From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from a.ns.miles-group.at ([95.130.255.143] helo=radon.swed.at) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1YYGv7-0007BT-QO for linux-mtd@lists.infradead.org; Wed, 18 Mar 2015 16:34:15 +0000 Message-ID: <5509A8EA.10201@nod.at> Date: Wed, 18 Mar 2015 17:33:46 +0100 From: Richard Weinberger MIME-Version: 1.0 To: Tanya Brokhman , ricard.wanderlof@axis.com Subject: Re: [PATCH 2/2] ubi-utils: ubinize: Add fastmap suport to image creation References: <1426668763-6463-1-git-send-email-tlinder@codeaurora.org> <550951C9.2040509@nod.at> <550956D7.9030309@codeaurora.org> <55095E45.8030401@nod.at> <55096BA6.1030708@codeaurora.org> <55096D6D.5000707@nod.at> <5509725F.6050606@codeaurora.org> In-Reply-To: <5509725F.6050606@codeaurora.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: linux-mtd@lists.infradead.org, Artem Bityutskiy List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Am 18.03.2015 um 13:41 schrieb Tanya Brokhman: > (thinking out-loud, trying not to reveal our flasher details) > UBI aware flasher has to: > 1. scan partition and collect ec values > 2. for each PEB of the image: update the ec_header, erase PEB and flash the image > 3. for remaining empty PEBs erase and write ec_heaser > > For generating FM in flasher we need to update #2 and while flashing the image construct the FM data in memory. (what PEB, for what volume etc). this is O(1) > > When we have the layout in memory we need to construct the actual FM data => go over all lists => O(number of dev PEBs) => probably can be neglected as well. > > Ok, I take it back: run time wont be effected. What will be effected is memory consumption. Yeah, but a smart flasher would of course not keep the whole image in memory. > If I remember correctly, when we discussed this whole idea a while back you mentioned that a lot of users use their own proprietary flasher. So from your experience: you think > users will prefer to have a libfastmap and not ubinize enhancement? > Maybe implementing libfastmap to be added to any flasher isn't such a bad idea. Then the whole "ubi awareness" can be implemented there. > I wasn't aware of the fact that ubinize is skipped. Is this common? I've seen that more than once. Customers tend to use their own non-trivial tools. ;) If we implement libfastmap ubinize could also use it (plus a big fat warning that you'll need a fastmap aware flasher). Thanks, //richard