Luca Tettamanti wrote:
On Mon, Oct 19, 2009 at 2:14 PM, Tomasz Chmielewski <man...@wpkg.org> wrote:
lspci implies that the virtio block device is a "SCSI storage controller",
i.e.:

00:05.0 SCSI storage controller: Qumranet, Inc. Virtio block device


However, virtio block devide does not have much to do with SCSI (in sense:
sdparm does not think it is a SCSI device; virtio_blk does not depend on any
SCSI moduled like sd_mod).

Is "SCSI storage controller" a proper description for this device?

It does not talk SCSI protocol if that's what you're asking. The
description you see comes from the PCI class (storage controller) and
subclass (SCSI controller); the meaning of the class/subclass is fixed
by the PCI standard.

So why was "SCSI storage controller" any better than "IDE interface" or "SATA controller" for virtio block device, if it does not talk SCSI protocol (other than "SCSI storage controller" being the first on the list of subclasses)?


Doesn't "80 Mass storage controller" ("0x80 0x00 Other mass storage controller") fit better for virtio block device?

Generally, I see that 0x80 is reserved for "other/unspecified" types of devices from a given PCI class.


Let me know if I'm asking a stupid question ;)



C 01  Mass storage controller
        00  SCSI storage controller
        01  IDE interface
        02  Floppy disk controller
        03  IPI bus controller
        04  RAID bus controller
        05  ATA controller
                20  ADMA single stepping
                30  ADMA continuous operation
        06  SATA controller
                00  Vendor specific
                01  AHCI 1.0
        07  Serial Attached SCSI controller
        80  Mass storage controller


--
Tomasz Chmielewski
http://wpkg.org
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to