From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mga03.intel.com ([143.182.124.21]) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1T2MGe-0006pi-AP for linux-mtd@lists.infradead.org; Fri, 17 Aug 2012 13:07:12 +0000 Message-ID: <1345209115.27859.84.camel@sauron.fi.intel.com> Subject: Re: UBI fastmap updates From: Artem Bityutskiy To: Richard Weinberger Date: Fri, 17 Aug 2012 16:11:55 +0300 In-Reply-To: <1341836323-43916-1-git-send-email-richard@nod.at> References: <1341836323-43916-1-git-send-email-richard@nod.at> Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-+RQFhelgzX44+h1ZQMRM" Mime-Version: 1.0 Cc: nyoushchenko@mvista.com, linux-kernel@vger.kernel.org, adrian.hunter@intel.com, Heinz.Egger@linutronix.de, thomas.wucher@linutronix.de, linux-mtd@lists.infradead.org, shmulik.ladkani@gmail.com, tglx@linutronix.de, Marius.Mazarel@ugal.ro, tim.bird@am.sony.com Reply-To: artem.bityutskiy@linux.intel.com List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , --=-+RQFhelgzX44+h1ZQMRM Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Mon, 2012-07-09 at 14:18 +0200, Richard Weinberger wrote: > This is the next round of UBI fastmap updates. > It fixes all issues pointed out by Shmulik. :-) >=20 > If you want to test fastmap you can use my git repo: > git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubi2.git ubi2/v17 One thing which just came to my mind why looking at other MTD e-mails. I do not know if it is relevant for fastmap or not, just want you to check. In UBIFS we have we have the "fixup" feature which is used to work-around dumb flashers which are present in many factories: http://www.linux-mtd.infradead.org/faq/ubifs.html#L_free_space_fixup This is because the "correct" UBI flasher should be able to skip empty space when flashing, see here: http://www.linux-mtd.infradead.org/doc/ubi.html#L_flasher_algo So with this fixup flag UBIFS will basically read all its eraseblocks which have empty spece which it will use, and write them back. Just to make the empty space writable again. This is done only once on the very first boot. We do not do anything like this in UBI because UBI does not need this, it does not have any complex data structures on the media. With fastmap - I am unsure. I think it is not a problem, because probably you never append more data, you just re-write everything, right? --=20 Best Regards, Artem Bityutskiy --=-+RQFhelgzX44+h1ZQMRM Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAABAgAGBQJQLkMbAAoJECmIfjd9wqK0ZYgP/RzVGvW82uGMQb2BnfBEcsb9 uUBq3Ne14+I1ARZCHyiw7hOi0XTxNktOfu2jzKQlhRz4tbumAQY0Ex1ujXwO1lL9 9zEQN8EWNbyuzK64R+Uoy420Q9bgI22hS+zZ+rDkYqlw2OhR9AAaIqtSvxJPq+lT xhO6Fji5o6RIErXewBkBhNUd9CvOskDZ+njPxufvjbJiJzT8CTaCf/wcyq86D0Tc LiujdEQM+M+VHJ6NUDNuTkwgkTTxSSs0iEu6TXNSVAuA8yuJAukqwuyN6capdIpR r9d4otRtcQH/x4RVq6mUYkZOoanPHR4WA3G8vjhl8QfZR/o5bvL0LO0saXgXyBkY XIbzgaLjwzvl+WvGe/CRZmGsiA/dB0qL+tGKfEfYe2l2AOOXe1EVy1Cp/WyeajFF nSKFJB7zOLHwTlE0Yfs0nZ0xPV6DaaCR0gzwUKTtJJFSvzSHNN81qN4h00R1dxEA Io2mdmzk2tN+GM/b3rzW4991cMWoAvMRENIScO7AO3L9bcNE6e8e3lNClD/5LGi3 EPLZ5e6WyVyKsRvIIs/GZT/VM/Hxn3u0wSxdK+gqiX9aQbMggKDGmQKMXdSKGuwG TvFRie/3Y/0huIyHt+jPpaNjXkaEZt51VUYbix1a19JxQ33b4iPemWBKjkizdX30 WNFiD9JpAVuEZsMHB9gj =03PU -----END PGP SIGNATURE----- --=-+RQFhelgzX44+h1ZQMRM--