1 files changed, 35 insertions, 0 deletions
diff --git a/machine/vm.h b/machine/vm.h
new file mode 100644
index 0000000..f51c639
--- /dev/null
+++ b/machine/vm.h
@@ -0,0 +1,35 @@
+#ifndef _VM_H
+#define _VM_H
+
+#include "encoding.h"
+#include <stdint.h>
+
+#define MEGAPAGE_SIZE ((uintptr_t)(RISCV_PGSIZE << RISCV_PGLEVEL_BITS))
+#ifdef __riscv64
+# define VM_CHOICE VM_SV39
+# define VA_BITS 39
+# define GIGAPAGE_SIZE (MEGAPAGE_SIZE << RISCV_PGLEVEL_BITS)
+#else
+# define VM_CHOICE VM_SV32
+# define VA_BITS 32
+#endif
+
+typedef uintptr_t pte_t;
+extern pte_t* root_page_table;
+
+static inline void flush_tlb()
+{
+  asm volatile("sfence.vm");
+}
+
+static inline pte_t pte_create(uintptr_t ppn, int type)
+{
+  return (ppn << PTE_PPN_SHIFT) | PTE_V | type;
+}
+
+static inline pte_t ptd_create(uintptr_t ppn)
+{
+  return pte_create(ppn, PTE_TYPE_TABLE);
+}
+
+#endif