Originally Posted by lantern

Yes, but partitioning has been done from recovery.

This is for POWER users with F5122! Normal users shouldn't do it!
You should transfer https://iwf1.com/iwf-repo/parted.rar tool onto phone, chmod +x it and then do:
1) ./parted /dev/mmcblk0
2) print
here you see

Code:

...#     start    end     size
51      1195MB  54.7GB  53.5GB               userdata
52      54.7GB  62.5GB  7843MB  ext4         system

3) you want to make system smaller (on stock SF it is 1.5GB), and make userdata bigger
4) rm 52
5) rm 51
this deletes both last partitions
6) mkpart
here you create userdata again, set up 'start' the same - 1195MB, but end - bigger (61.0GB)
7) mkpart
here you create system again, set up 'start' as the end of NEW userdata - 61.0GB, and end as before - 62.5GB
8) name 51
say 'userdata'
9) name 52
say 'system'


So now you will have

Code:

...
51      1195MB  61.0GB  59.8GB               userdata
52      61.0GB  62.5GB  1537MB               system