From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D2317C6FA99 for ; Fri, 10 Mar 2023 14:40:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232732AbjCJOks (ORCPT ); Fri, 10 Mar 2023 09:40:48 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56936 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232691AbjCJOks (ORCPT ); Fri, 10 Mar 2023 09:40:48 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 029B41219F0 for ; Fri, 10 Mar 2023 06:40:47 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id A967AB822DE for ; Fri, 10 Mar 2023 14:40:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1CF3DC433D2; Fri, 10 Mar 2023 14:40:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678459244; bh=jUIvIeo1ycQNA9TrL8sm8mSPuhbigmEZbFbErarSjCE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=q2ygSQlHihTFTg5X9HpuOEQMthjJu8gsw/yZqcBHmANG8y2jSe/WlO2rkRsIk1mnu oyedbV5h/q31F8C8Es6HKImlNPlpfU+rThF34UENoAzPlpGcqW46SnIAEMZlOpv+co f7Zo8iDgTyYpihZdRFAaIJqrHmK+OSnsgyRRyrs0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Zhihao Cheng , Richard Weinberger , Sasha Levin Subject: [PATCH 5.4 297/357] ubifs: Reserve one leb for each journal head while doing budget Date: Fri, 10 Mar 2023 14:39:46 +0100 Message-Id: <20230310133747.861086956@linuxfoundation.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230310133733.973883071@linuxfoundation.org> References: <20230310133733.973883071@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Zhihao Cheng [ Upstream commit e874dcde1cbf82c786c0e7f2899811c02630cc52 ] UBIFS calculates available space by c->main_bytes - c->lst.total_used (which means non-index lebs' free and dirty space is accounted into total available), then index lebs and four lebs (one for gc_lnum, one for deletions, two for journal heads) are deducted. In following situation, ubifs may get -ENOSPC from make_reservation(): LEB 84: DATAHD free 122880 used 1920 dirty 2176 dark 6144 LEB 110:DELETION free 126976 used 0 dirty 0 dark 6144 (empty) LEB 201:gc_lnum free 126976 used 0 dirty 0 dark 6144 LEB 272:GCHD free 77824 used 47672 dirty 1480 dark 6144 LEB 356:BASEHD free 0 used 39776 dirty 87200 dark 6144 OTHERS: index lebs, zero-available non-index lebs UBIFS calculates the available bytes is 6888 (How to calculate it: 126976 * 5[remain main bytes] - 1920[used] - 47672[used] - 39776[used] - 126976 * 1[deletions] - 126976 * 1[gc_lnum] - 126976 * 2[journal heads] - 6144 * 5[dark] = 6888) after doing budget, however UBIFS cannot use BASEHD's dirty space(87200), because UBIFS cannot find next BASEHD to reclaim current BASEHD. (c->bi.min_idx_lebs equals to c->lst.idx_lebs, the empty leb won't be found by ubifs_find_free_space(), and dirty index lebs won't be picked as gced lebs. All non-index lebs has dirty space less then c->dead_wm, non-index lebs won't be picked as gced lebs either. So new free lebs won't be produced.). See more details in Link. To fix it, reserve one leb for each journal head while doing budget. Link: https://bugzilla.kernel.org/show_bug.cgi?id=216562 Fixes: 1e51764a3c2ac0 ("UBIFS: add new flash file system") Signed-off-by: Zhihao Cheng Signed-off-by: Richard Weinberger Signed-off-by: Sasha Levin --- fs/ubifs/budget.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/fs/ubifs/budget.c b/fs/ubifs/budget.c index bdb79be6dc0e2..9cb05ef9b9dd9 100644 --- a/fs/ubifs/budget.c +++ b/fs/ubifs/budget.c @@ -212,11 +212,10 @@ long long ubifs_calc_available(const struct ubifs_info *c, int min_idx_lebs) subtract_lebs += 1; /* - * The GC journal head LEB is not really accessible. And since - * different write types go to different heads, we may count only on - * one head's space. + * Since different write types go to different heads, we should + * reserve one leb for each head. */ - subtract_lebs += c->jhead_cnt - 1; + subtract_lebs += c->jhead_cnt; /* We also reserve one LEB for deletions, which bypass budgeting */ subtract_lebs += 1; -- 2.39.2