Reflinks for XFS are available in Fedora 27, so you no longer need to pull and compile xfsprogs from git.
To leverage reflinks in XFS, you need to create a file system with the reflink=1 flag.
[root@starscream mnt]# mkfs.xfs -m reflink=1 filesystem In my example I just created a file and mounted it on a loop device.
[root@starscream mnt]# mkfs.xfs -m reflink=1 test.img Then I’ll mount it
[root@starscream mnt]# mount -o loop test.