How to increase disk size without losing data?

So let's say I have /dev/sda with 100GB. I parted /dev/sda1 for / for 20GB. Now it's full. How can I re-size /dev/sda1 to 40GB while retaining the data?

df -kh

Filesystem Size Used Avail Use% Mounted on /dev/mapper/centos_wip--test-root 18G 18G 1.2M 100% / # lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sr0 11:0 1 1024M 0 rom sda 252:0 0 100G 0 disk\ └─sda1 252:2 0 19.5G 0 part ├─centos_wip--test-swap 253:254 0 2G 0 lvm [SWAP] └─centos_wip--test-root 253:255 0 17.5G 0 lvm / 

Thanks