kmalloc: Initial (extremely buggy) implementation from liballoc

1 files changed, 47 insertions, 0 deletions

diff --git a/kernel/include/libk/kmalloc.h b/kernel/include/libk/kmalloc.h
new file mode 100644
index 0000000..f760ee1
--- /dev/null
+++ b/kernel/include/libk/kmalloc.h
@@ -0,0 +1,47 @@
+/*
+ * bubbl
+ * Copyright (C) 2025  Raghuram Subramani <raghus2247@gmail.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __libk_kmalloc_h
+#define __libk_kmalloc_h
+
+#include <stddef.h>
+
+void *kmalloc(size_t);
+void *krealloc(void *, size_t);
+void *kcalloc(size_t, size_t);
+void kfree(void *);
+
+/** This is a boundary tag which is prepended to the
+ * page or section of a page which we have allocated. It is
+ * used to identify valid memory blocks that the
+ * application is trying to free.
+ */
+struct boundary_tag {
+  unsigned int magic;     //< It's a kind of ...
+  unsigned int size;      //< Requested size.
+  unsigned int real_size; //< Actual size.
+  int index;              //< Location in the page table.
+
+  struct boundary_tag *split_left;  //< Linked-list info for broken pages.
+  struct boundary_tag *split_right; //< The same.
+
+  struct boundary_tag *next; //< Linked list info.
+  struct boundary_tag *prev; //< Linked list info.
+};
+
+#endif