Re: [PATCH 01/22] scatterlist: Introduce sg_map helper functions

[Logan Gunthorpe]

On 14/04/17 02:35 AM, Christoph Hellwig wrote:
>> +
>>  static inline int is_dma_buf_file(struct file *);
>>  
>>  struct dma_buf_list {
> 
> I think the right fix here is to rename the operation to unmap_atomic
> and send out a little patch for that ASAP.

Ok, I can do that next week.

> I'd rather have separate functions for kmap vs kmap_atomic instead of
> the flags parameter.  And while you're at it just always pass the 0
> offset parameter instead of adding a wrapper..
> 
> Otherwise this looks good to me.

I settled on the flags because I thought the interface could be expanded
to do more things like automatically copy iomem to a bounce buffer (with
a flag). It'd also be possible to add things like vmap and
physical_address to the interface which would cover even more sg_page
users. All the implementations would then share the common offset
calculations, and switching between them becomes a matter of changing a
couple flags.

If you're still not convinced by the above arguments  then I'll change
it but I did have reasons for choosing to do it this way.

I am fine with removing the offset versions. I will make that change.

Thanks,

Logan