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 8CF23C433EF for ; Mon, 27 Jun 2022 11:47:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237886AbiF0LrU (ORCPT ); Mon, 27 Jun 2022 07:47:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42042 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237497AbiF0Lm7 (ORCPT ); Mon, 27 Jun 2022 07:42:59 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ECAAE10CD; Mon, 27 Jun 2022 04:38:26 -0700 (PDT) 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 B13D1B8111B; Mon, 27 Jun 2022 11:38:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2F066C3411D; Mon, 27 Jun 2022 11:38:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1656329904; bh=o/oKP+PClE6ic2Rr0Q5Dzsw99u0cmJEBX6BfIJmBu2g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oWGWATtzQnpacVmBOS1EKg3Hma/v0qdnSvJXN3NDSjM73bUdNHC0YsVHgsE71VguD FCUTnbX/AJuoneyyL7sq8cy7nr1KyifXkc3fJsEPdkLxD6xqBOX7KzfGKOGuONGWQI ImRBOu5gojHGBfKNyde8gqddu9tBJK6bGx9e0mxg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Qu Wenruo , David Sterba Subject: [PATCH 5.18 019/181] btrfs: prevent remounting to v1 space cache for subpage mount Date: Mon, 27 Jun 2022 13:19:52 +0200 Message-Id: <20220627111945.120948579@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220627111944.553492442@linuxfoundation.org> References: <20220627111944.553492442@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Qu Wenruo commit 0591f04036218d572d54349ea8c7914ad9c82b2b upstream. Upstream commit 9f73f1aef98b ("btrfs: force v2 space cache usage for subpage mount") forces subpage mount to use v2 cache, to avoid deprecated v1 cache which doesn't support subpage properly. But there is a loophole that user can still remount to v1 cache. The existing check will only give users a warning, but does not really prevent to do the remount. Although remounting to v1 will not cause any problems since the v1 cache will always be marked invalid when mounted with a different page size, it's still better to prevent v1 cache at all for subpage mounts. Fixes: 9f73f1aef98b ("btrfs: force v2 space cache usage for subpage mount") CC: stable@vger.kernel.org # 5.15+ Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/super.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1986,6 +1986,14 @@ static int btrfs_remount(struct super_bl if (ret) goto restore; + /* V1 cache is not supported for subpage mount. */ + if (fs_info->sectorsize < PAGE_SIZE && btrfs_test_opt(fs_info, SPACE_CACHE)) { + btrfs_warn(fs_info, + "v1 space cache is not supported for page size %lu with sectorsize %u", + PAGE_SIZE, fs_info->sectorsize); + ret = -EINVAL; + goto restore; + } btrfs_remount_begin(fs_info, old_opts, *flags); btrfs_resize_thread_pool(fs_info, fs_info->thread_pool_size, old_thread_pool_size);