Re: xattr

[Hans Reiser <reiser@namesys.com>]

Chris Mason wrote:

>On Mon, 2003-06-16 at 08:26, Russell Coker wrote:
>  
>
>>What is the status of xattr support in 2.5.x?
>>
>>How is journalling of xattr's being handled?
>>
>>For correct operation of SE Linux we need to have the xattr that is used for 
>>the security context be changed atomically, and if a file is created and 
>>immediately has the xattr set then ideally we would have the file creation 
>>and the xattr creation in the same journal entry.
>>
>>Is this possible?  If doing this requires that the file system be mounted with 
>>data=journal then this will be fine.
>>    
>>
>
>How big are the xattrs you have in mind?  We can get atomic writes of 4k
>in length but beyond that things get more difficult.
>
it is complete trivial to do it in reiser4.

>
>As for the xattr and the create in the same transaction, that's a little
>harder.  
>
equally easy in reiser4.

>We'd probably need a new syscall, or to change the semantics of
>the xattr call such that creating an xattr on a file that doesn't exist
>also creates the file.
>
>-chris
>
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>  
>
V3 should not have new features added to it.  It needs to be zero 
defect, and avoiding new features is the only way.

-- 
Hans