int configfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
{
int ret;
struct path path;
struct configfs_dirent *sd;
struct config_item *parent_item;
struct config_item *target_item = NULL;
struct config_item_type *type;
ret = -EPERM; /* What lack-of-symlink returns */
if (dentry->d_parent == configfs_sb->s_root)
goto out;
sd = dentry->d_parent->d_fsdata;
/*
* Fake invisibility if dir belongs to a group/default groups hierarchy
* being attached
*/
ret = -ENOENT;
if (!configfs_dirent_is_ready(sd))
goto out;
parent_item = configfs_get_config_item(dentry->d_parent);
type = parent_item->ci_type;
ret = -EPERM;
if (!type || !type->ct_item_ops ||
!type->ct_item_ops->allow_link)
goto out_put;
ret = get_target(symname, &path, &target_item);
if (ret)
goto out_put;
ret = type->ct_item_ops->allow_link(parent_item, target_item);
if (!ret) {
mutex_lock(&configfs_symlink_mutex);
ret = create_link(parent_item, target_item, dentry);
mutex_unlock(&configfs_symlink_mutex);
if (ret && type->ct_item_ops->drop_link)
type->ct_item_ops->drop_link(parent_item,
target_item);
}
config_item_put(target_item);
path_put(&path);
out_put:
config_item_put(parent_item);
out:
return ret;
}
int configfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
{
int ret;
struct path path;
struct configfs_dirent *sd;
struct config_item *parent_item;
struct config_item *target_item = NULL;
struct config_item_type *type;
sd = dentry->d_parent->d_fsdata;
/*
*/
ret = -ENOENT;
if (!configfs_dirent_is_ready(sd))
goto out;
parent_item = configfs_get_config_item(dentry->d_parent);
type = parent_item->ci_type;
ret = -EPERM;
if (!type || !type->ct_item_ops ||
!type->ct_item_ops->allow_link)
goto out_put;
ret = get_target(symname, &path, &target_item, dentry->d_sb);
if (ret)
goto out_put;
ret = type->ct_item_ops->allow_link(parent_item, target_item);
if (!ret) {
mutex_lock(&configfs_symlink_mutex);
ret = create_link(parent_item, target_item, dentry);
mutex_unlock(&configfs_symlink_mutex);
if (ret && type->ct_item_ops->drop_link)
type->ct_item_ops->drop_link(parent_item,
target_item);
}
config_item_put(target_item);
path_put(&path);
out_put:
config_item_put(parent_item);
out:
return ret;
}
static int create_link(struct config_item *parent_item,
struct config_item *item,
struct dentry *dentry)
{
struct configfs_dirent *target_sd = item->ci_dentry->d_fsdata;
struct configfs_symlink *sl;
int ret;
ret = -ENOENT;
if (!configfs_dirent_is_ready(target_sd))
goto out;
ret = -ENOMEM;
sl = kmalloc(sizeof(struct configfs_symlink), GFP_KERNEL);
if (sl) {
sl->sl_target = config_item_get(item);
spin_lock(&configfs_dirent_lock);
if (target_sd->s_type & CONFIGFS_USET_DROPPING) {
spin_unlock(&configfs_dirent_lock);
config_item_put(item);
kfree(sl);
return -ENOENT;
}
list_add(&sl->sl_list, &target_sd->s_links);
spin_unlock(&configfs_dirent_lock);
ret = configfs_create_link(sl, parent_item->ci_dentry,
dentry);
if (ret) {
spin_lock(&configfs_dirent_lock);
list_del_init(&sl->sl_list);
spin_unlock(&configfs_dirent_lock);
config_item_put(item);
kfree(sl);
}
}
out:
return ret;
}
