switch unlock_mount() to namespace_unlock(), convert all umount_tree() callers

which allows to kill the last argument of umount_tree() and make release_mounts()
static.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

3 files changed, 16 insertions, 24 deletions

diff --git a/fs/namespace.c b/fs/namespace.c
index 7563270a43ab..fa93d54d21e8 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1121,7 +1121,7 @@ EXPORT_SYMBOL(may_umount);
 
 static LIST_HEAD(unmounted);    /* protected by namespace_sem */
 
-void release_mounts(struct list_head *head)
+static void release_mounts(struct list_head *head)
 {
         struct mount *mnt;
         while (!list_empty(head)) {
@@ -1157,7 +1157,7 @@ static void namespace_unlock(void)
  * vfsmount lock must be held for write
  * namespace_sem must be held for write
  */
-void umount_tree(struct mount *mnt, int propagate, struct list_head *kill)
+void umount_tree(struct mount *mnt, int propagate)
 {
         LIST_HEAD(tmp_list);
         struct mount *p;
@@ -1181,7 +1181,7 @@ void umount_tree(struct mount *mnt, int propagate, struct list_head *kill)
                 }
                 change_mnt_propagation(p, MS_PRIVATE);
         }
-        list_splice(&tmp_list, kill);
+        list_splice(&tmp_list, &unmounted);
 }
 
 static void shrink_submounts(struct mount *mnt);
@@ -1190,7 +1190,6 @@ static int do_umount(struct mount *mnt, int flags)
 {
         struct super_block *sb = mnt->mnt.mnt_sb;
         int retval;
-        LIST_HEAD(umount_list);
 
         retval = security_sb_umount(&mnt->mnt, flags);
         if (retval)
@@ -1267,7 +1266,7 @@ static int do_umount(struct mount *mnt, int flags)
         retval = -EBUSY;
         if (flags & MNT_DETACH || !propagate_mount_busy(mnt, 2)) {
                 if (!list_empty(&mnt->mnt_list))
-                        umount_tree(mnt, 1, &unmounted);
+                        umount_tree(mnt, 1);
                 retval = 0;
         }
         br_write_unlock(&vfsmount_lock);
@@ -1401,11 +1400,9 @@ struct mount *copy_tree(struct mount *mnt, struct dentry *dentry,
         return res;
 out:
         if (res) {
-                LIST_HEAD(umount_list);
                 br_write_lock(&vfsmount_lock);
-                umount_tree(res, 0, &umount_list);
+                umount_tree(res, 0);
                 br_write_unlock(&vfsmount_lock);
-                release_mounts(&umount_list);
         }
         return q;
 }
@@ -1418,7 +1415,7 @@ struct vfsmount *collect_mounts(struct path *path)
         down_write(&namespace_sem);
         tree = copy_tree(real_mount(path->mnt), path->dentry,
                          CL_COPY_ALL | CL_PRIVATE);
-        up_write(&namespace_sem);
+        namespace_unlock();
         if (IS_ERR(tree))
                 return NULL;
         return &tree->mnt;
@@ -1428,7 +1425,7 @@ void drop_collected_mounts(struct vfsmount *mnt)
 {
         down_write(&namespace_sem);
         br_write_lock(&vfsmount_lock);
-        umount_tree(real_mount(mnt), 0, &unmounted);
+        umount_tree(real_mount(mnt), 0);
         br_write_unlock(&vfsmount_lock);
         namespace_unlock();
 }
@@ -1619,7 +1616,7 @@ static void unlock_mount(struct mountpoint *where)
 {
         struct dentry *dentry = where->m_dentry;
         put_mountpoint(where);
-        up_write(&namespace_sem);
+        namespace_unlock();
         mutex_unlock(&dentry->d_inode->i_mutex);
 }
 
@@ -1693,7 +1690,6 @@ static int do_change_type(struct path *path, int flag)
 static int do_loopback(struct path *path, const char *old_name,
                                 int recurse)
 {
-        LIST_HEAD(umount_list);
         struct path old_path;
         struct mount *mnt = NULL, *old, *parent;
         struct mountpoint *mp;
@@ -1736,12 +1732,11 @@ static int do_loopback(struct path *path, const char *old_name,
         err = graft_tree(mnt, parent, mp);
         if (err) {
                 br_write_lock(&vfsmount_lock);
-                umount_tree(mnt, 0, &umount_list);
+                umount_tree(mnt, 0);
                 br_write_unlock(&vfsmount_lock);
         }
 out2:
         unlock_mount(mp);
-        release_mounts(&umount_list);
 out:
         path_put(&old_path);
         return err;
@@ -2080,7 +2075,7 @@ void mark_mounts_for_expiry(struct list_head *mounts)
         while (!list_empty(&graveyard)) {
                 mnt = list_first_entry(&graveyard, struct mount, mnt_expire);
                 touch_mnt_namespace(mnt->mnt_ns);
-                umount_tree(mnt, 1, &unmounted);
+                umount_tree(mnt, 1);
         }
         br_write_unlock(&vfsmount_lock);
         namespace_unlock();
@@ -2151,7 +2146,7 @@ static void shrink_submounts(struct mount *mnt)
                         m = list_first_entry(&graveyard, struct mount,
                                                 mnt_expire);
                         touch_mnt_namespace(m->mnt_ns);
-                        umount_tree(m, 1, &unmounted);
+                        umount_tree(m, 1);
                 }
         }
 }
@@ -2385,7 +2380,7 @@ static struct mnt_namespace *dup_mnt_ns(struct mnt_namespace *mnt_ns,
                 copy_flags |= CL_SHARED_TO_SLAVE;
         new = copy_tree(old, old->mnt.mnt_root, copy_flags);
         if (IS_ERR(new)) {
-                up_write(&namespace_sem);
+                namespace_unlock();
                 free_mnt_ns(new_ns);
                 return ERR_CAST(new);
         }
@@ -2416,7 +2411,7 @@ static struct mnt_namespace *dup_mnt_ns(struct mnt_namespace *mnt_ns,
                 p = next_mnt(p, old);
                 q = next_mnt(q, new);
         }
-        up_write(&namespace_sem);
+        namespace_unlock();
 
         if (rootmnt)
                 mntput(rootmnt);
@@ -2740,7 +2735,7 @@ void put_mnt_ns(struct mnt_namespace *ns)
                 return;
         down_write(&namespace_sem);
         br_write_lock(&vfsmount_lock);
-        umount_tree(ns->root, 0, &unmounted);
+        umount_tree(ns->root, 0);
         br_write_unlock(&vfsmount_lock);
         namespace_unlock();
         free_mnt_ns(ns);
diff --git a/fs/pnode.c b/fs/pnode.c
index 98e0d3a23fac..43617258fa6a 100644
--- a/fs/pnode.c
+++ b/fs/pnode.c
@@ -225,7 +225,6 @@ int propagate_mnt(struct mount *dest_mnt, struct mountpoint *dest_mp,
         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)) {
@@ -261,10 +260,9 @@ 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);
+                umount_tree(child, 0);
         }
         br_write_unlock(&vfsmount_lock);
-        release_mounts(&umount_list);
         return ret;
 }
 
diff --git a/fs/pnode.h b/fs/pnode.h
index f4357d3a0a44..9eb00ee65bbe 100644
--- a/fs/pnode.h
+++ b/fs/pnode.h
@@ -40,8 +40,7 @@ int get_dominating_id(struct mount *mnt, const struct path *root);
 unsigned int mnt_get_count(struct mount *mnt);
 void mnt_set_mountpoint(struct mount *, struct mountpoint *,
                         struct mount *);
-void release_mounts(struct list_head *);
-void umount_tree(struct mount *, int, struct list_head *);
+void umount_tree(struct mount *, int);
 struct mount *copy_tree(struct mount *, struct dentry *, int);
 bool is_path_reachable(struct mount *, struct dentry *,
                          const struct path *root);