[PATCH] smb2 FSCTL_SRV_COPYCHUNK support

[David Disseldorp]

On Wed, 15 Feb 2012 13:49:03 +0100
Volker Lendecke <Volker.Lendecke at SerNet.DE> wrote:

> On a second thought: Why do we need copychunk in the VFS at
> all? We have pread and pwrite in both sync and async
> flavor. We could handle the copychunk stuff in the core smbd
> building upon those. Or are there native file systems that
> do copychunk?

Yes, btrfs via the BTRFS_IOC_CLONE_RANGE ioctl, and better yet it's
only a metadata operation. This is plumed in as part of the patchset.
Other COW based filesystems (ZFS etc.) may go down a similar path.

Cheers, David