[OnePlus 3 ROMs, Kernels, Recoveries, & Other Devel] Signor Rossi:
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shell@OnePlus3:/ $ cat /proc/partitions
major minor #blocks name

7 0 32768 loop0
8 0 56582144 sda
8 1 8 sda1
8 2 32768 sda2
8 3 262144 sda3
8 4 1024 sda4
8 5 512 sda5
8 6 128 sda6
8 7 128 sda7
8 8 512 sda8
8 9 10240 sda9
8 10 10240 sda10
8 11 1024 sda11
8 12 8096 sda12
8 13 16192 sda13
8 14 512 sda14
8 15 56238572 sda15
8 16 4096 sdb
8 17 4052 sdb1
8 32 4096 sdc
8 33 4052 sdc1
8 80 1572864 sdf
8 81 2048 sdf1
8 82 2048 sdf2
8 83 4 sdf3
8 84 512 sdf4
8 64 4194304 sde
8 65 512 sde1
8 66 512 sde2
8 67 2048 sde3
8 68 2048 sde4
8 69 512 sde5
8 70 512 sde6
8 71 2048 sde7
8 72 16 sde8
8 73 512 sde9
8 74 512 sde10
8 75 97280 sde11
8 76 16384 sde12
8 77 1024 sde13
8 78 32768 sde14
8 79 8192 sde15
259 0 8192 sde16
259 1 16384 sde17
259 2 65536 sde18
259 3 65536 sde19
259 4 3080192 sde20
259 5 65536 sde21
259 6 4 sde22
259 7 1024 sde23
259 8 512 sde24
259 9 512 sde25
259 10 256 sde26
259 11 256 sde27
259 12 256 sde28
259 13 256 sde29
259 14 256 sde30
259 15 256 sde31
259 16 4 sde32
259 17 33424 sde33
259 18 2048 sde34
8 48 131072 sdd
8 49 32 sdd1
8 50 4 sdd2
8 51 1024 sdd3
254 0 56238556 dm-0
shell@OnePlus3:/ $

shell@OnePlus3:/ $ mount
rootfs / rootfs ro,seclabel,size=2846160k,nr_inodes=711540 0 0
tmpfs /dev tmpfs rw,seclabel,nosuid,relatime,size=2921120k,nr_inodes=730280,mode=755 0 0
devpts /dev/pts devpts rw,seclabel,relatime,mode=600 0 0
proc /proc proc rw,relatime 0 0
sysfs /sys sysfs rw,seclabel,relatime 0 0
selinuxfs /sys/fs/selinux selinuxfs rw,relatime 0 0
debugfs /sys/kernel/debug debugfs rw,seclabel,relatime 0 0
none /acct cgroup rw,relatime,cpuacct 0 0
none /sys/fs/cgroup tmpfs rw,seclabel,relatime,size=2921120k,nr_inodes=730280,mode=750,gid=1000 0 0
tmpfs /mnt tmpfs rw,seclabel,relatime,size=2921120k,nr_inodes=730280,mode=755,gid=1000 0 0
none /dev/cpuctl cgroup rw,relatime,cpu 0 0
pstore /sys/fs/pstore pstore rw,seclabel,relatime 0 0
adb /dev/usb-ffs/adb functionfs rw,relatime 0 0
/dev/block/bootdevice/by-name/system /system ext4 ro,seclabel,noatime,discard,data=ordered 0 0
/dev/block/bootdevice/by-name/cache /cache ext4 rw,seclabel,nosuid,nodev,relatime,data=ordered 0 0
/dev/block/bootdevice/by-name/persist /persist ext4 rw,seclabel,nosuid,nodev,relatime,data=ordered 0 0
/dev/block/bootdevice/by-name/dsp /dsp ext4 ro,seclabel,nosuid,nodev,relatime,data=ordered 0 0
/dev/block/bootdevice/by-name/modem /firmware vfat ro,context=u:object_r:firmware_file:s0,relatime,uid=1000,gid=1000,fmask=0337,dmask=0227,codepage=437,iocharset=iso8859-1,shortname=lower,errors=remount-ro 0 0
/dev/block/bootdevice/by-name/bluetooth /bt_firmware vfat ro,context=u:object_r:bt_firmware_file:s0,relatime,uid=1002,gid=3002,fmask=0333,dmask=0222,codepage=437,iocharset=iso8859-1,shortname=lower,errors=remount-ro 0 0
tmpfs /storage tmpfs rw,seclabel,relatime,size=2921120k,nr_inodes=730280,mode=755,gid=1000 0 0
/dev/block/dm-0 /data ext4 rw,seclabel,nosuid,nodev,relatime,discard,noauto_da_alloc,data=ordered 0 0
/dev/block/loop0 /su ext4 rw,seclabel,noatime,data=ordered 0 0
/dev/fuse /mnt/runtime/default/emulated fuse rw,nosuid,nodev,noexec,noatime,user_id=1023,group_id=1023,default_permissions,allow_other,reserved_mem=50MB 0 0
/dev/fuse /storage/emulated fuse rw,nosuid,nodev,noexec,noatime,user_id=1023,group_id=1023,default_permissions,allow_other,reserved_mem=50MB 0 0
/dev/fuse /mnt/runtime/read/emulated fuse rw,nosuid,nodev,noexec,noatime,user_id=1023,group_id=1023,default_permissions,allow_other,reserved_mem=50MB 0 0
/dev/fuse /mnt/runtime/write/emulated fuse rw,nosuid,nodev,noexec,noatime,user_id=1023,group_id=1023,default_permissions,allow_other,reserved_mem=50MB 0 0
shell@OnePlus3:/ $

root@OnePlus3:/ # df
Filesystem Size Used Free Blksize
/ 2.7G 4.8M 2.7G 4096
/dev 2.8G 124.0K 2.8G 4096
/sys/fs/cgroup 2.8G 12.0K 2.8G 4096
/mnt 2.8G 0.0K 2.8G 4096
/mnt/runtime/default/emulated 52.6G 22.8G 29.8G 4096
/mnt/runtime/read/emulated 52.6G 22.8G 29.8G 4096
/mnt/runtime/write/emulated 52.6G 22.8G 29.8G 4096
/system 2.8G 2.4G 417.4M 4096
/cache 248.0M 1.1M 246.9M 4096
/persist 27.5M 420.0K 27.1M 4096
/dsp 11.7M 4.1M 7.6M 4096
/firmware 95.0M 81.2M 13.8M 16384
/bt_firmware 1023.7M 112.0K 1023.6M 16384
/storage 2.8G 0.0K 2.8G 4096
/storage/emulated 52.6G 22.8G 29.8G 4096
/data 52.7G 22.8G 29.9G 4096
/su 27.5M 1004.0K 26.5M 4096
root@OnePlus3:/ #