lvm2_to_raw

# lvm_scan
Scanning devices  for LVM volume groups
Reading all physical volumes. This may take a while...
Found volume group "fedora" using metadata type lvm2
2 logical volume(s) in volume group "fedora" now active
# cat /proc/partitions
major minor  #blocks  name

 252        0    7340032 vda
 252        1     204800 vda1
 252        2    1048576 vda2
 252        3    6085632 vda3
 253        0     737280 dm-0
 253        1    5345280 dm-1
# dd if=/dev/dm-1 of=/dev/vda3 bs=$(((1<<21)-4))K
2+1 records in
2+1 records out
5473566720 bytes (5.5 GB, 5.1 GiB) copied, 18.9428 s, 289 MB/s