Message-ID: <4C68EDAE.5000201@cn.fujitsu.com>
Date: Mon, 16 Aug 2010 15:50:06 +0800
From: Bian Naimeng <biannm@cn.fujitsu.com>
To: Trond Myklebust <Trond.Myklebust@netapp.com>
CC: linux-nfs@vger.kernel.org
Subject: Re: [PATCH 2/2] We should clear NFS_DELEGATED_STATE after return
 delegation
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>>>>>> We should clear NFS_DELEGATED_STATE bit for inode->open_states after return delegation.

 ... snip ...

>> +
>> +	list_for_each_entry(state, &nfsi->open_states, inode_states) {
>> +		clear_bit(NFS_DELEGATED_STATE, &state->flags);
>> +	}
>> +
>>  	spin_unlock(&inode->i_lock);
>> -	return 0;
>> +	return err;
>>  }
>>  
> 
> I still don't see why this should be necessary. In the case of a server
> reboot or network partition, the state recovery thread ought to be
> taking care of this for us.
> 

   A open state can be found at nfsi->open_states and owner->so_states always, but
  it not be found at nfsi->open_files until we call nfs4_intent_set_file.

   At _nfs4_do_open, we will invoke nfs4_return_incompatible_delegation to return a 
  delegation,  a open stateid which set NFS_DELEGATED_STATE bit may not be found at
  nfsi->open_files, but it still at nfsi->open_states, so we do not clear 
  NFS_DELEGATED_STATE bit for it.

   Then _nfs4_do_open will find it by nfs4_get_open_state, and we still use it
  as a delegation, some error will occur.

-- 
Regards
Bian Naimeng

> Cheers
>   Trond