Implement APIC, RTC, basic ACPI parser and timer support

[lunaix-os.git] / lunaix-os / kernel / mm / vmm.c

diff --git a/lunaix-os/kernel/mm/vmm.c b/lunaix-os/kernel/mm/vmm.c
index 54da656e695519ac61734665226df0be721be80e..928c289f86f4fc6c03017ab104574a7990ecc8e5 100644 (file)
--- a/lunaix-os/kernel/mm/vmm.c
+++ b/lunaix-os/kernel/mm/vmm.c
@@ -1,5 +1,5 @@
 #include <hal/cpu.h>
-#include <libc/string.h>
+#include <klibc/string.h>
 #include <lunaix/mm/page.h>
 #include <lunaix/mm/pmm.h>
 #include <lunaix/mm/vmm.h>
@@ -52,8 +52,14 @@ __vmm_map_internal(uint32_t l1_inx,
         memset((void*)L2_VADDR(l1_inx), 0, PG_SIZE);
     }
 
-    if (!forced && l2pt->entry[l2_inx]) {
-        return 0;
+    x86_pte_t l2pte = l2pt->entry[l2_inx];
+    if (l2pte) {
+        if (!forced) {
+            return 0;
+        }
+        if (HAS_FLAGS(l2pte, PG_PRESENT)) {
+            assert_msg(pmm_free_page(GET_PG_ADDR(l2pte)), "fail to release physical page");
+        }
     }
 
     l2pt->entry[l2_inx] = NEW_L2_ENTRY(attr, pa);
@@ -162,6 +168,21 @@ vmm_alloc_pages(void* va, size_t sz, pt_attr tattr)
     return true;
 }
 
+void
+vmm_set_mapping(void* va, void* pa, pt_attr attr) {
+    assert(((uintptr_t)va & 0xFFFU) == 0);
+
+    uint32_t l1_index = L1_INDEX(va);
+    uint32_t l2_index = L2_INDEX(va);
+
+    // prevent map of recursive mapping region
+    if (l1_index == 1023) {
+        return;
+    }
+    
+    __vmm_map_internal(l1_index, l2_index, (uintptr_t)pa, attr, false);
+}
+
 void
 vmm_unmap_page(void* va)
 {
@@ -169,6 +190,12 @@ vmm_unmap_page(void* va)
 
     uint32_t l1_index = L1_INDEX(va);
     uint32_t l2_index = L2_INDEX(va);
+
+    // prevent unmap of recursive mapping region
+    if (l1_index == 1023) {
+        return;
+    }
+
     x86_page_table* l1pt = (x86_page_table*)L1_BASE_VADDR;
 
     x86_pte_t l1pte = l1pt->entry[l1_index];