aboutsummaryrefslogtreecommitdiffstats
path: root/fs
diff options
context:
space:
mode:
Diffstat (limited to 'fs')
-rw-r--r--fs/namespace.c42
-rw-r--r--fs/pnode.h2
2 files changed, 33 insertions, 11 deletions
diff --git a/fs/namespace.c b/fs/namespace.c
index c7cb8a526c05..2b8aa15fd6df 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1361,6 +1361,36 @@ enum umount_tree_flags {
UMOUNT_PROPAGATE = 2,
UMOUNT_CONNECTED = 4,
};
+
+static bool disconnect_mount(struct mount *mnt, enum umount_tree_flags how)
+{
+ /* Leaving mounts connected is only valid for lazy umounts */
+ if (how & UMOUNT_SYNC)
+ return true;
+
+ /* A mount without a parent has nothing to be connected to */
+ if (!mnt_has_parent(mnt))
+ return true;
+
+ /* Because the reference counting rules change when mounts are
+ * unmounted and connected, umounted mounts may not be
+ * connected to mounted mounts.
+ */
+ if (!(mnt->mnt_parent->mnt.mnt_flags & MNT_UMOUNT))
+ return true;
+
+ /* Has it been requested that the mount remain connected? */
+ if (how & UMOUNT_CONNECTED)
+ return false;
+
+ /* Is the mount locked such that it needs to remain connected? */
+ if (IS_MNT_LOCKED(mnt))
+ return false;
+
+ /* By default disconnect the mount */
+ return true;
+}
+
/*
* mount_lock must be held
* namespace_sem must be held for write
@@ -1398,10 +1428,7 @@ static void umount_tree(struct mount *mnt, enum umount_tree_flags how)
if (how & UMOUNT_SYNC)
p->mnt.mnt_flags |= MNT_SYNC_UMOUNT;
- disconnect = !(((how & UMOUNT_CONNECTED) &&
- mnt_has_parent(p) &&
- (p->mnt_parent->mnt.mnt_flags & MNT_UMOUNT)) ||
- IS_MNT_LOCKED_AND_LAZY(p));
+ disconnect = disconnect_mount(p, how);
pin_insert_group(&p->mnt_umount, &p->mnt_parent->mnt,
disconnect ? &unmounted : NULL);
@@ -1538,11 +1565,8 @@ void __detach_mounts(struct dentry *dentry)
while (!hlist_empty(&mp->m_list)) {
mnt = hlist_entry(mp->m_list.first, struct mount, mnt_mp_list);
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);
- }
+ hlist_add_head(&mnt->mnt_umount.s_list, &unmounted);
+ umount_mnt(mnt);
}
else umount_tree(mnt, UMOUNT_CONNECTED);
}
diff --git a/fs/pnode.h b/fs/pnode.h
index 7114ce6e6b9e..0fcdbe7ca648 100644
--- a/fs/pnode.h
+++ b/fs/pnode.h
@@ -20,8 +20,6 @@
#define SET_MNT_MARK(m) ((m)->mnt.mnt_flags |= MNT_MARKED)
#define CLEAR_MNT_MARK(m) ((m)->mnt.mnt_flags &= ~MNT_MARKED)
#define IS_MNT_LOCKED(m) ((m)->mnt.mnt_flags & MNT_LOCKED)
-#define IS_MNT_LOCKED_AND_LAZY(m) \
- (((m)->mnt.mnt_flags & (MNT_LOCKED|MNT_SYNC_UMOUNT)) == MNT_LOCKED)
#define CL_EXPIRE 0x01
#define CL_SLAVE 0x02