Add function to map a region of virtual memory to real mem

src/mem.c

@@ -132,6 +132,13 @@ page_directory_entry* initiate_directory()
     return page_directory;
     return page_directory;
 }
 }
 
 
+// Expect addr to be page aligned
+void map_directory_entry(void* addr, page_directory_entry* page_dir) {
+    page_table_entry* new_page_table = (page_table_entry*) (malloc(2048)+1024)&0xfffffc00;
+    populate_page_table(new_page_table, addr & 0xffc00000, 1024, 0);
+    page_dir[addr >> 22] = new_page_table;
+}
+
 void* malloc(uint32_t bytes)
 void* malloc(uint32_t bytes)
 {
 {
     void* old_mark = memory_mark;
     void* old_mark = memory_mark;

src/mem.h

@@ -31,6 +31,9 @@ extern void enablePaging();
 page_directory_entry* initiate_directory();
 page_directory_entry* initiate_directory();
 page_directory_entry* mem_init_kern_tables(multiboot_memory_map* mmap, multiboot_memory_map* mmap_end);
 page_directory_entry* mem_init_kern_tables(multiboot_memory_map* mmap, multiboot_memory_map* mmap_end);
 
 
+// map_directory_entry maps the real address given to a page directory at the same memory
+void map_directory_entry(void*);
+
 // memory mark stores a counter of bytes for the most recently used
 // memory mark stores a counter of bytes for the most recently used
 // memory. Everything before it is used and all valid memory after it
 // memory. Everything before it is used and all valid memory after it
 // is free
 // is free