From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joel Becker <Joel.Becker@oracle.com>
Subject: Re: [PATCH 1/3] fs: Document the reflink(2) system
	call.
Date: Mon, 4 May 2009 00:12:39 -0700
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Cc: Christoph Hellwig <hch@infradead.org>, linux-fsdevel@vger.kernel.org,
        jmorris@namei.org, ocfs2-devel@oss.oracle.com, viro@zeniv.linux.org.uk
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On Mon, May 04, 2009 at 06:36:58PM +1200, Michael Kerrisk wrote:
> On Mon, May 4, 2009 at 2:46 PM, Joel Becker <Joel.Becker@oracle.com> wrot=
e:
> > On Sun, May 03, 2009 at 04:01:12AM -0400, Christoph Hellwig wrote:
> >> On Sat, May 02, 2009 at 11:15:01PM -0700, Joel Becker wrote:
> >> > int reflink(const char *oldpath, const char *newpath);
> >> >
> >> > The reflink(2) system call creates reference-counted links. =A0It cr=
eates
> >> > a new file that shares the data extents of the source file in a
> >> > copy-on-write fashion. =A0Its calling semantics are identical to lin=
k(2).
> >> > Once complete, programs see the new file as a completely separate en=
try.
> >>
> >> Just send this as a manpage to Michael, no need to duplicate a
> >> pseudo-manpage in the kernel tree.
> >
> > =A0 =A0 =A0 =A0The manpage style was just a convenient way to organize =
my
> > thoughts. =A0The goal was to document the behavior of reflink() for
> > implementors. =A0If the pseudo-manpage doesn't work, perhaps I'll try s=
ome
> > other form.
> =

> So, I'm late to this thread.  Is reflink() (to be) a user-visible syscall?

	Yes.  The actual call will be reflinkat(), as they're correct
that userspace can wrap reflink() around it.  I did have you on my todo
for notification as it settled down.

Joel

-- =


"Well-timed silence hath more eloquence than speech."  =

         - Martin Fraquhar Tupper

Joel Becker
Principal Software Developer
Oracle
E-mail: joel.becker@oracle.com
Phone: (650) 506-8127