From patchwork Thu Apr 9 21:34:53 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Omar Sandoval X-Patchwork-Id: 6190981 Return-Path: X-Original-To: patchwork-linux-btrfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 9C30ABF4A6 for ; Thu, 9 Apr 2015 21:36:42 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id A8BCC2037A for ; Thu, 9 Apr 2015 21:36:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 957F22037E for ; Thu, 9 Apr 2015 21:36:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752890AbbDIVgh (ORCPT ); Thu, 9 Apr 2015 17:36:37 -0400 Received: from mail-pa0-f52.google.com ([209.85.220.52]:36392 "EHLO mail-pa0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753644AbbDIVf0 (ORCPT ); Thu, 9 Apr 2015 17:35:26 -0400 Received: by pabsx10 with SMTP id sx10so270114pab.3 for ; Thu, 09 Apr 2015 14:35:25 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:in-reply-to:references; bh=9kZA8rXTiUsqc9GikgN1Hux9sGd0AhBK8YjDBSl0DTc=; b=dZTMzDAJjQc4ki/9csMkAzW/8wFqOosc2CkQib4W9AAnVuzswT/zUa8tnsAdm72Okk OVPlivUL2PgpqFinZljx60vAixnYz8bBTe/KE7Be7THHVOu69jHlPLlrz+dJrf0D7Ijv hNIGNVUtRWtsV20u+fWeNYUZCcmXXMdDT2aXKbA6hgNYmjhYXH8N5GAIn7x/89/y7Rmr /s7UTz+ru28XLxi/UkrUB7WUSviPQxhqh3s+dWDmLk196Z3M+GUupUJfoG8OCVwmDXHG FH92GMupQq0dREl/y0iDwJBqMeIInjngqUeafMpWdmoj+WBGQVykbwuq3usCSHsPwlx0 bvYw== X-Gm-Message-State: ALoCoQnpXLEopTkP6Pl4714PY/W/pIe6+n8KoVM9vaHxLFiziq5fEt2HnP+AuhF596jdqYJlEex8 X-Received: by 10.66.253.225 with SMTP id ad1mr59405622pad.65.1428615325880; Thu, 09 Apr 2015 14:35:25 -0700 (PDT) Received: from mew.localdomain (c-76-104-211-44.hsd1.wa.comcast.net. [76.104.211.44]) by mx.google.com with ESMTPSA id ot6sm15540730pdb.28.2015.04.09.14.35.24 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Thu, 09 Apr 2015 14:35:25 -0700 (PDT) From: Omar Sandoval To: Chris Mason , Josef Bacik , David Sterba , linux-btrfs@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Qu Wenruo , Omar Sandoval Subject: [PATCH v2 3/6] Btrfs: clean up error handling in mount_subvol() Date: Thu, 9 Apr 2015 14:34:53 -0700 Message-Id: <607a31672e1eb72dafbca88c816187dd3b0846a6.1428614837.git.osandov@osandov.com> X-Mailer: git-send-email 2.3.5 In-Reply-To: References: In-Reply-To: References: Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP In preparation for new functionality in mount_subvol(), give it ownership of subvol_name and tidy up the error paths. Signed-off-by: Omar Sandoval Reviewed-by: David Sterba --- fs/btrfs/super.c | 61 ++++++++++++++++++++++++++++++-------------------------- 1 file changed, 33 insertions(+), 28 deletions(-) diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index bac3c9a..ab100e5 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1167,55 +1167,61 @@ static struct dentry *mount_subvol(const char *subvol_name, int flags, const char *device_name, char *data) { struct dentry *root; - struct vfsmount *mnt; + struct vfsmount *mnt = NULL; char *newargs; + int ret; newargs = setup_root_args(data); - if (!newargs) - return ERR_PTR(-ENOMEM); - mnt = vfs_kern_mount(&btrfs_fs_type, flags, device_name, - newargs); + if (!newargs) { + root = ERR_PTR(-ENOMEM); + goto out; + } - if (PTR_RET(mnt) == -EBUSY) { + mnt = vfs_kern_mount(&btrfs_fs_type, flags, device_name, newargs); + if (PTR_ERR_OR_ZERO(mnt) == -EBUSY) { if (flags & MS_RDONLY) { - mnt = vfs_kern_mount(&btrfs_fs_type, flags & ~MS_RDONLY, device_name, - newargs); + mnt = vfs_kern_mount(&btrfs_fs_type, flags & ~MS_RDONLY, + device_name, newargs); } else { - int r; - mnt = vfs_kern_mount(&btrfs_fs_type, flags | MS_RDONLY, device_name, - newargs); + mnt = vfs_kern_mount(&btrfs_fs_type, flags | MS_RDONLY, + device_name, newargs); if (IS_ERR(mnt)) { - kfree(newargs); - return ERR_CAST(mnt); + root = ERR_CAST(mnt); + mnt = NULL; + goto out; } down_write(&mnt->mnt_sb->s_umount); - r = btrfs_remount(mnt->mnt_sb, &flags, NULL); + ret = btrfs_remount(mnt->mnt_sb, &flags, NULL); up_write(&mnt->mnt_sb->s_umount); - if (r < 0) { - /* FIXME: release vfsmount mnt ??*/ - kfree(newargs); - return ERR_PTR(r); + if (ret < 0) { + root = ERR_PTR(ret); + goto out; } } } - - kfree(newargs); - - if (IS_ERR(mnt)) - return ERR_CAST(mnt); + if (IS_ERR(mnt)) { + root = ERR_CAST(mnt); + mnt = NULL; + goto out; + } root = mount_subtree(mnt, subvol_name); + /* mount_subtree() drops our reference on the vfsmount. */ + mnt = NULL; if (!IS_ERR(root) && !is_subvolume_inode(root->d_inode)) { struct super_block *s = root->d_sb; dput(root); root = ERR_PTR(-EINVAL); deactivate_locked_super(s); - printk(KERN_ERR "BTRFS: '%s' is not a valid subvolume\n", - subvol_name); + pr_err("BTRFS: '%s' is not a valid subvolume\n", subvol_name); } +out: + mntput(mnt); + kfree(newargs); + kfree(subvol_name); return root; } @@ -1301,9 +1307,8 @@ static struct dentry *btrfs_mount(struct file_system_type *fs_type, int flags, } if (subvol_name) { - root = mount_subvol(subvol_name, flags, device_name, data); - kfree(subvol_name); - return root; + /* mount_subvol() will free subvol_name. */ + return mount_subvol(subvol_name, flags, device_name, data); } security_init_mnt_opts(&new_sec_opts);