From 95e2f274e3720391cad13db477d5ad4cec4c8fe3 Mon Sep 17 00:00:00 2001
From: "E. Almqvist" <elalmqvist@gmail.com>
Date: Fri, 3 Dec 2021 09:44:52 +0100
Subject: [PATCH] Bitmap thing

---
 Makefile             |  2 +-
 kernel/memory.c      | 14 ++++++++++++--
 kernel/memory.h      |  9 +++++++--
 kernel/sr_memory.asm |  0
 lib/types.h          |  1 +
 5 files changed, 21 insertions(+), 5 deletions(-)
 create mode 100644 kernel/sr_memory.asm
 create mode 100644 lib/types.h

diff --git a/Makefile b/Makefile
index f5935b7..bece67e 100644
--- a/Makefile
+++ b/Makefile
@@ -22,7 +22,7 @@ eos_grub.iso : kernel.bin grub/grub.cfg
 eos.iso: bootloader/bootloader.bin kernel.bin
 	cat $^ > eos.iso
 
-kernel.bin: kernel/kernel_entry.o kernel/enable_paging.o $(OBJ) 
+kernel.bin: kernel/kernel_entry.o kernel/sr_memory.o kernel/enable_paging.o $(OBJ) 
 	gcc -o $@ $^ -Wl,--oformat=binary -ffreestanding -nostdlib -shared -Ttext 0x1000 -m32
 
 
diff --git a/kernel/memory.c b/kernel/memory.c
index bb577e4..236e93e 100644
--- a/kernel/memory.c
+++ b/kernel/memory.c
@@ -7,8 +7,18 @@
 // i.e. : bit i of byte n define status of block 8n+i
 // block = 8n+i
 
-int* alloc_cursor; // keep track of last location that was allocated (may improve speed)
+// in 32-bit mode, we have access to 2^32 blocks
+// which is (2^32)*BLOCK_SIZE blocks
+// and with a blocksize of 1024, we git around 4.3 trillion blocks
+// which is more than enough
 
-void init_pmm(unsigned int map_addr, unsigned int bsize) {
+int bitmap = 0;
 
+enum bitmap_flag {
+	FREE,
+	ALLOC
+};
+
+void mod_bitmap(uint block, uint bit, uint bflag) {
+	
 }
diff --git a/kernel/memory.h b/kernel/memory.h
index 5d46f0b..93cfa77 100644
--- a/kernel/memory.h
+++ b/kernel/memory.h
@@ -1,5 +1,10 @@
-#define BLOCK_SIZE 4 // 32 bits = 4 bytes
+#include "../lib/types.h"
+
+#define BLOCK_SIZE 1024 // 1 KiB
 #define MEMSIZE_TO_BLOCKS(n) ((n*1024)/BLOCK_SIZE)
 
-void init_pmm(unsigned int map_addr, unsigned int bsize); // Initialize physical memory manager
+enum bitmap_flag;
+
+// void init_pmm(uint map_addr, uint bsize); // Initialize physical memory manager
 
+void mod_bitmap(uint block, uint bit, uint flag);
diff --git a/kernel/sr_memory.asm b/kernel/sr_memory.asm
new file mode 100644
index 0000000..e69de29
diff --git a/lib/types.h b/lib/types.h
new file mode 100644
index 0000000..9113551
--- /dev/null
+++ b/lib/types.h
@@ -0,0 +1 @@
+typedef unsigned int uint;