NFSv4 client's BUG?

[J. Bruce Fields]

On Mon, Jul 14, 2008 at 10:03:01AM +0800, Wei Yongjun wrote:
> J. Bruce Fields wrote:
>>> The error return by the server is NFSERR_OPENMODE in setattr.
>>> 646 nfsd4_setattr(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
>>> 647               struct nfsd4_setattr *setattr)
>>> 648 {
>>> 649         __be32 status = nfs_ok;
>>> 650
>>> 651         if (setattr->sa_iattr.ia_valid & ATTR_SIZE) {
>>> 652                 nfs4_lock_state();
>>> 653                 status = nfs4_preprocess_stateid_op(&cstate->current_fh,
>>> 654                         &setattr->sa_stateid, CHECK_FH | WR_STATE, NULL);
>>> 655                 nfs4_unlock_state();
>>>
>>> 2002 nfs4_preprocess_stateid_op(struct svc_fh *current_fh, stateid_t *stateid, int flags, struct file **filpp)
>>> ...
>>> 2049         if (stp) {
>>> 2050                 if ((status = nfs4_check_openmode(stp,flags)))
>>> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>> 2051                         goto out;
>>> 2052                 renew_client(stp->st_stateowner->so_client);
>>> 2053                 if (filpp)
>>> 2054                         *filpp = stp->st_vfs_file;
>>> 2055         }
>>>
>>> ...
>>>
>>> This error only happend when NFSv4 callback is enabled. See the   
>>> following code,  if cb->cb_set is 1, deleg will be alloc, if 
>>> cb->cb_set  is 0, the error will never happend. I confirm this by 
>>> drop callback tcp  packet used iptables.
>>> if cb->cb_set is 1, the message "NFSD: setlease failed [11], no   
>>> delegation" is print when open file with NFS4_SHARE_ACCESS_WRITE 
>>> mode,  when vfs_setlease(), the dir and inode count is 2 (may be one 
>>> is hold by  stp, the other is hold by dp), so the setlease for 
>>> F_WRLCK always fail.
>>>     
>>
>> That's normal; the server doesn't support write delegations (and doesn't
>> give out read delegations on write opens).
>>
>> So, is the problem occuring because the client is doing a setattr to
>> modify the size using a sequence id returned from a read delegation?
>>
>>   
> This happend in special case:
>
> OPEN (OPEN4_SHARE_ACCESS_BOTH)    --->                                    
>  <---      OPEN Reply OK
> SETATTR (size=0)                  --->
> OPEN (OPEN4_SHARE_ACCESS_READ)    --->
>                                     <---      SETATTR Reply NFSERR_OPENMODE
>                                     <---      OPEN Reply OK

Can you see which stateid the SETATTR was done with (in particular,
where did it come from)?  (You could just send me a link to the raw
capture if you'd like).

--b.