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Date: Mon, 12 Aug 2013 04:47:52 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Josef Bacik <jbacik@fusionio.com>
Cc: Christoph Hellwig <hch@infradead.org>, Mark Fasheh <mfasheh@suse.de>,
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Subject: Re: [PATCH][RESEND] vfs: allow /proc/PID/maps to get device from stat
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On Thu, Aug 08, 2013 at 11:44:54AM -0400, Josef Bacik wrote:
> On Thu, Aug 08, 2013 at 06:48:05AM -0700, Christoph Hellwig wrote:
> > On Thu, Aug 08, 2013 at 09:02:07AM -0400, Josef Bacik wrote:
> > > This won't work, try having 10000 subvolumes with dirty inodes and do sync then
> > > go skiing, you'll have time :).  Thanks,
> > 
> > Why would the dirty inodes make any difference?  If you share the bdi
> > between the subvolumes the sync workflow should be exactly the same
> > still.
> > 
> 
> If we could dis-entangle vfsmounts from sb's and have it so you could have
> multiple vfsmounts with just one sb that would solve at least the in-kernel
> confusion, but I think we still have the userspace confusion.  Thanks,

I think it would mostly solve userspace confusion, as userspace only
sees mounts and the device names.

But please fix this up properly instead of propagating the effects of
the nasty btrfs hack that should never have been merged in that form
further up the stack.