paging constants into header

1 files changed, 15 insertions, 0 deletions

diff --git a/api/kernel/memory/paging.h b/api/kernel/memory/paging.h
new file mode 100644
index 0000000..25e5eea
--- /dev/null
+++ b/api/kernel/memory/paging.h
@@ -0,0 +1,15 @@
+#pragma once
+
+#define PAGE_PR 1
+#define PAGE_WR 2
+
+#define PAGE_MAP_LEVELS 4
+#define PAGE_MAP_BITS 9
+#define PAGE_OFFSET_BITS 12
+
+#define PAGE_TABLE_INDEX_MASK ((1 << PAGE_MAP_BITS) - 1)
+#define PAGE_TABLE_ADDRESS_MASK ~((1 << PAGE_OFFSET_BITS) - 1)
+
+#define page_table_index_bits(l) (PAGE_OFFSET_BITS + PAGE_MAP_BITS * (l - 1))
+#define page_table_index(v, l) ((v >> page_table_index_bits(l)) & PAGE_TABLE_INDEX_MASK)
+