Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932490AbVJaGeu (ORCPT ); Mon, 31 Oct 2005 01:34:50 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932491AbVJaGeu (ORCPT ); Mon, 31 Oct 2005 01:34:50 -0500 Received: from ns1.suse.de ([195.135.220.2]:13487 "EHLO mx1.suse.de") by vger.kernel.org with ESMTP id S932490AbVJaGeu (ORCPT ); Mon, 31 Oct 2005 01:34:50 -0500 From: NeilBrown To: Andrew Morton Date: Mon, 31 Oct 2005 17:34:44 +1100 Message-Id: <1051031063444.9586@suse.de> X-face: [Gw_3E*Gng}4rRrKRYotwlE?.2|**#s9D Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1491 Lines: 48 According to Posix and SUS, truncate(2) and ftruncate(2) only update ctime and mtime if the size actually changes. Linux doesn't currently obey this. There is no need to test the size under i_sem, as loosing any race will not make a noticable different the mtime or ctime. (According to SUS, truncate and ftruncate 'may' clear setuid/setgid as well, currently we don't. Should we? ) Signed-off-by: Neil Brown ### Diffstat output ./fs/open.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff ./fs/open.c~current~ ./fs/open.c --- ./fs/open.c~current~ 2005-10-31 16:22:44.000000000 +1100 +++ ./fs/open.c 2005-10-31 16:22:44.000000000 +1100 @@ -260,7 +260,8 @@ static inline long do_sys_truncate(const goto dput_and_out; error = locks_verify_truncate(inode, NULL, length); - if (!error) { + if (!error && + length != i_size_read(dentry->d_inode)) { DQUOT_INIT(inode); error = do_truncate(nd.dentry, length); } @@ -313,7 +314,8 @@ static inline long do_sys_ftruncate(unsi goto out_putf; error = locks_verify_truncate(inode, file, length); - if (!error) + if (!error && + length != i_size_read(dentry->d_inode)) error = do_truncate(dentry, length); out_putf: fput(file); - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/