linux-kernel - Re: [PATCH 4/4] virtio_blk: use disk_name_format() to support mass of disks naming

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 2 Apr 2012 10:15:31 +0300
From:	"Michael S. Tsirkin" <mst@...hat.com>
To:	Tejun Heo <tj@...nel.org>
Cc:	Ren Mingxin <renmx@...fujitsu.com>, Jens Axboe <axboe@...nel.dk>,
	Rusty Russell <rusty@...tcorp.com.au>,
	LKML <linux-kernel@...r.kernel.org>,
	SCSI <linux-scsi@...r.kernel.org>, KVM <kvm@...r.kernel.org>,
	VIRTUAL <virtualization@...ts.linux-foundation.org>
Subject: Re: [PATCH 4/4] virtio_blk: use disk_name_format() to support mass
 of disks naming

On Fri, Mar 30, 2012 at 08:26:06AM -0700, Tejun Heo wrote:
> On Fri, Mar 30, 2012 at 05:53:52PM +0800, Ren Mingxin wrote:
> >  The current virtblk's naming algorithm only supports 263  disks.
> > If there are mass of virtblks(exceeding 263), there will be disks
> > with the same name.
> > 
> > By renaming "sd_format_disk_name()" to "disk_name_format()"
> > and moving it into block core, virtio_blk can use this function to
> > support mass of disks.
> > 
> > Signed-off-by: Ren Mingxin <renmx@...fujitsu.com>
> 
> I guess it's already way too late but why couldn't they have been
> named vdD-P where both D and P are integers denoting disk number and
> partition number?

Yes they could and yes it's way too late to change device
names for virtio - if we did this will break countless setups.

>  [sh]dX's were created when there weren't supposed
> to be too many disks, so we had to come up with the horrible alphabet
> based numbering scheme but vd is new enough.  I mean, naming is one
> thing but who wants to figure out which sequence is or guess what
> comes next vdzz9?  :(
> 
> If we're gonna move it to block layer, let's add big blinking red
> comment saying "don't ever use it for any new driver".
> 
> Thanks.

Right. virtio would have to use the legacy one though.

> -- 
> tejun
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/