sysfs: Rewrite sysfs_move_dir in terms of sysfs dirents

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 <ebiederm@xmission.com>
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Eric W. Biederman 2007-08-20 21:36:31 +09:00 committed by Greg Kroah-Hartman
parent 9918f9a481
commit 45aaae9c51

View File

@ -845,56 +845,58 @@ int sysfs_move_dir(struct kobject *kobj, struct kobject *new_parent_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);