Re: [PATCH] vhost-blk: Add vhost-blk support v2

[Asias He <asias@redhat.com>]

On 10/23/2012 08:07 AM, Rusty Russell wrote:
> "Michael S. Tsirkin" <mst@redhat.com> writes:
>> On Thu, Oct 18, 2012 at 02:50:56PM +1030, Rusty Russell wrote:
>>> Asias He <asias@redhat.com> writes:
>>>>>> +#define BLK_HDR	0
>>>>>
>>>>> What's this for, exactly? Please add a comment.
>>>>
>>>> The block headr is in the first and separate buffer.
>>>
>>> Please don't assume this!  We're trying to fix all the assumptions in
>>> qemu at the moment.
>>>
>>> vhost_net handles this correctly, taking bytes off the descriptor chain
>>> as required.
>>>
>>> Thanks,
>>> Rusty.
>>
>> BTW are we agreed on the spec update that makes cmd 32 bytes?
> 
> vhost-blk doesn't handle scsi requests, does it?

No, it doesn't handle scsi requests currently.

> 
> But since we're forced to use a feature bit, we could just put the cmd
> size in explicitly.  Though Paulo seems convinced that 32 is always
> sufficient.  Whoever implements it gets to decide...
> 
> Here's my TODO list:
> 1) Create qemu helpers to efficiently handle iovecs.
> 2) Switch all the qemu devices to use them.
> 3) ... except a special hack for virtio-blk in old-layout mode.
> 4) Implement pci capability layout RFC for qemu.
>    - Detect whether guest uses capabilities.
>    - Device config in new mode is le.
>    - Add strict checking mode for extra compliance checks?
> 5) Add explicit size-based accessors to virtio_config in kernel.
> 6) Update pci capability RFC patches for linux to match.
>    - Use explicit accessors to allow for endian conversion.
> 6) Push virtio torture patch to test variable boundaries.
> 7) Update spec.
> 
> That should keep me amused for a while...
> 
> Cheers,
> Rusty.
> 


-- 
Asias