From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764852AbZE2U0j (ORCPT ); Fri, 29 May 2009 16:26:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932079AbZE2UU6 (ORCPT ); Fri, 29 May 2009 16:20:58 -0400 Received: from out02.mta.xmission.com ([166.70.13.232]:45229 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1763126AbZE2UT4 (ORCPT ); Fri, 29 May 2009 16:19:56 -0400 From: "Eric W. Biederman" To: Andrew Morton , Greg Kroah-Hartman Cc: , Tejun Heo , Cornelia Huck , , Kay Sievers , Greg KH , "Eric W. Biederman" , "Eric W. Biederman" Date: Fri, 29 May 2009 13:19:34 -0700 Message-Id: <1243628376-22905-24-git-send-email-ebiederm@xmission.com> X-Mailer: git-send-email 1.6.3.1.54.g99dd.dirty In-Reply-To: References: X-XM-SPF: eid=;;;mid=;;;hst=in01.mta.xmission.com;;;ip=76.21.114.89;;;frm=ebiederm@xmission.com;;;spf=neutral X-SA-Exim-Connect-IP: 76.21.114.89 X-SA-Exim-Rcpt-To: akpm@linux-foundation.org, gregkh@suse.de, linux-kernel@vger.kernel.org, tj@kernel.org, cornelia.huck@de.ibm.com, linux-fsdevel@vger.kernel.org, kay.sievers@vrfy.org, greg@kroah.com, ebiederm@xmission.com, ebiederm@aristanetworks.com X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-DCC: XMission; sa03 1397; Body=1 Fuz1=1 Fuz2=2 X-Spam-Combo: ;Andrew Morton , Greg Kroah-Hartman X-Spam-Relay-Country: X-Spam-Report: * -1.8 ALL_TRUSTED Passed through trusted hosts only via SMTP * 1.5 XMNoVowels Alpha-numberic number with no vowels * 0.0 T_TM2_M_HEADER_IN_MSG BODY: T_TM2_M_HEADER_IN_MSG * -2.6 BAYES_00 BODY: Bayesian spam probability is 0 to 1% * [score: 0.0000] * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa03 1397; Body=1 Fuz1=1 Fuz2=2] * 0.0 T_TooManySym_01 4+ unique symbols in subject * 0.0 XM_SPF_Neutral SPF-Neutral * 0.4 UNTRUSTED_Relay Comes from a non-trusted relay Subject: [PATCH 24/26] sysfs: Make sysfs_rename_link atomic X-SA-Exim-Version: 4.2.1 (built Thu, 25 Oct 2007 00:26:12 +0000) X-SA-Exim-Scanned: Yes (on in01.mta.xmission.com) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eric W. Biederman Use the existing sysfs_rename to make sysfs_rename_link an atomic operation that does less work. While I am at add additional sanity checking to ensure it is a symlink I am renaming. Acked-by: Kay Sievers Acked-by: Tejun Heo Signed-off-by: Eric W. Biederman --- fs/sysfs/symlink.c | 26 ++++++++++++++++++++++++-- 1 files changed, 24 insertions(+), 2 deletions(-) diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c index fc5fc86..39d050b 100644 --- a/fs/sysfs/symlink.c +++ b/fs/sysfs/symlink.c @@ -106,8 +106,30 @@ void sysfs_remove_link(struct kobject * kobj, const char * name) int sysfs_rename_link(struct kobject *kobj, struct kobject *targ, const char *old, const char *new) { - sysfs_remove_link(kobj, old); - return sysfs_create_link(kobj, targ, new); + struct sysfs_dirent *parent_sd, *sd = NULL; + int result; + + if (!kobj) + parent_sd = &sysfs_root; + else + parent_sd = kobj->sd; + + result = -ENOENT; + sd = sysfs_get_dirent(parent_sd, old); + if (!sd) + goto out; + + result = -EINVAL; + if (sysfs_type(sd) != SYSFS_KOBJ_LINK) + goto out; + if (sd->s_symlink.target_sd->s_dir.kobj != targ) + goto out; + + result = sysfs_rename(sd, parent_sd, new); + +out: + sysfs_put(sd); + return result; } static int sysfs_get_target_path(struct sysfs_dirent *parent_sd, -- 1.6.3.1.54.g99dd.dirty