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Date: Thu, 19 Jul 2007 17:38:10 +0100
From: Al Viro <viro@ftp.linux.org.uk>
To: Jan Engelhardt <jengelh@computergmbh.de>
Cc: Jacob A <jacoba51-tmp@yahoo.com>, linux-kernel@vger.kernel.org
Subject: Re: 2.4 Q: list of open files per inode?
Message-ID: <20070719163810.GV21668@ftp.linux.org.uk>
References: <581196.34917.qm@web57713.mail.re3.yahoo.com> <Pine.LNX.4.64.0707191339090.30033@fbirervta.pbzchgretzou.qr>
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On Thu, Jul 19, 2007 at 01:41:03PM +0200, Jan Engelhardt wrote:
> 
> On Jul 19 2007 02:01, Jacob A wrote:
> >
> > How can a device driver go over the  list of all the files that are open on a
> > specific inode instance?
> 
> pseudo-code:
> 
> task_list_lock;
> for each process; do
> 	lock_fdtable;
> 	for each filedescriptor; do
> 		do_something(fd->file_ptr);
> 	unlock_fdtable;
> task_list_unlock;

Not again...

There are other things that can keep file open.  SCM_RIGHTS, references
held by syscall in progress, etc., etc.

The real question is why does driver want to do that?  Details, please...