WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

Re: [Xen-devel] Re: Help please: bug#625 SCSI disk conflicts with blkfro

Dan Smith wrote:

Is there another benefit to having a low-level SCSI driver that I'm
missing?~

For my own purposes, I'm planning on building a SCSI generic front- end/back-end driver pair to make SCSI disks available to domU's. This driver would be available to the Xen community.

Since I'm not running Linux on the front-end, I hadn't thought much about the major device number problem. Instead, I've got an O/S that generates SCSI requests and I didn't want to have to work very hard to try to translate them to blk requests: SES commands, test unit ready, serial number requests, etc. In addition, our O/S uses scatter/gather lists extensively and I'd like to pass those along instead of buffering and copying data.

I figured I'd just rely on the SCSI generic driver to send my already- generated requests over the SCSI adapter to the devices on the bus.

Since I've never written a Xen driver before, my basic premise was to begin with a basic front-end talking to a back-end and adding functional components one at a time. And, documenting my work for others to read. Or, is there already good documentation somewhere on designing/building a front-end/back-end driver pair?

-- Randy

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel