build system and some other stuff

1 files changed, 40 insertions, 0 deletions

diff --git a/sys/kern/mm/kalloc.c b/sys/kern/mm/kalloc.c
new file mode 100644
index 0000000..b17d432
--- /dev/null
+++ b/sys/kern/mm/kalloc.c
@@ -0,0 +1,40 @@
+#include <stddef.h>
+#include <string.h>
+#include <mm/kalloc.h>
+
+typedef struct freenode {
+	struct freenode *next;
+} freenode_t;
+
+freenode_t *head = NULL;
+
+void *
+kalloc(void) 
+{
+	freenode_t *p = head;
+
+	if (p == NULL)
+		return NULL;
+
+	head = p->next;
+	return p;
+}
+
+void *
+kzalloc(void)
+{
+	freenode_t *p = kalloc();
+	memset(p, 0, PAGE_SIZE);
+	return p;
+}
+
+void
+kfree(void *p)
+{
+	if (p == NULL || (unsigned long)p % PAGE_SIZE)
+		return;
+
+	freenode_t *tmp = head;
+	head = p;
+	head->next = tmp;
+}