/* all accesses are serialized by namespace_sem */
static struct user_namespace *user_ns;
-static struct mount *last_dest, *last_source, *dest_master;
+static struct mount *last_dest, *first_source, *last_source, *dest_master;
static struct mountpoint *mp;
static struct hlist_head *list;
+static inline bool peers(struct mount *m1, struct mount *m2)
+{
+ return m1->mnt_group_id == m2->mnt_group_id && m1->mnt_group_id;
+}
+
static int propagate_one(struct mount *m)
{
struct mount *child;
/* skip if mountpoint isn't covered by it */
if (!is_subdir(mp->m_dentry, m->mnt.mnt_root))
return 0;
- if (m->mnt_group_id == last_dest->mnt_group_id) {
+ if (peers(m, last_dest)) {
type = CL_MAKE_SHARED;
} else {
struct mount *n, *p;
+ bool done;
for (n = m; ; n = p) {
p = n->mnt_master;
- if (p == dest_master || IS_MNT_MARKED(p)) {
- while (last_dest->mnt_master != p) {
- last_source = last_source->mnt_master;
- last_dest = last_source->mnt_parent;
- }
- if (n->mnt_group_id != last_dest->mnt_group_id) {
- last_source = last_source->mnt_master;
- last_dest = last_source->mnt_parent;
- }
+ if (p == dest_master || IS_MNT_MARKED(p))
break;
- }
}
+ do {
+ struct mount *parent = last_source->mnt_parent;
+ if (last_source == first_source)
+ break;
+ done = parent->mnt_master == p;
+ if (done && peers(n, parent))
+ break;
+ last_source = last_source->mnt_master;
+ } while (!done);
+
type = CL_SLAVE;
/* beginning of peer group among the slaves? */
if (IS_MNT_SHARED(m))
*/
user_ns = current->nsproxy->mnt_ns->user_ns;
last_dest = dest_mnt;
+ first_source = source_mnt;
last_source = source_mnt;
mp = dest_mp;
list = tree_list;
__propagate_umount(mnt);
return 0;
}
+
+/*
+ * Iterates over all slaves, and slaves of slaves.
+ */
+static struct mount *next_descendent(struct mount *root, struct mount *cur)
+{
+ if (!IS_MNT_NEW(cur) && !list_empty(&cur->mnt_slave_list))
+ return first_slave(cur);
+ do {
+ if (cur->mnt_slave.next != &cur->mnt_master->mnt_slave_list)
+ return next_slave(cur);
+ cur = cur->mnt_master;
+ } while (cur != root);
+ return NULL;
+}
+
+void propagate_remount(struct mount *mnt)
+{
+ struct mount *m = mnt;
+ struct super_block *sb = mnt->mnt.mnt_sb;
+
+ if (sb->s_op->copy_mnt_data) {
+ m = next_descendent(mnt, m);
+ while (m) {
+ sb->s_op->copy_mnt_data(m->mnt.data, mnt->mnt.data);
+ m = next_descendent(mnt, m);
+ }
+ }
+}