In Linux, block devices currently lack support for `copy_file_range`
API because the kernel does not provide the necessary functionality.
However, there is an ongoing upstream effort to address this
limitation: https://patchwork.kernel.org/project/dm-devel/cover/20240520102033.9361-1-nj.shetty@samsung.com/.
We have adopted this upstream kernel patch into the TrueNAS kernel and
made some additional modifications to enable block cloning specifically
for the zvol block device. This patch implements the platform-
independent portions of these changes for inclusion in OpenZFS.
This patch does not introduce any new functionality directly into
OpenZFS. The `TX_CLONE_RANGE` replay capability is only relevant when
zvols are migrated to non-TrueNAS systems that support Clone Range
replay in the ZIL.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Ameer Hamza <ahamza@ixsystems.com>
Closes#16901
Ameer Hamza
b952e061df