stos: pool: Add actual allocation groundwork

Still lots to do

Signed-off-by: Chloe M. <chloe@mensia.org>

paw/stos/head/ex/pool.h

@@ -13,9 +13,12 @@
 #include <stapi/status.h>
 #include <stdef.h>
 
+/* Minimum log2 allocation size */
+#define POOL_MIN_LOG2 3
+
 /* Compute the granularity of a specific level */
 #define LEVEL_GRAN(LEVEL) \
-    (1 << (3 + (LEVEL)))
+    (1 << (POOL_MIN_LOG2 + (LEVEL)))
 
 /* Maximum levels per pool */
 #define LEVEL_COUNT 8
@@ -28,6 +31,15 @@
 #define POOL_REAL_PAGESZ \
     (PAGESIZE - sizeof(MEMORY_PAGE))
 
+/*
+ * Valid pool types
+ *
+ * @POOL_NON_PAGED: Not pagable to disk
+ */
+typedef enum {
+    POOL_NON_PAGED
+} POOL_TYPE;
+
 /*
  * Page data structure used internally to link together page
  * lists
@@ -58,9 +70,11 @@ typedef struct {
  * A memory pool holds blocks of varying granularities
  *
  * @BlockLevels: Block levels [granularity : GRAN(level)]
+ * @Id:          Pool ID
  */
 typedef struct {
     MEMORY_BLOCK BlockLevels[LEVEL_COUNT];
+    USIZE Id;
 } MEMORY_POOL;
 
 /*
@@ -70,4 +84,19 @@ typedef struct {
  */
 ST_STATUS ExPoolInit(MEMORY_POOL *Pool);
 
+/*
+ * Allocate a tagged pool
+ *
+ * @Type:       Pool type
+ * @ByteCount:  Number of bytes to allocate
+ * @Tag:        Tag to assign to pool
+ *
+ * Returns the memory base on success, otherwise
+ * NULL on failure.
+ */
+VOID *ExAllocatePoolWithTag(
+    POOL_TYPE Type, USIZE ByteCount,
+    ULONG Tag
+);
+
 #endif  /* !_EX_POOL_H_ */