bootloader: Make releasing the heap the platform loader's responsibility.

Otherwise, platform loaders couldn't make heap allocations inside
platform_start_kernel(), which some loaders (e.g. EFI) do.

Implement calling heap_release() for the BIOS loaders at least.
This gets us back the ~1.5MB of bootloader heap memory there.

headers/private/kernel/boot/heap.h

@@ -1,23 +1,28 @@
 /*
-** Copyright 2003, Axel Dörfler, [email protected]. All rights reserved.
+ * Copyright 2003, Axel Dörfler, [email protected]. All rights reserved.
-** Distributed under the terms of the MIT License.
+ * Distributed under the terms of the MIT License.
-*/
+ */
 #ifndef KERNEL_BOOT_HEAP_H
 #define KERNEL_BOOT_HEAP_H
 
+
 #include <SupportDefs.h>
 #include <boot/stage2_args.h>
 
+
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-extern void heap_release(struct stage2_args *args);
+
-extern void heap_print_statistics();
 extern status_t heap_init(struct stage2_args *args);
+extern void heap_print_statistics();
+extern void heap_release();
+
 
 #ifdef __cplusplus
 }
 #endif
 
+
 #endif	/* KERNEL_BOOT_HEAP_H */

src/system/boot/loader/heap.cpp

@@ -383,7 +383,7 @@ FreeChunk::SetToAllocated(void* allocated)
 
 
 void
-heap_release(stage2_args* args)
+heap_release()
 {
 	heap_print_statistics();
 

src/system/boot/loader/main.cpp

@@ -161,13 +161,13 @@ main(stage2_args *args)
 			gKernelArgs.boot_volume_size = gBootVolume.ContentSize();
 
 			platform_cleanup_devices();
-			// TODO: cleanup, heap_release() etc.
+				// Further cleanup (e.g. heap_release) is the platform's responsibility.
-			heap_print_statistics();
+
 			platform_start_kernel();
 		}
 	}
 
 out:
-	heap_release(args);
+	heap_release();
 	return 0;
 }

src/system/boot/platform/bios_ia32/long.cpp

@@ -354,6 +354,8 @@ long_start_kernel()
 	long_gdt_init();
 	debug_cleanup();
 	long_mmu_init();
+	heap_release();
+
 	convert_kernel_args();
 
 	// Save the kernel entry point address.

src/system/boot/platform/bios_ia32/start.cpp

@@ -139,6 +139,7 @@ platform_start_kernel(void)
 	smp_init_other_cpus();
 	debug_cleanup();
 	mmu_init_for_kernel();
+	heap_release();
 
 	// We're about to enter the kernel -- disable console output.
 	stdout = NULL;