1 files changed, 29 insertions, 9 deletions

diff --git a/drivers/base/devtmpfs.c b/drivers/base/devtmpfs.c
index ba5c80903efe..30d0523014e0 100644
--- a/drivers/base/devtmpfs.c
+++ b/drivers/base/devtmpfs.c
@@ -56,20 +56,32 @@ static int __init mount_param(char *str)
 }
 __setup("devtmpfs.mount=", mount_param);
 
-static struct dentry *dev_mount(struct file_system_type *fs_type, int flags,
+static struct vfsmount *mnt;
+
+static struct dentry *public_dev_mount(struct file_system_type *fs_type, int flags,
                       const char *dev_name, void *data)
 {
+        struct super_block *s = mnt->mnt_sb;
+        atomic_inc(&s->s_active);
+        down_write(&s->s_umount);
+        return dget(s->s_root);
+}
+
+static struct file_system_type internal_fs_type = {
+        .name = "devtmpfs",
 #ifdef CONFIG_TMPFS
-        return mount_single(fs_type, flags, data, shmem_fill_super);
+        .init_fs_context = shmem_init_fs_context,
+        .parameters     = &shmem_fs_parameters,
 #else
-        return mount_single(fs_type, flags, data, ramfs_fill_super);
+        .init_fs_context = ramfs_init_fs_context,
+        .parameters     = &ramfs_fs_parameters,
 #endif
-}
+        .kill_sb = kill_litter_super,
+};
 
 static struct file_system_type dev_fs_type = {
         .name = "devtmpfs",
-        .mount = dev_mount,
-        .kill_sb = kill_litter_super,
+        .mount = public_dev_mount,
 };
 
 #ifdef CONFIG_BLOCK
@@ -378,12 +390,11 @@ static int handle(const char *name, umode_t mode, kuid_t uid, kgid_t gid,
 
 static int devtmpfsd(void *p)
 {
-        char options[] = "mode=0755";
         int *err = p;
         *err = ksys_unshare(CLONE_NEWNS);
         if (*err)
                 goto out;
-        *err = ksys_mount("devtmpfs", "/", "devtmpfs", MS_SILENT, options);
+        *err = ksys_mount("devtmpfs", "/", "devtmpfs", MS_SILENT, NULL);
         if (*err)
                 goto out;
         ksys_chdir("/.."); /* will traverse into overmounted root */
@@ -420,7 +431,16 @@ out:
  */
 int __init devtmpfs_init(void)
 {
-        int err = register_filesystem(&dev_fs_type);
+        char opts[] = "mode=0755";
+        int err;
+
+        mnt = vfs_kern_mount(&internal_fs_type, 0, "devtmpfs", opts);
+        if (IS_ERR(mnt)) {
+                printk(KERN_ERR "devtmpfs: unable to create devtmpfs %ld\n",
+                                PTR_ERR(mnt));
+                return PTR_ERR(mnt);
+        }
+        err = register_filesystem(&dev_fs_type);
         if (err) {
                 printk(KERN_ERR "devtmpfs: unable to register devtmpfs "
                        "type %i\n", err);