[ofa-general] Re: [PATCH 2.6.30] xprtrdma: The frmr iova_start values are truncated by the nfs rdma client.

[Steve Wise]

Or Gerlitz wrote:
>> Trond Myklebust wrote
>>> All I should need to know is that I can advertise either dma handles 
>>> or kernel VAs
>
> Maybe its obvious to some people here, but may I ask why there's a 
> need to post either dma address or kernel virtual address? is it 
> application need? hardware (e.g IB vs iWARP vs  vendor implementation) 
> specific? or something else?
>
> Or.
>
>

The NFSRDMA transport uses Fast Register Memory Regions.  In this 
particular section of code, the NFSRDMA client is building a fastreg 
work request to bind a page list to a fastreg mr.  You can read about 
this in the IBTA spec on memory management extensions, or in the RDMA 
Verbs draft.


Steve.