diff options
| author | Eric W. Biederman <ebiederm@xmission.com> | 2014-12-18 13:10:48 -0600 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-05-06 22:03:50 +0200 |
| commit | 953bab2cb35f8f6f2a0183c1b27ff7466f72bccc (patch) | |
| tree | c6bc8b5f2f0424324173ceca56243a32302c0605 /fs/namespace.c | |
| parent | a15f7b5e276d1b8f71d3d64d7f3f509e77bee5e4 (diff) | |
mnt: In umount_tree reuse mnt_list instead of mnt_hash
commit c003b26ff98ca04a180ff34c38c007a3998d62f9 upstream.
umount_tree builds a list of mounts that need to be unmounted.
Utilize mnt_list for this purpose instead of mnt_hash. This begins to
allow keeping a mount on the mnt_hash after it is unmounted, which is
necessary for a properly functioning MNT_LOCKED implementation.
The fact that mnt_list is an ordinary list makding available list_move
is nice bonus.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/namespace.c')
| -rw-r--r-- | fs/namespace.c | 20 |
1 files changed, 11 insertions, 9 deletions
diff --git a/fs/namespace.c b/fs/namespace.c index 616a694391d6..18df0af605ba 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1329,23 +1329,25 @@ enum umount_tree_flags { */ static void umount_tree(struct mount *mnt, enum umount_tree_flags how) { - HLIST_HEAD(tmp_list); + LIST_HEAD(tmp_list); struct mount *p; - for (p = mnt; p; p = next_mnt(p, mnt)) { - hlist_del_init_rcu(&p->mnt_hash); - hlist_add_head(&p->mnt_hash, &tmp_list); - } + /* Gather the mounts to umount */ + for (p = mnt; p; p = next_mnt(p, mnt)) + list_move(&p->mnt_list, &tmp_list); - hlist_for_each_entry(p, &tmp_list, mnt_hash) + /* Hide the mounts from lookup_mnt and mnt_mounts */ + list_for_each_entry(p, &tmp_list, mnt_list) { + hlist_del_init_rcu(&p->mnt_hash); 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)) { + 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); |