Re: minor ID for btrfs-control

[Goffredo Baroncelli <kreijack@libero.it>]

Hello Helmut,

On 04/03/2011 05:11 AM, Helmut Hullen wrote:
> Hallo, Goffredo,
[..]
>> As wrote by Tomasz the minor number of the btrfs-control is allocated
>> dynamically.
> 
> At which place?

I replied you too fast. Btrfs register a "misc" device, but its number
is not dynamically allocated (see [1] for further information), but it
is static.

$ grep BTRFS_MINOR -r include/
include/linux/miscdevice.h:#define BTRFS_MINOR          234

I can conclude that _now_ the minor is 234 and not 55. But I don't know
if it is a _stable_ interface.

I think that during the boot you should check the minor with

grep btrfs-control /proc/misc | awk '{ print $1 }'


Regards
G.Baroncelli

[1] http://www.linuxjournal.com/article/2920

> 
> Viele Gruesse!
> Helmut
> --
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> .
>