Re: [RFC][PATCH] limit state change to SDEV_BLOCK devices in scsi_internal_device_unblock

[Takahiro Yasui <tyasui@redhat.com>]

Matthew Wilcox wrote:
> On Mon, Apr 27, 2009 at 07:52:57PM -0400, Takahiro Yasui wrote:
>> James Bottomley wrote:
>>>> +	if (sdev->sdev_state != SDEV_BLOCK)
>>> This isn't quite correct.  There are two blocked states in the model
>>> currently:  SDEV_BLOCK and SDEV_CREATED_BLOCK ... you'd need to check
>>> for both of them
>>>
>>>> +		return 0;
>>> Traditionally the return for an attempted invalid state transition is
>>> -EINVAL.
>>>
>>> I suppose for lower down, if you check the state, now we know we go 
>>>
>>> SDEV_CREATED_BLOCK -> SDEV_CREATED
>>>
>>> or
>>>
>>> SDEV_BLOCK -> SDEV_RUNNING
>>>
>>> so there's no need for the dual scsi_device_set_state.
>> Thank you for the comments. If I understand your comments correctly, 
>> the state transition is better to be defined in scsi_device_set_state(),
>> and both transitions, "SDEV_CREATED_BLOCK -> SDEV_CREATED" and
>> "SDEV_BLOCK -> SDEV_RUNNING" need to be covered. I updated the patch
>> so that the transition of "SDEV_OFFLINE -> SDEV_RUNNING" is prohibited.
> 
> I don't think that's what he meant.  I think he meant something more like:

Thanks a lot. I'll build a patch and send it.

Regards,
---
Takahiro Yasui
Hitachi Computer Products (America), Inc.