1 files changed, 94 insertions, 0 deletions
diff --git a/src/stem/mem.c b/src/stem/mem.c
new file mode 100644
index 0000000..babe079
--- /dev/null
+++ b/src/stem/mem.c
@@ -0,0 +1,94 @@
+#include "mem.h"
+#include "sys.h"
+#include "paging.h"
+#include "heap.h"
+#include "monitor.h"
+
+#define FREEPAGESTOKEEP 5
+
+#define KHEAP_IDXSIZE 0x1000
+#define KHEAP_INITSIZE 0x8000
+#define KHEAP_MAXSIZE 0x08000000
+
+size_t mem_placementAddr;
+static uint32_t kheap_working = 0;
+
+
+// ******************************
+// 									PAGE ALLOCATION
+// 															****************************
+static struct freepage {
+   size_t virt, phys;
+} freepages[FREEPAGESTOKEEP];
+uint32_t freepagecount = 0;
+
+static void get_free_pages() {
+	static uint32_t locked = 0;
+	uint32_t i;
+	if (locked) return;
+	locked = 1;
+	while (freepagecount < FREEPAGESTOKEEP) {
+		if (kheap_working) {
+			for (i = 0xFFFFF000; i >= 0xF0000000; i -= 0x1000) {
+				if (pagedir_getPage(kernel_pagedir, i, 1)->frame == 0) break;
+			}
+			freepages[freepagecount].virt = i;
+			freepages[freepagecount].phys = frame_alloc() * 0x1000;
+			page_map(pagedir_getPage(kernel_pagedir, i, 0), i, 0, 0);
+		} else {
+			if (mem_placementAddr & 0xFFFFF000) {
+				mem_placementAddr &= 0xFFFFF000;
+				mem_placementAddr += 0x1000;
+			}
+			freepages[freepagecount].virt = (size_t)kmalloc(0x1000);
+			freepages[freepagecount].phys = freepages[freepagecount].virt - 0xE0000000;
+			freepagecount++;
+		}
+	}
+	locked = 0;
+}
+
+void* kmalloc_page(size_t *phys) {
+	cli();
+	get_free_pages();
+	freepagecount--;
+	*phys = freepages[freepagecount].phys;
+	size_t tmp = freepages[freepagecount].virt;
+	sti();
+	return (void*)tmp;
+}
+
+void kfree_page(void* ptr) {
+	size_t addr = (size_t)ptr;
+	if (kheap_working) {		//With this we can know if paging works
+		page_unmapFree(pagedir_getPage(kernel_pagedir, addr, 0));
+	}
+}
+
+//***********************************
+//										NORMAL MEMORY ALLOCATION
+//																	*************************
+
+static struct heap kheap;
+
+void kheap_init() {
+	heap_create(&kheap, (mem_placementAddr & 0xFFFFF000) + 0x1000, KHEAP_IDXSIZE, KHEAP_INITSIZE, KHEAP_MAXSIZE);
+	kheap_working = 1;
+	monitor_write("Kernel heap ok\n");
+}
+
+void* kmalloc(size_t size) {
+	if (kheap_working) {
+		return heap_alloc(&kheap, size);
+	} else {
+		size_t tmp = mem_placementAddr;
+		mem_placementAddr += size;
+		return (void*)tmp;
+	}
+}
+
+void kfree(void* ptr) {
+	if (kheap_working) {
+		heap_free(&kheap, ptr);
+	}
+}