Re: [patch] Introduce CONFIG_HAS_DMA.

From: Cornelia Huck
Date: Thu May 31 2007 - 02:53:22 EST


On Wed, 30 May 2007 14:40:02 -0700,
"Williams, Dan J" <dan.j.williams@xxxxxxxxx> wrote:

> With the patch non-dma-architectures that try to build code with true
> dependencies on the DMA api will fail to link i.e.:
>
> CONFIG_DMA_ENGINE=y CONFIG_HAS_DMA=n ASYNC_MEMCPY=y
> CC init/version.o
> LD init/built-in.o
> LD .tmp_vmlinux1
> async_tx/built-in.o: In function `async_memcpy':
> xor.c:(.text+0x770): undefined reference to `dma_map_page'
> xor.c:(.text+0x798): undefined reference to `dma_map_page'
> xor.c:(.text+0x968): undefined reference to `dma_map_page'
>
> Now changing CONFIG_DMA_ENGINE to depend on HAS_DMA (which is more
> correct than saying !S390).

Makes sense.

> Results in:
> CONFIG_DMA_ENGINE=n CONFIG_HAS_DMA=n ASYNC_MEMCPY=y
> CC init/version.o
> LD init/built-in.o
> LD .tmp_vmlinux1
> KSYM .tmp_kallsyms1.S
> AS .tmp_kallsyms1.o
> LD .tmp_vmlinux2
> KSYM .tmp_kallsyms2.S
> AS .tmp_kallsyms2.o
> LD vmlinux
>
> This also allows include/asm-s390/dma-mapping.h to be dropped.

Cool. Thanks for looking into that.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/