From: Mike Snitzer <snitzer@redhat.com>
Date: Tue, 20 Aug 2013 19:02:41 +0000 (-0400)
Subject: dm cache: fix stacking of geometry limits
X-Git-Tag: v3.12-rc1~70^2~14
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f610937214e2ac8c4225df9a124ea0de1f030626;p=pandora-kernel.git

dm cache: fix stacking of geometry limits

Do not blindly override the queue limits (specifically io_min and
io_opt).  Allow traditional stacking of these limits if io_opt is a
factor of the cache's data block size.

Without this patch mkfs.xfs does not recognize the cache device's
provided limits as a useful geometry (e.g. raid) so these hints are
ignored.  This was due to setting io_min to a useless value.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
---

Reading git-diff-tree failed