Re: [Qemu-devel] [PATCH 1/2] Add 'serial' attribute to virtio-blk devices

[Christoph Hellwig <hch@lst.de>]

On Fri, Jun 18, 2010 at 01:38:02PM -0500, Ryan Harper wrote:
> Create a new attribute for virtio-blk devices that will fetch the serial number
> of the block device.  This attribute can be used by udev to create disk/by-id
> symlinks for devices that don't have a UUID (filesystem) associated with them.
> 
> ATA_IDENTIFY strings are special in that they can be up to 20 chars long
> and aren't required to be NULL-terminated.  The buffer is also zero-padded
> meaning that if the serial is 19 chars or less that we get a NULL terminated
> string.  When copying this value into a string buffer, we must be careful to
> copy up to the NULL (if it present) and only 20 if it is longer and not to
> attempt to NULL terminate; this isn't needed.

Why is this virtio-blk specific?  In a later mail you mention you want
to use it for udev.  So please export this from scsi/libata as well and
we have one proper interface that we can use for all devices.