1 files changed, 31 insertions, 0 deletions
diff --git a/src/kernel/include/paging.h b/src/kernel/include/paging.h
new file mode 100644
index 0000000..44014a2
--- /dev/null
+++ b/src/kernel/include/paging.h
@@ -0,0 +1,31 @@
+#pragma once
+
+#include <sys.h>
+#include <stdbool.h>
+
+struct page_directory;
+typedef struct page_directory pagedir_t;
+
+
+void paging_setup(void* kernel_data_end);
+
+pagedir_t *get_current_pagedir();
+pagedir_t *get_kernel_pagedir();
+
+void switch_pagedir(pagedir_t *pd);
+
+// these functions are always relative to the currently mapped page directory
+uint32_t pd_get_frame(void* vaddr);		// get physical frame for virtual address
+int pd_map_page(void* vaddr, uint32_t frame_id, bool rw);		// returns nonzero on error
+void pd_unmap_page(void* vaddr);	// does nothing if page not mapped
+
+// Note on concurrency : we expect that multiple threads will not try to map/unmap
+// pages in the same region at the same time. It can nevertheless happen that
+// several threads try to map pages that belong to the same 4M-section, and in that
+// case both might require the allocation of a new PT at the same location. These
+// cases are well-handled (the pagedir_t type contains a mutex used for this)
+
+pagedir_t *create_pagedir();		// returns zero on error
+void delete_pagedir(pagedir_t *pd);
+
+/* vim: set ts=4 sw=4 tw=0 noet :*/