1 /*- 2 * Copyright (c) 1988 University of Utah. 3 * Copyright (c) 1982, 1986, 1990 The Regents of the University of California. 4 * All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * the Systems Programming Group of the University of Utah Computer 8 * Science Department, and code derived from software contributed to 9 * Berkeley by William Jolitz. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the University of 22 * California, Berkeley and its contributors. 23 * 4. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * from: Utah $Hdr: mem.c 1.13 89/10/08$ 40 * from: @(#)mem.c 7.2 (Berkeley) 5/9/91 41 * $Id: mem.c,v 1.18 1995/11/04 13:52:30 bde Exp $ 42 */ 43 44 /* 45 * Memory special file 46 */ 47 48 #include <sys/param.h> 49 #include <sys/conf.h> 50 #include <sys/buf.h> 51 #include <sys/systm.h> 52 #include <sys/uio.h> 53 #include <sys/malloc.h> 54 #include <sys/proc.h> 55 56 #include <machine/cpu.h> 57 #include <machine/random.h> 58 #include <machine/psl.h> 59 60 #include <vm/vm.h> 61 #include <vm/vm_param.h> 62 #include <vm/lock.h> 63 #include <vm/vm_prot.h> 64 #include <vm/pmap.h> 65 66 #ifdef DEVFS 67 #include <sys/devfsext.h> 68 #include "sys/kernel.h" 69 70 static void memdev_init __P((void *)); 71 SYSINIT(memdev,SI_SUB_DEVFS, SI_ORDER_ANY, memdev_init, NULL) 72 73 static void 74 memdev_init(dummy) 75 void *dummy; 76 { 77 void * x; 78 /* path name devsw minor type uid gid perm*/ 79 x=dev_add("/misc", "mem", mmopen, 0, DV_CHR, 0, 2, 0640); 80 x=dev_add("/misc", "kmem", mmopen, 1, DV_CHR, 0, 2, 0640); 81 x=dev_add("/misc", "null", mmopen, 2, DV_CHR, 0, 0, 0666); 82 x=dev_add("/misc", "random", mmopen, 3, DV_CHR, 0, 0, 0666); 83 x=dev_add("/misc", "urandom", mmopen, 4, DV_CHR, 0, 0, 0666); 84 x=dev_add("/misc", "zero", mmopen, 12, DV_CHR, 0, 0, 0666); 85 x=dev_add("/misc", "io", mmopen, 14, DV_CHR, 0, 2, 0640); 86 } 87 #endif /* DEVFS */ 88 89 extern char *ptvmmap; /* poor name! */ 90 91 int 92 mmclose(dev, flags, fmt, p) 93 dev_t dev; 94 int flags; 95 int fmt; 96 struct proc *p; 97 { 98 struct trapframe *fp; 99 100 switch (minor(dev)) { 101 case 14: 102 fp = (struct trapframe *)curproc->p_md.md_regs; 103 fp->tf_eflags &= ~PSL_IOPL; 104 break; 105 default: 106 break; 107 } 108 return(0); 109 } 110 111 int 112 mmopen(dev, flags, fmt, p) 113 dev_t dev; 114 int flags; 115 int fmt; 116 struct proc *p; 117 { 118 struct trapframe *fp; 119 120 switch (minor(dev)) { 121 case 14: 122 fp = (struct trapframe *)curproc->p_md.md_regs; 123 fp->tf_eflags |= PSL_IOPL; 124 break; 125 default: 126 break; 127 } 128 return(0); 129 } 130 131 int 132 mmrw(dev, uio, flags) 133 dev_t dev; 134 struct uio *uio; 135 int flags; 136 { 137 register int o; 138 register u_int c, v; 139 u_int poolsize; 140 register struct iovec *iov; 141 int error = 0; 142 caddr_t buf = NULL; 143 144 while (uio->uio_resid > 0 && error == 0) { 145 iov = uio->uio_iov; 146 if (iov->iov_len == 0) { 147 uio->uio_iov++; 148 uio->uio_iovcnt--; 149 if (uio->uio_iovcnt < 0) 150 panic("mmrw"); 151 continue; 152 } 153 switch (minor(dev)) { 154 155 /* minor device 0 is physical memory */ 156 case 0: 157 v = uio->uio_offset; 158 pmap_enter(kernel_pmap, (vm_offset_t)ptvmmap, v, 159 uio->uio_rw == UIO_READ ? VM_PROT_READ : VM_PROT_WRITE, 160 TRUE); 161 o = (int)uio->uio_offset & PGOFSET; 162 c = (u_int)(NBPG - ((int)iov->iov_base & PGOFSET)); 163 c = min(c, (u_int)(NBPG - o)); 164 c = min(c, (u_int)iov->iov_len); 165 error = uiomove((caddr_t)&ptvmmap[o], (int)c, uio); 166 pmap_remove(kernel_pmap, (vm_offset_t)ptvmmap, 167 (vm_offset_t)&ptvmmap[NBPG]); 168 continue; 169 170 /* minor device 1 is kernel memory */ 171 case 1: { 172 vm_offset_t addr, eaddr; 173 c = iov->iov_len; 174 175 /* 176 * Make sure that all of the pages are currently resident so 177 * that we don't create any zero-fill pages. 178 */ 179 addr = trunc_page(uio->uio_offset); 180 eaddr = round_page(uio->uio_offset + c); 181 for (; addr < eaddr; addr += PAGE_SIZE) 182 if (pmap_extract(kernel_pmap, addr) == 0) 183 return EFAULT; 184 185 if (!kernacc((caddr_t)(int)uio->uio_offset, c, 186 uio->uio_rw == UIO_READ ? B_READ : B_WRITE)) 187 return(EFAULT); 188 error = uiomove((caddr_t)(int)uio->uio_offset, (int)c, uio); 189 continue; 190 } 191 192 /* minor device 2 is EOF/RATHOLE */ 193 case 2: 194 if (uio->uio_rw == UIO_READ) 195 return (0); 196 c = iov->iov_len; 197 break; 198 199 /* minor device 3 (/dev/random) is source of filth on read, rathole on write */ 200 case 3: 201 if (uio->uio_rw == UIO_WRITE) { 202 c = iov->iov_len; 203 break; 204 } 205 if (buf == NULL) 206 buf = (caddr_t) 207 malloc(CLBYTES, M_TEMP, M_WAITOK); 208 c = min(iov->iov_len, CLBYTES); 209 poolsize = read_random(buf, c); 210 if (poolsize == 0) { 211 if (buf) 212 free(buf, M_TEMP); 213 return (0); 214 } 215 c = min(c, poolsize); 216 error = uiomove(buf, (int)c, uio); 217 continue; 218 219 /* minor device 4 (/dev/urandom) is source of muck on read, rathole on write */ 220 case 4: 221 if (uio->uio_rw == UIO_WRITE) { 222 c = iov->iov_len; 223 break; 224 } 225 if (buf == NULL) 226 buf = (caddr_t) 227 malloc(CLBYTES, M_TEMP, M_WAITOK); 228 c = min(iov->iov_len, CLBYTES); 229 poolsize = read_random_unlimited(buf, c); 230 c = min(c, poolsize); 231 error = uiomove(buf, (int)c, uio); 232 continue; 233 234 /* minor device 12 (/dev/zero) is source of nulls on read, rathole on write */ 235 case 12: 236 if (uio->uio_rw == UIO_WRITE) { 237 c = iov->iov_len; 238 break; 239 } 240 if (buf == NULL) { 241 buf = (caddr_t) 242 malloc(CLBYTES, M_TEMP, M_WAITOK); 243 bzero(buf, CLBYTES); 244 } 245 c = min(iov->iov_len, CLBYTES); 246 error = uiomove(buf, (int)c, uio); 247 continue; 248 249 #ifdef notyet 250 /* 386 I/O address space (/dev/ioport[bwl]) is a read/write access to seperate 251 i/o device address bus, different than memory bus. Semantics here are 252 very different than ordinary read/write, as if iov_len is a multiple 253 an implied string move from a single port will be done. Note that lseek 254 must be used to set the port number reliably. */ 255 case 14: 256 if (iov->iov_len == 1) { 257 u_char tmp; 258 tmp = inb(uio->uio_offset); 259 error = uiomove (&tmp, iov->iov_len, uio); 260 } else { 261 if (!useracc((caddr_t)iov->iov_base, 262 iov->iov_len, uio->uio_rw)) 263 return (EFAULT); 264 insb(uio->uio_offset, iov->iov_base, 265 iov->iov_len); 266 } 267 break; 268 case 15: 269 if (iov->iov_len == sizeof (short)) { 270 u_short tmp; 271 tmp = inw(uio->uio_offset); 272 error = uiomove (&tmp, iov->iov_len, uio); 273 } else { 274 if (!useracc((caddr_t)iov->iov_base, 275 iov->iov_len, uio->uio_rw)) 276 return (EFAULT); 277 insw(uio->uio_offset, iov->iov_base, 278 iov->iov_len/ sizeof (short)); 279 } 280 break; 281 case 16: 282 if (iov->iov_len == sizeof (long)) { 283 u_long tmp; 284 tmp = inl(uio->uio_offset); 285 error = uiomove (&tmp, iov->iov_len, uio); 286 } else { 287 if (!useracc((caddr_t)iov->iov_base, 288 iov->iov_len, uio->uio_rw)) 289 return (EFAULT); 290 insl(uio->uio_offset, iov->iov_base, 291 iov->iov_len/ sizeof (long)); 292 } 293 break; 294 #endif 295 296 default: 297 return (ENXIO); 298 } 299 if (error) 300 break; 301 iov->iov_base += c; 302 iov->iov_len -= c; 303 uio->uio_offset += c; 304 uio->uio_resid -= c; 305 } 306 if (buf) 307 free(buf, M_TEMP); 308 return (error); 309 } 310 311 312 313 314 /*******************************************************\ 315 * allow user processes to MMAP some memory sections * 316 * instead of going through read/write * 317 \*******************************************************/ 318 int memmmap(dev_t dev, int offset, int nprot) 319 { 320 switch (minor(dev)) 321 { 322 323 /* minor device 0 is physical memory */ 324 case 0: 325 return i386_btop(offset); 326 327 /* minor device 1 is kernel memory */ 328 case 1: 329 return i386_btop(vtophys(offset)); 330 331 default: 332 return -1; 333 } 334 } 335 336 /* 337 * Allow userland to select which interrupts will be used in the muck 338 * gathering business. 339 */ 340 int 341 mmioctl(dev, cmd, cmdarg, flags, p) 342 dev_t dev; 343 int cmd; 344 caddr_t cmdarg; 345 int flags; 346 struct proc *p; 347 { 348 int error; 349 350 if (minor(dev) != 3 && minor(dev) != 4) 351 return (ENODEV); 352 353 if (*(u_int16_t *)cmdarg >= 16) 354 return (EINVAL); 355 356 /* Only root can do this */ 357 error = suser(p->p_ucred, &p->p_acflag); 358 if (error != 0) { 359 return (error); 360 } 361 362 switch (cmd){ 363 364 case MEM_SETIRQ: 365 interrupt_allowed |= 1 << *(u_int16_t *)cmdarg; 366 break; 367 368 case MEM_CLEARIRQ: 369 interrupt_allowed &= ~(1 << *(u_int16_t *)cmdarg); 370 break; 371 372 case MEM_RETURNIRQ: 373 *(u_int16_t *)cmdarg = interrupt_allowed; 374 break; 375 376 default: 377 return (ENOTTY); 378 } 379 return (0); 380 } 381