Re: Implementation of delegation

[Yudong Gao <stgyd@umich.edu>]

Hi Trond,

Thanks for the prompt reply!

I find that in _nfs_do_open(), _nfs4_proc_open(), which do the RPC
call to the remote server, is always called before
nfs4_opendata_to_nfs4_state(), which will further invoke
nfs4_try_open_cached().

Does this means that whenever is file is opened, the client always
need to talk to the server first?

Thanks!

best,

Yudong

On Mon, Jul 12, 2010 at 2:48 PM, Trond Myklebust
<trond.myklebust@fys.uio.no> wrote:
> On Mon, 2010-07-12 at 14:37 -0700, Yudong Gao wrote:
>> Hi,
>>
>> I am reading the NFS source code of the file open function in kernel
>> 2.6.34, but I cannot find any implementation with delegation to allow
>> client to open a file locally without contacting the server. We are
>> tying to use delegation to do something interesting. So I am wondering
>> how much delegation support specified in the NFS 4.1 protocol is
>> available in the current Linux implementation?
>
> What's wrong with nfs4_try_open_cached()? It even works with NFSv4.0...
>
> Trond
>
>