From 563758b1bd168a988855089df37821e1e8b5f17e Mon Sep 17 00:00:00 2001
From: josh <josh@5b3e749e-e535-0410-8002-a9bb6afbdfca>
Date: Mon, 1 Feb 2010 04:21:29 +0000
Subject: [PATCH] added PAGE_DIR_SELF_REF2 to fix bug in page directory
 self-referencing

git-svn-id: svn://anubis/hos/trunk@100 5b3e749e-e535-0410-8002-a9bb6afbdfca
---
 kernel/include/hos_defines.h | 2 +-
 kernel/mm/mm.cc              | 8 ++++----
 kernel/mm/mm.h               | 3 ++-
 3 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/kernel/include/hos_defines.h b/kernel/include/hos_defines.h
index 8228852..e9a7c41 100644
--- a/kernel/include/hos_defines.h
+++ b/kernel/include/hos_defines.h
@@ -6,7 +6,7 @@
 
 #define KERNEL_OFFSET           0x00000000
 
-#define PAGE_LOG_SIZE           12
+#define PAGE_LOG_SIZE           12u
 #define PAGE_SIZE               (1 << PAGE_LOG_SIZE)
 #define PAGE_HIGH_MASK          (0xFFFFFFFFu << PAGE_LOG_SIZE)
 #define PAGE_LOW_MASK           (0xFFFFFFFFu >> (32 - PAGE_LOG_SIZE))
diff --git a/kernel/mm/mm.cc b/kernel/mm/mm.cc
index 3827379..20b0ac3 100644
--- a/kernel/mm/mm.cc
+++ b/kernel/mm/mm.cc
@@ -147,7 +147,7 @@ void mm_bootstrap()
     /* ok, now mm_early_map() should be functional */
 
     /* map in the page directory itself so we can modify it once paging is on */
-    mm_early_map(PAGE_DIR_SELF_REF, page_directory_phys, 0, 1);
+    mm_early_map(PAGE_DIR_SELF_REF2, page_directory_phys, 0, 1);
 
     /* map in the physical page allocator pages */
     for (int i = 0; i <= last_page_alloc_page; i++)
@@ -262,7 +262,8 @@ int mm_early_map(u32_t virtual_address, u32_t physical_address,
     u32_t page_table_phys =
         (*early_page_directory_ptr)[directory_index] & PAGE_HIGH_MASK;
 
-    u32_t * page_table = (u32_t *) (page_table_phys + KERNEL_OFFSET);
+    pagedirectory_entry_t * page_table =
+        (pagedirectory_entry_t *) (page_table_phys + KERNEL_OFFSET);
 
     page_table[table_index] = (physical_address & PAGE_HIGH_MASK)
                             | (user_mode & 0x1) << 2
@@ -282,8 +283,7 @@ int mm_map(u32_t virtual_address, u32_t physical_address,
     u32_t directory_index = (virtual_address >> 22) & 0x3FF;
     u32_t table_index = (virtual_address >> 12) & 0x3FF;
     pagedirectory_entry_t * page_dir_entry = (pagedirectory_entry_t *)
-        (PAGE_DIR_SELF_REF | (PAGE_DIR_SELF_REF_INDEX << 12)
-         | (directory_index << 2));
+        (PAGE_DIR_SELF_REF2 | (directory_index << 2));
 
     if (*page_dir_entry == 0)
     {
diff --git a/kernel/mm/mm.h b/kernel/mm/mm.h
index fea5997..74b24ce 100644
--- a/kernel/mm/mm.h
+++ b/kernel/mm/mm.h
@@ -13,8 +13,9 @@ typedef u32_t pagedirectory_entry_t;
 
 #define NUM_PAGETABLE_ENTRIES   (PAGE_SIZE / sizeof(pagedirectory_entry_t))
 
-#define PAGE_DIR_SELF_REF   (0x20000000 - (PAGE_SIZE * NUM_PAGETABLE_ENTRIES))
+#define PAGE_DIR_SELF_REF   (0x20000000u - (PAGE_SIZE * NUM_PAGETABLE_ENTRIES))
 #define PAGE_DIR_SELF_REF_INDEX ((PAGE_DIR_SELF_REF >> 22) & 0x3FF)
+#define PAGE_DIR_SELF_REF2  (PAGE_DIR_SELF_REF | (PAGE_DIR_SELF_REF_INDEX << 12))
 
 typedef pagedirectory_entry_t pagedirectory_t[NUM_PAGETABLE_ENTRIES];