Mount LVM backup partition inside host on XEN

I have a XEN server (4.17) with a volume group vg0 and some volumes on it where one is a logical volume especially for Nextcloud e.g.: lvcreate -n nextcloud -L2000G vg0 mkfs.ext4 /dev/vg0/nextcloud These are my volumes:

# lvs                                                                                                                                                                                                                     
  LV                              VG  Attr         LSize   Pool Origin                 Data%  Meta%  Move Log Cpy%Sync Convert 
  nextcloud                       vg0 -wi-ao----   2,01t                                                                     
  root                            vg0 -wi-ao----  10,00g                                                                     
  swap                            vg0 -wi-ao----   4,00g                                                                     
  vm01-disk                       vg0 -wi-a----- 580,00g   
  vm01-swap                       vg0 -wi-a-----   8,00g

The nextcloud partition /dev/mapper/vg0-nextcloud is only visible inside the Dom0 VM. How do I expose the nextcloud partition to vm01 so I can use it as storage for Nextcloud there? I want to use the folder /var/www/nextcloud/html/data to be located on vg0-nextcloud.