Implement paging

1 files changed, 45 insertions, 0 deletions

diff --git a/kernel/heap.c b/kernel/heap.c
new file mode 100644
index 0000000..d1f1021
--- /dev/null
+++ b/kernel/heap.c
@@ -0,0 +1,45 @@
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include "paging.h"
+
+/* a simple pointer-arithmetic-based malloc */
+
+/* a symbol put there by the linker */
+extern uint32_t link_mem_end;
+uint32_t kmalloc_addr = &link_mem_end;
+
+static void *kmalloc_int(size_t sz, int align, void **phys)
+{
+    if(align)
+    {
+        kmalloc_addr += (PAGE_SIZE - 1);
+        kmalloc_addr &= PAGE_MASK;
+    }
+    if(phys)
+        *phys = (void*)kmalloc_addr;
+    void *ret = (void*)kmalloc_addr;
+    kmalloc_addr += sz;
+    assert(((uint32_t)ret & 0xFFF) == 0);
+    return ret;
+}
+
+void *kmalloc(size_t sz)
+{
+    return kmalloc_int(sz, 0, NULL);
+}
+
+void *kmalloc_a(size_t sz)
+{
+    return kmalloc_int(sz, 1, NULL);
+}
+
+void *kmalloc_p(size_t sz, void **phys)
+{
+     return kmalloc_int(sz, 0, phys);
+}
+
+void *kmalloc_ap(size_t sz, void **phys)
+{
+    return kmalloc_int(sz, 1, phys);
+}