From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: AHCI and add_disk_randomness() Date: Thu, 16 Nov 2006 13:40:29 +0100 Message-ID: <20061116124029.GA7164@kernel.dk> References: <1124564609.20061115220130@marki-online.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from brick.kernel.dk ([62.242.22.158]:36883 "EHLO kernel.dk") by vger.kernel.org with ESMTP id S1423869AbWKPMlB (ORCPT ); Thu, 16 Nov 2006 07:41:01 -0500 Content-Disposition: inline In-Reply-To: <1124564609.20061115220130@marki-online.net> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Marek Podmaka Cc: jgarzik@pobox.com, linux-ide@vger.kernel.org On Wed, Nov 15 2006, Marek Podmaka wrote: > Hello, > > I have server with Intel 5000V motherboard with integrated AHCI SATA > controller. It works well with kernel 2.6.18.2. But I have problem > with little entropy available and I'm not sure if one of the reasons > is that AHCI driver does not use add_disk_randomness() to contribute > to the kernel entropy pool. > > I'm not very skilled on kernel "hacking"... I tried finding where > this is called (it's defined in drivers/char/random.c and used for > example in Comapaq SmartArray driver in drivers/block/cciss.c). For > the SCSI part, I found it in scsi_lib.c, but I was not able to > determine if this is actually used by ahci/libata drivers. > > If not, would it be possible to implement it? I tried to figure out > where to call it by looking at cciss.c, but it seems that this is > totally different case, at least for me. I don't know where to add > it, because its parameter is struct gendisk *disk and didn't find it > used anywhere in ahci or libata. Since ahci attaches its devices through the scsi layer, add_disk_randomness() will get called from scsi_end_request() like for any other scsi controller. -- Jens Axboe