[LG Optimus 4X HD] SimonTS:
Im not a developer. Wouldn't it work to do a

cat /proc/mounts
cat /proc/partitions
cat \proc/self/mountinfo

on the device to get the information you need?

Here's the output from my phone running Magic v2

2|u0_a104@android:/proc $ cat mounts
rootfs / rootfs ro,relatime 0 0
tmpfs /dev tmpfs rw,nosuid,relatime,mode=755 0 0
devpts /dev/pts devpts rw,relatime,mode=600 0 0
proc /proc proc rw,relatime 0 0
sysfs /sys sysfs rw,relatime 0 0
debugfs /sys/kernel/debug debugfs rw,relatime 0 0
none /acct cgroup rw,relatime,cpuacct 0 0
tmpfs /mnt/asec tmpfs rw,relatime,mode=755,gid=1000 0 0
tmpfs /mnt/obb tmpfs rw,relatime,mode=755,gid=1000 0 0
none /dev/cpuctl cgroup rw,relatime,cpu 0 0
/dev/block/platform/sdhci-tegra.3/by-name/APP /system ext4 ro,relatime,user_xattr,acl,barrier=0,data=ordered 0 0
/dev/block/platform/sdhci-tegra.3/by-name/UDA /data ext4 rw,nosuid,nodev,noatime,resuid=1000,errors=continue,user_xattr,acl,barrier=0,nodelalloc,nomblk_io_submit,data=ordered,noauto_da_alloc 0 0
/dev/block/platform/sdhci-tegra.3/by-name/CAC /cache ext4 ro,nosuid,nodev,noatime,user_xattr,acl,barrier=0,nomblk_io_submit,data=ordered,noauto_da_alloc 0 0
/dev/block/platform/sdhci-tegra.3/by-name/CAL /cal ext4 rw,nosuid,nodev,relatime,user_xattr,acl,barrier=0,data=ordered 0 0
/dev/block/platform/sdhci-tegra.3/by-name/DRM /persist-lg ext4 rw,nosuid,nodev,relatime,user_xattr,acl,barrier=0,data=ordered 0 0
/dev/block/platform/sdhci-tegra.3/by-name/MLT /mpt ext4 rw,nosuid,nodev,relatime,user_xattr,acl,barrier=0,data=ordered 0 0
/dev/fuse /storage/sdcard0 fuse rw,nosuid,nodev,relatime,user_id=1023,group_id=1023,default_permissions,allow_other 0 0
/dev/block/dm-0 /mnt/asec/com.asksven.betterbatterystats-1 ext4 ro,dirsync,nosuid,nodev,noatime,user_xattr,acl,barrier=1 0 0
/dev/block/dm-1 /mnt/asec/radiotime.player-1 ext4 ro,dirsync,nosuid,nodev,noatime,user_xattr,acl,barrier=1 0 0
/dev/block/dm-2 /mnt/asec/eu.chainfire.perfmon-1 ext4 ro,dirsync,nosuid,nodev,noatime,user_xattr,acl,barrier=1 0 0
/dev/block/dm-3 /mnt/asec/com.ttxapps.dropsync.pro-1 ext4 ro,dirsync,nosuid,nodev,noatime,user_xattr,acl,barrier=1 0 0
/dev/block/dm-4 /mnt/asec/com.quoord.tapatalkpro.activity-1 ext4 ro,dirsync,nosuid,nodev,noatime,user_xattr,acl,barrier=1 0 0
/dev/block/dm-5 /mnt/asec/com.teslacoilsw.launcher.prime-1 ext4 ro,dirsync,nosuid,nodev,noatime,user_xattr,acl,barrier=1 0 0
/dev/block/dm-6 /mnt/asec/com.joeykrim.rootcheckp-1 ext4 ro,dirsync,nosuid,nodev,noatime,user_xattr,acl,barrier=1 0 0
/dev/block/dm-7 /mnt/asec/cloudtv.hdwidgets-1 ext4 ro,dirsync,nosuid,nodev,noatime,user_xattr,acl,barrier=1 0 0
/dev/block/dm-8 /mnt/asec/com.enterprisingapps.android.enterpriseping-1 ext4 ro,dirsync,nosuid,nodev,noatime,user_xattr,acl,barrier=1 0 0
/dev/block/dm-9 /mnt/asec/com.riteshsahu.SMSBackupRestorePro-1 ext4 ro,dirsync,nosuid,nodev,noatime,user_xattr,acl,barrier=1 0 0
/dev/block/dm-10 /mnt/asec/com.quoord.tapatalkHD-1 ext4 ro,dirsync,nosuid,nodev,noatime,user_xattr,acl,barrier=1 0 0
/dev/block/vold/179:49 /storage/external_SD vfat rw,dirsync,nosuid,nodev,noexec,relatime,uid=1000,gid=1015,fmask=0002,dmask=0002,allow_utime=0020,codepage=cp437,iocharset=iso8859-1,shortname=mixed,utf8,errors=remount-ro 0 0

u0_a104@android:/proc $ cat partitions
major minor #blocks name

7 0 5229 loop0
7 1 16664 loop1
7 2 2111 loop2
7 3 2111 loop3
7 4 9387 loop4
7 5 2111 loop5
7 6 2111 loop6
7 7 42651 loop7
179 0 15267840 mmcblk0
179 1 10240 mmcblk0p1
179 2 10240 mmcblk0p2
179 3 1572864 mmcblk0p3
179 4 393216 mmcblk0p4
179 5 2048 mmcblk0p5
179 6 81920 mmcblk0p6
179 7 2048 mmcblk0p7
179 8 13062144 mmcblk0p8
179 9 16384 mmcblk0p9
179 10 16384 mmcblk0p10
179 11 20480 mmcblk0p11
179 12 16384 mmcblk0p12
179 13 47104 mmcblk0p13
179 32 2048 mmcblk0boot1
179 16 2048 mmcblk0boot0
179 48 31166976 mmcblk1
179 49 31164416 mmcblk1p1
254 0 5229 dm-0
254 1 16663 dm-1
254 2 2110 dm-2
254 3 2110 dm-3
254 4 9387 dm-4
254 5 2110 dm-5
254 6 2110 dm-6
254 7 42651 dm-7
7 8 2111 loop8
254 8 2110 dm-8
7 9 3150 loop9
254 9 3150 dm-9
7 10 20822 loop10
254 10 20821 dm-10

u0_a104@android:/proc/self $ cat mountinfo
1 1 0:1 / / ro,relatime - rootfs rootfs ro
11 1 0:11 / /dev rw,nosuid,relatime - tmpfs tmpfs rw,mode=755
12 11 0:9 / /dev/pts rw,relatime - devpts devpts rw,mode=600
13 1 0:3 / /proc rw,relatime - proc proc rw
14 1 0:12 / /sys rw,relatime - sysfs sysfs rw
15 14 0:5 / /sys/kernel/debug rw,relatime - debugfs debugfs rw
16 1 0:13 / /acct rw,relatime - cgroup none rw,cpuacct
17 1 0:14 / /mnt/asec rw,relatime - tmpfs tmpfs rw,mode=755,gid=1000
18 1 0:15 / /mnt/obb rw,relatime - tmpfs tmpfs rw,mode=755,gid=1000
19 11 0:16 / /dev/cpuctl rw,relatime - cgroup none rw,cpu
20 1 179:3 / /system ro,relatime - ext4 /dev/block/platform/sdhci-tegra.3/by-name/APP ro,user_xattr,acl,barrier=0,data=ordered
21 1 179:8 / /data rw,nosuid,nodev,noatime - ext4 /dev/block/platform/sdhci-tegra.3/by-name/UDA rw,resuid=1000,errors=continue,user_xattr,acl,barrier=0,nodelalloc,nomblk_io_submit,data=ordered,noauto_da_alloc
22 1 179:4 / /cache rw,nosuid,nodev,noatime - ext4 /dev/block/platform/sdhci-tegra.3/by-name/CAC ro,user_xattr,acl,barrier=0,nomblk_io_submit,data=ordered,noauto_da_alloc
23 1 179:12 / /cal rw,nosuid,nodev,relatime - ext4 /dev/block/platform/sdhci-tegra.3/by-name/CAL rw,user_xattr,acl,barrier=0,data=ordered
24 1 179:9 / /persist-lg rw,nosuid,nodev,relatime - ext4 /dev/block/platform/sdhci-tegra.3/by-name/DRM rw,user_xattr,acl,barrier=0,data=ordered
25 1 179:10 / /mpt rw,nosuid,nodev,relatime - ext4 /dev/block/platform/sdhci-tegra.3/by-name/MLT rw,user_xattr,acl,barrier=0,data=ordered
26 1 0:17 / /storage/sdcard0 rw,nos