From: "Martin K. Petersen" <martin.petersen@oracle.com>
Subject: Re: [PATCH v2] dm: Fix alignment stacking on partitioned
	devices
Date: Tue, 05 Jan 2010 22:24:59 -0500
Message-ID: <yq11vi3ud84.fsf@sermon.lab.mkp.net>
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	<yq1637gt1hi.fsf@sermon.lab.mkp.net>
	<20100106025731.GA16154@redhat.com>
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>>>>> "Mike" == Mike Snitzer <snitzer@redhat.com> writes:

Mike,

Mike> After looking closer there seems to be various type
Mike> inconsistencies in the alignment_offset and discard_alignment
Mike> related routines (returning 'int' in places, etc).

Mike> The following patch is what I found; I have no problem with
Mike> switching from 'unsigned long' to blk_off_t for LBD though.

I only use blk_off_t in the places where we're dealing with absolute
offsets.

Blindly converting alignment_offset from int to unsigned long won't
work.  We depend on being able to return -1 in case of
misalignment. Hence int and not unsigned int. Furthermore, the returned
values are always modulo the granularity so int is plenty big.

So NAK from here.

-- 
Martin K. Petersen	Oracle Linux Engineering