Re: [Qemu-devel] qemu - SCSI disk "Device Model", "Serial Number", and "Firmware Version"?

[Markus Armbruster]

Dave Seddon <address@hidden> writes:

> Greetings,
>
> Just wondering if it would be difficult to add the ability to define the
> SCSI disk "Device Model", "Serial Number", and "Firmware Version".  I've
> been using the '-device lsi' successfully to emulate the LSI controller,
> but now I want to emulate certain disks too.
>
> e.g.  I've been using this:
> ---------------------------
> ...
>       -drive 
> if=none,id=disk00,file=/home/das/documents/qemu/disk00.img.qcow,media=disk,cache=writeback
>  \
>       -device lsi \
>       -device scsi-disk,drive=disk00,bus=scsi.0 \
> ...
> ---------------------------
>
>
> The reason this would be really cool is that tools like smartmontools
> seem to match on the "Device Model", and the device-model "QEMU" hasn't
> made it into the list yet.
>
> I found hunting around the net that somebody has tried to make this
> work.  I'm not sure if it works.
> '-drive ...,serial=xyz'
>
>
>
> This is how the QEMU disks are currently seen in dmesg:
> -------------------------------------------------------
> scsi 0:0:0:0: Direct-Access     QEMU     QEMU HARDDISK    0.12 PQ: 0
> ANSI: 3
>  target0:0:0: tagged command queuing enabled, command queue depth 16.
>  target0:0:0: Beginning Domain Validation
>  target0:0:0: Domain Validation skipping write tests
>  target0:0:0: Ending Domain Validation
> -------------------------------------------------------
>
> This is an example of a real disk, that I would like to 'fake':
> -------------------------------------------------------
> scsi 2:0:0:0: Direct-Access     ATA      ST3500320NS      SN06 PQ: 0 ANSI: 5
> sd 2:0:0:0: [sda] 976773168 512-byte hardware sectors (500108 MB)
> sd 2:0:0:0: [sda] Write Protect is off
> sd 2:0:0:0: [sda] Mode Sense: 73 00 00 08
> sd 2:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support 
> DPO or FUA
> sd 2:0:0:0: [sda] 976773168 512-byte hardware sectors (500108 MB)
> sd 2:0:0:0: [sda] Write Protect is off
> sd 2:0:0:0: [sda] Mode Sense: 73 00 00 08
> sd 2:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support 
> DPO or FUA
> -------------------------------------------------------
>
>
> Here's an example of the nasty/QEMU output of smartmontools:
> -------------------------------------------------------
> # smartctl -d sat --all /dev/sg0
> smartctl version 5.38 [i686-spcdn-linux-gnu] Copyright (C) 2002-8 Bruce Allen
> Home page is http://smartmontools.sourceforge.net/
>
> === START OF INFORMATION SECTION ===
> Device Model:     [No Information Found]
> Serial Number:    [No Information Found]
> Firmware Version: �"

That's not what I see.  What version of QEMU are you using?

> Device is:        Not in smartctl database [for details use: -P showall]
> ATA Version is:   1
> ATA Standard is:  Exact ATA specification draft version not indicated
> Local Time is:    Tue Jun  7 16:57:08 2011 UTC
> SMART is only available in ATA Version 3 Revision 3 or greater.
> We will try to proceed in spite of this.
> SMART support is: Ambiguous - ATA IDENTIFY DEVICE words 82-83 don't show if 
> SMART supported.
>                   Checking for SMART support by trying SMART ENABLE command.
>                   SMART ENABLE appeared to work!  Continuing.
> SMART support is: Ambiguous - ATA IDENTIFY DEVICE words 85-87 don't show if 
> SMART is enabled.
> A mandatory SMART command failed: exiting. To continue, add one or more '-T 
> permissive' options
> -------------------------------------------------------
>
>
> Here's an example of the output of smartmontools from a real disk:
> -------------------------------------------------------
> # smartctl -d sat --all /dev/sg1
> smartctl version 5.38 [i686-spcdn-linux-gnu] Copyright (C) 2002-8 Bruce
> Allen
> Home page is http://smartmontools.sourceforge.net/
>
> === START OF INFORMATION SECTION ===
> Device Model:     ST3500320NS     <--- CAN WE SIMULATE THIS?

No.  Hardcoded to "QEMU HARDDISK   ".

> Serial Number:    9QMCAMS6        <--- AND THIS?
> Firmware Version: SN06            <--- AND THIS?

Yes.  But -drive doesn't give you enough control.  You need to use
-device.  I'd point you to docs/qdev-device-use.txt for the details,
except it's outdated, and my patch to update it has been stuck on the
list for three weeks.  Need to repost.

Try

    -drive if=none,id=disk0,...
    -device scsi-hd,drive=disk0,serial=S,ver=V

> User Capacity:    500,107,862,016 bytes
> Device is:        Not in smartctl database [for details use: -P showall]
> ATA Version is:   8
> ATA Standard is:  ATA-8-ACS revision 4
> Local Time is:    Tue Jun  7 06:01:29 2011 UTC
> SMART support is: Available - device has SMART capability.
> SMART support is: Enabled
> -------------------------------------------------------
>
>
>
> Looking in the source, I can see that the "QEMU HARDDISK" for example is
> statically defined.  Would this be difficult to make an option for the
> '-drive '?

Doubt it would be difficult.  But would it be useful?  It's a bluff, and
if the guest calls it by using vendor-specific stuff, we'll surely fail,
won't we?

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