From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Wilcox Subject: Re: Getting a lot of fs-generated information to user space Date: Fri, 12 Aug 2011 11:25:08 -0600 Message-ID: <20110812172508.GB29309@parisc-linux.org> References: <4E451917.6080306@jan-o-sch.net> <20110812123154.GA29309@parisc-linux.org> <4E453BA5.4090403@jan-o-sch.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-btrfs , linux-fsdevel@vger.kernel.org To: Jan Schmidt Return-path: In-Reply-To: <4E453BA5.4090403@jan-o-sch.net> List-ID: On Fri, Aug 12, 2011 at 04:41:41PM +0200, Jan Schmidt wrote: > After thinking twice, this has a drawback: I'd have to track state > between two read(2) calls, waiting for userspace to "pull" more data. That should be OK. You've got filp->private_data to store your state in, though you'll have to coordinate with btrfs' other use of ->private_data. Not hard, just a little bit of work. -- Matthew Wilcox Intel Open Source Technology Centre "Bill, look, we understand that you're interested in selling us this operating system, but compare it to ours. We can't possibly take such a retrograde step."