htc incredible s s710內建儲存與sdcard互換

各位先拜大家好，小弟手機是 HTC Incredible S s710已經root
因內部儲存空間太小想要與sdcard互換但爬文後還是找不到跟我一樣內容的
我要修改etc/system/vold.fstab的內容想請問該如何修改?
我的手機vold.fstab內容如下改怎麼改謝謝
## Vold 2.0 fstab for HTC Passion
#
## - San Mehat ([email protected])
##

#######################
## Regular device mount
##
## Format: dev_mount <label> <mount_point> <part> <sysfs_path1...>
## label        - Label for the volume
## mount_point  - Where the volume will be mounted
## part         - Partition # (1 based), or "auto" for first usable partition.
## <sysfs_path> - List of sysfs paths to source devices
######################

# Mounts the first usable partition of the specified device
dev_mount sdcard /mnt/sdcard auto /devices/platform/goldfish_mmc.0 /devices/platform/msm_sdcc.4/mmc_host/mmc2