[apple/xnu.git] / osfmk / i386 / mp_desc.h

/*
 * Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved.
 *
 * @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
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/*
 * @OSF_COPYRIGHT@
 */
/* 
 * Mach Operating System
 * Copyright (c) 1991,1990 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.
 */

/*
 */

#ifndef	_I386_MP_DESC_H_
#define	_I386_MP_DESC_H_

#include <mach_kdb.h>
#include <sys/cdefs.h>

__BEGIN_DECLS

/*
 * Multiprocessor i386/i486 systems use a separate copy of the
 * GDT, IDT, LDT, and kernel TSS per processor.  The first three
 * are separate to avoid lock contention: the i386 uses locked
 * memory cycles to access the descriptor tables.  The TSS is
 * separate since each processor needs its own kernel stack,
 * and since using a TSS marks it busy.
 */

#include <i386/seg.h>
#include <i386/tss.h>

/*
 * The descriptor tables are together in a structure
 * allocated one per processor (except for the boot processor).
 * Note that dbtss could be conditionalized on MACH_KDB, but
 * doing so increases misconfiguration risk.
 */
struct mp_desc_table {
	struct fake_descriptor	idt[IDTSZ];	/* IDT */
	struct fake_descriptor	gdt[GDTSZ];	/* GDT */
	struct fake_descriptor	ldt[LDTSZ];	/* LDT */
	struct i386_tss		ktss;
	struct i386_tss		dbtss;
};

#define	current_gdt()	(current_cpu_datap()->cpu_desc_index.cdi_gdt)
#define	current_idt()	(current_cpu_datap()->cpu_desc_index.cdi_idt)
#define	current_ldt()	(current_cpu_datap()->cpu_desc_index.cdi_ldt)
#define	current_ktss()	(current_cpu_datap()->cpu_desc_index.cdi_ktss)
#define	current_dbtss()	(current_cpu_datap()->cpu_desc_index.cdi_dbtss)

#define	gdt_desc_p(sel) \
	((struct real_descriptor *)&current_gdt()[sel_idx(sel)])
#define	ldt_desc_p(sel) \
	((struct real_descriptor *)&current_ldt()[sel_idx(sel)])

extern void	mp_desc_init(cpu_data_t *cdp, boolean_t is_boot_cpu);

static inline boolean_t
valid_user_data_selector(uint16_t selector)
{
    sel_t	sel = selector_to_sel(selector);
    
    if (selector == 0)
    	return (TRUE);

    if (sel.ti == SEL_LDT)
	return (TRUE);
    else if (sel.index < GDTSZ) {
	if ((gdt_desc_p(selector)->access & ACC_PL_U) == ACC_PL_U)
	    return (TRUE);
    }
		
    return (FALSE);
}

static inline boolean_t
valid_user_code_selector(uint16_t selector)
{
    sel_t	sel = selector_to_sel(selector);
    
    if (selector == 0)
    	return (FALSE);

    if (sel.ti == SEL_LDT) {
	if (sel.rpl == USER_PRIV)
	    return (TRUE);
    }
    else if (sel.index < GDTSZ && sel.rpl == USER_PRIV) {
	if ((gdt_desc_p(selector)->access & ACC_PL_U) == ACC_PL_U)
	    return (TRUE);
    }

    return (FALSE);
}

static inline boolean_t
valid_user_stack_selector(uint16_t selector)
{
    sel_t	sel = selector_to_sel(selector);
    
    if (selector == 0)
    	return (FALSE);

    if (sel.ti == SEL_LDT) {
	if (sel.rpl == USER_PRIV)
	    return (TRUE);
    }
    else if (sel.index < GDTSZ && sel.rpl == USER_PRIV) {
	if ((gdt_desc_p(selector)->access & ACC_PL_U) == ACC_PL_U)
	    return (TRUE);
    }
		
    return (FALSE);
}

extern boolean_t
valid_user_segment_selectors(uint16_t cs,
                             uint16_t ss,
                             uint16_t ds,
                             uint16_t es,
                             uint16_t fs,
                             uint16_t gs);

__END_DECLS

#endif	/* _I386_MP_DESC_H_ */
Commit	Line	Data
1c79356b	1	/*
91447636	2	* Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved.
1c79356b	3	*
8f6c56a5	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
1c79356b	5	*
8f6c56a5 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 License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
	14	*
	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
8ad349bb	24	* limitations under the License.
8f6c56a5 A	25	*
8f6c56a5 A	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
1c79356b A	27	*/
	28	/*
	29	* @OSF_COPYRIGHT@
	30	*/
	31	/*
	32	* Mach Operating System
	33	* Copyright (c) 1991,1990 Carnegie Mellon University
	34	* All Rights Reserved.
	35	*
	36	* Permission to use, copy, modify and distribute this software and its
	37	* documentation is hereby granted, provided that both the copyright
	38	* notice and this permission notice appear in all copies of the
	39	* software, derivative works or modified versions, and any portions
	40	* thereof, and that both notices appear in supporting documentation.
	41	*
	42	* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
	43	* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
	44	* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
	45	*
	46	* Carnegie Mellon requests users of this software to return to
	47	*
	48	* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
	49	* School of Computer Science
	50	* Carnegie Mellon University
	51	* Pittsburgh PA 15213-3890
	52	*
	53	* any improvements or extensions that they make and grant Carnegie Mellon
	54	* the rights to redistribute these changes.
	55	*/
	56
	57	/*
	58	*/
	59
	60	#ifndef _I386_MP_DESC_H_
	61	#define _I386_MP_DESC_H_
	62
1c79356b	63	#include <mach_kdb.h>
91447636 A	64	#include <sys/cdefs.h>
	65
	66	__BEGIN_DECLS
1c79356b A	67
	68	/*
	69	* Multiprocessor i386/i486 systems use a separate copy of the
	70	* GDT, IDT, LDT, and kernel TSS per processor. The first three
	71	* are separate to avoid lock contention: the i386 uses locked
	72	* memory cycles to access the descriptor tables. The TSS is
	73	* separate since each processor needs its own kernel stack,
	74	* and since using a TSS marks it busy.
	75	*/
	76
	77	#include <i386/seg.h>
	78	#include <i386/tss.h>
	79
	80	/*
	81	* The descriptor tables are together in a structure
	82	* allocated one per processor (except for the boot processor).
	83	* Note that dbtss could be conditionalized on MACH_KDB, but
	84	* doing so increases misconfiguration risk.
	85	*/
21362eb3 A	86	struct mp_desc_table {
	87	struct fake_descriptor idt[IDTSZ]; /* IDT */
	88	struct fake_descriptor gdt[GDTSZ]; /* GDT */
	89	struct fake_descriptor ldt[LDTSZ]; /* LDT */
	90	struct i386_tss ktss;
	91	struct i386_tss dbtss;
	92	};
1c79356b	93
91447636 A	94	#define current_gdt() (current_cpu_datap()->cpu_desc_index.cdi_gdt)
	95	#define current_idt() (current_cpu_datap()->cpu_desc_index.cdi_idt)
	96	#define current_ldt() (current_cpu_datap()->cpu_desc_index.cdi_ldt)
	97	#define current_ktss() (current_cpu_datap()->cpu_desc_index.cdi_ktss)
	98	#define current_dbtss() (current_cpu_datap()->cpu_desc_index.cdi_dbtss)
1c79356b	99
91447636 A	100	#define gdt_desc_p(sel) \
	101	((struct real_descriptor *)&current_gdt()[sel_idx(sel)])
	102	#define ldt_desc_p(sel) \
	103	((struct real_descriptor *)&current_ldt()[sel_idx(sel)])
1c79356b	104
21362eb3	105	extern void mp_desc_init(cpu_data_t *cdp, boolean_t is_boot_cpu);
1c79356b	106
91447636 A	107	static inline boolean_t
	108	valid_user_data_selector(uint16_t selector)
	109	{
	110	sel_t sel = selector_to_sel(selector);
	111
	112	if (selector == 0)
	113	return (TRUE);
1c79356b	114
91447636 A	115	if (sel.ti == SEL_LDT)
	116	return (TRUE);
	117	else if (sel.index < GDTSZ) {
	118	if ((gdt_desc_p(selector)->access & ACC_PL_U) == ACC_PL_U)
	119	return (TRUE);
	120	}
	121
	122	return (FALSE);
	123	}
	124
	125	static inline boolean_t
	126	valid_user_code_selector(uint16_t selector)
	127	{
	128	sel_t sel = selector_to_sel(selector);
	129
	130	if (selector == 0)
	131	return (FALSE);
	132
	133	if (sel.ti == SEL_LDT) {
	134	if (sel.rpl == USER_PRIV)
	135	return (TRUE);
	136	}
	137	else if (sel.index < GDTSZ && sel.rpl == USER_PRIV) {
	138	if ((gdt_desc_p(selector)->access & ACC_PL_U) == ACC_PL_U)
	139	return (TRUE);
	140	}
	141
	142	return (FALSE);
	143	}
	144
	145	static inline boolean_t
	146	valid_user_stack_selector(uint16_t selector)
	147	{
	148	sel_t sel = selector_to_sel(selector);
	149
	150	if (selector == 0)
	151	return (FALSE);
	152
	153	if (sel.ti == SEL_LDT) {
	154	if (sel.rpl == USER_PRIV)
	155	return (TRUE);
	156	}
	157	else if (sel.index < GDTSZ && sel.rpl == USER_PRIV) {
	158	if ((gdt_desc_p(selector)->access & ACC_PL_U) == ACC_PL_U)
	159	return (TRUE);
	160	}
	161
	162	return (FALSE);
	163	}
	164
	165	extern boolean_t
	166	valid_user_segment_selectors(uint16_t cs,
	167	uint16_t ss,
	168	uint16_t ds,
	169	uint16_t es,
	170	uint16_t fs,
	171	uint16_t gs);
1c79356b	172
91447636	173	__END_DECLS
1c79356b A	174
1c79356b A	175	#endif /* _I386_MP_DESC_H_ */