EFI: Implement heap

src/system/boot/platform/efi/heap.cpp

@@ -7,16 +7,34 @@
 #include <boot/platform.h>
 #include <boot/stage2.h>
 
+#include "efi_platform.h"
+
+
+#define STAGE_PAGES	0x2000 /* 32 MB */
+
+
+static EFI_PHYSICAL_ADDRESS staging;
+
 
 extern "C" void
 platform_release_heap(struct stage2_args *args, void *base)
 {
-	return;
+	if ((void*)staging != base)
+		panic("Attempt to release heap with wrong base address!");
+
+	kBootServices->FreePages(staging, STAGE_PAGES);
 }
 
 
 extern "C" status_t
 platform_init_heap(struct stage2_args *args, void **_base, void **_top)
 {
-	return B_ERROR;
+	if (kBootServices->AllocatePages(AllocateAnyPages, EfiLoaderData,
+			STAGE_PAGES, &staging) != EFI_SUCCESS)
+		return B_NO_MEMORY;
+
+	*_base = (void*)staging;
+	*_top = (void*)((int8*)staging + STAGE_PAGES * PAGE_SIZE);
+
+	return B_OK;
 }