From e52dd571d91ad59cf5e0197da51fc309b1183e8e Mon Sep 17 00:00:00 2001
From: Augustin Cavalier <waddlesplash@gmail.com>
Date: Mon, 16 Dec 2024 13:36:03 -0500
Subject: [PATCH] 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           | 15 ++++++++++-----
 src/system/boot/loader/heap.cpp              |  2 +-
 src/system/boot/loader/main.cpp              |  6 +++---
 src/system/boot/platform/bios_ia32/long.cpp  |  2 ++
 src/system/boot/platform/bios_ia32/start.cpp |  1 +
 5 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/headers/private/kernel/boot/heap.h b/headers/private/kernel/boot/heap.h
index 9f972c3eb1..ce49865e54 100644
--- a/headers/private/kernel/boot/heap.h
+++ b/headers/private/kernel/boot/heap.h
@@ -1,23 +1,28 @@
 /*
-** Copyright 2003, Axel Dörfler, axeld@pinc-software.de. All rights reserved.
-** Distributed under the terms of the MIT License.
-*/
+ * Copyright 2003, Axel Dörfler, axeld@pinc-software.de. All rights reserved.
+ * 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 */
diff --git a/src/system/boot/loader/heap.cpp b/src/system/boot/loader/heap.cpp
index c7ec5002cd..7efd5e3f5e 100644
--- a/src/system/boot/loader/heap.cpp
+++ b/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();
 
diff --git a/src/system/boot/loader/main.cpp b/src/system/boot/loader/main.cpp
index 98e84670dd..230dd59a1b 100644
--- a/src/system/boot/loader/main.cpp
+++ b/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.
-			heap_print_statistics();
+				// Further cleanup (e.g. heap_release) is the platform's responsibility.
+
 			platform_start_kernel();
 		}
 	}
 
 out:
-	heap_release(args);
+	heap_release();
 	return 0;
 }
diff --git a/src/system/boot/platform/bios_ia32/long.cpp b/src/system/boot/platform/bios_ia32/long.cpp
index 1c48f7ba0c..4cee5d2d81 100644
--- a/src/system/boot/platform/bios_ia32/long.cpp
+++ b/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.
diff --git a/src/system/boot/platform/bios_ia32/start.cpp b/src/system/boot/platform/bios_ia32/start.cpp
index 152f7a4b0f..7477853bd0 100644
--- a/src/system/boot/platform/bios_ia32/start.cpp
+++ b/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;