more fixes

arch/x86_64/pmap.c

@@ -6,6 +6,10 @@ void pte_clear(pte_t* pte) {
     *pte = 0;
 }
 
+void pte_flush(uintptr_t vaddr) {
+    asm volatile("invlpg [%0]" ::"r"(vaddr) : "memory");
+}
+
 pte_t pte_build(phys_t addr, enum pte_flags flags, enum cache_mode cache) {
     pte_t result = ((pte_t)addr & ARCH_PTE_ADDR_MASK) | ARCH_FLAG_PRESENT;
 
@@ -19,6 +23,21 @@ pte_t pte_build(phys_t addr, enum pte_flags flags, enum cache_mode cache) {
             result |= ARCH_FLAG_READ_WRITE;
         if (!(flags & PTE_EXEC))
             result |= ARCH_FLAG_EXECUTE_DISABLE;
+
+        switch (cache) {
+        case CACHE_ANY:
+        case CACHE_WRITE_BACK:
+            break;
+        case CACHE_WRITE_THROUGH:
+            result |= ARCH_FLAG_WRITE_THROUGH;
+            break;
+        case CACHE_MMIO:
+            result |= ARCH_FLAG_CACHE_DISABLE | ARCH_FLAG_WRITE_THROUGH;
+            break;
+        case CACHE_WRITE_COMBINE:
+            result |= ARCH_FLAG_ATTRIBUTE_TABLE | ARCH_FLAG_WRITE_THROUGH;
+            break;
+        }
     }
     return result;
 }