From patchwork Fri Dec 23 08:14:52 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yongqiang Yang X-Patchwork-Id: 132997 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id AE0DBB7001 for ; Fri, 23 Dec 2011 22:53:01 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756647Ab1LWLxA (ORCPT ); Fri, 23 Dec 2011 06:53:00 -0500 Received: from mail-gx0-f174.google.com ([209.85.161.174]:61358 "EHLO mail-gx0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751473Ab1LWLxA (ORCPT ); Fri, 23 Dec 2011 06:53:00 -0500 Received: by ggdk6 with SMTP id k6so6769627ggd.19 for ; Fri, 23 Dec 2011 03:52:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; bh=/Kjna2eCV0FSNKDbcm30RUkvkW71G8joXKmVlDG4Y+U=; b=lajxKl/Ybzm94uMxRXBoM5pNls2Es0w5df+98D+FhYFiftjyHiDRaezn+52AQcu+R1 8D3lTu/QgGiug4R0hrHvSw9ctsWPMemdyEKR/yCHzDtB7M/TaL+qASoJY7IYEOL9phKS ijcqvy9e4A0p1Hz2R7j2iS6NVOOTNqk7HLQZM= Received: by 10.50.189.194 with SMTP id gk2mr13292598igc.0.1324641179440; Fri, 23 Dec 2011 03:52:59 -0800 (PST) Received: from localhost.localdomain ([159.226.43.42]) by mx.google.com with ESMTPS id i2sm9968543igq.6.2011.12.23.03.52.57 (version=TLSv1/SSLv3 cipher=OTHER); Fri, 23 Dec 2011 03:52:58 -0800 (PST) From: Yongqiang Yang To: linux-ext4@vger.kernel.org Cc: tytso@mit.edu, Yongqiang Yang Subject: [PATCH v5 02/15] ext4: add a function which adds a new desc to a fs Date: Fri, 23 Dec 2011 16:14:52 +0800 Message-Id: <1324628105-32559-3-git-send-email-xiaoqiangnk@gmail.com> X-Mailer: git-send-email 1.7.5.1 In-Reply-To: <1324628105-32559-1-git-send-email-xiaoqiangnk@gmail.com> References: <1324628105-32559-1-git-send-email-xiaoqiangnk@gmail.com> Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org From: Yongqiang Yang This patch adds a function named ext4_add_new_desc() which adds a new desc to a fs and whose code is copied from ext4_group_add(). The function will be used by new resize implementation. Signed-off-by: Yongqiang Yang Signed-off-by: "Theodore Ts'o" --- fs/ext4/resize.c | 42 ++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 42 insertions(+), 0 deletions(-) diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index ac5565c..9a5486e 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -735,6 +735,48 @@ exit_err: } } +/* + * ext4_add_new_desc() adds group descriptor of group @group + * + * @handle: journal handle + * @sb; super block + * @group: the group no. of the first group desc to be added + * @resize_inode: the resize inode + */ +static int ext4_add_new_desc(handle_t *handle, struct super_block *sb, + ext4_group_t group, struct inode *resize_inode) +{ + struct ext4_sb_info *sbi = EXT4_SB(sb); + struct ext4_super_block *es = sbi->s_es; + struct buffer_head *gdb_bh; + int gdb_off, gdb_num, err = 0; + int reserved_gdb = ext4_bg_has_super(sb, group) ? + le16_to_cpu(es->s_reserved_gdt_blocks) : 0; + + gdb_off = group % EXT4_DESC_PER_BLOCK(sb); + gdb_num = group / EXT4_DESC_PER_BLOCK(sb); + + /* + * We will only either add reserved group blocks to a backup group + * or remove reserved blocks for the first group in a new group block. + * Doing both would be mean more complex code, and sane people don't + * use non-sparse filesystems anymore. This is already checked above. + */ + if (gdb_off) { + gdb_bh = sbi->s_group_desc[gdb_num]; + err = ext4_journal_get_write_access(handle, gdb_bh); + if (err) + goto out; + + if (reserved_gdb && ext4_bg_num_gdb(sb, group)) + err = reserve_backup_gdb(handle, resize_inode, group); + } else + err = add_new_gdb(handle, resize_inode, group); + +out: + return err; +} + /* Add group descriptor data to an existing or new group descriptor block. * Ensure we handle all possible error conditions _before_ we start modifying * the filesystem, because we cannot abort the transaction and not have it