Re: [Qemu-devel] [PATCH 0/4] megaraid_sas HBA emulation

[Gerd Hoffmann <kraxel@redhat.com>]

On 10/30/09 09:12, Hannes Reinecke wrote:
> Gerd Hoffmann wrote:
>> http://repo.or.cz/w/qemu/kraxel.git?a=shortlog;h=refs/heads/scsi.v1
>>
>> It is far from being completed, will continue tomorrow.  Should give a
>> idea of the direction I'm heading to though.  Comments welcome.
>>
> Yep, this looks good.

More bits available now at:

http://repo.or.cz/w/qemu/kraxel.git/shortlog/refs/heads/scsi.v3

Please have a look at the new interface, this commit:

http://repo.or.cz/w/qemu/kraxel.git/commitdiff/9c825dac540282dd4d5f5f660ca13af617888037

The workflow I have in mind is:

   ->request_new()

Returns a parsed request, i.e. all fields of req->cmd are filled 
already, so the host adapter can easily check whenever it is a read or 
write and how many bytes will be transfered.

   ->request_run()

Execute the command.  iovec is passed to the dma_bdrv_*() functions, 
which means it should contain guest physical addresses.

When the request is done the complete callback is called.  For commands 
which complete immediately the callback might be called before 
request_run() returns.  Or maybe don't call the callback at all then? 
We can easily indicate using the return value that we are done already.

   ->request_del()

Release request when done.

Questions & comments are welcome.

cheers,
   Gerd