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

On Mon, Apr 02, 2012 at 09:19:05AM +0800, Ren Mingxin wrote:

 On 03/30/2012 11:28 PM, Tejun Heo wrote:

quoted

On Fri, Mar 30, 2012 at 08:26:06AM -0700, Tejun Heo wrote:

quoted

On Fri, Mar 30, 2012 at 05:53:52PM +0800, Ren Mingxin wrote:

quoted

 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<redacted>

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?  [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".

And also let's make that clear in the function name - say,
format_legacy_disk_name() or something.

So, to legacy disks [sh]d, we'd name them as [sh]d[a-z]{1,}. To new devices
like vd, we'd name them as vd<index>(vd<index>p<partno> as partitions)?

Pleae don't rename virtio disks, it is way too late for that:
virtio block driver was merged around 2007, it is not new by
any measure, and there are many systems out there using
the current naming scheme.

And how about the rssd in the patch 3 then?

Probably same. Renaming existing devices will break setups.
I think the idea is to avoid using the
legacy naming in new drivers *that will be added from now on*.

Besides, does anybody have comments?
Looking forward to your replies ;-)

-- 
Thanks,
Ren