inc/cdef.h

@@ -13,6 +13,7 @@ typedef uint16_t uint16;
 typedef int16_t int16;
 typedef uint8_t uint8;
 typedef int8_t int8;
+typedef size_t usize;
 
 typedef _Bool bool;
 #define TRUE (1)

kernel/lb/ssalloc.c

@@ -0,0 +1,104 @@
+#include "cdef.h"
+#include "mlayout.h"
+#include "lb/dlist.h"
+
+/**
+ * Simplified Slab Allocator
+ */
+
+#define LARGE_THRESHOLD (8)
+
+struct ssalloc_page_desc
+{
+    struct dlist_node node;
+    uint32 used_obj_num;
+    uint8 free_list[0]; /* free list inside each slab */
+};
+
+struct ssalloc_obj_desc
+{
+    struct dlist free_list;
+    struct dlist full_list;
+    struct dlist empty_list;
+    usize obj_size;
+    uint32 align;
+};
+
+struct ssalloc_desc
+{
+    uint32 chunk_size;
+    void* malloc_chunk(void);   // allocate a chunk
+    void* free_chunk(void);     // free a chunk
+};
+
+static void* scalloc_large(struct ssalloc_desc* desc, struct ssalloc_obj_desc* obj_desc)
+{
+
+}
+
+static void scfree_large(struct ssalloc_desc* desc, struct ssalloc_obj_desc* obj_desc, void* addr)
+{
+
+}
+
+static void* scalloc_small(struct ssalloc_desc* desc, struct ssalloc_obj_desc* obj_desc)
+{
+    // check the current free list first
+    if (lb_dlist_size(&obj_desc->free_list) > 0)
+    {
+        // if it exists then we grab something from the list
+        struct llist_node* node = lb_dlist_first(node);
+    }
+    else
+    {
+
+    }
+}
+
+static void scfree_small(struct ssalloc_desc* desc, struct ssalloc_obj_desc* obj_desc, void* addr)
+{
+
+}
+
+void ssalloc_desc_init(struct ssalloc_desc* desc)
+{
+
+}
+
+void ssalloc_obj_desc_init(struct ssalloc_obj_desc* obj_desc, usize obj_size, uint32 align)
+{
+    obj_desc->obj_size = obj_size;
+    obj_desc->align = align;
+    lb_dlist_init(&obj_desc->empty_list);
+    lb_dlist_init(&obj_desc->full_list);
+    lb_dlist_init(&obj_desc->free_list);
+}
+
+void* scalloc(struct ssalloc_desc* desc, struct ssalloc_obj_desc* obj_desc)
+{
+    void* ret = NULL;
+    if(obj_desc->obj_size < desc->chunk_size / LARGE_THRESHOLD)
+    {
+        ret = scalloc_small(desc, obj_desc);
+    }
+    else
+    {
+        // large objects
+        ret = scalloc_large(desc, obj_desc);
+    }
+
+    return ret;
+}
+
+void scfree(struct ssalloc_desc* desc, struct ssalloc_obj_desc* obj_desc, void* address)
+{
+    if(obj_desc->obj_size < desc->chunk_size)
+    {
+        scfree_small(desc, obj_desc, address);
+    }
+    else
+    {
+        // large objects
+        scfree_large(desc, obj_desc, address);
+    }
+}