/*
* mount 'source_mnt' under the destination 'dest_mnt' at
* dentry 'dest_dentry'. And propagate that mount to
* all the peer and slave mounts of 'dest_mnt'.
* Link all the new mounts into a propagation tree headed at
* source_mnt. Also link all the new mounts using ->mnt_list
* headed at source_mnt's ->mnt_list
*
* @dest_mnt: destination mount.
* @dest_dentry: destination dentry.
* @source_mnt: source mount.
* @tree_list : list of heads of trees to be attached.
*/
int propagate_mnt(struct mount *dest_mnt, struct dentry *dest_dentry,
struct mount *source_mnt, struct list_head *tree_list)
{
struct user_namespace *user_ns = current->nsproxy->mnt_ns->user_ns;
struct mount *m, *child;
int ret = 0;
struct mount *prev_dest_mnt = dest_mnt;
struct mount *prev_src_mnt = source_mnt;
LIST_HEAD(tmp_list);
LIST_HEAD(umount_list);
for (m = propagation_next(dest_mnt, dest_mnt); m;
m = propagation_next(m, dest_mnt)) {
int type;
struct mount *source;
if (IS_MNT_NEW(m))
continue;
source = get_source(m, prev_dest_mnt, prev_src_mnt, &type);
/* Notice when we are propagating across user namespaces */
if (m->mnt_ns->user_ns != user_ns)
type |= CL_UNPRIVILEGED;
child = copy_tree(source, source->mnt.mnt_root, type);
if (IS_ERR(child)) {
ret = PTR_ERR(child);
list_splice(tree_list, tmp_list.prev);
goto out;
}
if (is_subdir(dest_dentry, m->mnt.mnt_root)) {
mnt_set_mountpoint(m, dest_dentry, child);
list_add_tail(&child->mnt_hash, tree_list);
} else {
/*
* This can happen if the parent mount was bind mounted
* on some subdirectory of a shared/slave mount.
*/
list_add_tail(&child->mnt_hash, &tmp_list);
}
prev_dest_mnt = m;
prev_src_mnt = child;
}
out:
br_write_lock(&vfsmount_lock);
while (!list_empty(&tmp_list)) {
child = list_first_entry(&tmp_list, struct mount, mnt_hash);
umount_tree(child, 0, &umount_list);
}
br_write_unlock(&vfsmount_lock);
release_mounts(&umount_list);
return ret;
}
int propagate_mnt(struct mount *dest_mnt, struct dentry *dest_dentry,
struct mount *source_mnt, struct list_head *tree_list)
{
struct mount *m, *child;
int ret = 0;
struct mount *prev_dest_mnt = dest_mnt;
struct mount *prev_src_mnt = source_mnt;
LIST_HEAD(tmp_list);
LIST_HEAD(umount_list);
for (m = propagation_next(dest_mnt, dest_mnt); m;
m = propagation_next(m, dest_mnt)) {
int type;
struct mount *source;
if (IS_MNT_NEW(m))
continue;
source = get_source(m, prev_dest_mnt, prev_src_mnt, &type);
if (!(child = copy_tree(source, source->mnt.mnt_root, type))) {
ret = -ENOMEM;
list_splice(tree_list, tmp_list.prev);
goto out;
}
if (is_subdir(dest_dentry, m->mnt.mnt_root)) {
mnt_set_mountpoint(m, dest_dentry, child);
list_add_tail(&child->mnt_hash, tree_list);
} else {
list_add_tail(&child->mnt_hash, &tmp_list);
}
prev_dest_mnt = m;
prev_src_mnt = child;
}
out:
br_write_lock(vfsmount_lock);
while (!list_empty(&tmp_list)) {
child = list_first_entry(&tmp_list, struct mount, mnt_hash);
umount_tree(child, 0, &umount_list);
}
br_write_unlock(vfsmount_lock);
release_mounts(&umount_list);
return ret;
}
/* This returns 0 if everything went fine.
* It will return 1 if the group was killed as a result.
* A negative return indicates failure.
*
* The RTNL lock must be held.
*/
static int unregister_vlan_dev(struct net_device *real_dev,
unsigned short vlan_id)
{
struct net_device *dev = NULL;
int real_dev_ifindex = real_dev->ifindex;
struct vlan_group *grp;
int i, ret;
#ifdef VLAN_DEBUG
printk(VLAN_DBG "%s: VID: %i\n", __FUNCTION__, vlan_id);
#endif
/* sanity check */
if (vlan_id >= VLAN_VID_MASK)
return -EINVAL;
spin_lock_bh(&vlan_group_lock);
grp = __vlan_find_group(real_dev_ifindex);
spin_unlock_bh(&vlan_group_lock);
ret = 0;
if (grp) {
dev = grp->vlan_devices[vlan_id];
if (dev) {
/* Remove proc entry */
vlan_proc_rem_dev(dev);
/* Take it out of our own structures, but be sure to
* interlock with HW accelerating devices or SW vlan
* input packet processing.
*/
if (real_dev->features &
(NETIF_F_HW_VLAN_RX | NETIF_F_HW_VLAN_FILTER)) {
real_dev->vlan_rx_kill_vid(real_dev, vlan_id);
}
br_write_lock(BR_NETPROTO_LOCK);
grp->vlan_devices[vlan_id] = NULL;
br_write_unlock(BR_NETPROTO_LOCK);
/* Caller unregisters (and if necessary, puts)
* VLAN device, but we get rid of the reference to
* real_dev here.
*/
dev_put(real_dev);
/* If the group is now empty, kill off the
* group.
*/
for (i = 0; i < VLAN_VID_MASK; i++)
if (grp->vlan_devices[i])
break;
if (i == VLAN_VID_MASK) {
if (real_dev->features & NETIF_F_HW_VLAN_RX)
real_dev->vlan_rx_register(real_dev, NULL);
spin_lock_bh(&vlan_group_lock);
__grp_unhash(grp);
spin_unlock_bh(&vlan_group_lock);
/* Free the group, after we have removed it
* from the hash.
*/
kfree(grp);
grp = NULL;
ret = 1;
}
MOD_DEC_USE_COUNT;
}
}
return ret;
}