Hi All,

We have 128 MB eMMC based NAND Flash which has squashfs based rootfs.
My device boots up and rootfs is mounted properly. I do not have any issue during booting.

# mount
rootfs on / type rootfs (rw)
/dev/root on / type squashfs (ro,relatime)
devtmpfs on /dev type devtmpfs (rw,relatime,size=124856k,nr_inodes=31214,mode=755)
proc on /proc type proc (rw,relatime)
devpts on /dev/pts type devpts (rw,relatime,gid=5,mode=620)

#cat /proc/cmdline
root=/dev/mmcblk0p12 rootwait ro console=ttyS0,115200n8

# df -h
Filesystem Size Used Available Use% Mounted on
/dev/root 7.8M 7.8M 0 100% /
devtmpfs 121.9M 4.0K 121.9M 0% /dev

#du -sh /
121.4 MB

Query :

1) Rootfs mounted in "/" directory and size of the Filesystem partition is 7.8 MB.

2) How does entire rootfs is 122 MB which is found using (du -sh / ) when /dev/root size 7.8M.

3) Does squashfs use virtual space while accessing I/O operation?

Please clarify my queries.


Thankx
Murali.S

It just means that much storage is reserved for rootfs.