Re: New copyfile system call - discuss before LSF?

[Jeremy Allison]

On Thu, Feb 21, 2013 at 01:51:53PM +0000, Myklebust, Trond wrote:
> On Thu, 2013-02-21 at 12:37 +0100, Ric Wheeler wrote:
> > We have debated the need to have a system call to allow for offloading copy 
> > operations, for example to an NFS server (part to the new NFS 4.2 
> > specification), SCSI target device (two different SCSI commands do this), local 
> > file systems (reflink, etc) and I suspect many other possible parts of the stack 
> > could implement this.
> 
> sendfile64() pretty much already has the right arguments for a
> "copyfile", however it would be nice to add a 'flags' parameter: the
> NFSv4.2 version would use that to specify whether or not to copy file
> metadata.

What would be really nice is if sendfile allowed zero-copy
from network socket to a file descriptor. That would help
a *lot* of my small system OEMs (and no splice() just doesn't
cut it :-).

Jeremy.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/