[apple/xnu.git] / osfmk / mach / vm_prot.h

/*
 * Copyright (c) 2000-2002 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
 * 
 * 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. 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_HEADER_END@
 */
/*
 * @OSF_COPYRIGHT@
 */
/* 
 * Mach Operating System
 * Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
 * All Rights Reserved.
 * 
 * Permission to use, copy, modify and distribute this software and its
 * documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 * 
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 * 
 * Carnegie Mellon requests users of this software to return to
 * 
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 * 
 * any improvements or extensions that they make and grant Carnegie Mellon
 * the rights to redistribute these changes.
 */
/*
 */
/*
 *	File:	mach/vm_prot.h
 *	Author:	Avadis Tevanian, Jr., Michael Wayne Young
 *
 *	Virtual memory protection definitions.
 *
 */

#ifndef	VM_PROT_H_
#define	VM_PROT_H_

/*
 *	Types defined:
 *
 *	vm_prot_t		VM protection values.
 */

typedef int		vm_prot_t;

/*
 *	Protection values, defined as bits within the vm_prot_t type
 */

#define	VM_PROT_NONE	((vm_prot_t) 0x00)

#define VM_PROT_READ	((vm_prot_t) 0x01)	/* read permission */
#define VM_PROT_WRITE	((vm_prot_t) 0x02)	/* write permission */
#define VM_PROT_EXECUTE	((vm_prot_t) 0x04)	/* execute permission */

/*
 *	The default protection for newly-created virtual memory
 */

#define VM_PROT_DEFAULT	(VM_PROT_READ|VM_PROT_WRITE)

/*
 *	The maximum privileges possible, for parameter checking.
 */

#define VM_PROT_ALL	(VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE)

/*
 *	An invalid protection value.
 *	Used only by memory_object_lock_request to indicate no change
 *	to page locks.  Using -1 here is a bad idea because it
 *	looks like VM_PROT_ALL and then some.
 */
#define VM_PROT_NO_CHANGE	((vm_prot_t) 0x08)

/* 
 *      When a caller finds that he cannot obtain write permission on a
 *      mapped entry, the following flag can be used.  The entry will
 *      be made "needs copy" effectively copying the object (using COW),
 *      and write permission will be added to the maximum protections
 *      for the associated entry. 
 */        
#define VM_PROT_COPY            ((vm_prot_t) 0x10)


/*
 *	Another invalid protection value.
 *	Used only by memory_object_data_request upon an object
 *	which has specified a copy_call copy strategy. It is used
 *	when the kernel wants a page belonging to a copy of the
 *	object, and is only asking the object as a result of
 *	following a shadow chain. This solves the race between pages
 *	being pushed up by the memory manager and the kernel
 *	walking down the shadow chain.
 */
#define VM_PROT_WANTS_COPY	((vm_prot_t) 0x10)

#endif	/* VM_PROT_H_ */
Commit	Line	Data
1c79356b	1	/*
9bccf70c	2	* Copyright (c) 2000-2002 Apple Computer, Inc. All rights reserved.
1c79356b A	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
43866e37	6	* Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
1c79356b	7	*
43866e37 A	8	* This file contains Original Code and/or Modifications of Original Code
	9	* as defined in and that are subject to the Apple Public Source License
	10	* Version 2.0 (the 'License'). You may not use this file except in
	11	* compliance with the License. Please obtain a copy of the License at
	12	* http://www.opensource.apple.com/apsl/ and read it before using this
	13	* file.
	14	*
	15	* The Original Code and all software distributed under the License are
	16	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
1c79356b A	17	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
1c79356b A	18	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
43866e37 A	19	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	20	* Please see the License for the specific language governing rights and
	21	* limitations under the License.
1c79356b A	22	*
	23	* @APPLE_LICENSE_HEADER_END@
	24	*/
	25	/*
	26	* @OSF_COPYRIGHT@
	27	*/
1c79356b A	28	/*
	29	* Mach Operating System
	30	* Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
	31	* All Rights Reserved.
	32	*
	33	* Permission to use, copy, modify and distribute this software and its
	34	* documentation is hereby granted, provided that both the copyright
	35	* notice and this permission notice appear in all copies of the
	36	* software, derivative works or modified versions, and any portions
	37	* thereof, and that both notices appear in supporting documentation.
	38	*
	39	* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
	40	* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
	41	* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
	42	*
	43	* Carnegie Mellon requests users of this software to return to
	44	*
	45	* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
	46	* School of Computer Science
	47	* Carnegie Mellon University
	48	* Pittsburgh PA 15213-3890
	49	*
	50	* any improvements or extensions that they make and grant Carnegie Mellon
	51	* the rights to redistribute these changes.
	52	*/
	53	/*
	54	*/
	55	/*
	56	* File: mach/vm_prot.h
	57	* Author: Avadis Tevanian, Jr., Michael Wayne Young
	58	*
	59	* Virtual memory protection definitions.
	60	*
	61	*/
	62
	63	#ifndef VM_PROT_H_
	64	#define VM_PROT_H_
	65
	66	/*
	67	* Types defined:
	68	*
	69	* vm_prot_t VM protection values.
	70	*/
	71
	72	typedef int vm_prot_t;
	73
	74	/*
	75	* Protection values, defined as bits within the vm_prot_t type
	76	*/
	77
	78	#define VM_PROT_NONE ((vm_prot_t) 0x00)
	79
	80	#define VM_PROT_READ ((vm_prot_t) 0x01) /* read permission */
	81	#define VM_PROT_WRITE ((vm_prot_t) 0x02) /* write permission */
	82	#define VM_PROT_EXECUTE ((vm_prot_t) 0x04) /* execute permission */
	83
	84	/*
	85	* The default protection for newly-created virtual memory
	86	*/
	87
	88	#define VM_PROT_DEFAULT (VM_PROT_READ\|VM_PROT_WRITE)
	89
	90	/*
	91	* The maximum privileges possible, for parameter checking.
92	*/
93
94	#define VM_PROT_ALL (VM_PROT_READ\|VM_PROT_WRITE\|VM_PROT_EXECUTE)
95
96	/*
97	* An invalid protection value.
98	* Used only by memory_object_lock_request to indicate no change
99	* to page locks. Using -1 here is a bad idea because it
100	* looks like VM_PROT_ALL and then some.
101	*/
102	#define VM_PROT_NO_CHANGE ((vm_prot_t) 0x08)
103
104	/*
105	* When a caller finds that he cannot obtain write permission on a
106	* mapped entry, the following flag can be used. The entry will
107	* be made "needs copy" effectively copying the object (using COW),
108	* and write permission will be added to the maximum protections
109	* for the associated entry.
110	*/
111	#define VM_PROT_COPY ((vm_prot_t) 0x10)
112
113
114	/*
115	* Another invalid protection value.
116	* Used only by memory_object_data_request upon an object
117	* which has specified a copy_call copy strategy. It is used
118	* when the kernel wants a page belonging to a copy of the
119	* object, and is only asking the object as a result of
120	* following a shadow chain. This solves the race between pages
121	* being pushed up by the memory manager and the kernel
122	* walking down the shadow chain.
123	*/
124	#define VM_PROT_WANTS_COPY ((vm_prot_t) 0x10)
125
126	#endif /* VM_PROT_H_ */