eCryptfs: do not try to open device files on mknod

When creating device nodes, eCryptfs needs to delay actually opening the lower
persistent file until an application tries to open.  Device handles may not be
backed by anything when they first come into existence.

[Valdis.Kletnieks@vt.edu: build fix]
Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: <Valdis.Kletnieks@vt.edu}
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index 7315547..2609087 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -308,7 +308,8 @@
 		d_add(dentry, NULL);
 		goto out;
 	}
-	rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 1);
+	rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb,
+				ECRYPTFS_INTERPOSE_FLAG_D_ADD);
 	if (rc) {
 		ecryptfs_printk(KERN_ERR, "Error interposing\n");
 		goto out_dput;
@@ -537,7 +538,8 @@
 	rc = vfs_mknod(lower_dir_dentry->d_inode, lower_dentry, mode, dev);
 	if (rc || !lower_dentry->d_inode)
 		goto out;
-	rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb, 0);
+	rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb,
+				ECRYPTFS_INTERPOSE_FLAG_DELAY_PERSISTENT_FILE);
 	if (rc)
 		goto out;
 	fsstack_copy_attr_times(dir, lower_dir_dentry->d_inode);