BTW, this workaroud only works for ROM based on Android 7.x (Nougat).
For Oreo-based MIUI (Android 8.x), the location of "fstab.qcom" has been moved to /system/vendor/etc/fstab.qcom. You need to modify that file accordingly, by changing "encryptable=ice" to "fileencryption=ice".
Edit: If you...