That's what I was thinking. What is the filesystem layout in Sailfish?
[nemo@localhost /]$ cat /etc/fstab UUID=0f8a2480-53ed-5ff6-ba64-b81df3630387 / btrfs defaults,autodefrag,noatime 0 0 UUID=0f8a2480-53ed-5ff6-ba64-b81df3630387 /home btrfs subvol=@home 0 0 UUID=0f8a2480-53ed-5ff6-ba64-b81df3630387 /swap btrfs subvol=@swap 0 0 devpts /dev/pts devpts gid=5,mode=620 0 0 tmpfs /dev/shm tmpfs defaults 0 0 proc /proc proc defaults 0 0 sysfs /sys sysfs defaults 0 0
[nemo@localhost /]$ mount ... /dev/mmcblk0p19 on /drm type ext4 (rw,nosuid,nodev,relatime,data=ordered) /dev/mmcblk0p18 on /firmware type vfat (ro,relatime,uid=1000,gid=1000,fmask=0337,dmask=0227,codepage=cp437,iocharset=iso8859-1,shortname=lower,errors=remount-ro) /dev/mmcblk0p25 on /persist type ext4 (ro,nosuid,nodev,relatime,data=ordered) /dev/mmcblk0p9 on /var/systemlog type ext4 (rw,nosuid,nodev,relatime,data=ordered) /dev/mmcblk0p28 on /home type btrfs (rw,relatime,thread_pool=4,ssd,noacl,space_cache,autodefrag) /dev/mmcblk0p28 on /swap type btrfs (rw,relatime,thread_pool=4,ssd,noacl,space_cache,autodefrag) ...