vfs: spread struct mount - clone_mnt/copy_tree argument

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

1 files changed, 33 insertions, 30 deletions

diff --git a/fs/namespace.c b/fs/namespace.c
index fa0f30d862c6..211455e2cd17 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -687,17 +687,17 @@ vfs_kern_mount(struct file_system_type *type, int flags, const char *name, void
 }
 EXPORT_SYMBOL_GPL(vfs_kern_mount);
 
-static struct mount *clone_mnt(struct vfsmount *old, struct dentry *root,
+static struct mount *clone_mnt(struct mount *old, struct dentry *root,
                                         int flag)
 {
-        struct super_block *sb = old->mnt_sb;
-        struct mount *mnt = alloc_vfsmnt(old->mnt_devname);
+        struct super_block *sb = old->mnt.mnt_sb;
+        struct mount *mnt = alloc_vfsmnt(old->mnt.mnt_devname);
 
         if (mnt) {
                 if (flag & (CL_SLAVE | CL_PRIVATE))
                         mnt->mnt.mnt_group_id = 0; /* not a peer of original */
                 else
-                        mnt->mnt.mnt_group_id = old->mnt_group_id;
+                        mnt->mnt.mnt_group_id = old->mnt.mnt_group_id;
 
                 if ((flag & CL_MAKE_SHARED) && !mnt->mnt.mnt_group_id) {
                         int err = mnt_alloc_group_id(mnt);
@@ -705,7 +705,7 @@ static struct mount *clone_mnt(struct vfsmount *old, struct dentry *root,
                                 goto out_free;
                 }
 
-                mnt->mnt.mnt_flags = old->mnt_flags & ~MNT_WRITE_HOLD;
+                mnt->mnt.mnt_flags = old->mnt.mnt_flags & ~MNT_WRITE_HOLD;
                 atomic_inc(&sb->s_active);
                 mnt->mnt.mnt_sb = sb;
                 mnt->mnt.mnt_root = dget(root);
@@ -713,15 +713,15 @@ static struct mount *clone_mnt(struct vfsmount *old, struct dentry *root,
                 mnt->mnt.mnt_parent = &mnt->mnt;
 
                 if (flag & CL_SLAVE) {
-                        list_add(&mnt->mnt.mnt_slave, &old->mnt_slave_list);
-                        mnt->mnt.mnt_master = old;
+                        list_add(&mnt->mnt.mnt_slave, &old->mnt.mnt_slave_list);
+                        mnt->mnt.mnt_master = &old->mnt;
                         CLEAR_MNT_SHARED(&mnt->mnt);
                 } else if (!(flag & CL_PRIVATE)) {
-                        if ((flag & CL_MAKE_SHARED) || IS_MNT_SHARED(old))
-                                list_add(&mnt->mnt.mnt_share, &old->mnt_share);
-                        if (IS_MNT_SLAVE(old))
-                                list_add(&mnt->mnt.mnt_slave, &old->mnt_slave);
-                        mnt->mnt.mnt_master = old->mnt_master;
+                        if ((flag & CL_MAKE_SHARED) || IS_MNT_SHARED(&old->mnt))
+                                list_add(&mnt->mnt.mnt_share, &old->mnt.mnt_share);
+                        if (IS_MNT_SLAVE(&old->mnt))
+                                list_add(&mnt->mnt.mnt_slave, &old->mnt.mnt_slave);
+                        mnt->mnt.mnt_master = old->mnt.mnt_master;
                 }
                 if (flag & CL_MAKE_SHARED)
                         set_mnt_shared(mnt);
@@ -729,8 +729,8 @@ static struct mount *clone_mnt(struct vfsmount *old, struct dentry *root,
                 /* stick the duplicate mount on the same expiry list
                  * as the original if that was on one */
                 if (flag & CL_EXPIRE) {
-                        if (!list_empty(&old->mnt_expire))
-                                list_add(&mnt->mnt.mnt_expire, &old->mnt_expire);
+                        if (!list_empty(&old->mnt.mnt_expire))
+                                list_add(&mnt->mnt.mnt_expire, &old->mnt.mnt_expire);
                 }
         }
         return mnt;
@@ -1408,23 +1408,23 @@ static int mount_is_safe(struct path *path)
 #endif
 }
 
-struct mount *copy_tree(struct vfsmount *mnt, struct dentry *dentry,
+struct mount *copy_tree(struct mount *mnt, struct dentry *dentry,
                                         int flag)
 {
-        struct mount *res, *q;
-        struct vfsmount *p, *r;
+        struct mount *res, *p, *q;
+        struct vfsmount *r;
         struct path path;
 
-        if (!(flag & CL_COPY_ALL) && IS_MNT_UNBINDABLE(mnt))
+        if (!(flag & CL_COPY_ALL) && IS_MNT_UNBINDABLE(&mnt->mnt))
                 return NULL;
 
         res = q = clone_mnt(mnt, dentry, flag);
         if (!q)
                 goto Enomem;
-        q->mnt.mnt_mountpoint = mnt->mnt_mountpoint;
+        q->mnt.mnt_mountpoint = mnt->mnt.mnt_mountpoint;
 
         p = mnt;
-        list_for_each_entry(r, &mnt->mnt_mounts, mnt_child) {
+        list_for_each_entry(r, &mnt->mnt.mnt_mounts, mnt_child) {
                 struct mount *s;
                 if (!is_subdir(r->mnt_mountpoint, dentry))
                         continue;
@@ -1434,14 +1434,14 @@ struct mount *copy_tree(struct vfsmount *mnt, struct dentry *dentry,
                                 s = skip_mnt_tree(s);
                                 continue;
                         }
-                        while (p != s->mnt.mnt_parent) {
-                                p = p->mnt_parent;
+                        while (p != real_mount(s->mnt.mnt_parent)) {
+                                p = real_mount(p->mnt.mnt_parent);
                                 q = real_mount(q->mnt.mnt_parent);
                         }
-                        p = &s->mnt;
+                        p = s;
                         path.mnt = &q->mnt;
-                        path.dentry = p->mnt_mountpoint;
-                        q = clone_mnt(p, p->mnt_root, flag);
+                        path.dentry = p->mnt.mnt_mountpoint;
+                        q = clone_mnt(p, p->mnt.mnt_root, flag);
                         if (!q)
                                 goto Enomem;
                         br_write_lock(vfsmount_lock);
@@ -1466,7 +1466,8 @@ struct vfsmount *collect_mounts(struct path *path)
 {
         struct mount *tree;
         down_write(&namespace_sem);
-        tree = copy_tree(path->mnt, path->dentry, CL_COPY_ALL | CL_PRIVATE);
+        tree = copy_tree(real_mount(path->mnt), path->dentry,
+                         CL_COPY_ALL | CL_PRIVATE);
         up_write(&namespace_sem);
         return tree ? &tree->mnt : NULL;
 }
@@ -1740,7 +1741,7 @@ static int do_loopback(struct path *path, char *old_name,
 {
         LIST_HEAD(umount_list);
         struct path old_path;
-        struct mount *mnt = NULL;
+        struct mount *mnt = NULL, *old;
         int err = mount_is_safe(path);
         if (err)
                 return err;
@@ -1754,6 +1755,8 @@ static int do_loopback(struct path *path, char *old_name,
         if (err)
                 goto out;
 
+        old = real_mount(old_path.mnt);
+
         err = -EINVAL;
         if (IS_MNT_UNBINDABLE(old_path.mnt))
                 goto out2;
@@ -1763,9 +1766,9 @@ static int do_loopback(struct path *path, char *old_name,
 
         err = -ENOMEM;
         if (recurse)
-                mnt = copy_tree(old_path.mnt, old_path.dentry, 0);
+                mnt = copy_tree(old, old_path.dentry, 0);
         else
-                mnt = clone_mnt(old_path.mnt, old_path.dentry, 0);
+                mnt = clone_mnt(old, old_path.dentry, 0);
 
         if (!mnt)
                 goto out2;
@@ -2394,7 +2397,7 @@ static struct mnt_namespace *dup_mnt_ns(struct mnt_namespace *mnt_ns,
 
         down_write(&namespace_sem);
         /* First pass: copy the tree topology */
-        new = copy_tree(mnt_ns->root, mnt_ns->root->mnt_root,
+        new = copy_tree(real_mount(mnt_ns->root), mnt_ns->root->mnt_root,
                                         CL_COPY_ALL | CL_EXPIRE);
         if (!new) {
                 up_write(&namespace_sem);