[Ocfs2-devel] [nov 29] what is ocfs2_lock() used for ?

[Tao Ma <tao.ma@oracle.com>]

Coly Li wrote:
> Hi List,
> 
> In Linus tree, I find ocfs2_lock() in fs/ocfs2/locks.c, this function can not be found from sles10
> sp2 tree. Also I don't find any other code calling ocfs2_lock().
It is an operation in file_operations. git log fs/ocfs2/locks.c shows 
that it is added by commit 53da4939f349d4edd283b043219221ca5b78e4d4.

commit 53da4939f349d4edd283b043219221ca5b78e4d4
Author: Mark Fasheh <mfasheh@suse.com>
Date:   Mon Jul 21 14:29:16 2008 -0700

     ocfs2: POSIX file locks support

     This is actually pretty easy since fs/dlm already handles the bulk 
of the work. The Ocfs2 userspace cluster stack module already uses 
fs/dlm as the underlying lock manager, so I only had to add the right calls.

     Cluster-aware POSIX locks ("plocks") can be turned off by the same 
means at UNIX locks - mount with 'noflocks', or create a local-only 
Ocfs2 volume. Internally, the file system uses two sets of 
file_operations, depending on whether cluster aware plocks is required. 
This turns out to be easier than implementing local-only versions of ->lock.

     Signed-off-by: Mark Fasheh <mfasheh@suse.com>

Regards,
Tao