1/* 2 * Copyright (c) 2000-2006 Apple Computer, 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 */ 58 59 60#include <i386/asm.h> 61#include <i386/proc_reg.h> 62#include <i386/mp.h> 63#include <assym.s> 64 65Entry(Load_context) 66 movq TH_KERNEL_STACK(%rdi),%rcx /* get kernel stack */ 67 leaq -IKS_SIZE(%rcx),%rdx 68 addq EXT(kernel_stack_size)(%rip),%rdx /* point to stack top */ 69 movq %rcx,%gs:CPU_ACTIVE_STACK /* store stack address */ 70 movq %rdx,%gs:CPU_KERNEL_STACK /* store stack top */ 71 72 movq %rdx,%rsp 73 movq %rdx,%rbp 74 75 xorq %rdi,%rdi /* return zero (no old thread) */ 76 call EXT(thread_continue) 77 78 79/* 80 * thread_t Switch_context( 81 * thread_t old, // %rsi 82 * thread_continue_t continuation, // %rdi 83 * thread_t new) // %rdx 84 */ 85Entry(Switch_context) 86 popq %rax /* pop return PC */ 87 88 /* Test for a continuation and skip all state saving if so... */ 89 cmpq $0, %rsi 90 jne 5f 91 movq %gs:CPU_KERNEL_STACK,%rcx /* get old kernel stack top */ 92 movq %rbx,KSS_RBX(%rcx) /* save registers */ 93 movq %rbp,KSS_RBP(%rcx) 94 movq %r12,KSS_R12(%rcx) 95 movq %r13,KSS_R13(%rcx) 96 movq %r14,KSS_R14(%rcx) 97 movq %r15,KSS_R15(%rcx) 98 movq %rax,KSS_RIP(%rcx) /* save return PC */ 99 movq %rsp,KSS_RSP(%rcx) /* save SP */ 1005: 101 movq %rdi,%rax /* return old thread */ 102 /* new thread in %rdx */ 103 movq %rdx,%gs:CPU_ACTIVE_THREAD /* new thread is active */ 104 movq TH_KERNEL_STACK(%rdx),%rdx /* get its kernel stack */ 105 lea -IKS_SIZE(%rdx),%rcx 106 add EXT(kernel_stack_size)(%rip),%rcx /* point to stack top */ 107 108 movq %rdx,%gs:CPU_ACTIVE_STACK /* set current stack */ 109 movq %rcx,%gs:CPU_KERNEL_STACK /* set stack top */ 110 111 movq KSS_RSP(%rcx),%rsp /* switch stacks */ 112 movq KSS_RBX(%rcx),%rbx /* restore registers */ 113 movq KSS_RBP(%rcx),%rbp 114 movq KSS_R12(%rcx),%r12 115 movq KSS_R13(%rcx),%r13 116 movq KSS_R14(%rcx),%r14 117 movq KSS_R15(%rcx),%r15 118 jmp *KSS_RIP(%rcx) /* return old thread */ 119 120 121Entry(Thread_continue) 122 movq %rax, %rdi /* load thread argument */ 123 xorq %rbp,%rbp /* zero frame pointer */ 124 call *%rbx /* call real continuation */ 125 126 127/* 128 * thread_t Shutdown_context( 129 * thread_t thread, // %rdi 130 * void (*routine)(processor_t), // %rsi 131 * processor_t processor) // %rdx 132 * 133 * saves the kernel context of the thread, 134 * switches to the interrupt stack, 135 * continues the thread (with thread_continue), 136 * then runs routine on the interrupt stack. 137 * 138 */ 139Entry(Shutdown_context) 140 movq %gs:CPU_KERNEL_STACK,%rcx /* get old kernel stack top */ 141 movq %rbx,KSS_RBX(%rcx) /* save registers */ 142 movq %rbp,KSS_RBP(%rcx) 143 movq %r12,KSS_R12(%rcx) 144 movq %r13,KSS_R13(%rcx) 145 movq %r14,KSS_R14(%rcx) 146 movq %r15,KSS_R15(%rcx) 147 popq KSS_RIP(%rcx) /* save return PC */ 148 movq %rsp,KSS_RSP(%rcx) /* save SP */ 149 150 movq %gs:CPU_ACTIVE_STACK,%rcx /* get old kernel stack */ 151 movq %rdi,%rax /* get old thread */ 152 movq %rcx,TH_KERNEL_STACK(%rax) /* save old stack */ 153 154 movq %gs:CPU_INT_STACK_TOP,%rsp /* switch to interrupt stack */ 155 156 movq %rdx,%rdi /* processor arg to routine */ 157 call *%rsi /* call routine to run */ 158 hlt /* (should never return) */ 159 160