Initial commit, with incomplete header file

include/slab.h

@@ -0,0 +1,50 @@
+#ifndef KARLOS_SLAB_H
+#define KARLOS_SLAB_H
+
+#include <stdint.h>
+#include <stddef.h>
+#include <paging.h>       
+
+/* Forward declaration of per-page descriptor */
+typedef struct slab_page slab_page_t;
+
+/*------------------------------------------------------------------------*/
+/* Per-cache descriptor: one cache per object size                       */
+/*------------------------------------------------------------------------*/
+typedef struct slab_cache {
+    size_t        obj_size;         // bytes per object
+    size_t        slots_per_slab;   // = PAGE_SIZE / obj_size
+    slab_page_t  *empty_slabs;      // slabs with all slots free
+    slab_page_t  *partial_slabs;    // slabs with some free slots
+    slab_page_t  *full_slabs;       // slabs with no free slots
+    void        (*constructor)(void *obj, size_t size);
+    void        (*destructor)(void *obj, size_t size);
+} slab_cache_t;
+
+/*------------------------------------------------------------------------*/
+/* Per-slab descriptor: one page carved into fixed-size slots            */
+/*------------------------------------------------------------------------*/
+typedef struct slab_page {
+    void          **free_stack;     // stack of free slots in this page
+    size_t          free_index;     // current head of stack (also free_count)
+    size_t          free_count;     // how many slots are free right now
+    void           *page_base;      // base address of the slab's page
+    struct slab_page *next;         // link to next slab_page in cache list
+} slab_page_t;
+
+/*------------------------------------------------------------------------*/
+/* API: implemented in KARLOS_SLAB.c                                    */
+/*------------------------------------------------------------------------*/
+slab_cache_t *slab_cache_create(
+    size_t obj_size,
+    size_t align,
+    void (*constructor)(void*, size_t),
+    void (*destructor)(void*, size_t)
+);
+
+void *slab_alloc(slab_cache_t *cache);
+void  slab_free(slab_cache_t *cache, void *obj);
+void  slab_destroy(slab_cache_t *cache);
+
+#endif /* KARLOS_SLAB_H */
+