From patchwork Wed Nov 29 23:23:47 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luis Chamberlain X-Patchwork-Id: 10083855 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id D13F960234 for ; Wed, 29 Nov 2017 23:27:06 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C447C29D4B for ; Wed, 29 Nov 2017 23:27:06 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B8E4429D57; Wed, 29 Nov 2017 23:27:06 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 74FFF29D4B for ; Wed, 29 Nov 2017 23:27:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753060AbdK2XYG (ORCPT ); Wed, 29 Nov 2017 18:24:06 -0500 Received: from mail.kernel.org ([198.145.29.99]:53896 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752838AbdK2XYD (ORCPT ); Wed, 29 Nov 2017 18:24:03 -0500 Received: from garbanzo.do-not-panic.com (c-73-15-241-2.hsd1.ca.comcast.net [73.15.241.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id AE3DA21996; Wed, 29 Nov 2017 23:24:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AE3DA21996 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=mcgrof@kernel.org From: "Luis R. Rodriguez" To: viro@zeniv.linux.org.uk, bart.vanassche@wdc.com, ming.lei@redhat.com, tytso@mit.edu, darrick.wong@oracle.com, jikos@kernel.org, rjw@rjwysocki.net, pavel@ucw.cz, len.brown@intel.com, linux-fsdevel@vger.kernel.org Cc: boris.ostrovsky@oracle.com, jgross@suse.com, todd.e.brandt@linux.intel.com, nborisov@suse.com, jack@suse.cz, martin.petersen@oracle.com, ONeukum@suse.com, oleksandr@natalenko.name, oleg.b.antonyan@gmail.com, yu.chen.surf@gmail.com, dan.j.williams@intel.com, linux-pm@vger.kernel.org, linux-block@vger.kernel.org, linux-xfs@vger.kernel.org, linux-kernel@vger.kernel.org, "Luis R. Rodriguez" Subject: [PATCH 02/11] fs: provide unlocked helper thaw_super() Date: Wed, 29 Nov 2017 15:23:47 -0800 Message-Id: <20171129232356.28296-3-mcgrof@kernel.org> X-Mailer: git-send-email 2.13.2 In-Reply-To: <20171129232356.28296-1-mcgrof@kernel.org> References: <20171129232356.28296-1-mcgrof@kernel.org> Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP thaw_super() hold a write lock, however we wish to also enable callers which already hold the write lock. To do this provide a helper and make thaw_super() use it. This way, all that thaw_super() does now is lock handling and active count management. This change has no functional changes. Suggested-by: Dave Chinner Signed-off-by: Luis R. Rodriguez Reviewed-by: Jan Kara --- fs/super.c | 39 ++++++++++++++++++++++++++------------- 1 file changed, 26 insertions(+), 13 deletions(-) diff --git a/fs/super.c b/fs/super.c index a7650ff22f0e..cecc279beecd 100644 --- a/fs/super.c +++ b/fs/super.c @@ -1493,21 +1493,13 @@ int freeze_super(struct super_block *sb) } EXPORT_SYMBOL(freeze_super); -/** - * thaw_super -- unlock filesystem - * @sb: the super to thaw - * - * Unlocks the filesystem and marks it writeable again after freeze_super(). - */ -int thaw_super(struct super_block *sb) +/* Caller takes lock and handles active count */ +static int thaw_locked_super(struct super_block *sb) { int error; - down_write(&sb->s_umount); - if (sb->s_writers.frozen != SB_FREEZE_COMPLETE) { - up_write(&sb->s_umount); + if (sb->s_writers.frozen != SB_FREEZE_COMPLETE) return -EINVAL; - } if (sb_rdonly(sb)) { sb->s_writers.frozen = SB_UNFROZEN; @@ -1522,7 +1514,6 @@ int thaw_super(struct super_block *sb) printk(KERN_ERR "VFS:Filesystem thaw failed\n"); lockdep_sb_freeze_release(sb); - up_write(&sb->s_umount); return error; } } @@ -1531,7 +1522,29 @@ int thaw_super(struct super_block *sb) sb_freeze_unlock(sb); out: wake_up(&sb->s_writers.wait_unfrozen); - deactivate_locked_super(sb); return 0; } + +/** + * thaw_super -- unlock filesystem + * @sb: the super to thaw + * + * Unlocks the filesystem and marks it writeable again after freeze_super(). + */ +int thaw_super(struct super_block *sb) +{ + int error; + + down_write(&sb->s_umount); + error = thaw_locked_super(sb); + if (error) { + up_write(&sb->s_umount); + goto out; + } + + deactivate_locked_super(sb); + +out: + return error; +} EXPORT_SYMBOL(thaw_super);