On 3/18/2016 7:31 AM, Robin Murphy wrote:
> On 17/03/16 22:02, Sinan Kaya wrote:
>> Moving the default implementation of swiotlb_dma_to_phys and
>> swiotlb_phys_to_dma functions to dma-mapping.h so that we can get
>> rid of the duplicate code in multiple ARCH.
>>
>> Signed-off-by: Sinan Kaya <okaya@xxxxxxxxxxxxxx>
>> ---
>> arch/arm64/include/asm/dma-mapping.h | 14 --------------
>> arch/ia64/include/asm/dma-mapping.h | 14 --------------
>> arch/mips/include/asm/mach-generic/dma-coherence.h | 16 ----------------
>> arch/tile/include/asm/dma-mapping.h | 14 --------------
>> arch/unicore32/include/asm/dma-mapping.h | 14 --------------
>> arch/x86/include/asm/dma-mapping.h | 13 -------------
>> arch/xtensa/include/asm/dma-mapping.h | 14 --------------
>> include/linux/dma-mapping.h | 14 ++++++++++++++
>> 8 files changed, 14 insertions(+), 99 deletions(-)
>
> [...]
>
>> diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
>> index 728ef07..871d620 100644
>> --- a/include/linux/dma-mapping.h
>> +++ b/include/linux/dma-mapping.h
>> @@ -683,4 +683,18 @@ static inline int dma_mmap_writecombine(struct device *dev,
>> #define dma_unmap_len_set(PTR, LEN_NAME, VAL) do { } while (0)
>> #endif
>>
>> +#ifndef swiotlb_phys_to_dma
>> +static inline dma_addr_t swiotlb_phys_to_dma(struct device *dev, phys_addr_t paddr)
>> +{
>> + return paddr;
>> +}
>> +#endif
>> +
>> +#ifndef swiotlb_dma_to_phys
>> +static inline phys_addr_t swiotlb_dma_to_phys(struct device *dev, dma_addr_t daddr)
>> +{
>> + return daddr;
>> +}
>> +#endif
>> +
>> #endif
>>
>
> Could the default definition not be pushed all the way down into swiotlb.c (or at least swiotlb.h)?
I can do that but then we lose the inlining capability of the compiler. This could cost
performance penalty on architectures using it.
I tried moving it to swiotlb.h. swiotlb.h seems to be only used by swiotlb.c file. I could try
including it into dma-mapping.h and then moving the definitions into swiotlb.h file.
Let me give this a try.
>
> Robin.
>
--
Sinan Kaya
Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project
