From 1e6f9083b872e7d83e21168419472e1a12f6f052 Mon Sep 17 00:00:00 2001
From: g1n <g1n@ttm.sh>
Date: Sat, 12 Feb 2022 18:13:39 +0200
Subject: [PATCH] Add kfree_frame for page frame allocator

---
 src/include/paging.h | 1 +
 src/paging.c         | 5 +++++
 2 files changed, 6 insertions(+)

diff --git a/src/include/paging.h b/src/include/paging.h
index 5208218..d4a46af 100644
--- a/src/include/paging.h
+++ b/src/include/paging.h
@@ -10,6 +10,7 @@
 typedef uint32_t page_addr_t;
 
 page_addr_t kalloc_frame();
+void kfree_frame(page_addr_t addr);
 void paging_init();
 void page_fault(registers_t regs);
 
diff --git a/src/paging.c b/src/paging.c
index b148241..916c43e 100644
--- a/src/paging.c
+++ b/src/paging.c
@@ -61,6 +61,11 @@ page_addr_t kalloc_frame() {
   return page_frame_number * PAGE_SIZE;
 }
 
+void kfree_frame(page_addr_t addr) {
+  page_addr_t index = addr / PAGE_SIZE;
+  bitmap[index / ENTRY_WIDTH] |= (1U << ((index / ENTRY_WIDTH) + (index % ENTRY_WIDTH)));
+}
+
 void paging_init() {
   unsigned int i;
   for(i = 0; i < 1024; i++) {