On Wed, Dec 14, 2011 at 02:42:38PM -0500, Ric Wheeler wrote: > On 12/14/2011 02:27 PM, Al Viro wrote: > >On Wed, Dec 14, 2011 at 02:22:07PM -0500, Ric Wheeler wrote: > > > >>We had an active thread a couple of years back that came out of the > >>reflink work and, at the time, there seemed to be moderately > >>positive support for adding a new system call that would fit this > >>use case (Joel Becker's copyfile()). > >> > >>Can we resurrect this effort? Is copyfile() still a good way to go, > >>or should we look at other hooks? > >copyfile(2) is probably a good way to go, provided that we do _not_ > >go baroque as it had happened the last time syscall had been discussed. > > > >IOW, to hell with progress reports, etc. - just a fastpath kind of > >thing, in the same kind of relationship to cp(1) as rename(2) is to mv(1). > >If it works - fine, if not - caller has to be ready to deal with handling > >cross-device case anyway. > > I think that this approach makes a lot of sense. Most of the > devices/targets that support the copy offload, will do it in very > reasonable amounts of time. The current NFSv4.2 draft rolls both the "fast" and "slow" cases into one operation: http://tools.ietf.org/html/draft-ietf-nfsv4-minorversion2-06#section-2 Perhaps we should ask for separate operations for the two cases. (Or at least a "please don't bother if this is going to take 8 hours" flag....) --b. > > Let me see if I can dig up some of the presentations from the NetApp > guys who presented overviews or the specifications from the IETF and > T10.... > > Ric > > -- > To unsubscribe from this list: send the line "unsubscribe linux-nfs" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
