From 47dbdd7412091536ed71180982a774d4eb4b3b0d Mon Sep 17 00:00:00 2001
From: mark <markm@cs.wisc.edu>
Date: Fri, 15 May 2020 18:19:42 -0500
Subject: [PATCH] add recursive_idx for boot info

---
 src/bootinfo/mod.rs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/bootinfo/mod.rs b/src/bootinfo/mod.rs
index 16f6c4c1..b1c2b171 100644
--- a/src/bootinfo/mod.rs
+++ b/src/bootinfo/mod.rs
@@ -85,6 +85,12 @@ impl BootInfo {
             None
         }
     }
+
+    /// Returns the index into the page tables that recursively maps the page tables themselves.
+    #[cfg(feature = "recursive_page_table")]
+    pub fn recursive_index(&self) -> u16 {
+        ((self.recursive_page_table_addr >> 12) & 0x1FF) as u16
+    }
 }
 
 /// Information about the thread local storage (TLS) template.