|
From: | Paolo Bonzini |
Subject: | Re: [Qemu-devel] virtio scsi host draft specification, v2 |
Date: | Wed, 01 Jun 2011 18:25:02 +0200 |
User-agent: | Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.17) Gecko/20110428 Fedora/3.1.10-1.fc14 Lightning/1.0b3pre Mnenhy/0.8.3 Thunderbird/3.1.10 |
On 06/01/2011 03:46 PM, Avi Kivity wrote:
Virtqueues 0:control transmitq 1:control receiveq 2:requestqShouldn't we plan multiqueue for this from day 1?
How would you do multiqueue? Just provide N queues, and the device can place requests for any LUN on any queue?
If that's correct, it doesn't sound too hard to do, but also doesn't sound problematic to fit it later. So I'm quite ambivalent
Requests have the following format: struct virtio_scsi_req_cmd { u8 lun[8]; u64 id; u8 task_attr; u8 prio; u8 crn; u32 num_dataout, num_datain; char cdb[]; char data[][num_dataout+num_datain]; u8 sense[]; u32 sense_len; u32 residual; u16 status_qualifier; u8 status; u8 response; };flags? room for growth?
Feature bits can be used to negotiate the exact format of the request. I don't expect many changes, since we're closely mimicking the SCSI requests.
Paolo
[Prev in Thread] | Current Thread | [Next in Thread] |