From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1422654AbWF0WQG (ORCPT ); Tue, 27 Jun 2006 18:16:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1422653AbWF0WPh (ORCPT ); Tue, 27 Jun 2006 18:15:37 -0400 Received: from e36.co.us.ibm.com ([32.97.110.154]:11483 "EHLO e36.co.us.ibm.com") by vger.kernel.org with ESMTP id S1030460AbWF0WO4 (ORCPT ); Tue, 27 Jun 2006 18:14:56 -0400 Subject: [PATCH 13/20] elevate writer count for do_sys_truncate() To: akpm@osdl.org Cc: linux-kernel@vger.kernel.org, herbert@13thfloor.at, viro@ftp.linux.org.uk, serue@us.ibm.com, Dave Hansen From: Dave Hansen Date: Tue, 27 Jun 2006 15:14:51 -0700 References: <20060627221436.77CCB048@localhost.localdomain> In-Reply-To: <20060627221436.77CCB048@localhost.localdomain> Message-Id: <20060627221451.F53855F4@localhost.localdomain> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Signed-off-by: Dave Hansen --- lxc-dave/fs/open.c | 16 +++++++++++----- 1 files changed, 11 insertions(+), 5 deletions(-) diff -puN fs/open.c~C-elevate-writers-opens-part2-do_sys_truncate fs/open.c --- lxc/fs/open.c~C-elevate-writers-opens-part2-do_sys_truncate 2006-06-27 10:40:32.000000000 -0700 +++ lxc-dave/fs/open.c 2006-06-27 10:40:32.000000000 -0700 @@ -244,28 +244,32 @@ static long do_sys_truncate(const char _ if (!S_ISREG(inode->i_mode)) goto dput_and_out; - error = vfs_permission(&nd, MAY_WRITE); + error = mnt_want_write(nd.mnt); if (error) goto dput_and_out; + error = vfs_permission(&nd, MAY_WRITE); + if (error) + goto mnt_drop_write_and_out; + error = -EROFS; if (IS_RDONLY(inode)) - goto dput_and_out; + goto mnt_drop_write_and_out; error = -EPERM; if (IS_IMMUTABLE(inode) || IS_APPEND(inode)) - goto dput_and_out; + goto mnt_drop_write_and_out; /* * Make sure that there are no leases. */ error = break_lease(inode, FMODE_WRITE); if (error) - goto dput_and_out; + goto mnt_drop_write_and_out; error = get_write_access(inode); if (error) - goto dput_and_out; + goto mnt_drop_write_and_out; error = locks_verify_truncate(inode, NULL, length); if (!error) { @@ -274,6 +278,8 @@ static long do_sys_truncate(const char _ } put_write_access(inode); +mnt_drop_write_and_out: + mnt_drop_write(nd.mnt); dput_and_out: path_release(&nd); out: _