--- a/src/core/ngx_slab.h
+++ b/src/core/ngx_slab.h
@@ -12,32 +12,34 @@
 #include <ngx_core.h>
 
 
-typedef struct ngx_free_slab_s  ngx_free_slab_t;
-
-typedef struct ngx_free_slab_s {
-    ngx_free_slab_t  *next;
-}
-
+typedef struct ngx_slab_page_s  ngx_slab_page_t;
 
-typedef struct ngx_slab_block_s  ngx_slab_block_t;
-
-typedef struct ngx_slab_block_s {
-    ngx_free_slab_t  *free;
-    ngx_slab_buf_t   *next;
-    size_t            color;
+struct ngx_slab_page_s {
+    uintptr_t         slab;
+    ngx_slab_page_t  *next;
+    uintptr_t         prev;
 };
 
 
 typedef struct {
-    ngx_slab_buf_t   *blocks;
-    size_t            size;
+    ngx_atomic_t      lock;
+
+    size_t            min_size;
+    size_t            min_shift;
 
-    void             *start;
-    uint32_t          map;
+    ngx_slab_page_t  *pages;
+    ngx_slab_page_t   free;
 
-    ngx_log_t        *log;
-    ngx_free_pool_t   free;
+    u_char           *start;
+    u_char           *end;
+
+    ngx_shmtx_t       mutex;
 } ngx_slab_pool_t;
 
 
+void ngx_slab_init(ngx_slab_pool_t *pool);
+void *ngx_slab_alloc(ngx_slab_pool_t *pool, size_t size);
+void ngx_slab_free(ngx_slab_pool_t *pool, void *p);
+
+
 #endif /* _NGX_SLAB_H_INCLUDED_ */