From 301b2d40f0f2604a698198142a1f420b737e56d4 Mon Sep 17 00:00:00 2001
From: Michael Brown <mcb30@etherboot.org>
Date: Fri, 13 May 2005 13:30:51 +0000
Subject: [PATCH] Use the heap functions to allocate a load buffer.

---
 src/arch/i386/core/load_buffer.c | 103 ++++++++++++++++---------------
 1 file changed, 52 insertions(+), 51 deletions(-)

diff --git a/src/arch/i386/core/load_buffer.c b/src/arch/i386/core/load_buffer.c
index 1668b3c5..78cdb9af 100644
--- a/src/arch/i386/core/load_buffer.c
+++ b/src/arch/i386/core/load_buffer.c
@@ -1,8 +1,6 @@
-#include "limits.h"
 #include "io.h"
-#include "memsizes.h"
-#include "init.h"
-#include "buffer.h"
+#include "heap.h"
+#include "load_buffer.h"
 
 /*
  * Initialise a buffer in an unused portion of memory, to be used for
@@ -10,55 +8,58 @@
  *
  */
 
-/* Under KEEP_IT_REAL, always use 07c0:0000 as the buffer.  Otherwise,
- * use a reset_fn that finds the largest available block of RAM.
+#ifdef KEEP_IT_REAL
+
+/*
+ * Under KEEP_IT_REAL, always use 07c0:0000 as the load buffer.
+ *
  */
-struct buffer load_buffer = {
-	.start = 0x7c00,
-	.end = 0xa0000,
-};
 
-#ifndef KEEP_IT_REAL
-
-extern char _text[];
-
-static void init_load_buffer ( void ) {
-	unsigned int i;
-	unsigned long size = 0;
-
-	load_buffer.start = 0;
-	load_buffer.end = 0;
-
-	/* Find the largest usable segment in memory */
-	for ( i = 0 ; i < meminfo.map_count ; i++ ) {
-		unsigned long r_start, r_end;
-
-		if ( meminfo.map[i].type != E820_RAM )
-			continue;
-
-		if ( meminfo.map[i].addr + meminfo.map[i].size > ULONG_MAX )
-			continue;
-
-		r_start = meminfo.map[i].addr;
-		r_end = meminfo.map[i].size;
-
-		/* Avoid overlap with Etherboot.  Etherboot will be
-		 * located towards the top of a segment, so we need
-		 * only consider one-sided truncation.
-		 */
-		if ( ( r_start <= virt_to_phys ( _text ) ) &&
-		     ( virt_to_phys ( _text ) < r_end ) ) {
-			r_end = virt_to_phys ( _text );
-		}
-
-		if ( r_end - r_start > size ) {
-			size = r_end - r_start;
-			load_buffer.start = r_start;
-			load_buffer.end = r_end;
-		}
-	}
+int init_load_buffer ( struct buffer *buffer ) {
+	buffer->start = 0x7c00;
+	buffer->end = 0xa0000;
+	init_buffer ( buffer );
+	return 1;
+}
+
+void trim_load_buffer ( struct buffer *buffer ) {
+	/* Nothing to do */
+}
+
+void done_load_buffer ( struct buffer *buffer ) {
+	/* Nothing to do */
+}
+
+#else /* KEEP_IT_REAL */
+
+/*
+ * Without KEEP_IT_REAL, use all remaining heap space as the load buffer.
+ *
+ */
+int init_load_buffer ( struct buffer *buffer ) {
+	void *data;
+	size_t size;
+	
+	data = emalloc_all ( &size );
+	if ( ! data )
+		return 0;
+
+	buffer->start = virt_to_phys ( data );
+	buffer->end = buffer->start + size;
+	init_buffer ( buffer );
+	return 1;
+}
+
+void trim_load_buffer ( struct buffer *buffer ) {
+	void *new_start;
+
+	/* Shrink buffer */
+	new_start = erealloc ( phys_to_virt ( buffer->start ), buffer->fill );
+	buffer->start = virt_to_phys ( new_start );
+}
+
+void done_load_buffer ( struct buffer *buffer ) {
+	efree ( phys_to_virt ( buffer->start ) );
 }
 
-INIT_FN ( INIT_HEAP, init_load_buffer, init_load_buffer, NULL );
-		 
 #endif