Re: GEOM weirdness with SD flash reader?

On Sun, 1 Jul 2007, Nate Lawson wrote:

>> : I disagree.  Once scsi_da found the media, it would then somehow need to
>> : notify devd (i.e. to automount).  If both functions are in devd, the
>> : loop becomes:
>> :
>> : while (1) {
>> :     camcontrol tur mydev;
>> :     if (found)
>> :         notify_automount;
>> :         break;
>> :     sleep 3;
>> : }
>>
>> This doesn't belong in devd.
>>
>> Robert has patches to bring new geom entries into the realm of devd.
>
> URL?

This is from quite a long time ago, so likely needs massaging to apply.

   http://www.watson.org/~robert/freebsd/geom_devctl.diff

The idea is straight forward: when a new geom device is discovered, we issue a 
notification, which allows devd to respond to events above the newbus layer -- 
i.e., discover of an fdisk partition table, swap-backed md device, attachment 
of a new software RAID layer, arrival of a volume by volume name, arrival of a 
ZFS volume, etc.

A simultaneous discussion was going on regarding whether to notify about 
ifnets directly, and my feeling was basically that since software components 
care about the distinction between "em0" as a PCI device and "em" as a network 
interface, and likewise between "ad0" as a disk device" and "ad0s1a" as a 
partition.  The other perspective was that newbus should grow to encapsulate 
all these name spaces and services -- i.e., establish newbus nodes for md0, 
lo0, etc, and use some combination of the attachment name space and object 
types to handle this.  I don't really mind what the end solution is, but I 
found these patches quite useful locally :-).

Robert N M Watson
Computer Laboratory
University of Cambridge