[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH v3 01/12] block: Add op blocker type "device IO"
|
From: |
Fam Zheng |
|
Subject: |
Re: [Qemu-devel] [PATCH v3 01/12] block: Add op blocker type "device IO" |
|
Date: |
Fri, 15 May 2015 15:06:37 +0800 |
|
User-agent: |
Mutt/1.5.23 (2014-03-12) |
On Fri, 05/15 14:22, Wen Congyang wrote:
> On 05/15/2015 02:04 PM, Fam Zheng wrote:
> > It blocks device IO.
>
> I am reading mirror codes recently, and have a question:
> When block job mirror is finished, the source and target is synced. But we
> call bdrv_swap() later(in bh context). Can the guest write something to
> the source before the bh is scheduled? If the answer is yes, I think
> we should use this to block the guest's disk I/O.
I think you're right. After mirror_run returns, anything can happen on this aio
context, including guest writing.
Fam
- [Qemu-devel] [PATCH v3 00/12] Fix transactional snapshot with dataplane and NBD export, Fam Zheng, 2015/05/15
- [Qemu-devel] [PATCH v3 01/12] block: Add op blocker type "device IO", Fam Zheng, 2015/05/15
- [Qemu-devel] [PATCH v3 02/12] block: Add op blocker notifier list, Fam Zheng, 2015/05/15
- [Qemu-devel] [PATCH v3 03/12] block-backend: Add blk_op_blocker_add_notifier, Fam Zheng, 2015/05/15
- [Qemu-devel] [PATCH v3 06/12] nbd-server: Clear "can_read" when "device io" blocker is set, Fam Zheng, 2015/05/15
- [Qemu-devel] [PATCH v3 05/12] virtio-blk: Don't handle output when there is "device IO" op blocker, Fam Zheng, 2015/05/15