submit_bio() flush to disk immediately

[Rajat Sharma]

On Tue, Aug 6, 2013 at 2:23 PM, Prashant Shah <pshah.mumbai at gmail.com> wrote:
> Hi,
>
>> Why do you want to modify blocks of a file, without filesystem knowing
>> about it? What are you trying to achieve here?
>>
>
> Its some shutdown - restart logic that I am working on :)
>
> I am sure doing it is not that complicated. I tried setting the page
> flags and marking it dirty. Even doing a sync doesnt work.

sync does not purge page-cache. I think you need to place some
filesystem hooks to purge-cache and make sure nobody else reads the
file while you update the block, because it will again populate
filesystem page-cache. Purging cache might be tricky.

> Regards.