Increase by 1GB

lvextend -L +1G /dev/centos/home

Decrease by 1GB

lvreduce -L 1G /dev/centos/var

For ext3 & ext4

resize2fs /dev/centos/home

For xfs

xfs_growfs /dev/centos/home

kpartx -av /dev/volKVM/kvm106_img
mount /dev/mapper/volKVM-kvm106_img1 /mnt

umount /mnt
kpartx -dv /dev/volKVM/kvm106_img