Debian – What Specifies the Version of cgroups (cgroups or cgroups2) Used by the Distro?

When you see the handlers like gphoto2:// and smb:// these are special interfaces that the GNOME desktop or whatever file browser you're using is making available to access these devices. In the case of gphoto2, the desktop is using the application gphoto2`

lsof

The only way I can think to gain access to a mount such as this would be to mount it as you did before using Nautilus or whatever file browser, and then using a tool such as lsof to see what files/devices are opened by Nautilus.

$ lsof -p $(pgrep nautilus)

But if you're having to connect to your phone via gphoto2 then you're likely not mounting the device a a mass storage device but rather a PTP - Picture Transfer Protocol. There's a Linux FUSE implementation for PTP too.

gvfs?

I would also look in your $HOME directory for a sub-directory called .gvfs. Usually when GNOME or Nautilus are doing the mounting this directory is created as a convenience.

In newer versions of GNOME (3+) this directory has moved and is now here, /run/user/$UID/gvfs.

Example

$ ls -l /run/user/$UID/gvfs/smb-share\:server\=tank\,share\=t 
total 2
drwx------. 1 saml saml    0 Oct 31 09:16 Development
drwx------. 1 saml saml    0 Nov 18 14:52 home
drwx------. 1 saml saml    0 May 14  2013 incoming
...

NOTE: That's a environment variable $UID that is often set in Bash on most modern systems. If it isn't set you can find your user's ID like so:

$ id
uid=1000(saml) gid=1000(saml) groups=1000(saml),10(wheel) context=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023

From the Kernel documentation titled: Network priority cgroup.

excerpt

net_prio.prioidx

This file is read-only, and is simply informative. It contains a unique integer value that the kernel uses as an internal representation of this cgroup.

net_prio.ifpriomap

This file contains a map of the priorities assigned to traffic originating from processes in this group and egressing the system on various interfaces. It contains a list of tuples in the form <ifname priority>. Contents of this file can be modified by echoing a string into the file using the same tuple format. for example:

   echo "eth0 5" > /sys/fs/cgroups/net_prio/iscsi/net_prio.ifpriomap

This command would force any traffic originating from processes belonging to the iscsi net_prio cgroup and egressing on interface eth0 to have the priority of said traffic set to the value 5. The parent accounting group also has a writeable 'net_prio.ifpriomap' file that can be used to set a system default priority.

I believe these priorities work where the higher the number, the higher the precedence. From the tc man page:

excerpt

   PRIO   The  PRIO  qdisc  is  a non-shaping container for a configurable 
          number of classes which are dequeued in order. This allows for 
          easy prioritization of traffic, where lower  classes  are
          only  able  to  send  if higher ones have no packets available. To 
          facilitate configuration, Type Of Service bits are honored by      
          default.

So if there are packets for a lower class they have to wait until there aren't any from a higher numbered class.

References

• 3.9. net_prio - Red Hat documentation portal