From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Serge E. Hallyn" Subject: Re: [RFC][PATCH 04/36] btrfs: Add checkpoint file operations Date: Mon, 4 May 2009 17:25:13 -0500 Message-ID: <20090504222513.GA32323@us.ibm.com> References: <63ff4e88102e10e86bffefd5e4445ab433ed51c0.1241462097.git.matthltc@us.ibm.com> <20090504214146.GA31338@us.ibm.com> <49FF69B4.3010700@cs.columbia.edu> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <49FF69B4.3010700-eQaUEPhvms7ENvBUuze7eA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Oren Laadan Cc: containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org List-Id: containers.vger.kernel.org Quoting Oren Laadan (orenl-eQaUEPhvms7ENvBUuze7eA@public.gmane.org): > > Serge E. Hallyn wrote: > > Quoting Matt Helsley (matthltc-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org): > > > > ... > > > >> diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c > >> index a7acfe6..f16be9d 100644 > >> --- a/fs/btrfs/super.c > >> +++ b/fs/btrfs/super.c > >> @@ -686,6 +686,7 @@ static const struct file_operations btrfs_ctl_fops = { > >> .unlocked_ioctl = btrfs_control_ioctl, > >> .compat_ioctl = btrfs_control_ioctl, > >> .owner = THIS_MODULE, > >> + .checkpoint = generic_file_checkpoint, > >> }; > > > > Do we really want this one? > > We need to checkpoint the open file regardless of whether the underlying > filesystem has snapshot capabilities. But maybe we need to refuse a checkpoint if a task is talking to the underlying btrfs filesystem? -serge