OpenWRT Resize Squashfs Partition to Utilize all SD Card Space

Based on Openwer document here

Expanding the filesystem

To use the whole available space of your sdcard, you probably have to resize your partition.

squashfs image

To resize the squashfs-image one has to know the offset of the hidden f2fs filesystem. In this example, the squashfs partiton is /dev/sde2.

1. You can find the offset, by running losetup on your openwrt device.

2. Eject your SD card and place it on your computer with linux system, resize the squashfs partition, for example with cfdisk.

   sudo cfdisk /dev/sde

   • chose squashfs partition (which in this case is partition sde2)
   • specify the new size that you want to allocate to the partition
   • select write on that partition

   

3. Loop mount the underlying f2fs partition

   losetup -d -o <offset> /dev/loop0 /dev/sde2

   if its not working, use this instead

   losetup -f -o <offset> /dev/sde2
   # above command defaults to a loop device at /dev/loop0, 
   # I havent try on device that have more than one loop device

4. Run filesystem checks

   fsck.f2fs /dev/loop0

5. Resize f2fs filesystem

   resize.f2fs /dev/loop0

   Now insert your sd card to your openwrt device. Your filesystem should be recognized with the correct size.

ext4 image

You can us gparted to resize and extend the partitions. To do it online, follow the procedure in link or link.

mount -o remount,ro /                  #Remount root as Read Only
tune2fs -O^resize_inode /dev/device    #Remove reserved GDT blocks
fsck.ext4 /dev/device                  #Fix part, answer yes to remove GDT blocks remnants

#reboot
resize2fs /dev/device