Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752651Ab2HZGrm (ORCPT ); Sun, 26 Aug 2012 02:47:42 -0400 Received: from mail-vb0-f46.google.com ([209.85.212.46]:57127 "EHLO mail-vb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751514Ab2HZGrk (ORCPT ); Sun, 26 Aug 2012 02:47:40 -0400 MIME-Version: 1.0 In-Reply-To: <20120826090603.6b833e54@pixies.home.jungo.com> References: <1345904767-23011-1-git-send-email-shijie8@gmail.com> <20120825120231.73577d6a@halley> <20120826090603.6b833e54@pixies.home.jungo.com> Date: Sun, 26 Aug 2012 02:47:39 -0400 Message-ID: Subject: Re: [PATCH v2] mtd: cmdlinepart: fix the wrong partitions number when truncating occurs From: Huang Shijie To: Shmulik Ladkani Cc: dwmw2@infradead.org, linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org, dedekind1@gmail.com Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2529 Lines: 72 On Sun, Aug 26, 2012 at 2:06 AM, Shmulik Ladkani wrote: > Hi, > > On Sat, 25 Aug 2012 05:26:51 -0400 Huang Shijie wrote: >> On Sat, Aug 25, 2012 at 5:02 AM, Shmulik Ladkani >> wrote: >> > Your analysis seems right, but let me offer an alternative approach. >> > >> > I would simply: >> > >> > - part->num_parts = i; >> your code does not wors in such kernel command line(also with the 1GB >> nand chip): >> #gpmi-nand:100m(root),100m(kernel),1g(rootfs),1g(user),-(rest) >> > > Can you please detail what do you mean by "not work"? sorry. :) My meaning was the result is unreadable. It looks too strange. That's why i use the 'break' to shortcut the loop. > > To my understanding, in this example, according to my suggestion, the > resulting partitions would be: > > root 100m@0 > kernel 100m@100m > rootfs 800m@200m (truncated) > user 0@1g (truncated) > rest 0@1g > yes, the result is like this. > Reasonable IMO, given the fact that the mtd device size is smaller than > the specified parts. > > I saw you submitted a patch which sorts the cmdline parts; I don't > understand why this is necessary. > Also, sorting might not be desirable, as the user specified the unsorted > partitions might have _wanted_ them to appear in that order. > > Now lets focus on your original suggestion and its consequences: > > - Orignal code STOPPED parsing at the 1st truncated partition, > this partition WAS NOT returned to the caller > - Your patch STOPS AFTER parsing the 1st truncated partition, > this partiton IS returned to the caller (but partitions specified > later are no longer parsed) > - My suggestion CONTINUES parsing all partitions. > So later partitions (specified with the 'size' but *without* 'offset') > will be truncated AND presented to the caller. > AND, if later partitions are specified using the 'size@offset' > explicit format, they are parsed normally. > Could Artem or David point us a direction about this? [1] Should the unsorted partitions be supported? [2] And what should we do when we meet a 1GB nand, and the cmdline is gpmi-nand:100m(root),100m(kernel),1g(rootfs),1g(user),-(rest) thanks a lot Huang Shijie -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/