Add reflink copy over SMB3.11 with new FSCTL_DUPLICATE_EXTENTS
Getting fantastic copy performance with cp --reflink over SMB3.11
using the new FSCTL_DUPLICATE_EXTENTS.
This FSCTL was added in the SMB3.11 dialect (testing was
against REFS file system) so have put it as a 3.11 protocol
specific operation ("vers=3.1.1" on the mount). Tested at
the SMB3 plugfest in Redmond.
It depends on the new FS Attribute (BLOCK_REFCOUNTING) which
is used to advertise support for the ability to do this ioctl
(if you can support multiple files pointing to the same block
than this refcounting ability or equivalent is needed to
support the new reflink-like duplicate extent SMB3 ioctl.
Signed-off-by: Steve French <steve.french@primarydata.com>
6 files changed