X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/5d5c5d0d5b79ade9a973d55186ffda2638ba2b6e..143464d58d2bd6378e74eec636961ceb0d32fb91:/osfmk/i386/asm64.h

diff --git a/osfmk/i386/asm64.h b/osfmk/i386/asm64.h
index 037573db8..b576f792d 100644
--- a/osfmk/i386/asm64.h
+++ b/osfmk/i386/asm64.h
@@ -1,64 +1,57 @@
 /*
- * Copyright (c) 2006 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2006-2012 Apple Inc. All rights reserved.
  *
- * @APPLE_LICENSE_OSREFERENCE_HEADER_START@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * 
- * This file contains Original Code and/or Modifications of Original Code 
- * as defined in and that are subject to the Apple Public Source License 
- * Version 2.0 (the 'License'). You may not use this file except in 
- * compliance with the License.  The rights granted to you under the 
- * License may not be used to create, or enable the creation or 
- * redistribution of, unlawful or unlicensed copies of an Apple operating 
- * system, or to circumvent, violate, or enable the circumvention or 
- * violation of, any terms of an Apple operating system software license 
- * agreement.
- *
- * Please obtain a copy of the License at 
- * http://www.opensource.apple.com/apsl/ and read it before using this 
- * file.
- *
- * The Original Code and all software distributed under the License are 
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 
- * Please see the License for the specific language governing rights and 
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ * 
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ * 
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
  * limitations under the License.
- *
- * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
+ * 
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 
 /* Helper macros for 64-bit mode switching */
 
+
 /*
  * Long jump to 64-bit space from 32-bit compatibility mode.
+ * Effected, in fact, by a long return ..
+ *  - we push the 64-bit kernel code selector KERNEL64_CS
+ *  - call .+1 to get EIP on stack
+ *  - adjust return address after lret
+ *  - lret to return to next instruction but 64-bit mode.
  */
 #define	ENTER_64BIT_MODE()			\
-	.code32					;\
-	.byte   0xea	/* far jump longmode */	;\
-	.long   1f				;\
-	.word   KERNEL64_CS			;\
-        .code64					;\
-1:
-
-/*
- * Here in long mode but still running below 4G.
- * "Near" jump into uber-space.
- */
-#define	ENTER_UBERSPACE()			\
-        mov     2f,%rax				;\
-        jmp     *%rax				;\
-2:      .long   3f				;\
-        .long   KERNEL_UBER_BASE_HI32		;\
-3:     
+	push	$KERNEL64_CS			;\
+	call    1f				;\
+1:	addl    $(2f-1b), (%esp)		;\
+	lret					;\
+2:	.code64
 
 /*
  * Long jump to 32-bit compatibility mode from 64-bit space.
+ * Effected by long return similar to ENTER_64BIT_MODE.
  */
 #define ENTER_COMPAT_MODE()			\
-	ljmp	*4f				;\
-4:	.long	5f				;\
-	.word	KERNEL_CS			;\
-	.code32					;\
-5:
+	call	3f				;\
+3:	addq	$(4f-3b), (%rsp)		;\
+	movl	$KERNEL32_CS, 4(%rsp)		;\
+	lret					;\
+4:	.code32