From: Matthew Wilcox <matthew@wil.cx>
To: Jan Kara <jack@suse.cz>
Cc: Dave Chinner <david@fromorbit.com>, linux-fsdevel@vger.kernel.org
Subject: Re: hole-punch vs fault
Date: Mon, 2 Dec 2013 08:58:25 -0700 [thread overview]
Message-ID: <20131202155825.GA11028@parisc-linux.org> (raw)
In-Reply-To: <20131202083318.GA2188@quack.suse.cz>
On Mon, Dec 02, 2013 at 09:33:18AM +0100, Jan Kara wrote:
> > Indeed, XIP could make use of the structures we already
> > have in the struct inode/address space to behave more like a normal
> > filesystem. We already use the mapping tree to store
> > per-page information that is used to serialise truncate vs page
> > faults, so why not make XIP do exactly the same thing?
> I believe that grabbing mmap_sem for writing during truncate (in case of
> ext2 around xip_truncate_page() & truncate_setsize() calls should do the
> trick. But I need to verify with lockdep that it doesn't introduce new
> locking problems.
Umm ... mmap_sem for write? On each of the tasks that have a file mmaped?
I know we have double_down that orders by memory address, but I don't
think we have an N_down_write().
--
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."
next prev parent reply other threads:[~2013-12-02 15:58 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-11-27 13:48 hole-punch vs fault Matthew Wilcox
2013-11-27 22:19 ` Jan Kara
2013-11-28 2:33 ` Matthew Wilcox
2013-11-28 3:30 ` Matthew Wilcox
2013-11-28 4:22 ` Dave Chinner
2013-11-28 4:44 ` Matthew Wilcox
2013-11-28 12:24 ` Matthew Wilcox
2013-11-28 22:12 ` Dave Chinner
2013-11-29 13:11 ` Matthew Wilcox
2013-12-01 21:52 ` Dave Chinner
2013-12-02 8:33 ` Jan Kara
2013-12-02 15:58 ` Matthew Wilcox [this message]
2013-12-02 20:11 ` Jan Kara
2013-12-02 20:13 ` Matthew Wilcox
2013-12-02 23:13 ` Jan Kara
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