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

Tom Talpey
2009-05-12T01:14:35Z

At 08:44 PM 5/11/2009, Trond Myklebust wrote:
>On Mon, 2009-05-11 at 19:13 -0500, Steve Wise wrote:
>> Trond Myklebust wrote:
>> > On Mon, 2009-05-11 at 17:25 -0500, Steve Wise wrote:
>> >
>> >> Hey Trond,
>> >>
>> >> Will this bug fix make 2.6.30?
>> >>
>> >> Thanks,
>> >>
>> >> Steve.
>> >>
>> >
>> > Not in the form it is in now. As I've said earlier, I'm not happy about
>> > the sunrpc layer having to circumvent ordinary type checking on
>> > non-sunrpc structures.
>> >
>> > Cheers
>> > Trond
>> How is it circumventing? It's currently incorrectly casting a pointer
>> into a u64. That seems just broken to me. Also, its really the sunrpc
>> rdma transport layer. It deals specifically with rdma. It _should_
>> know about rdma interfaces and types.
>
>The fact is that I'm simply not interested enough in rdma to tolerate
>hacks. If it isn't done cleanly, in a manner that I can maintain, then
>the whole transport layer comes out...

I know exactly what you want - it's not what the code does now and
it's not an accessor function to set the hardware's u64 field. What's
needed is a new function to manage the entire RDMA triplet, and the
memory registration behind it, in the OFA code side. Put the hardware
goop below the line, IOW. I'll dust up Steve on this.

Tom.