Re: [Qemu-devel] cdrom hardcoded index

[Paul Brook <paul@codesourcery.com>]

On Monday 28 August 2006 13:20, Armistead, Jason wrote:
> On Monday, 28 August 2006 10:08 PM (AEST) Míguel wrote:
> >> What about something like -hdX test.iso,hw=cdrom with default hw being
>
> disk?
>
> >And why not a shorted and more standard solution?
> >
> >-ideN [hd:|cd:]filename
>
> And what about non-PC guest environments like Sparcs where there are no IDE
> drives, only SCSI ones for hard disk, CD and (I think) for floppy drives ?
> How would you expand that syntax ?
>
> Not everyone running QEMU is seeking to run a "PC in PC" configurations.

If you' are changing these options you may as well make if possible to use 
scsi on x86 targets. All the device emulation is there (commented out in 
pc.c) it's just missing the user-visible options to turn it on.

My current thinking is that instead of a fixed set of block devices, the host 
device emulation (IDE controller, SCSI HBA) would register named device with 
qemu. Each adapter is given a name (ide0, scsi0, etc), and has numbered slots 
for attaching storage devices. Then use a commandline syntax similar to 
the -net options to connect disks. Something like:

-disk dev=ide0,id=0,file=foo.iso,type=cdrom -disk scsi0,3,bar.img

Gives you an ide cdrom on  primary master channel, and a scsi harddrive with 
SCSI ID3 on the scsi controller.

I guess we probably want to model a dual-channel IDE controller as two 
separate controllers for these purposes.

If done properly I'd expect this scheme to allow hot-plugging of devices, and 
automatic selection of the emulated hardware based on what devices the user 
requests. I'd also hope it would fit nicely into future config file 
structure.

Paul