From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757514AbYGDBXf (ORCPT ); Thu, 3 Jul 2008 21:23:35 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756682AbYGDBWD (ORCPT ); Thu, 3 Jul 2008 21:22:03 -0400 Received: from out01.mta.xmission.com ([166.70.13.231]:57985 "EHLO out01.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755369AbYGDBVx (ORCPT ); Thu, 3 Jul 2008 21:21:53 -0400 From: ebiederm@xmission.com (Eric W. Biederman) To: Greg Kroah-Hartman , Andrew Morton Cc: Tejun Heo , Daniel Lezcano , linux-kernel@vger.kernel.org, Al Viro , Linux Containers , Benjamin Thery , References: <20080618170729.808539948@theryb.frec.bull.fr> <486AF4FA.8020805@gmail.com> <486B060C.7030607@gmail.com> <486C4515.1070007@gmail.com> <486CB051.5000507@fr.ibm.com> <486CF71F.5090405@gmail.com> Date: Thu, 03 Jul 2008 18:17:30 -0700 In-Reply-To: (Eric W. Biederman's message of "Thu, 03 Jul 2008 18:16:08 -0700") Message-ID: User-Agent: Gnus/5.110006 (No Gnus v0.6) Emacs/21.4 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-SA-Exim-Connect-IP: 24.130.11.59 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-DCC: XMission; sa02 1397; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ;Greg Kroah-Hartman , Andrew Morton X-Spam-Relay-Country: X-Spam-Report: * -1.8 ALL_TRUSTED Passed through trusted hosts only via SMTP * -2.6 BAYES_00 BODY: Bayesian spam probability is 0 to 1% * [score: 0.0001] * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa02 1397; Body=1 Fuz1=1 Fuz2=1] * 0.0 XM_SPF_Neutral SPF-Neutral Subject: [PATCH 10/15] sysfs: Merge sysfs_rename_dir and sysfs_move_dir X-SA-Exim-Version: 4.2 (built Thu, 03 Mar 2005 10:44:12 +0100) X-SA-Exim-Scanned: Yes (on mgr1.xmission.com) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org These two functions do 90% of the same work and it doesn't significantly obfuscate the function to allow both the parent dir and the name to change at the same time. So merge them together to simplify maintenance, and increase testing. Signed-off-by: Eric W. Biederman --- fs/sysfs/dir.c | 121 +++++++++++++++++-------------------------------------- 1 files changed, 38 insertions(+), 83 deletions(-) diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 6dc3376..fe2bb1c 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -924,44 +924,57 @@ err_out: return error; } -int sysfs_rename_dir(struct kobject * kobj, const char *new_name) +static int sysfs_mv_dir(struct sysfs_dirent *sd, + struct sysfs_dirent *new_parent_sd, const char *new_name) { - struct sysfs_dirent *sd = kobj->sd; struct list_head todo; struct sysfs_rename_struct *srs; - struct inode *parent_inode = NULL; + struct inode *old_parent_inode = NULL, *new_parent_inode = NULL; const char *dup_name = NULL; const void *old_tag, *tag; int error; INIT_LIST_HEAD(&todo); + BUG_ON(!sd->s_parent); mutex_lock(&sysfs_rename_mutex); + if (!new_parent_sd) + new_parent_sd = &sysfs_root; + old_tag = sd->s_tag; tag = sysfs_creation_tag(sd->s_parent, sd); error = 0; - if ((old_tag == tag) && (strcmp(sd->s_name, new_name) == 0)) - goto out; /* nothing to rename */ + if ((sd->s_parent == new_parent_sd) && (old_tag == tag) && + (strcmp(sd->s_name, new_name) == 0)) + goto out; /* nothing to do */ sysfs_grab_supers(); if (old_tag == tag) { - error = prep_rename(&todo, sd, sd->s_parent, new_name); + error = prep_rename(&todo, sd, new_parent_sd, new_name); if (error) goto out_release; } error = -ENOMEM; mutex_lock(&sysfs_mutex); - parent_inode = sysfs_get_inode(sd->s_parent); + old_parent_inode = sysfs_get_inode(sd->s_parent); + new_parent_inode = sysfs_get_inode(new_parent_sd); mutex_unlock(&sysfs_mutex); - if (!parent_inode) + if (!old_parent_inode || !new_parent_inode) goto out_release; - mutex_lock(&parent_inode->i_mutex); +again: + mutex_lock(&old_parent_inode->i_mutex); + if (old_parent_inode != new_parent_inode) { + if (!mutex_trylock(&new_parent_inode->i_mutex)) { + mutex_unlock(&old_parent_inode->i_mutex); + goto again; + } + } mutex_lock(&sysfs_mutex); error = -EEXIST; - if (sysfs_find_dirent(sd->s_parent, tag, new_name)) + if (sysfs_find_dirent(new_parent_sd, tag, new_name)) goto out_unlock; /* rename sysfs_dirent */ @@ -974,7 +987,7 @@ int sysfs_rename_dir(struct kobject * kobj, const char *new_name) sd->s_name = new_name; sd->s_tag = tag; - /* rename */ + /* rename dcache entries */ list_for_each_entry(srs, &todo, list) { d_add(srs->new_dentry, NULL); d_move(srs->old_dentry, srs->new_dentry); @@ -994,77 +1007,6 @@ int sysfs_rename_dir(struct kobject * kobj, const char *new_name) } } - error = 0; -out_unlock: - mutex_unlock(&sysfs_mutex); - mutex_unlock(&parent_inode->i_mutex); - kfree(dup_name); -out_release: - iput(parent_inode); - post_rename(&todo); - sysfs_release_supers(); -out: - mutex_unlock(&sysfs_rename_mutex); - return error; -} - -int sysfs_move_dir(struct kobject *kobj, struct kobject *new_parent_kobj) -{ - struct sysfs_dirent *sd = kobj->sd; - struct sysfs_dirent *new_parent_sd; - struct list_head todo; - struct sysfs_rename_struct *srs; - struct inode *old_parent_inode = NULL, *new_parent_inode = NULL; - int error; - const void *tag; - - INIT_LIST_HEAD(&todo); - mutex_lock(&sysfs_rename_mutex); - BUG_ON(!sd->s_parent); - new_parent_sd = new_parent_kobj->sd ? new_parent_kobj->sd : &sysfs_root; - tag = sd->s_tag; - - error = 0; - if (sd->s_parent == new_parent_sd) - goto out; /* nothing to move */ - - sysfs_grab_supers(); - error = prep_rename(&todo, sd, new_parent_sd, sd->s_name); - if (error) - goto out_release; - - error = -ENOMEM; - mutex_lock(&sysfs_mutex); - old_parent_inode = sysfs_get_inode(sd->s_parent); - mutex_unlock(&sysfs_mutex); - if (!old_parent_inode) - goto out_release; - - error = -ENOMEM; - mutex_lock(&sysfs_mutex); - new_parent_inode = sysfs_get_inode(new_parent_sd); - mutex_unlock(&sysfs_mutex); - if (!new_parent_inode) - goto out_release; - -again: - mutex_lock(&old_parent_inode->i_mutex); - if (!mutex_trylock(&new_parent_inode->i_mutex)) { - mutex_unlock(&old_parent_inode->i_mutex); - goto again; - } - mutex_lock(&sysfs_mutex); - - error = -EEXIST; - if (sysfs_find_dirent(new_parent_sd, tag, sd->s_name)) - goto out_unlock; - - error = 0; - list_for_each_entry(srs, &todo, list) { - d_add(srs->new_dentry, NULL); - d_move(srs->old_dentry, srs->new_dentry); - } - /* Remove from old parent's list and insert into new parent's list. */ sysfs_unlink_sibling(sd); sysfs_get(new_parent_sd); @@ -1072,10 +1014,13 @@ again: sd->s_parent = new_parent_sd; sysfs_link_sibling(sd); + error = 0; out_unlock: mutex_unlock(&sysfs_mutex); - mutex_unlock(&new_parent_inode->i_mutex); + if (new_parent_inode != old_parent_inode) + mutex_unlock(&new_parent_inode->i_mutex); mutex_unlock(&old_parent_inode->i_mutex); + kfree(dup_name); out_release: iput(new_parent_inode); @@ -1087,6 +1032,16 @@ out: return error; } +int sysfs_rename_dir(struct kobject * kobj, const char *new_name) +{ + return sysfs_mv_dir(kobj->sd, kobj->sd->s_parent, new_name); +} + +int sysfs_move_dir(struct kobject *kobj, struct kobject *new_parent_kobj) +{ + return sysfs_mv_dir(kobj->sd, new_parent_kobj->sd, kobj->sd->s_name); +} + /* Relationship between s_mode and the DT_xxx types */ static inline unsigned char dt_type(struct sysfs_dirent *sd) { -- 1.5.3.rc6.17.g1911