1/* 2 * Copyright (c) 2000-2004 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 * Copyright (c) 1988 University of Utah. 30 * Copyright (c) 1982, 1986, 1990, 1993 31 * The Regents of the University of California. All rights reserved. 32 * 33 * This code is derived from software contributed to Berkeley by 34 * the Systems Programming Group of the University of Utah Computer 35 * Science Department, and code derived from software contributed to 36 * Berkeley by William Jolitz. 37 * 38 * Redistribution and use in source and binary forms, with or without 39 * modification, are permitted provided that the following conditions 40 * are met: 41 * 1. Redistributions of source code must retain the above copyright 42 * notice, this list of conditions and the following disclaimer. 43 * 2. Redistributions in binary form must reproduce the above copyright 44 * notice, this list of conditions and the following disclaimer in the 45 * documentation and/or other materials provided with the distribution. 46 * 3. All advertising materials mentioning features or use of this software 47 * must display the following acknowledgement: 48 * This product includes software developed by the University of 49 * California, Berkeley and its contributors. 50 * 4. Neither the name of the University nor the names of its contributors 51 * may be used to endorse or promote products derived from this software 52 * without specific prior written permission. 53 * 54 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 55 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 56 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 57 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 58 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 59 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 60 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 61 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 62 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 63 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 64 * SUCH DAMAGE. 65 * 66 * from: Utah $Hdr: mem.c 1.13 89/10/08$ 67 * @(#)mem.c 8.1 (Berkeley) 6/11/93 68 */ 69 70#include <mach_load.h> 71 72/* 73 * Memory special file 74 */ 75 76#include <sys/param.h> 77#include <sys/dir.h> 78#include <sys/proc.h> 79#include <sys/systm.h> 80#include <sys/conf.h> 81#include <sys/vm.h> 82#include <sys/uio_internal.h> 83#include <sys/malloc.h> 84 85#include <mach/vm_types.h> 86#include <mach/vm_param.h> 87#include <vm/vm_kern.h> /* for kernel_map */ 88 89extern addr64_t kvtophys(vm_offset_t va); 90extern boolean_t kernacc(off_t, size_t); 91#if !defined(SECURE_KERNEL) 92extern int setup_kmem; 93#endif 94 95static caddr_t devzerobuf; 96 97int mmread(dev_t dev, struct uio *uio); 98int mmwrite(dev_t dev, struct uio *uio); 99int mmioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p); 100int mmrw(dev_t dev, struct uio *uio, enum uio_rw rw); 101 102int mmread(dev_t dev, struct uio *uio) 103{ 104 105 return (mmrw(dev, uio, UIO_READ)); 106} 107 108int mmwrite(dev_t dev, struct uio *uio) 109{ 110 111 return (mmrw(dev, uio, UIO_WRITE)); 112} 113 114int mmioctl(dev_t dev, u_long cmd, __unused caddr_t data, __unused int flag, __unused struct proc *p) 115{ 116 int minnum = minor(dev); 117 118 if (0 == minnum || 1 == minnum) { 119 /* 120 * /dev/mem and /dev/kmem 121 */ 122#if defined(SECURE_KERNEL) 123 return (ENODEV); 124#else 125 if (0 == setup_kmem) 126 return (EINVAL); 127#endif 128 } 129 130 switch (cmd) { 131 case FIONBIO: 132 case FIOASYNC: 133 /* 134 * OK to do nothing: we always return immediately 135 */ 136 break; 137 default: 138 return ENODEV; 139 } 140 141 return (0); 142} 143 144int mmrw(dev_t dev, struct uio *uio, enum uio_rw rw) 145{ 146 register int o; 147 register u_int c, v; 148 int error = 0; 149 vm_offset_t where; 150 vm_size_t size; 151 152 while (uio_resid(uio) > 0 && error == 0) { 153 uio_update(uio, 0); 154 155 switch (minor(dev)) { 156 157 /* 158 * minor device 0 is physical memory 159 */ 160 case 0: 161#if defined(SECURE_KERNEL) 162 return (ENODEV); 163#else 164 if (setup_kmem == 0) 165 return (ENODEV); 166#endif 167 168 v = trunc_page(uio->uio_offset); 169 if (uio->uio_offset >= (off_t) mem_size) 170 goto fault; 171 172 size = PAGE_SIZE; 173 if (kmem_alloc(kernel_map, &where, size) 174 != KERN_SUCCESS) { 175 goto fault; 176 } 177 o = uio->uio_offset - v; 178 c = min(PAGE_SIZE - o, uio_curriovlen(uio)); 179 error = uiomove((caddr_t) (where + o), c, uio); 180 kmem_free(kernel_map, where, PAGE_SIZE); 181 continue; 182 183 /* 184 * minor device 1 is kernel memory 185 */ 186 case 1: 187#if defined(SECURE_KERNEL) 188 return (ENODEV); 189#else 190 if (setup_kmem == 0) 191 return (ENODEV); 192#endif 193 /* 194 * Do some sanity checking 195 */ 196 if (((vm_address_t) uio->uio_offset >= VM_MAX_KERNEL_ADDRESS) || ((vm_address_t) uio->uio_offset <= VM_MIN_KERNEL_AND_KEXT_ADDRESS)) 197 goto fault; 198 c = uio_curriovlen(uio); 199 if (!kernacc(uio->uio_offset, c)) 200 goto fault; 201 error = uiomove((caddr_t) (uintptr_t) uio->uio_offset, (int) c, uio); 202 continue; 203 204 /* 205 * minor device 2 is EOF/RATHOLE 206 */ 207 case 2: 208 if (rw == UIO_READ) 209 return (0); 210 c = uio_curriovlen(uio); 211 break; 212 case 3: 213 if (devzerobuf == NULL) { 214 MALLOC(devzerobuf, caddr_t, PAGE_SIZE, M_TEMP, M_WAITOK); 215 bzero(devzerobuf, PAGE_SIZE); 216 } 217 if (uio->uio_rw == UIO_WRITE) { 218 c = uio_curriovlen(uio); 219 break; 220 } 221 c = min(uio_curriovlen(uio), PAGE_SIZE); 222 error = uiomove(devzerobuf, (int) c, uio); 223 continue; 224 default: 225 goto fault; 226 break; 227 } 228 229 if (error) 230 break; 231 uio_update(uio, c); 232 } 233 return (error); 234 fault: 235 return (EFAULT); 236} 237 238boolean_t kernacc(off_t start, size_t len) 239{ 240 off_t base; 241 off_t end; 242 243 base = trunc_page(start); 244 end = start + len; 245 246 while (base < end) { 247 if (kvtophys((vm_offset_t) base) == 0ULL) 248 return (FALSE); 249 base += page_size; 250 } 251 252 return (TRUE); 253} 254