[openib-general] question: ib_umem page_size

[Michael S. Tsirkin]

Quoting r. Roland Dreier <rdreier at cisco.com>:
> Subject: Re: question: ib_umem page_size
> 
>     Michael> Roland, could you please clarify what does the page_size
>     Michael> field in struct ib_mem do?
> 
> It gives the page size for the user memory described by the struct.
> The idea was that if/when someone tries to optimize for huge pages,
> then the low-level driver can know that a region is using huge pages
> without having to walk through the page list and search for the
> minimum physically contiguous size.

Hmm, mthca_reg_user_mr seems to do:

len = sg_dma_len(&chunk->page_list[j]) >> shift

which means that dma_len must be a multiple of page size.

Is this intentional?

-- 
MST