Regarding remap_pfn_page

[Rajat Sharma]

On Thu, Jul 21, 2011 at 11:48 PM, mindentropy <mindentropy at gmail.com> wrote:
>>Sorry to kicks in...
> Was wondering where you were :)
>
>>hm, quite likely you run out of contigous virtual address space that
>>as big as you requested... in above, you requested 16 MiB, right?
>
> Not virtual address space but physical page frames. Yes I requested 16MB.
> I want a huge chunk for dma for a high bandwidth pcie(16GB/s!) device . I am
> thinking in terms of no scatter gather but generally any sane device would
> have one.
>

do you see any performance implication of scatter-gather? I think
unless you reach limits, performance should not vary much. Just
curious to know what sort of device it is targeting 16GB/s?