[PATCH v3] xfs: probe data buffer from page cache for unwritten extents

[Mark Tinguely]

On 07/03/12 02:15, Jeff Liu wrote:
> Hello,
>
> This is v3 of the patch.
>
> We can trigger BUG() in xfs_seek_data() if met two unwritten without data or hole extents at last version.
> So making the extents map reading in loop could solve it.
>
> Sorry, Am not yet try the repeated holes scenario according to Dave's comments as lack of X64 test env, still
> waiting for it ready.  But this patch is already too long delayed, I have worked it out one weeks ago.
> So I'd like to post it because of it could handle repeated hole/unwritten extents well in a loop, and I also improved
> xfstests:286 with those cases for the verification, will post it soon.
>
> v2->v3:
> Tested by Mark, hit BUG() for continuous unwritten extents without data wrote.
> * xfs_seek_data(), remove BUG() and having extents map search in loop.
>
> v1->v2:
> suggested by Mark.
> * xfs_has_unwritten_buffer(), use the input offset instead of bmap->br_startoff to
>   calculate page index for data buffer probing.
>
> Thanks,
> -Jeff
>
>
> Signed-off-by: Jie Liu<jeff.liu at oracle.com>
>
> ---

Nice. Up to refining xfs_seek_hole()?


Reviewed-by: Mark Tinguely <tinguely at sgi.com>