rust/helpers/dma.c | 16 ++++++++++++++++ rust/helpers/helpers.c | 1 + 2 files changed, 17 insertions(+) create mode 100644 rust/helpers/dma.c
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`
|
::: /home/fujita/build/um/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`
|
::: /home/fujita/build/um/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 <fujita.tomonori@gmail.com>
---
v2:
- add helpers for dma_(alloc|free)_attrs() instead of conditionally compile
v1: https://lore.kernel.org/lkml/20250409055501.136672-1-fujita.tomonori@gmail.com/
---
rust/helpers/dma.c | 16 ++++++++++++++++
rust/helpers/helpers.c | 1 +
2 files changed, 17 insertions(+)
create mode 100644 rust/helpers/dma.c
diff --git a/rust/helpers/dma.c b/rust/helpers/dma.c
new file mode 100644
index 000000000000..df8b8a77355a
--- /dev/null
+++ b/rust/helpers/dma.c
@@ -0,0 +1,16 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/dma-mapping.h>
+
+void *rust_helper_dma_alloc_attrs(struct device *dev, size_t size,
+ dma_addr_t *dma_handle, gfp_t flag,
+ unsigned long attrs)
+{
+ return dma_alloc_attrs(dev, size, dma_handle, flag, attrs);
+}
+
+void rust_helper_dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
+ dma_addr_t dma_handle, unsigned long attrs)
+{
+ dma_free_attrs(dev, size, cpu_addr, dma_handle, attrs);
+}
diff --git a/rust/helpers/helpers.c b/rust/helpers/helpers.c
index e1c21eba9b15..1e7c84df7252 100644
--- a/rust/helpers/helpers.c
+++ b/rust/helpers/helpers.c
@@ -14,6 +14,7 @@
#include "cpumask.c"
#include "cred.c"
#include "device.c"
+#include "dma.c"
#include "err.c"
#include "fs.c"
#include "io.c"
base-commit: c59026c0570a2a97ce2e7d5ae5e9c48fc841542b
--
2.43.0
On Fri, Apr 11, 2025 at 08:43:32AM +0900, FUJITA Tomonori wrote: > 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` > | > ::: /home/fujita/build/um/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` > | > ::: /home/fujita/build/um/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 <fujita.tomonori@gmail.com> Please add the new file to the corresponding MAINTAINERS entry. Whith that, Acked-by: Danilo Krummrich <dakr@kernel.org>
On Fri, 11 Apr 2025 11:51:03 +0200 Danilo Krummrich <dakr@kernel.org> wrote: > On Fri, Apr 11, 2025 at 08:43:32AM +0900, FUJITA Tomonori wrote: >> 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` >> | >> ::: /home/fujita/build/um/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` >> | >> ::: /home/fujita/build/um/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 <fujita.tomonori@gmail.com> > > Please add the new file to the corresponding MAINTAINERS entry. Whith that, > > Acked-by: Danilo Krummrich <dakr@kernel.org> I'll include the following changes in the next version. diff --git a/MAINTAINERS b/MAINTAINERS index 96b827049501..bec614ef35d9 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7020,6 +7020,7 @@ L: rust-for-linux@vger.kernel.org S: Supported W: https://rust-for-linux.com T: git https://github.com/Rust-for-Linux/linux.git alloc-next +F: rust/helpers/dma.c F: rust/kernel/dma.rs F: samples/rust/rust_dma.rs
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