[PATCH] vfs_streams_xattr: Do not attempt to write empty attributetwice

[Christof Schmitt]

On Fri, Jun 14, 2013 at 06:15:50AM -0700, Richard Sharpe wrote:
> For my part the change looks correct.

Good.

> However, the issue I have with storing streams in XATTRs is that each
> stream should act like a real file. That means that you could write
> one sector to offset 0 and another sector to offset 512. That semantic
> is hard to handle with XATTRs and the module the way it is.

Yes, that is a general limitation of this approach. The size of
streams is also limited by the size of xattrs on the underlying
filesystems. I am testing this approach to find out if it would be
sufficient for the small streams created by Windows clients like
favicon, zoneidentifier, etc.

The advantage of this approach is that the xattrs are tied to the file.
Even when the file is deleted directly on the filesystem, there is no
dangling streams file like in the streams_depot approach.

-- 
Christof Schmitt || IBM || SONAS System Development || Tucson, AZ
christof.schmitt at us.ibm.com  ||  +1-520-799-2469  (T/L: 321-2469)