From 96a877c95b5d37ed2fea605c675ab4a4f4d2a2ae Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Thomas=20Lov=C3=A9n?= <thomasloven@gmail.com>
Date: Wed, 3 Jan 2018 14:05:27 +0100
Subject: [PATCH] VMM - touch_page stops at P2 for huge pages

---
 src/kernel/memory/vmm.c  | 5 +++++
 src/kernel/memory/vmm.tt | 9 +++++++--
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/src/kernel/memory/vmm.c b/src/kernel/memory/vmm.c
index 595e443..6acfd13 100644
--- a/src/kernel/memory/vmm.c
+++ b/src/kernel/memory/vmm.c
@@ -73,6 +73,9 @@ int touch_page(void *P4, uintptr_t addr, uint16_t flags)
 {
   if(!P4) return -1;
 
+  int huge=(flags & PAGE_HUGE)?1:0;
+  flags ^= PAGE_HUGE*huge;
+
   if((!P4e(P4, addr).present)
       && (!(P4e(P4, addr).value = pmm_alloc())))
     return -1;
@@ -83,6 +86,8 @@ int touch_page(void *P4, uintptr_t addr, uint16_t flags)
     return -1;
   P3e(P4, addr).value |= flags | PAGE_PRESENT;
 
+  if(huge) return 0;
+
   if((!P2e(P4, addr).present)
       && (!(P2e(P4, addr).value = pmm_alloc())))
     return -1;
diff --git a/src/kernel/memory/vmm.tt b/src/kernel/memory/vmm.tt
index 161b0a6..b3e729b 100644
--- a/src/kernel/memory/vmm.tt
+++ b/src/kernel/memory/vmm.tt
@@ -143,9 +143,9 @@ TEST(touch_page_adds_P1)
 }
 TEST(touch_page_sets_flags)
 {
-  touch_page(p4, 0, 0x123);
+  touch_page(p4, 0, PAGE_WRITE);
 
-  ASSERT_EQ_PTR(p2[0], (uintptr_t)p1 | 0x123 | PAGE_PRESENT);
+  ASSERT_EQ_PTR(p2[0], (uintptr_t)p1 | PAGE_WRITE | PAGE_PRESENT);
 }
 TEST(touch_page_fails_if_out_of_pages)
 {
@@ -153,6 +153,11 @@ TEST(touch_page_fails_if_out_of_pages)
   int retval = touch_page(p4, 0, 0);
   ASSERT_NEQ_INT(retval, 0);
 }
+TEST(touch_page_stops_at_P2_for_huge_pages)
+{
+  touch_page(p4, 0, PAGE_HUGE);
+  ASSERT_EQ_PTR(p2[0], 0);
+}
 
 TEST(free_page_unsets_page)
 {