From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jan Beulich" <JBeulich@novell.com>
Subject: Re: [PATCH linux-2.6.18-xen] blktap: make max #
	of	 tap devices a module parameter
Date: Wed, 23 Feb 2011 09:42:23 +0000
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To: Laszlo Ersek <lersek@redhat.com>
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>>> 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.
>=20
> Oops, sorry; I naively assumed that minor device numbers were already=20
> covered by an earlier change.
>=20
> I figure register_chrdev() could be reimplemented in blktap, based on=20
> lower-level char_dev.c (and kobject) primitives, but I'm not sure if =
the=20
> original goal is worth that ugliness. In any case, should I bother=20
> posting a version like that eventually, or would it have no chance of=20
> being accepted?

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

Jan