kernel: mem: add a simple kmalloc implementation

Add a simple implementation of kmalloc. This system only works on
x86-based processors at the time of commit.

Signed-off-by: Danny Holman <dholman@gymli.org>

2 files changed, 32 insertions, 0 deletions

diff --git a/include/kernel/mem.h b/include/kernel/mem.h
new file mode 100644
index 0000000..cf162ab
--- /dev/null
+++ b/include/kernel/mem.h
@@ -0,0 +1,9 @@
+#ifndef MEM_H
+
+#include <kernel/alloc.h>
+#include <kernel/paging.h>
+#include <stddef.h>
+
+void* kmalloc(size_t sz);
+
+#endif
diff --git a/kernel/mem.c b/kernel/mem.c
new file mode 100644
index 0000000..e2f1889
--- /dev/null
+++ b/kernel/mem.c
@@ -0,0 +1,23 @@
+#include <kernel/mem.h>
+#include <kernel/alloc.h>
+#include <kernel/paging.h>
+
+extern uint32_t _kernel_end;
+static uint32_t *heap_start = &_kernel_end;
+static uint32_t *heap_end = &_kernel_end;
+
+int _alloc_new_page(void) {
+        uint32_t paddr = pfa_alloc_frame();
+        if (paddr == 0xFFFFFFFF)
+                return -1;
+        map_page(paddr, heap_end, 0x003);
+}
+
+void* kmalloc(size_t sz) {
+        void *ret = heap_end;
+        heap_end += sz;
+        return ret;
+}
+
+void kfree(void *ptr) {
+}