Re: unregister_ioctl32_conversion and modules. ioctl32 revisited.

[Takashi Iwai]

At Wed, 15 Dec 2004 09:46:35 +0200,
Michael S. Tsirkin wrote:
> 
> There were two additional motivations for my patch:
> 1. Make it possible to avoid the BKL completely by writing
>    an ioctl with proper internal locking.
> 2. As noted by  Juergen Kreileder, the compat hash does not work
>    for ioctls that encode additional information in the command, like this:
> 
> #define EVIOCGBIT(ev,len)  _IOC(_IOC_READ, 'E', 0x20 + ev, len)

I like the idea very well.  Other benifits in addition:

3. Can avoid conflict of ioctls with the same value since the
   convertor is registered locally.

4. Can reject unsupported ioctls for the device (but may be valid for
   other devices) before converting the data - the same reason as
   above.

--
Takashi Iwai <tiwai@xxxxxxx>		ALSA Developer - www.alsa-project.org
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