Message-ID: <53DCEAE8.70707@gmail.com>
Date: Sat, 02 Aug 2014 21:43:04 +0800
From: Kinglong Mee <kinglongmee@gmail.com>
MIME-Version: 1.0
To: Trond Myklebust <trond.myklebust@primarydata.com>
CC: Jeff Layton <jlayton@primarydata.com>, Bruce Fields <bfields@fieldses.org>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
        Christoph Hellwig <hch@infradead.org>
Subject: Re: [PATCH v3 31/38] nfsd: Move the open owner hash table into struct
 nfs4_client
References: <1406684083-19736-1-git-send-email-jlayton@primarydata.com>	<1406684083-19736-32-git-send-email-jlayton@primarydata.com>	<53DCBFDB.5060808@gmail.com> <CAHQdGtTGNZsqZTCQhUboG1kE+bzb7p3K+5BxmusFG+qWMrVJzg@mail.gmail.com>
In-Reply-To: <CAHQdGtTGNZsqZTCQhUboG1kE+bzb7p3K+5BxmusFG+qWMrVJzg@mail.gmail.com>
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Sender: linux-nfs-owner@vger.kernel.org

On 8/2/2014 21:11, Trond Myklebust wrote:
> On Sat, Aug 2, 2014 at 6:39 AM, Kinglong Mee <kinglongmee@gmail.com> wrote:
>> On 7/30/2014 09:34, Jeff Layton wrote:
>>> From: Trond Myklebust <trond.myklebust@primarydata.com>
>>>
>>> Preparation for removing the client_mutex.
>>>
>>> Convert the open owner hash table into a per-client table and protect it
>>> using the nfs4_client->cl_lock spin lock.
>>>
>>> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
>>> ---
>>>  fs/nfsd/netns.h     |   1 -
>>>  fs/nfsd/nfs4state.c | 187 ++++++++++++++++++++++++----------------------------
>>>  fs/nfsd/state.h     |   1 +
>>>  3 files changed, 86 insertions(+), 103 deletions(-)
>>>
>>> diff --git a/fs/nfsd/netns.h b/fs/nfsd/netns.h
>>> index a71d14413d39..e1f479c162b5 100644
>>> --- a/fs/nfsd/netns.h
>>> +++ b/fs/nfsd/netns.h
>>> @@ -63,7 +63,6 @@ struct nfsd_net {
>>>       struct rb_root conf_name_tree;
>>>       struct list_head *unconf_id_hashtbl;
>>>       struct rb_root unconf_name_tree;
>>> -     struct list_head *ownerstr_hashtbl;
>>
>> I send a patch "NFSD: Rervert "knfsd: locks: flag NFSv4-owned locks"" before,
>> http://comments.gmane.org/gmane.linux.nfs/64382
>>
>> nfsd needs the hashtbl to find the lockowner for locking by owner from
>> fl->fl_owner stored in struct file_lock, but without nfs_client.
> 
> Why? We're not currently doing that.

Although not doing that right now, but there is a bug for getting the right ld_owner
in nfs4_set_lock_denied.

If denying locks, vfs don't copy fl->fl_lmops to the returned file_lock, so that,
fl->fl_lmops always be NULL, nfsd never return the owner who holds the conflock.

If we want fix this problem, needs finding the lockowner from struct file_lock.

thanks,
Kinglong Mee

> 
>> If moving the hashtbl to nfs_client, it's hard to finding the lockowner for locking.
>