You are right. How to check flash size then?
Well, the easiest way to really do this is to type the ID at the top of the chip into a search engine.
This really matters if you run from there. (E.g. if it is installed to the internal memory with installtointernal script.)
This is my M8S (n200C), LE runs from the internal NAND:
Code: df -h
Filesystem Size Used Available Use% Mounted on
devtmpfs 766.4M 4.0K 766.4M 0% /dev
/dev/system 975.9M 124.1M 835.8M 13% /flash
/dev/loop0 122.0M 122.0M 0 100% /
/dev/data 5.3G 1.3G 3.9G 25% /storage
tmpfs 768.4M 0 768.4M 0% /dev/shm
tmpfs 768.4M 9.1M 759.2M 1% /run
tmpfs 768.4M 0 768.4M 0% /sys/fs/cgroup
tmpfs 768.4M 2.2M 766.2M 0% /var
tmpfs 768.4M 0 768.4M 0% /tmp