From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jens Axboe <jens.axboe@oracle.com>
Subject: Re: [PATCH] DM data integrity support
Date: Fri, 24 Oct 2008 08:25:21 +0200
Message-ID: <20081024062519.GK22217@kernel.dk>
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To: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: device-mapper development <dm-devel@redhat.com>, Alasdair G Kergon <agk@redhat.com>
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On Fri, Oct 24 2008, Martin K. Petersen wrote:
> agk> Perhaps change the register/unregister interface to make it
> agk> symmetric: we always register and unregister when creating the
> agk> device, then set the integrity to the appropriate value - which
> agk> might include NULL - when the new table is put into place.
> 
> It seemed wasteful to register profiles since 99%+ of all storage
> devices out there that don't have a need for them.  That's why I
> deferred the allocation.  But I guess mere mortals compile without
> BLK_DEV_INTEGRITY anyway so it may not matter that much...
> 
> Jens, what do you think?

I agree, plus there are going to be lots of users running a
BLK_DEV_INTEGRITY enabled kernel but not having the hardware (distros).
So lazy alloc makes sense.

-- 
Jens Axboe