list_sd_devices_on_usb_bus

What

A simple script to find the USB-attached SCSI disk devices (and list the USB device tree, too).

Where

This is meant to run on Linux. Tested so far on Fedora 17.

Why

This is an exercise in understanding how the Linux /sys tree and the USB device tree look like. I also wanted to be able to quickly check whether any of the /dev/sd* devices where currently being handled by something on the USB bus without grepping the kernel log.

Hence this script.

Problems and Bugs

None so far. Ready for general usage. But probably a bit too complicated.

See also

See also these utilities which should come with your distribution:

• lsusb(8) - list USB devices
• usbview(8) - USB topology and device viewer
• blkid(8) - locate/print block device attributes (command-line interface to working with the libblkid(3) library)
• The directory /dev/disk/by-path/ which helpfully lists the USB disks in the form or symlinks to device nodes
• lshw(1) - list hardware
• udisks(1) - simple command line client for the org.freedesktop.UDisks system bus service

As well as:

• http://www.linux-usb.org/FAQ.html
• http://www.kernel.org/doc/htmldocs/usb/API-struct-usb-device.html
• http://en.wikipedia.org/wiki/Sysfs
• http://en.wikipedia.org/wiki/Udev
• http://stackoverflow.com/questions/15830048/bash-search-for-usb-storage-devices-output-location
• http://stackoverflow.com/questions/13224509/linux-ubuntu-safely-remove-usb-flash-disk-via-command-line

Example output

In this example, the system has two harddisks branded "Intenso" hanging off USB bus #1.

Those devices have "vendor:product" id "152d:0539", which is actually the id of their JMicron controller.

Running lsusb -t from the command line yields the following:

/:  Bus 04.Port 1: Dev 1, Class=root_hub, Driver=ohci_hcd/5p, 12M
    |__ Port 1: Dev 2, If 0, Class=HID, Driver=usbhid, 1.5M
    |__ Port 2: Dev 3, If 0, Class=HID, Driver=usbhid, 12M
    |__ Port 2: Dev 3, If 1, Class=HID, Driver=usbhid, 12M
/:  Bus 03.Port 1: Dev 1, Class=root_hub, Driver=ohci_hcd/5p, 12M
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/5p, 480M
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/5p, 480M
    |__ Port 1: Dev 5, If 0, Class=stor., Driver=usb-storage, 480M
    |__ Port 2: Dev 6, If 0, Class=stor., Driver=usb-storage, 480M

and running lsusb without any option yields:

Bus 001 Device 005: ID 152d:0539 JMicron Technology Corp. / JMicron USA Technology Corp. 
Bus 001 Device 006: ID 152d:0539 JMicron Technology Corp. / JMicron USA Technology Corp. 
Bus 004 Device 002: ID 1050:0010 Yubico.com Yubikey
Bus 004 Device 003: ID 046d:c52e Logitech, Inc. 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub

Note that I have no idea where lsusb gets its "device 5 on bus 1" from.

Running the list_sd_devices_on_usb_bus.pl script yields something both harder to read and more informative, including the list of the devices partitions:

bus 1 -> port 0 -> config 1 -> interface 0 [1-0:1.0] [points to dir '/sys/devices/pci0000:00/0000:00:02.1/usb1/1-0:1.0']
bus 1 -> port 1 [1-1] [points to dir '/sys/devices/pci0000:00/0000:00:02.1/usb1/1-1']
     dev='189:4', product='External USB 3.0', id='152d:0539', version=' 2.10', manufacturer='Intenso', serial='201212010088'
bus 1 -> port 1 -> config 1 -> interface 0 [1-1:1.0] [points to dir '/sys/devices/pci0000:00/0000:00:02.1/usb1/1-1/1-1:1.0']
     Block device 'sdd' with device path '/sys/devices/pci0000:00/0000:00:02.1/usb1/1-1/1-1:1.0/host8/target8:0:0/8:0:0:0/block/sdd' matches this USB device path
          ...has partition 'sdd1' with size 10.00 MiB
          ...has partition 'sdd2' with size 931.50 GiB
bus 1 -> port 2 [1-2] [points to dir '/sys/devices/pci0000:00/0000:00:02.1/usb1/1-2']
     dev='189:5', product='External USB 3.0', id='152d:0539', version=' 2.10', manufacturer='Intenso', serial='201206140260'
bus 1 -> port 2 -> config 1 -> interface 0 [1-2:1.0] [points to dir '/sys/devices/pci0000:00/0000:00:02.1/usb1/1-2/1-2:1.0']
     Block device 'sde' with device path '/sys/devices/pci0000:00/0000:00:02.1/usb1/1-2/1-2:1.0/host9/target9:0:0/9:0:0:0/block/sde' matches this USB device path
          ...has partition 'sde1' with size 931.51 GiB
bus 2 -> port 0 -> config 1 -> interface 0 [2-0:1.0] [points to dir '/sys/devices/pci0000:00/0000:00:04.1/usb2/2-0:1.0']
bus 3 -> port 0 -> config 1 -> interface 0 [3-0:1.0] [points to dir '/sys/devices/pci0000:00/0000:00:02.0/usb3/3-0:1.0']
bus 4 -> port 0 -> config 1 -> interface 0 [4-0:1.0] [points to dir '/sys/devices/pci0000:00/0000:00:04.0/usb4/4-0:1.0']
bus 4 -> port 1 [4-1] [points to dir '/sys/devices/pci0000:00/0000:00:04.0/usb4/4-1']
     dev='189:385', product='Yubico Yubikey II', id='1050:0010', version=' 2.00', manufacturer='Yubico'
bus 4 -> port 1 -> config 1 -> interface 0 [4-1:1.0] [points to dir '/sys/devices/pci0000:00/0000:00:04.0/usb4/4-1/4-1:1.0']
bus 4 -> port 2 [4-2] [points to dir '/sys/devices/pci0000:00/0000:00:04.0/usb4/4-2']
     dev='189:386', product='USB Receiver', id='046d:c52e', version=' 2.00', manufacturer='Logitech'
bus 4 -> port 2 -> config 1 -> interface 0 [4-2:1.0] [points to dir '/sys/devices/pci0000:00/0000:00:04.0/usb4/4-2/4-2:1.0']
bus 4 -> port 2 -> config 1 -> interface 1 [4-2:1.1] [points to dir '/sys/devices/pci0000:00/0000:00:04.0/usb4/4-2/4-2:1.1']

License

Distributed under the MIT License, see http://opensource.org/licenses/MIT

Copyright (c) 2013
David Tonhofer
14, rue Aldringen
L-1118 Luxembourg

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.