FUSE Picking Up Copy-File-Range Support For Efficient Copy Operations

In addition to the recently covered work on making FUSE file-systems faster with eBPF, another separate optimization is on the way for the Linux kernel's FUSE bits that allow for file-systems to be implemented in user-space.

Queued in fuse-for-next is adding support for the copy_file_range() function. This allows for FUSE file-systems to support server-side copy or efficient copy/duplication/clone support, based upon the Linux kernel's copy_file_range syscall. This work is coming thanks to Red Hat.

The copy_file_range() system call allows for in-kernel copies between two file descriptors. GlusterFS has been one of the file-systems interested in this FUSE copy_file_range() support in order to implement copy-offloading / server-side-copy.

The copy_file_range support in the FUSE library (libfuse) is also pending until the kernel bits have been merged in the next cycle, which will be known as either Linux 4.20 or 5.0.