Re: [PATCH linux-2.6.18-xen] blktap: make max # of tap devices a module parameter

["Jan Beulich" <JBeulich@novell.com>]

>>> On 22.02.11 at 18:34, Laszlo Ersek <lersek@redhat.com> wrote:
> On 02/22/11 16:49, Jan Beulich wrote:
>>>>> On 22.02.11 at 15:20, Laszlo Ersek<lersek@redhat.com>  wrote:
>>> Hi,
>>>
>>> should anybody still use the blktap(1) driver in linux-2.6.18-xen, the
>>> following patch intends to make the maximum number of tapdevs
>>> configurable at module insertion time. The number is clamped to [256 ..
>>> NR_EVENT_CHANNELS]. I removed the definition of MAX_DEV_NAME because it
>>> didn't seem to be used at all.
>>>
>>> Thanks for considering,
>>> Laszlo Ersek
>>
>> Without replacing the call to register_chrdev() with one to
>> __register_chrdev() (available only with 2.6.32 and newer) I
>> can't see how you would get beyond 256 devices with the
>> changes you propose.
> 
> Oops, sorry; I naively assumed that minor device numbers were already 
> covered by an earlier change.
> 
> I figure register_chrdev() could be reimplemented in blktap, based on 
> lower-level char_dev.c (and kobject) primitives, but I'm not sure if the 
> original goal is worth that ugliness. In any case, should I bother 
> posting a version like that eventually, or would it have no chance of 
> being accepted?

I too had thought about doing this in the past, but decided there#s
not much point in it.

Jan