Re: [RFC] SCSI target for IBM Power5 LPAR

[Mike Christie <michaelc@cs.wisc.edu>]

FUJITA Tomonori wrote:
> month. We discussed it with Christoph and decided that it would be
> better to start from scratch because of the design differences.

Some of the things we are trying to improve upon are things that are 
better supported in 2.6. Some differences:

- We will support controller hotplug.
- We allow any type of device (dm, scsi, ide, LVM@ etc) as storage. And 
we do not want hook into SCSI-ml's upper layer drivers and deal with 
that refcounting if we can help it so we push a lot of code to userspace 
and only do reads and writes in the kernel.
- We also hope to support any block layer target.
- As mentioned before, scatterlists by using the block layer's support.

There may be more that I am forgetting, but originally we started out by 
trying to clean up the SCST code for 2.6 and make it resemble SCSI-ml's 
hotplug model. As we did this it looked like some code could live in 
userspace and it would end up being a rewrite becuase there was so much 
to do so we started a new project. We hope to work with Vlad and the 
SCST developers.