rbd: support reading parent page data
authorAlex Elder <elder@inktank.com>
Mon, 6 May 2013 22:40:33 +0000 (17:40 -0500)
committerAlex Elder <elder@inktank.com>
Thu, 9 May 2013 01:16:25 +0000 (20:16 -0500)
commit5b2ab72d367d2682c1a237448fbc1595881a88fa
tree8a5e066888a1847fe9f22f1be6ced3a0ff90ef32
parent91c6febb3817be576785ef06aeaaa8ed423e0a2a
rbd: support reading parent page data

Currently, rbd_img_parent_read() assumes the incoming object request
contains bio data.  But if a layered image is part of a multi-layer
stack of images it will result in read requests of page data to parent
images.

Fortunately, it's not hard to add support for page data.

This resolves:
    http://tracker.ceph.com/issues/4939

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
drivers/block/rbd.c