[apple/xnu.git] / osfmk / x86_64 / locore.s

/*
 * Copyright (c) 2000-2007 Apple 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.
 */

#include <mach_rt.h>
#include <platforms.h>
#include <mach_kdp.h>
#include <mach_assert.h>

#include <sys/errno.h>
#include <i386/asm.h>
#include <i386/cpuid.h>
#include <i386/eflags.h>
#include <i386/proc_reg.h>
#include <i386/trap.h>
#include <assym.s>
#include <mach/exception_types.h>
#include <config_dtrace.h>

#define _ARCH_I386_ASM_HELP_H_          /* Prevent inclusion of user header */
#include <mach/i386/syscall_sw.h>

#include <i386/mp.h>

/*
 * Fault recovery.
 */

#ifdef	__MACHO__
#define	RECOVERY_SECTION	.section	__VECTORS, __recover 
#else
#define	RECOVERY_SECTION	.text
#define	RECOVERY_SECTION	.text
#endif

#define	RECOVER_TABLE_START	\
	.align 3		; \
	.globl	EXT(recover_table) ;\
LEXT(recover_table)		;\
	.text

#define	RECOVER(addr)		\
	.align	3;		\
	.quad	9f		;\
	.quad	addr		;\
	.text			;\
9:

#define	RECOVER_TABLE_END		\
	.align	3			;\
	.globl	EXT(recover_table_end)	;\
LEXT(recover_table_end)			;\
	.text

/*
 * Allocate recovery and table.
 */
	RECOVERY_SECTION
	RECOVER_TABLE_START

/*
 * int rdmsr_carefully(uint32_t msr, uint32_t *lo, uint32_t *hi)
 */
ENTRY(rdmsr_carefully)
	movl	%edi, %ecx
	movq	%rdx, %rdi
	RECOVERY_SECTION
	RECOVER(rdmsr_fail)
	rdmsr
	movl	%eax, (%rsi)
	movl	%edx, (%rdi)
	xorl	%eax, %eax
	ret

rdmsr_fail:
	movq	$1, %rax
	ret

.globl	EXT(thread_exception_return)
.globl	EXT(thread_bootstrap_return)
LEXT(thread_bootstrap_return)
#if CONFIG_DTRACE
	call EXT(dtrace_thread_bootstrap)
#endif

LEXT(thread_exception_return)
	cli
	xorl	%ecx, %ecx		/* don't check if we're in the PFZ */
	jmp	EXT(return_from_trap)

/*
 * Copyin/out from user/kernel address space.
 * rdi:	source address
 * rsi:	destination address
 * rdx:	byte count
 */
Entry(_bcopy)
// TODO not pop regs; movq; think about 32 bit or 64 bit byte count
	xchgq	%rdi, %rsi		/* source %rsi, dest %rdi */

	cld				/* count up */
	movl	%edx,%ecx		/* move by longwords first */
	shrl	$3,%ecx
	RECOVERY_SECTION
	RECOVER(_bcopy_fail)
	rep
	movsq				/* move longwords */

	movl	%edx,%ecx		/* now move remaining bytes */
	andl	$7,%ecx
	RECOVERY_SECTION
	RECOVER(_bcopy_fail)
	rep
	movsb

	xorl	%eax,%eax		/* return 0 for success */
	ret				/* and return */

_bcopy_fail:
	movl	$(EFAULT),%eax		/* return error for failure */
	ret

Entry(pmap_safe_read)
	RECOVERY_SECTION
	RECOVER(_pmap_safe_read_fail)
	movq	(%rdi), %rcx
	mov	%rcx, (%rsi)
	mov	$1, %eax
	ret
_pmap_safe_read_fail:
	xor	%eax, %eax
	ret


/*
 * Copyin string from user/kern address space.
 * rdi:	source address
 * rsi:	destination address
 * rdx:	max byte count
 * rcx:	actual byte count (OUT)
 */
Entry(_bcopystr)
	pushq	%rdi
	xchgq	%rdi, %rsi		/* source %rsi, dest %rdi */

	xorl	%eax,%eax		/* set to 0 here so that high 24 bits */
					/* are 0 for the cmpl against 0 */
2:
	RECOVERY_SECTION
	RECOVER(_bcopystr_fail)		/* copy bytes... */
	movb	(%rsi),%al
	incq	%rsi
	testq	%rdi,%rdi		/* if kernel address is ... */
	jz	3f			/* not NULL */
	movb	%al,(%rdi)		/* copy the byte */
	incq	%rdi
3:
	testl	%eax,%eax		/* did we just stuff the 0-byte? */
	jz	4f			/* yes, return 0 already in %eax */
	decq	%rdx			/* decrement #bytes left in buffer */
	jnz	2b			/* buffer not full, copy another byte */
	movl	$(ENAMETOOLONG),%eax	/* buffer full, no \0: ENAMETOOLONG */
4:
	cmpq	$0,%rcx			/* get OUT len ptr */
	jz	_bcopystr_ret		/* if null, just return */
	subq	(%rsp),%rsi
	movq	%rsi,(%rcx)		/* else set OUT arg to xfer len */
	popq	%rdi			/* restore registers */
_bcopystr_ret:
	ret				/* and return */

_bcopystr_fail:
	popq	%rdi			/* restore registers */
	movl	$(EFAULT),%eax		/* return error for failure */
	ret

/*
 * Done with recovery table.
 */
	RECOVERY_SECTION
	RECOVER_TABLE_END
Commit	Line	Data
b0d623f7 A	1	/*
	2	* Copyright (c) 2000-2007 Apple Inc. All rights reserved.
	3	*
	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
	5	*
	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
	24	* limitations under the License.
	25	*
	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
	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	#include <mach_rt.h>
	58	#include <platforms.h>
b0d623f7	59	#include <mach_kdp.h>
b0d623f7 A	60	#include <mach_assert.h>
	61
	62	#include <sys/errno.h>
	63	#include <i386/asm.h>
	64	#include <i386/cpuid.h>
	65	#include <i386/eflags.h>
	66	#include <i386/proc_reg.h>
	67	#include <i386/trap.h>
	68	#include <assym.s>
	69	#include <mach/exception_types.h>
	70	#include <config_dtrace.h>
	71
	72	#define _ARCH_I386_ASM_HELP_H_ /* Prevent inclusion of user header */
	73	#include <mach/i386/syscall_sw.h>
	74
	75	#include <i386/mp.h>
	76
	77	/*
	78	* Fault recovery.
	79	*/
	80
	81	#ifdef __MACHO__
	82	#define RECOVERY_SECTION .section __VECTORS, __recover
	83	#else
	84	#define RECOVERY_SECTION .text
	85	#define RECOVERY_SECTION .text
	86	#endif
	87
	88	#define RECOVER_TABLE_START \
	89	.align 3 ; \
	90	.globl EXT(recover_table) ;\
	91	LEXT(recover_table) ;\
	92	.text
	93
	94	#define RECOVER(addr) \
	95	.align 3; \
	96	.quad 9f ;\
	97	.quad addr ;\
	98	.text ;\
	99	9:
	100
	101	#define RECOVER_TABLE_END \
	102	.align 3 ;\
	103	.globl EXT(recover_table_end) ;\
	104	LEXT(recover_table_end) ;\
	105	.text
	106
	107	/*
	108	* Allocate recovery and table.
	109	*/
	110	RECOVERY_SECTION
	111	RECOVER_TABLE_START
	112
b0d623f7 A	113	/*
	114	* int rdmsr_carefully(uint32_t msr, uint32_t lo, uint32_t hi)
	115	*/
	116	ENTRY(rdmsr_carefully)
	117	movl %edi, %ecx
	118	movq %rdx, %rdi
	119	RECOVERY_SECTION
	120	RECOVER(rdmsr_fail)
	121	rdmsr
	122	movl %eax, (%rsi)
	123	movl %edx, (%rdi)
	124	xorl %eax, %eax
	125	ret
	126
	127	rdmsr_fail:
	128	movq $1, %rax
	129	ret
	130
	131	.globl EXT(thread_exception_return)
	132	.globl EXT(thread_bootstrap_return)
	133	LEXT(thread_bootstrap_return)
	134	#if CONFIG_DTRACE
	135	call EXT(dtrace_thread_bootstrap)
	136	#endif
	137
	138	LEXT(thread_exception_return)
	139	cli
6d2010ae	140	xorl %ecx, %ecx /* don't check if we're in the PFZ */
b0d623f7 A	141	jmp EXT(return_from_trap)
	142
	143	/*
	144	* Copyin/out from user/kernel address space.
	145	* rdi: source address
	146	* rsi: destination address
	147	* rdx: byte count
	148	*/
	149	Entry(_bcopy)
	150	// TODO not pop regs; movq; think about 32 bit or 64 bit byte count
	151	xchgq %rdi, %rsi /* source %rsi, dest %rdi */
	152
	153	cld /* count up */
	154	movl %edx,%ecx /* move by longwords first */
	155	shrl $3,%ecx
	156	RECOVERY_SECTION
	157	RECOVER(_bcopy_fail)
	158	rep
	159	movsq /* move longwords */
	160
	161	movl %edx,%ecx /* now move remaining bytes */
	162	andl $7,%ecx
	163	RECOVERY_SECTION
	164	RECOVER(_bcopy_fail)
	165	rep
	166	movsb
	167
	168	xorl %eax,%eax /* return 0 for success */
	169	ret /* and return */
	170
	171	_bcopy_fail:
	172	movl $(EFAULT),%eax /* return error for failure */
	173	ret
	174
6d2010ae A	175	Entry(pmap_safe_read)
	176	RECOVERY_SECTION
	177	RECOVER(_pmap_safe_read_fail)
	178	movq (%rdi), %rcx
	179	mov %rcx, (%rsi)
	180	mov $1, %eax
	181	ret
	182	_pmap_safe_read_fail:
	183	xor %eax, %eax
	184	ret
	185
b0d623f7 A	186
	187
	188	/*
	189	* Copyin string from user/kern address space.
	190	* rdi: source address
	191	* rsi: destination address
	192	* rdx: max byte count
	193	* rcx: actual byte count (OUT)
	194	*/
	195	Entry(_bcopystr)
	196	pushq %rdi
	197	xchgq %rdi, %rsi /* source %rsi, dest %rdi */
	198
	199	xorl %eax,%eax /* set to 0 here so that high 24 bits */
	200	/* are 0 for the cmpl against 0 */
	201	2:
	202	RECOVERY_SECTION
	203	RECOVER(_bcopystr_fail) /* copy bytes... */
	204	movb (%rsi),%al
	205	incq %rsi
	206	testq %rdi,%rdi /* if kernel address is ... */
	207	jz 3f /* not NULL */
	208	movb %al,(%rdi) /* copy the byte */
	209	incq %rdi
	210	3:
	211	testl %eax,%eax /* did we just stuff the 0-byte? */
	212	jz 4f /* yes, return 0 already in %eax */
	213	decq %rdx /* decrement #bytes left in buffer */
	214	jnz 2b /* buffer not full, copy another byte */
	215	movl $(ENAMETOOLONG),%eax /* buffer full, no \0: ENAMETOOLONG */
	216	4:
	217	cmpq $0,%rcx /* get OUT len ptr */
	218	jz _bcopystr_ret /* if null, just return */
	219	subq (%rsp),%rsi
	220	movq %rsi,(%rcx) /* else set OUT arg to xfer len */
	221	popq %rdi /* restore registers */
	222	_bcopystr_ret:
	223	ret /* and return */
	224
	225	_bcopystr_fail:
	226	popq %rdi /* restore registers */
	227	movl $(EFAULT),%eax /* return error for failure */
	228	ret
	229
b0d623f7 A	230	/*
	231	* Done with recovery table.
	232	*/
	233	RECOVERY_SECTION
	234	RECOVER_TABLE_END
	235