Re: [PATCH 1/3] Add virtioblk_id tool to extract drive serial numbers

[Ryan Harper <ryanh@us.ibm.com>]

* Kay Sievers <kay.sievers@vrfy.org> [2010-06-14 03:55]:
> On Thu, Jun 10, 2010 at 21:16, Ryan Harper <ryanh@us.ibm.com> wrote:
> > Use the 'VBID' virtio-blk ioctl to extract drive serial numbers
> > to be used for building disk/by-id symlinks.  After extracting
> > the serial number of the device it prints out the minimum info
> > needed in a similar format to `scsi_id --export` so that the
> > persistent-storage rules can process the serial information.
> >
> > This program depends on the virtio-blk serial device patches posted
> > here[1] being applied to qemu and linux-kernel.
> >
> > Here is what the output looks like:
> >
> > % ./virtioblk_id /dev/vdb
> > ID_VIRTIO=1
> > ID_TYPE=disk
> > ID_SERIAL=QM00001
> > ID_SERIAL_SHORT=QM00001
> 
> As requested in the ealier mail. Please provide a good reason why the
> kernel code can not create a "serial" file (or whatever fits your
> needs) in sysfs at the block device.

I didn't see you respond John's email:

http://www.spinics.net/lists/hotplug/msg03869.html

which included quite  bit of the gory history on this topic.

> 
> Other subsystems are doing the same thing like:
>   http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=blob;f=drivers/mmc/core/mmc.c;h‰f7a25b7ac12ab17f7baa9a18e0d980fe1c50eb;hb=HEAD#l270
> 
> We don't like to accumulate special purpose tools based on rather
> weird ioctls for newly developed stuff, which can be replaced with a
> few obviously and generally useful lines of code in the kernel driver.
> 
> As I think the general direction of solving the problem you describe
> is fundamentally wrong, I'll apply this only, if there are valid
> reasons not to add this to sysfs.
> 
> Thanks,
> Kay

-- 
Ryan Harper
Software Engineer; Linux Technology Center
IBM Corp., Austin, Tx
ryanh@us.ibm.com