vfs: new internal helper: mnt_has_parent(mnt)

[karo-tx-linux.git] / fs / namespace.c

diff --git a/fs/namespace.c b/fs/namespace.c
index 31d357450f7fc0bf247bb53afd1f200bd0b3cb2a..ec8512478b04fff1697bd9fb058176f5e67b4144 100644 (file)
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1182,7 +1182,7 @@ void release_mounts(struct list_head *head)
        while (!list_empty(head)) {
                mnt = list_first_entry(head, struct vfsmount, mnt_hash);
                list_del_init(&mnt->mnt_hash);
-               if (mnt->mnt_parent != mnt) {
+               if (mnt_has_parent(mnt)) {
                        struct dentry *dentry;
                        struct vfsmount *m;
 
@@ -1222,7 +1222,7 @@ void umount_tree(struct vfsmount *mnt, int propagate, struct list_head *kill)
                p->mnt_ns = NULL;
                __mnt_make_shortterm(p);
                list_del_init(&p->mnt_child);
-               if (p->mnt_parent != p) {
+               if (mnt_has_parent(p)) {
                        p->mnt_parent->mnt_ghosts++;
                        dentry_reset_mounted(p->mnt_parent, p->mnt_mountpoint);
                }
@@ -1867,7 +1867,7 @@ static int do_move_mount(struct path *path, char *old_name)
        if (old_path.dentry != old_path.mnt->mnt_root)
                goto out1;
 
-       if (old_path.mnt == old_path.mnt->mnt_parent)
+       if (!mnt_has_parent(old_path.mnt))
                goto out1;
 
        if (S_ISDIR(path->dentry->d_inode->i_mode) !=
@@ -1887,7 +1887,7 @@ static int do_move_mount(struct path *path, char *old_name)
            tree_contains_unbindable(old_path.mnt))
                goto out1;
        err = -ELOOP;
-       for (p = path->mnt; p->mnt_parent != p; p = p->mnt_parent)
+       for (p = path->mnt; mnt_has_parent(p); p = p->mnt_parent)
                if (p == old_path.mnt)
                        goto out1;
 
@@ -2604,17 +2604,17 @@ SYSCALL_DEFINE2(pivot_root, const char __user *, new_root,
        error = -EINVAL;
        if (root.mnt->mnt_root != root.dentry)
                goto out4; /* not a mountpoint */
-       if (root.mnt->mnt_parent == root.mnt)
+       if (!mnt_has_parent(root.mnt))
                goto out4; /* not attached */
        if (new.mnt->mnt_root != new.dentry)
                goto out4; /* not a mountpoint */
-       if (new.mnt->mnt_parent == new.mnt)
+       if (!mnt_has_parent(new.mnt))
                goto out4; /* not attached */
        /* make sure we can reach put_old from new_root */
        tmp = old.mnt;
        if (tmp != new.mnt) {
                for (;;) {
-                       if (tmp->mnt_parent == tmp)
+                       if (!mnt_has_parent(tmp))
                                goto out4; /* already mounted on put_old */
                        if (tmp->mnt_parent == new.mnt)
                                break;