From htejun@gmail.com Mon Aug 20 05:36:58 2007 From: Eric W. Biederman Date: Mon, 20 Aug 2007 21:36:31 +0900 Subject: [PATCH 14/14] sysfs: Rewrite sysfs_move_dir in terms of sysfs dirents To: ebiederm@xmission.com, cornelia.huck@de.ibm.com, greg@kroah.com, linux-kernel@vger.kernel.org, satyam@infradead.org, stern@rowland.harvard.edu, containers@lists.osdl.org, htejun@gmail.com Cc: Eric W. Biederman , Tejun Heo Message-ID: <11876133911799-git-send-email-htejun@gmail.com> From: Eric W. Biederman This patch rewrites sysfs_move_dir to perform it's checks as much as possible on the underlying sysfs_dirents instead of the contents of the dcache, making sysfs_move_dir more like the rest of the sysfs directory modification code. Signed-off-by: Eric W. Biederman Signed-off-by: Tejun Heo Cc: Cornelia Huck Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 34 ++++++++++++++++++---------------- 1 file changed, 18 insertions(+), 16 deletions(-) --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -845,56 +845,58 @@ int sysfs_move_dir(struct kobject *kobj, BUG_ON(!sd->s_parent); new_parent_sd = new_parent_kobj->sd ? new_parent_kobj->sd : &sysfs_root; + error = 0; + if (sd->s_parent == new_parent_sd) + goto out; /* nothing to move */ + /* get dentries */ old_dentry = sysfs_get_dentry(sd); if (IS_ERR(old_dentry)) { error = PTR_ERR(old_dentry); - goto out_dput; + goto out; } old_parent = old_dentry->d_parent; new_parent = sysfs_get_dentry(new_parent_sd); if (IS_ERR(new_parent)) { error = PTR_ERR(new_parent); - goto out_dput; + goto out; } - if (old_parent->d_inode == new_parent->d_inode) { - error = 0; - goto out_dput; /* nothing to move */ - } again: mutex_lock(&old_parent->d_inode->i_mutex); if (!mutex_trylock(&new_parent->d_inode->i_mutex)) { mutex_unlock(&old_parent->d_inode->i_mutex); goto again; } + mutex_lock(&sysfs_mutex); - new_dentry = lookup_one_len(kobject_name(kobj), new_parent, strlen(kobject_name(kobj))); - if (IS_ERR(new_dentry)) { - error = PTR_ERR(new_dentry); + error = -EEXIST; + if (sysfs_find_dirent(new_parent_sd, sd->s_name)) goto out_unlock; - } else - error = 0; + + error = -ENOMEM; + new_dentry = d_alloc_name(new_parent, sd->s_name); + if (!new_dentry) + goto out_unlock; + + error = 0; d_add(new_dentry, NULL); d_move(old_dentry, new_dentry); dput(new_dentry); /* Remove from old parent's list and insert into new parent's list. */ - mutex_lock(&sysfs_mutex); - sysfs_unlink_sibling(sd); sysfs_get(new_parent_sd); sysfs_put(sd->s_parent); sd->s_parent = new_parent_sd; sysfs_link_sibling(sd); - mutex_unlock(&sysfs_mutex); - out_unlock: + mutex_unlock(&sysfs_mutex); mutex_unlock(&new_parent->d_inode->i_mutex); mutex_unlock(&old_parent->d_inode->i_mutex); - out_dput: + out: dput(new_parent); dput(old_dentry); dput(new_dentry);