*/
struct mount *__lookup_mnt_last(struct vfsmount *mnt, struct dentry *dentry)
{
- struct mount *p, *res;
- res = p = __lookup_mnt(mnt, dentry);
+ struct mount *p, *res = NULL;
+ p = __lookup_mnt(mnt, dentry);
if (!p)
goto out;
+ if (!(p->mnt.mnt_flags & MNT_UMOUNT))
+ res = p;
hlist_for_each_entry_continue(p, mnt_hash) {
if (&p->mnt_parent->mnt != mnt || p->mnt_mountpoint != dentry)
break;
- res = p;
+ if (!(p->mnt.mnt_flags & MNT_UMOUNT))
+ res = p;
}
out:
return res;
/*
* vfsmount lock must be held for write
*/
-static void detach_mnt(struct mount *mnt, struct path *old_path)
+static void unhash_mnt(struct mount *mnt)
{
- old_path->dentry = mnt->mnt_mountpoint;
- old_path->mnt = &mnt->mnt_parent->mnt;
mnt->mnt_parent = mnt;
mnt->mnt_mountpoint = mnt->mnt.mnt_root;
list_del_init(&mnt->mnt_child);
mnt->mnt_mp = NULL;
}
+/*
+ * vfsmount lock must be held for write
+ */
+static void detach_mnt(struct mount *mnt, struct path *old_path)
+{
+ old_path->dentry = mnt->mnt_mountpoint;
+ old_path->mnt = &mnt->mnt_parent->mnt;
+ unhash_mnt(mnt);
+}
+
+/*
+ * vfsmount lock must be held for write
+ */
+static void umount_mnt(struct mount *mnt)
+{
+ /* old mountpoint will be dropped when we can do that */
+ mnt->mnt_ex_mountpoint = mnt->mnt_mountpoint;
+ unhash_mnt(mnt);
+}
+
/*
* vfsmount lock must be held for write
*/
rcu_read_unlock();
list_del(&mnt->mnt_instance);
+
+ if (unlikely(!list_empty(&mnt->mnt_mounts))) {
+ struct mount *p, *tmp;
+ list_for_each_entry_safe(p, tmp, &mnt->mnt_mounts, mnt_child) {
+ umount_mnt(p);
+ }
+ }
unlock_mount_hash();
if (likely(!(mnt->mnt.mnt_flags & MNT_INTERNAL))) {
enum umount_tree_flags {
UMOUNT_SYNC = 1,
UMOUNT_PROPAGATE = 2,
+ UMOUNT_CONNECTED = 4,
};
/*
* mount_lock must be held
*/
static void umount_tree(struct mount *mnt, enum umount_tree_flags how)
{
- HLIST_HEAD(tmp_list);
+ LIST_HEAD(tmp_list);
struct mount *p;
+ if (how & UMOUNT_PROPAGATE)
+ propagate_mount_unlock(mnt);
+
+ /* Gather the mounts to umount */
for (p = mnt; p; p = next_mnt(p, mnt)) {
- hlist_del_init_rcu(&p->mnt_hash);
- hlist_add_head(&p->mnt_hash, &tmp_list);
+ p->mnt.mnt_flags |= MNT_UMOUNT;
+ list_move(&p->mnt_list, &tmp_list);
}
- hlist_for_each_entry(p, &tmp_list, mnt_hash)
+ /* Hide the mounts from mnt_mounts */
+ list_for_each_entry(p, &tmp_list, mnt_list) {
list_del_init(&p->mnt_child);
+ }
+ /* Add propogated mounts to the tmp_list */
if (how & UMOUNT_PROPAGATE)
propagate_umount(&tmp_list);
- while (!hlist_empty(&tmp_list)) {
- p = hlist_entry(tmp_list.first, struct mount, mnt_hash);
- hlist_del_init_rcu(&p->mnt_hash);
+ while (!list_empty(&tmp_list)) {
+ bool disconnect;
+ p = list_first_entry(&tmp_list, struct mount, mnt_list);
list_del_init(&p->mnt_expire);
list_del_init(&p->mnt_list);
__touch_mnt_namespace(p->mnt_ns);
if (how & UMOUNT_SYNC)
p->mnt.mnt_flags |= MNT_SYNC_UMOUNT;
- pin_insert_group(&p->mnt_umount, &p->mnt_parent->mnt, &unmounted);
+ disconnect = !(((how & UMOUNT_CONNECTED) &&
+ mnt_has_parent(p) &&
+ (p->mnt_parent->mnt.mnt_flags & MNT_UMOUNT)) ||
+ IS_MNT_LOCKED_AND_LAZY(p));
+
+ pin_insert_group(&p->mnt_umount, &p->mnt_parent->mnt,
+ disconnect ? &unmounted : NULL);
if (mnt_has_parent(p)) {
- hlist_del_init(&p->mnt_mp_list);
- put_mountpoint(p->mnt_mp);
mnt_add_count(p->mnt_parent, -1);
- /* old mountpoint will be dropped when we can do that */
- p->mnt_ex_mountpoint = p->mnt_mountpoint;
- p->mnt_mountpoint = p->mnt.mnt_root;
- p->mnt_parent = p;
- p->mnt_mp = NULL;
+ if (!disconnect) {
+ /* Don't forget about p */
+ list_add_tail(&p->mnt_child, &p->mnt_parent->mnt_mounts);
+ } else {
+ umount_mnt(p);
+ }
}
change_mnt_propagation(p, MS_PRIVATE);
}
namespace_lock();
mp = lookup_mountpoint(dentry);
- if (!mp)
+ if (IS_ERR_OR_NULL(mp))
goto out_unlock;
lock_mount_hash();
while (!hlist_empty(&mp->m_list)) {
mnt = hlist_entry(mp->m_list.first, struct mount, mnt_mp_list);
- umount_tree(mnt, 0);
+ if (mnt->mnt.mnt_flags & MNT_UMOUNT) {
+ struct mount *p, *tmp;
+ list_for_each_entry_safe(p, tmp, &mnt->mnt_mounts, mnt_child) {
+ hlist_add_head(&p->mnt_umount.s_list, &unmounted);
+ umount_mnt(p);
+ }
+ }
+ else umount_tree(mnt, UMOUNT_CONNECTED);
}
unlock_mount_hash();
put_mountpoint(mp);
{
struct mount *tree;
namespace_lock();
- tree = copy_tree(real_mount(path->mnt), path->dentry,
- CL_COPY_ALL | CL_PRIVATE);
+ if (!check_mnt(real_mount(path->mnt)))
+ tree = ERR_PTR(-EINVAL);
+ else
+ tree = copy_tree(real_mount(path->mnt), path->dentry,
+ CL_COPY_ALL | CL_PRIVATE);
namespace_unlock();
if (IS_ERR(tree))
return ERR_CAST(tree);