How to format f2fs?

In the past I've done this from the recovery shell. But TWRP 3.0.0.1 does not offer this option under advanced wipe ... From the adb shell while booted into Pure Nexus i see a make_f2fs binary ... but have never attempted to format partitions from the booted system ...

Code:

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1|root@bullhead:/ # make_f2fs                                                 

        F2FS-tools: mkfs.f2fs Ver: 1.4.0 (2014-10-18)

        Error: Device not specified

Usage: mkfs.f2fs [options] device [sectors]
[options]:
  -a heap-based allocation [default:1]
  -d debug level [default:0]
  -e [extension list] e.g. "mp3,gif,mov"
  -l label
  -o overprovision ratio [default:5]
  -s # of segments per section [default:1]
  -z # of sections per zone [default:1]
  -t 0: nodiscard, 1: discard [default:1]
sectors: number of sectors. [default: determined by device size]

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Code:

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1|root@bullhead:/ # mount
rootfs / rootfs ro,seclabel 0 0
tmpfs /dev tmpfs rw,seclabel,nosuid,relatime,size=919280k,nr_inodes=229820,mode=755 0 0
devpts /dev/pts devpts rw,seclabel,relatime,mode=600 0 0
none /dev/cpuctl cgroup rw,relatime,cpu 0 0
none /dev/cpuset cgroup rw,relatime,cpuset,noprefix,release_agent=/sbin/cpuset_release_agent 0 0
adb /dev/usb-ffs/adb functionfs rw,relatime 0 0
proc /proc proc rw,relatime 0 0
sysfs /sys sysfs rw,seclabel,relatime 0 0
selinuxfs /sys/fs/selinux selinuxfs rw,relatime 0 0
/sys/kernel/debug /sys/kernel/debug debugfs rw,seclabel,relatime 0 0
none /sys/fs/cgroup tmpfs rw,seclabel,relatime,size=919280k,nr_inodes=229820,mode=750,gid=1000 0 0
pstore /sys/fs/pstore pstore rw,seclabel,relatime 0 0
none /acct cgroup rw,relatime,cpuacct 0 0
tmpfs /mnt tmpfs rw,seclabel,relatime,size=919280k,nr_inodes=229820,mode=755,gid=1000 0 0
/dev/fuse /mnt/runtime/default/emulated fuse rw,nosuid,nodev,noexec,noatime,user_id=1023,group_id=1023,default_permissions,allow_other 0 0
/dev/fuse /mnt/runtime/read/emulated fuse rw,nosuid,nodev,noexec,noatime,user_id=1023,group_id=1023,default_permissions,allow_other 0 0
/dev/fuse /mnt/runtime/write/emulated fuse rw,nosuid,nodev,noexec,noatime,user_id=1023,group_id=1023,default_permissions,allow_other 0 0
/dev/block/platform/soc.0/f9824900.sdhci/by-name/system /system ext4 ro,seclabel,relatime,data=ordered 0 0
/dev/block/platform/soc.0/f9824900.sdhci/by-name/vendor /vendor ext4 ro,seclabel,relatime,data=ordered 0 0
/dev/block/platform/soc.0/f9824900.sdhci/by-name/userdata /data ext4 rw,seclabel,nosuid,nodev,noatime,noauto_da_alloc,errors=panic,data=ordered 0 0
/dev/block/platform/soc.0/f9824900.sdhci/by-name/cache /cache ext4 rw,seclabel,nosuid,nodev,noatime,noauto_da_alloc,errors=panic,data=ordered 0 0
/dev/block/platform/soc.0/f9824900.sdhci/by-name/persist /persist ext4 rw,seclabel,nosuid,nodev,relatime,nodelalloc,errors=panic,data=ordered 0 0
/dev/block/platform/soc.0/f9824900.sdhci/by-name/modem /firmware vfat ro,context=u:object_r:firmware_file:s0,relatime,uid=1000,gid=1000,fmask=0337,dmask=0227,codepage=437,iocharset=iso8859-1,shortname=lower,errors=remount-ro 0 0
tmpfs /storage tmpfs rw,seclabel,relatime,size=919280k,nr_inodes=229820,mode=755,gid=1000 0 0
/dev/fuse /storage/emulated fuse rw,nosuid,nodev,noexec,noatime,user_id=1023,group_id=1023,default_permissions,allow_other 0 0

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