507.157000-1-fujita.tomonori@gmail.com [ Reworded for relative paths. - Miguel ] Signed-off-by: Miguel Ojeda