From ff8d4f287fb443b3880bcebb2823505b37207600 Mon Sep 17 00:00:00 2001
From: ripsaw8080 <ripsaw8080@users.sourceforge.net>
Date: Tue, 12 Jun 2018 20:18:42 +0000
Subject: [PATCH] More improvements for IOCTL generic block device request

Imported-from: https://svn.code.sf.net/p/dosbox/code-0/dosbox/trunk@4115
---
 src/dos/dos.cpp       |  8 +-------
 src/dos/dos_ioctl.cpp | 15 +++++++--------
 2 files changed, 8 insertions(+), 15 deletions(-)

diff --git a/src/dos/dos.cpp b/src/dos/dos.cpp
index 6338086c..2864fb02 100644
--- a/src/dos/dos.cpp
+++ b/src/dos/dos.cpp
@@ -1118,13 +1118,7 @@ static Bitu DOS_21Handler(void) {
 			}	
 			reg_ch=0x08;	// IOCTL category: disk drive
 			reg_ax=0x440d;	// Generic block device request
-			if (DOS_IOCTL()) {
-				reg_ax=0;	// AX destroyed
-				CALLBACK_SCF(false);
-			} else {
-				reg_ax=dos.errorcode;
-				CALLBACK_SCF(true);
-			}
+			DOS_21Handler();
 			reg_cx=old_cx;
 			break;
 		} 
diff --git a/src/dos/dos_ioctl.cpp b/src/dos/dos_ioctl.cpp
index 1357bd72..ad8ebe42 100644
--- a/src/dos/dos_ioctl.cpp
+++ b/src/dos/dos_ioctl.cpp
@@ -156,22 +156,20 @@ bool DOS_IOCTL(void) {
 				DOS_SetError(DOSERR_ACCESS_DENIED);
 				return false;
 			}
-			if (Drives[drive]->isRemovable()) {
+			if (reg_ch != 0x08 || Drives[drive]->isRemovable()) {
 				DOS_SetError(DOSERR_FUNCTION_NUMBER_INVALID);
 				return false;
 			}
 			PhysPt ptr	= SegPhys(ds)+reg_dx;
 			switch (reg_cl) {
 			case 0x60:		/* Get Device parameters */
-				mem_writeb(ptr  ,0x03);					// special function
-				mem_writeb(ptr+1,(drive>=2)?0x05:0x14);	// fixed disc(5), 1.44 floppy(14)
-				mem_writew(ptr+2,drive>=2);				// nonremovable ?
+				//mem_writeb(ptr+0,0);					// special functions (call value)
+				mem_writeb(ptr+1,(drive>=2)?0x05:0x07);	// type: hard disk(5), 1.44 floppy(7)
+				mem_writew(ptr+2,(drive>=2)?0x01:0x00);	// attributes: bit 0 set for nonremovable
 				mem_writew(ptr+4,0x0000);				// num of cylinders
 				mem_writeb(ptr+6,0x00);					// media type (00=other type)
-				// drive parameter block following
-				mem_writeb(ptr+7,drive);				// drive
-				mem_writeb(ptr+8,0x00);					// unit number
-				mem_writed(ptr+0x1f,0xffffffff);		// next parameter block
+				// bios parameter block following
+				mem_writew(ptr+7,0x0200);				// bytes per sector (Win3 File Mgr. uses it)
 				break;
 			case 0x46:	/* Set volume serial number */
 				break;
@@ -205,6 +203,7 @@ bool DOS_IOCTL(void) {
 				DOS_SetError(DOSERR_FUNCTION_NUMBER_INVALID);
 				return false;
 			}
+			reg_ax=0;
 			return true;
 		}
 	case 0x0E:			/* Get Logical Drive Map */