vfs: spread struct mount - mnt_has_parent
Al Viro [Fri, 25 Nov 2011 02:47:05 +0000 (21:47 -0500)]
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/dcache.c
fs/mount.h
fs/namespace.c

index 64c8ce4..1834e71 100644 (file)
@@ -2460,8 +2460,9 @@ static int prepend_path(const struct path *path,
                struct dentry * parent;
 
                if (dentry == vfsmnt->mnt_root || IS_ROOT(dentry)) {
+                       struct mount *mnt = real_mount(vfsmnt);
                        /* Global root? */
-                       if (!mnt_has_parent(vfsmnt))
+                       if (!mnt_has_parent(mnt))
                                goto global_root;
                        dentry = vfsmnt->mnt_mountpoint;
                        vfsmnt = vfsmnt->mnt_parent;
index 831e7c8..541daf5 100644 (file)
@@ -10,9 +10,9 @@ static inline struct mount *real_mount(struct vfsmount *mnt)
        return container_of(mnt, struct mount, mnt);
 }
 
-static inline int mnt_has_parent(struct vfsmount *mnt)
+static inline int mnt_has_parent(struct mount *mnt)
 {
-       return mnt != mnt->mnt_parent;
+       return &mnt->mnt != mnt->mnt.mnt_parent;
 }
 
 extern struct mount *__lookup_mnt(struct vfsmount *, struct dentry *, int);
index 17927f9..ced3aa5 100644 (file)
@@ -1195,7 +1195,7 @@ void release_mounts(struct list_head *head)
        while (!list_empty(head)) {
                mnt = list_first_entry(head, struct mount, mnt_hash);
                list_del_init(&mnt->mnt_hash);
-               if (mnt_has_parent(&mnt->mnt)) {
+               if (mnt_has_parent(mnt)) {
                        struct dentry *dentry;
                        struct vfsmount *m;
 
@@ -1235,7 +1235,7 @@ void umount_tree(struct mount *mnt, int propagate, struct list_head *kill)
                p->mnt.mnt_ns = NULL;
                __mnt_make_shortterm(&p->mnt);
                list_del_init(&p->mnt.mnt_child);
-               if (mnt_has_parent(&p->mnt)) {
+               if (mnt_has_parent(p)) {
                        p->mnt.mnt_parent->mnt_ghosts++;
                        dentry_reset_mounted(p->mnt.mnt_mountpoint);
                }
@@ -1861,7 +1861,7 @@ static inline int tree_contains_unbindable(struct mount *mnt)
 static int do_move_mount(struct path *path, char *old_name)
 {
        struct path old_path, parent_path;
-       struct vfsmount *p;
+       struct mount *p;
        struct mount *old;
        int err = 0;
        if (!capable(CAP_SYS_ADMIN))
@@ -1889,7 +1889,7 @@ static int do_move_mount(struct path *path, char *old_name)
 
        old = real_mount(old_path.mnt);
 
-       if (!mnt_has_parent(old_path.mnt))
+       if (!mnt_has_parent(old))
                goto out1;
 
        if (S_ISDIR(path->dentry->d_inode->i_mode) !=
@@ -1908,8 +1908,8 @@ static int do_move_mount(struct path *path, char *old_name)
            tree_contains_unbindable(old))
                goto out1;
        err = -ELOOP;
-       for (p = path->mnt; mnt_has_parent(p); p = p->mnt_parent)
-               if (p == old_path.mnt)
+       for (p = real_mount(path->mnt); mnt_has_parent(p); p = real_mount(p->mnt.mnt_parent))
+               if (p == old)
                        goto out1;
 
        err = attach_recursive_mnt(old, path, &parent_path);
@@ -2562,7 +2562,7 @@ out_type:
 bool is_path_reachable(struct vfsmount *mnt, struct dentry *dentry,
                         const struct path *root)
 {
-       while (mnt != root->mnt && mnt_has_parent(mnt)) {
+       while (mnt != root->mnt && mnt_has_parent(real_mount(mnt))) {
                dentry = mnt->mnt_mountpoint;
                mnt = mnt->mnt_parent;
        }
@@ -2652,11 +2652,11 @@ SYSCALL_DEFINE2(pivot_root, const char __user *, new_root,
        error = -EINVAL;
        if (root.mnt->mnt_root != root.dentry)
                goto out4; /* not a mountpoint */
-       if (!mnt_has_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 (!mnt_has_parent(new.mnt))
+       if (!mnt_has_parent(new_mnt))
                goto out4; /* not attached */
        /* make sure we can reach put_old from new_root */
        if (!is_path_reachable(old.mnt, old.dentry, &new))