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

/*
 * Copyright (c) 2000-2002 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_OSREFERENCE_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 
 * limitations under the License.
 *
 * @APPLE_LICENSE_OSREFERENCE_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	_MACH_VM_PROT_H_
#define	_MACH_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	/* _MACH_VM_PROT_H_ */
Commit	Line	Data
1c79356b	1	/*
9bccf70c	2	* Copyright (c) 2000-2002 Apple Computer, Inc. All rights reserved.
1c79356b	3	*
8ad349bb	4	* @APPLE_LICENSE_OSREFERENCE_HEADER_START@
1c79356b	5	*
8ad349bb A	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the
	10	* License may not be used to create, or enable the creation or
	11	* redistribution of, unlawful or unlicensed copies of an Apple operating
	12	* system, or to circumvent, violate, or enable the circumvention or
	13	* violation of, any terms of an Apple operating system software license
	14	* agreement.
	15	*
	16	* Please obtain a copy of the License at
	17	* http://www.opensource.apple.com/apsl/ and read it before using this
	18	* file.
	19	*
	20	* The Original Code and all software distributed under the License are
	21	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	22	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	23	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	24	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	25	* Please see the License for the specific language governing rights and
	26	* limitations under the License.
	27	*
	28	* @APPLE_LICENSE_OSREFERENCE_HEADER_END@
1c79356b A	29	*/
	30	/*
	31	* @OSF_COPYRIGHT@
	32	*/
1c79356b A	33	/*
	34	* Mach Operating System
	35	* Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
	36	* All Rights Reserved.
	37	*
	38	* Permission to use, copy, modify and distribute this software and its
	39	* documentation is hereby granted, provided that both the copyright
	40	* notice and this permission notice appear in all copies of the
	41	* software, derivative works or modified versions, and any portions
	42	* thereof, and that both notices appear in supporting documentation.
	43	*
	44	* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
	45	* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
	46	* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
	47	*
	48	* Carnegie Mellon requests users of this software to return to
	49	*
	50	* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
	51	* School of Computer Science
	52	* Carnegie Mellon University
	53	* Pittsburgh PA 15213-3890
	54	*
	55	* any improvements or extensions that they make and grant Carnegie Mellon
	56	* the rights to redistribute these changes.
	57	*/
	58	/*
	59	*/
	60	/*
	61	* File: mach/vm_prot.h
	62	* Author: Avadis Tevanian, Jr., Michael Wayne Young
	63	*
	64	* Virtual memory protection definitions.
	65	*
	66	*/
	67
91447636 A	68	#ifndef _MACH_VM_PROT_H_
91447636 A	69	#define _MACH_VM_PROT_H_
1c79356b A	70
	71	/*
	72	* Types defined:
	73	*
	74	* vm_prot_t VM protection values.
	75	*/
	76
	77	typedef int vm_prot_t;
	78
	79	/*
	80	* Protection values, defined as bits within the vm_prot_t type
	81	*/
	82
	83	#define VM_PROT_NONE ((vm_prot_t) 0x00)
	84
	85	#define VM_PROT_READ ((vm_prot_t) 0x01) /* read permission */
	86	#define VM_PROT_WRITE ((vm_prot_t) 0x02) /* write permission */
	87	#define VM_PROT_EXECUTE ((vm_prot_t) 0x04) /* execute permission */
	88
	89	/*
	90	* The default protection for newly-created virtual memory
	91	*/
	92
	93	#define VM_PROT_DEFAULT (VM_PROT_READ\|VM_PROT_WRITE)
	94
	95	/*
	96	* The maximum privileges possible, for parameter checking.
	97	*/
	98
	99	#define VM_PROT_ALL (VM_PROT_READ\|VM_PROT_WRITE\|VM_PROT_EXECUTE)
	100
	101	/*
	102	* An invalid protection value.
	103	* Used only by memory_object_lock_request to indicate no change
	104	* to page locks. Using -1 here is a bad idea because it
	105	* looks like VM_PROT_ALL and then some.
	106	*/
91447636	107
1c79356b A	108	#define VM_PROT_NO_CHANGE ((vm_prot_t) 0x08)
	109
	110	/*
	111	* When a caller finds that he cannot obtain write permission on a
	112	* mapped entry, the following flag can be used. The entry will
	113	* be made "needs copy" effectively copying the object (using COW),
	114	* and write permission will be added to the maximum protections
	115	* for the associated entry.
	116	*/
91447636	117
1c79356b A	118	#define VM_PROT_COPY ((vm_prot_t) 0x10)
	119
	120
	121	/*
	122	* Another invalid protection value.
	123	* Used only by memory_object_data_request upon an object
	124	* which has specified a copy_call copy strategy. It is used
	125	* when the kernel wants a page belonging to a copy of the
	126	* object, and is only asking the object as a result of
	127	* following a shadow chain. This solves the race between pages
	128	* being pushed up by the memory manager and the kernel
	129	* walking down the shadow chain.
	130	*/
91447636	131
1c79356b A	132	#define VM_PROT_WANTS_COPY ((vm_prot_t) 0x10)
1c79356b A	133
91447636	134	#endif /* _MACH_VM_PROT_H_ */