umass -> da device mapping info

hi!

freebsd needs a umass -> da device mapping information.

what i mean is the following:

after inserting a usb memory stick (as example)
the devices pass0, da0 and da0s1 are created.

but how i find out what umass device is mapped
to the devices above?

i suggest a new sysctl variable:

dev.umass.0.%mappedto=da0

or better:

dev.da.0.%mappedfrom=umass0

or something like this.

currently the only command that "tells" me the umass
device is "camcontrol devlist -v": umass-sim0

everything i s easy if there is no existing daX device
and only one usb mass device is used but in every other
case it's very diffcult to write an automated script.

that information can also be very usefull in usbd.conf as
variable in the attach command not only ${DEVICE} which
in case of umassX didn't really exist.

franz.