Implement kernel brk

src/kernel/memory/kbrk.c

@@ -0,0 +1,18 @@
+#include <memory.h>
+#include <debug.h>
+
+static long _brk = KERNEL_BRK0;
+
+long kbrk(long brk, long, long, long, long, long)
+{
+    if(brk)
+    {
+        while(_brk < brk) {
+            vmm_set_page(kernel_P4, _brk, pmm_alloc(), PAGE_WRITE | PAGE_PRESENT);
+            _brk += PAGE_SIZE;
+        }
+        return _brk;
+    } else {
+        return _brk;
+    }
+}