Re: reiser4 metas/bmap problem

["Vladimir V. Saveliev" <vs@namesys.com>]

Hello

Christophe Saout wrote:
> Am Samstag, den 31.07.2004, 15:43 +0400 schrieb Vladimir V. Saveliev:
> 
> 
>>>>>>The ext3_bmap() function flushes all file data to disk when called, 
>>>>>>and it
>>>>>>would be prudent to do the same with reiser4, since bmap users tend 
>>>>>>to be
>>>>>>important and not speed critical (e.g. lilo) and failing to do so 
>>>>>>can mean
>>>>>>not booting later.
>>>>>>
>>>>>
>>>>>Interesting point.  vs, please comment.
>>>>>
>>>>
>>>>Yes, reiser4 might do something like that too. However, i am not sure 
>>>>how we can prevent relocation for files which were bmap-ed.
>>>>
>>>
>>>fsync first and then bmap?
>>
>>It file will be later overwritten - flush may decide to relocate it.
>>So, if application which bmapped it will not re-bmap - there will be a confusion.
> 
> 
> Are there any applications which write into a file and expect the blocks
> to stay at the same position?

I do not know

  In case of lilo you have to rerun lilo
> after writing a kernel because it might have changed in size. Usually
> the old kernel has been moved any and not been overwritten anyway. My
> personal opinion is that a filesystem sync (or implicit flusing when
> bmap is called) should be enough.
> 
yes, we will change reiser4_bmap that way