Index: trunk/CHANGES
===================================================================
--- trunk/CHANGES	(revision 255)
+++ trunk/CHANGES	(revision 256)
@@ -1,3 +1,4 @@
+- md0 code. Notified xnu when an md ramdisk is specified
 - Optimized memory detection speed
 - Added displaying source device and partition number for file read operations.
 - Increased boot2's maximum size from 383.5k to 447.5k.
Index: trunk/i386/boot2/ramdisk.h
===================================================================
--- trunk/i386/boot2/ramdisk.h	(revision 255)
+++ trunk/i386/boot2/ramdisk.h	(revision 256)
@@ -8,7 +8,15 @@
 #define __BOOT_RAMDISK_H
 
 #define RAMDISKCONFIG_FILENAME "rd(0,0)/RAMDisk.plist"
+//#define kPostbootRamdisk
+void md0Ramdisk();
 
+typedef struct RAMDiskParam
+{
+	ppnum_t base;
+	unsigned int size;
+} RAMDiskParam;
+
 /* mboot.c */
 extern struct multiboot_info *gMI;
 extern int multibootRamdiskReadBytes( int biosdev, unsigned int blkno,
Index: trunk/i386/boot2/boot.c
===================================================================
--- trunk/i386/boot2/boot.c	(revision 255)
+++ trunk/i386/boot2/boot.c	(revision 256)
@@ -162,6 +162,8 @@
 
     setupFakeEfi();
 
+    md0Ramdisk();
+
     verbose("Starting Darwin %s\n",( archCpuType == CPU_TYPE_I386 ) ? "x86" : "x86_64");
 
     // Cleanup the PXE base code.
Index: trunk/i386/boot2/boot.h
===================================================================
--- trunk/i386/boot2/boot.h	(revision 255)
+++ trunk/i386/boot2/boot.h	(revision 256)
@@ -92,6 +92,7 @@
 #define kLegacyOff			"USBLegacyOff"		/* usb.c */
 #define kEHCIhard			"EHCIhard"			/* usb.c */
 #define kDefaultPartition	"Default Partition"	/* sys.c */
+#define kMD0Image			"md0"				/* ramdisk.h */
 
 /*
  * Flags to the booter or kernel
Index: trunk/i386/boot2/ramdisk.c
===================================================================
--- trunk/i386/boot2/ramdisk.c	(revision 255)
+++ trunk/i386/boot2/ramdisk.c	(revision 256)
@@ -16,6 +16,89 @@
 bool gRAMDiskBTAliased = false;
 char gRAMDiskFile[512];
 
+
+// Notify OS X that a ramdisk has been setup. XNU with attach this to /dev/md0
+void md0Ramdisk()
+{
+	RAMDiskParam ramdiskPtr;
+	char filename[512];
+	const char* override_filename = 0;
+	int fh = -1;
+	int len;
+	
+	if(getValueForKey(kMD0Image, &override_filename, &len,  
+				   &bootInfo->bootConfig))
+	{
+		// Use user specified md0 file
+		sprintf(filename, "%s", override_filename);
+		fh = open(filename, 0);
+		
+		if(fh < 0)
+		{
+			sprintf(filename, "rd(0,0)/Extra/%s", override_filename);
+			if((fh = open(filename, 0)) < 0)
+			{
+				sprintf(filename, "/Extra/%s", override_filename);
+				fh = open(filename, 0);
+				
+			}
+		}		
+	}
+	
+	
+	if(fh < 0)
+	{
+		// Fallback to Postboot.img
+		sprintf(filename, "rd(0,0)/Extra/Postboot.img");
+		fh = open(filename, 0);
+		if(fh < 0)
+		{
+			sprintf(filename, "/Extra/Postboot.img");	// Check /Extra if not in rd(0,0)
+			fh = open(filename, 0);
+			
+		}
+	}		
+	
+	if (fh >= 0)
+	{
+		verbose("Enabling ramdisk %s\n", filename);
+
+		ramdiskPtr.size  = file_size(fh);
+		ramdiskPtr.base = AllocateKernelMemory(ramdiskPtr.size);
+		
+		if(ramdiskPtr.size && ramdiskPtr.base)
+		{
+			// Read new ramdisk image contents in kernel memory.
+			if (read(fh, (char*) ramdiskPtr.base, ramdiskPtr.size) == ramdiskPtr.size)
+			{
+				AllocateMemoryRange("RAMDisk", ramdiskPtr.base, ramdiskPtr.size, kBootDriverTypeInvalid);
+				Node* node = DT__FindNode("/chosen/memory-map", false);
+				if(node != NULL)
+				{
+					DT__AddProperty(node, "RAMDisk", sizeof(RAMDiskParam),  (void*)&ramdiskPtr);		
+					
+				}
+				else
+				{
+					verbose("Unable to notify Mac OS X of the ramdisk %s.\n", filename);
+				}
+				
+			}
+			else {
+				verbose("Unable to read md0 image %s.\n", filename);
+			}
+			
+		} else {
+			verbose("md0 image %s is empty.\n", filename);
+		}
+		
+		
+		close(fh);
+		
+	}
+}
+
+
 void umountRAMDisk()
 {
   if (gRAMDiskMI != NULL)