1 /* 2 * Copyright (c) 2019 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 #ifndef _KERN_RESTARTABLE_H_ 30 #define _KERN_RESTARTABLE_H_ 31 32 #include <sys/cdefs.h> 33 #include <mach/message.h> 34 #include <mach/task.h> 35 36 __BEGIN_DECLS 37 38 /*! 39 * @typedef task_restartable_range_t 40 * 41 * @brief 42 * Describes a userspace recoverable range. 43 * 44 * @field location 45 * The pointer to the beginning of a restartable section. 46 * 47 * @field length 48 * The length of the critical section anchored at location. 49 * 50 * @field recovery_offs 51 * The offset from the initial location that should be used for the recovery 52 * codepath. 53 * 54 * @field flags 55 * Currently unused, pass 0. 56 */ 57 typedef struct { 58 mach_vm_address_t location; 59 unsigned short length; 60 unsigned short recovery_offs; 61 unsigned int flags; 62 } task_restartable_range_t; 63 64 typedef task_restartable_range_t *task_restartable_range_array_t; 65 66 /*! 67 * @function task_restartable_ranges_register 68 * 69 * @brief 70 * Register a set of restartable ranges for the current task. 71 * 72 * @param task 73 * The task to operate on 74 * 75 * @param ranges 76 * An array of address ranges for which PC resets are performed. 77 * 78 * @param count 79 * The number of address ranges. 80 * 81 * @returns 82 * - KERN_SUCCESS on success 83 * - KERN_FAILURE if the task isn't the current one 84 * - KERN_INVALID_ARGUMENT for various invalid inputs 85 * - KERN_NOT_SUPPORTED the request is not supported (second registration on 86 * release kernels, registration when the task has gone wide) 87 * - KERN_RESOURCE_SHORTAGE if not enough memory 88 */ 89 extern kern_return_t task_restartable_ranges_register( 90 task_t task, 91 task_restartable_range_array_t ranges, 92 mach_msg_type_number_t count); 93 94 /*! 95 * @function task_restartable_ranges_synchronize 96 * 97 * @brief 98 * Require for all threads in the task to reset their PC 99 * if within a restartable range. 100 * 101 * @param task 102 * The task to operate on (needs to be current task) 103 * 104 * @returns 105 * - KERN_SUCCESS 106 * - KERN_FAILURE if the task isn't the current one 107 */ 108 extern kern_return_t task_restartable_ranges_synchronize(task_t task); 109 110 /*! 111 * @const TASK_RESTARTABLE_OFFSET_MAX 112 * The maximum value length / recovery_offs can have. 113 */ 114 #define TASK_RESTARTABLE_OFFSET_MAX 4096u 115 116 #ifdef KERNEL_PRIVATE 117 #pragma GCC visibility push(hidden) 118 119 struct restartable_ranges; 120 121 /** 122 * @function restartable_init 123 * 124 * @brief 125 * Initializes the restartable module. 126 */ 127 extern void restartable_init(void); 128 129 /** 130 * @function restartable_ranges_release 131 * 132 * @brief 133 * Release a reference on a restartable range. 134 */ 135 extern void restartable_ranges_release(struct restartable_ranges *ranges); 136 137 /** 138 * @function thread_reset_pcs_in_range 139 * 140 * @brief 141 * Returns whether a non running thread is currently in a critical range. 142 */ 143 extern bool thread_reset_pcs_in_range(task_t task, struct thread *thread); 144 145 /** 146 * @function thread_reset_pcs_will_fault 147 * 148 * @brief 149 * Called by the platform code when about to handle a user fault exception. 150 */ 151 extern void thread_reset_pcs_will_fault(struct thread *thread); 152 153 /** 154 * @function thread_reset_pcs_done_faulting 155 * 156 * @brief 157 * Called by the platform code when being done handling a user fault 158 * exception. 159 */ 160 extern void thread_reset_pcs_done_faulting(struct thread *thread); 161 162 /** 163 * @function thread_reset_pcs_ast 164 * 165 * @brief 166 * Perform the work at the AST boundary to reset thread PCS. 167 */ 168 extern void thread_reset_pcs_ast(task_t task, struct thread *thread); 169 170 /** 171 * @function thread_reset_pcs_ack_IPI 172 * 173 * @brief 174 * Called by the scheduler code when acking the reset-pcs IPI. 175 */ 176 extern void thread_reset_pcs_ack_IPI(struct thread *thread); 177 178 #pragma GCC visibility pop 179 #endif // KERNEL_PRIVATE 180 181 __END_DECLS 182 183 #endif /* _KERN_RESTARTABLE_H_ */ 184