Re: error[E0425]: cannot find function `dma_map_sgtable` in crate `bindings`

["Alexandre Courbot" <acourbot@nvidia.com>]

On Mon Dec 1, 2025 at 8:22 AM JST, kernel test robot wrote:
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head:   e69c7c175115c51c7f95394fc55425a395b3af59
> commit: 05aa6fb1c21d7fb9df735da24096d793223789d5 rust: scatterlist: Add abstraction for sg_table
> date:   3 months ago
> config: um-randconfig-r054-20251201 (https://download.01.org/0day-ci/archive/20251201/202512010734.GAsaWH7b-lkp@intel.com/config)
> compiler: clang version 22.0.0git (https://github.com/llvm/llvm-project b3428bb966f1de8aa48375ffee0eba04ede133b7)
> rustc: rustc 1.88.0 (6b00bc388 2025-06-23)
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251201/202512010734.GAsaWH7b-lkp@intel.com/reproduce)
>
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202512010734.GAsaWH7b-lkp@intel.com/
>
> All errors (new ones prefixed by >>):
>
>>> 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:465:5
>    |
>    465 | /     pub fn dma_unmap_sgtable(
>    466 | |         dev: *mut device,
>    467 | |         sgt: *mut sg_table,
>    468 | |         dir: dma_data_direction,
>    469 | |         attrs: ffi::c_ulong,
>    470 | |     );
>    | |______- 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`

A lot of the `dma_*` functions become static inline if `CONFIG_HAS_DMA`
is not set, resulting in no bindings being generated for them.