vfs: spread struct mount - mnt_has_parent

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

3 files changed, 13 insertions, 12 deletions

diff --git a/fs/dcache.c b/fs/dcache.c
index 64c8ce4c147f..1834e715f814 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -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;
diff --git a/fs/mount.h b/fs/mount.h
index 831e7c86835b..541daf568f63 100644
--- a/fs/mount.h
+++ b/fs/mount.h
@@ -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);
diff --git a/fs/namespace.c b/fs/namespace.c
index 17927f9eeca4..ced3aa53fb38 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -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))