From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756308AbXD1Nng (ORCPT ); Sat, 28 Apr 2007 09:43:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756234AbXD1Nkn (ORCPT ); Sat, 28 Apr 2007 09:40:43 -0400 Received: from nz-out-0506.google.com ([64.233.162.234]:45348 "EHLO nz-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756239AbXD1Nj6 (ORCPT ); Sat, 28 Apr 2007 09:39:58 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:cc:subject:in-reply-to:x-mailer:date:message-id:mime-version:content-type:reply-to:to:content-transfer-encoding:from; b=Av3UVSR9iEcBRV1YhXMMe6PSNKgogu1iVTyY8wosIp7yuWFuv9+eK95nqez4qJJGrIi12l4PDA8Edxf3uH4Osw0j6Thx5mOq+Mip0XIaug4hUxIFnpdSC+m53+BhIoIwPX9TLEUUl/eP4oGBXLybqVv34pQIoo8cfK3FZ1KLq0Q= Cc: Tejun Heo Subject: [PATCH 14/21] sysfs: implement kobj_sysfs_assoc_lock In-Reply-To: <11777675753460-git-send-email-htejun@gmail.com> X-Mailer: git-send-email Date: Sat, 28 Apr 2007 22:39:42 +0900 Message-Id: <11777675821170-git-send-email-htejun@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Reply-To: Tejun Heo To: gregkh@suse.de, dmitry.torokhov@gmail.com, cornelia.huck@de.ibm.com, oneukum@suse.de, rpurdie@rpsys.net, stern@rowland.harvard.edu, maneesh@in.ibm.com, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, htejun@gmail.com Content-Transfer-Encoding: 7BIT From: Tejun Heo Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org kobj->dentry can go away anytime unless the user controls when the associated sysfs node is deleted. This patch implements kobj_sysfs_assoc_lock which protects kobj->dentry. This will be used to maintain kobj based API when converting sysfs to use sysfs_dirent tree instead of dentry/kobject. Note that this lock belongs to kobject/driver-model not sysfs. Once sysfs is converted to not use kobject in its interface, this can be removed from sysfs. This is in preparation of object reference simplification. Signed-off-by: Tejun Heo --- fs/sysfs/dir.c | 8 +++++++- fs/sysfs/sysfs.h | 1 + 2 files changed, 8 insertions(+), 1 deletions(-) diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 0050de9..2fddf8a 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -14,6 +14,7 @@ #include "sysfs.h" DECLARE_RWSEM(sysfs_rename_sem); +spinlock_t kobj_sysfs_assoc_lock = SPIN_LOCK_UNLOCKED; static spinlock_t sysfs_ino_lock = SPIN_LOCK_UNLOCKED; static DEFINE_IDA(sysfs_ino_ida); @@ -408,8 +409,13 @@ static void __sysfs_remove_dir(struct dentry *dentry) void sysfs_remove_dir(struct kobject * kobj) { - __sysfs_remove_dir(kobj->dentry); + struct dentry *d = kobj->dentry; + + spin_lock(&kobj_sysfs_assoc_lock); kobj->dentry = NULL; + spin_unlock(&kobj_sysfs_assoc_lock); + + __sysfs_remove_dir(d); } int sysfs_rename_dir(struct kobject * kobj, struct dentry *new_parent, diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h index 14ca866..e37b6e8 100644 --- a/fs/sysfs/sysfs.h +++ b/fs/sysfs/sysfs.h @@ -61,6 +61,7 @@ extern void sysfs_remove_subdir(struct dentry *); extern void sysfs_drop_dentry(struct sysfs_dirent *sd, struct dentry *parent); extern int sysfs_setattr(struct dentry *dentry, struct iattr *iattr); +extern spinlock_t kobj_sysfs_assoc_lock; extern struct rw_semaphore sysfs_rename_sem; extern struct super_block * sysfs_sb; extern const struct file_operations sysfs_dir_operations; -- 1.5.0.3