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

Steve Wise
2009-05-14T13:40:55Z

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.