Re: [nfsv4] NFS V4 OPEN delegation with CLAIM_DELEGATE_CUR

[Trond Myklebust <[e-mail]>]

On Sat, 2010-07-03 at 19:51 -0700, Jwu-Shyan Tarng wrote:
> Can someone help to answer the following questions? 
> 
> - Can the previous V4 OPEN with CLAIM=CLAIM_DELEGATE_CURimpact on
>  the later V4 OPEN delegation grant with different SHARE access
>  since CLAIM_DELEGATE_CURis done as part of recalling a delegation
> based on RFC? 
> 
> - There is a test sequence in the following: 
> 
> 1 OPEN for Readwhich gets READ delegation with delegation stateid,
> dstateid,andopen stateid, ostateid
> 2 Read with dstateid. 
>  - Expect NFS4_OK 
> 3 CLOSE with ostateid
>  - Expect NFS4_OK 
> 4 OPEN with CLAIM=CLAIM_DELEGATE_CURwith dstateid and get open
> stateid, ostateid2, back.
>  Read with dstateid. 
>  - Expect NFS4_OK 
>  Read with ostateid2. 
>  - Expect NFS4_OK 
> 5 OPEN for writefor this file (like OPEN upgrade)
>  Questions: 
>  1) Is the old dstateid still valid now?
>     If it is still valid, is this dstateid representing READ
> delegation or WRITE delegation?
>  2) Can this open for write get write delegation stateid besides open
> stateid returned to 
>     the client? 
>     If there is no delegation stateid returned to the client, is there
> any delegation existing 
>     on the client side? 

According to section 9.4.4 of RFC3530, the OPEN for write won't succeed
until the read delegation has been returned, so the answer is

  1) no
  2) yes

Cheers
  Trond