/* * Copyright (c) 2014 Apple Inc. All rights reserved. * * @APPLE_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. 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_HEADER_END@ */ #include <stdint.h> #include <machine/cpu_capabilities.h> #include <sys/kdebug.h> #include <sys/errno.h> #define CLASS_MASK 0xff000000 #define CLASS_OFFSET 24 #define SUBCLASS_MASK 0x00ff0000 #define SUBCLASS_OFFSET 16 #define EXTRACT_CLASS(debugid) ((uint8_t)(((debugid) & CLASS_MASK) >> CLASS_OFFSET)) #define EXTRACT_SUBCLASS(debugid) ( (uint8_t) ( ((debugid) & SUBCLASS_MASK) >> SUBCLASS_OFFSET ) ) extern int __kdebug_trace64(uint32_t code, uint64_t arg1, uint64_t arg2, uint64_t arg3, uint64_t arg4); int kdebug_trace(uint32_t code, uint64_t arg1, uint64_t arg2, uint64_t arg3, uint64_t arg4) { uint8_t code_class; volatile uint32_t *kdebug_enable_address = (volatile uint32_t *)(uintptr_t)(_COMM_PAGE_KDEBUG_ENABLE); /* * This filtering is also done in the kernel, but we also do it here so that errors * are returned in all cases, not just when the system call is actually performed. */ code_class = EXTRACT_CLASS(code); switch (code_class) { case DBG_TRACE: errno = EPERM; return -1; } if (*kdebug_enable_address == 0) { return 0; } return __kdebug_trace64(code, arg1, arg2, arg3, arg4); }