syscall_emul.cc revision 3114:7a4771b9b720
1/* 2 * Copyright (c) 2003-2005 The Regents of The University of Michigan 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are 7 * met: redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer; 9 * redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution; 12 * neither the name of the copyright holders nor the names of its 13 * contributors may be used to endorse or promote products derived from 14 * this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 * 28 * Authors: Steve Reinhardt 29 * Ali Saidi 30 */ 31 32#include <fcntl.h> 33#include <unistd.h> 34 35#include <string> 36#include <iostream> 37 38#include "sim/syscall_emul.hh" 39#include "base/chunk_generator.hh" 40#include "base/trace.hh" 41#include "cpu/thread_context.hh" 42#include "cpu/base.hh" 43#include "mem/page_table.hh" 44#include "sim/process.hh" 45 46#include "sim/sim_exit.hh" 47 48using namespace std; 49using namespace TheISA; 50 51void 52SyscallDesc::doSyscall(int callnum, LiveProcess *process, ThreadContext *tc) 53{ 54 DPRINTFR(SyscallVerbose, "%d: %s: syscall %s called w/arguments %d,%d,%d,%d\n", 55 curTick,tc->getCpuPtr()->name(), name, 56 tc->getSyscallArg(0),tc->getSyscallArg(1), 57 tc->getSyscallArg(2),tc->getSyscallArg(3)); 58 59 SyscallReturn retval = (*funcPtr)(this, callnum, process, tc); 60 61 DPRINTFR(SyscallVerbose, "%d: %s: syscall %s returns %d\n", 62 curTick,tc->getCpuPtr()->name(), name, retval.value()); 63 64 if (!(flags & SyscallDesc::SuppressReturnValue)) 65 tc->setSyscallReturn(retval); 66} 67 68 69SyscallReturn 70unimplementedFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 71 ThreadContext *tc) 72{ 73 fatal("syscall %s (#%d) unimplemented.", desc->name, callnum); 74 75 return 1; 76} 77 78 79SyscallReturn 80ignoreFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 81 ThreadContext *tc) 82{ 83 warn("ignoring syscall %s(%d, %d, ...)", desc->name, 84 tc->getSyscallArg(0), tc->getSyscallArg(1)); 85 86 return 0; 87} 88 89 90SyscallReturn 91exitFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 92 ThreadContext *tc) 93{ 94 if (tc->exit()) { 95 exitSimLoop("target called exit()", tc->getSyscallArg(0) & 0xff); 96 } 97 98 return 1; 99} 100 101 102SyscallReturn 103getpagesizeFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 104{ 105 return (int)VMPageSize; 106} 107 108 109SyscallReturn 110obreakFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 111{ 112 Addr junk; 113 114 // change brk addr to first arg 115 Addr new_brk = tc->getSyscallArg(0); 116 if (new_brk != 0) { 117 for (ChunkGenerator gen(p->brk_point, new_brk - p->brk_point, 118 VMPageSize); !gen.done(); gen.next()) { 119 if (!p->pTable->translate(gen.addr(), junk)) 120 p->pTable->allocate(roundDown(gen.addr(), VMPageSize), 121 VMPageSize); 122 } 123 p->brk_point = new_brk; 124 } 125 DPRINTF(SyscallVerbose, "Break Point changed to: %#X\n", p->brk_point); 126 return p->brk_point; 127} 128 129 130SyscallReturn 131closeFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 132{ 133 int target_fd = tc->getSyscallArg(0); 134 int status = close(p->sim_fd(target_fd)); 135 if (status >= 0) 136 p->free_fd(target_fd); 137 return status; 138} 139 140 141SyscallReturn 142readFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 143{ 144 int fd = p->sim_fd(tc->getSyscallArg(0)); 145 int nbytes = tc->getSyscallArg(2); 146 BufferArg bufArg(tc->getSyscallArg(1), nbytes); 147 148 int bytes_read = read(fd, bufArg.bufferPtr(), nbytes); 149 150 if (bytes_read != -1) 151 bufArg.copyOut(tc->getMemPort()); 152 153 return bytes_read; 154} 155 156SyscallReturn 157writeFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 158{ 159 int fd = p->sim_fd(tc->getSyscallArg(0)); 160 int nbytes = tc->getSyscallArg(2); 161 BufferArg bufArg(tc->getSyscallArg(1), nbytes); 162 163 bufArg.copyIn(tc->getMemPort()); 164 165 int bytes_written = write(fd, bufArg.bufferPtr(), nbytes); 166 167 fsync(fd); 168 169 return bytes_written; 170} 171 172 173SyscallReturn 174lseekFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 175{ 176 int fd = p->sim_fd(tc->getSyscallArg(0)); 177 uint64_t offs = tc->getSyscallArg(1); 178 int whence = tc->getSyscallArg(2); 179 180 off_t result = lseek(fd, offs, whence); 181 182 return (result == (off_t)-1) ? -errno : result; 183} 184 185 186SyscallReturn 187munmapFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 188{ 189 // given that we don't really implement mmap, munmap is really easy 190 return 0; 191} 192 193 194const char *hostname = "m5.eecs.umich.edu"; 195 196SyscallReturn 197gethostnameFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 198{ 199 int name_len = tc->getSyscallArg(1); 200 BufferArg name(tc->getSyscallArg(0), name_len); 201 202 strncpy((char *)name.bufferPtr(), hostname, name_len); 203 204 name.copyOut(tc->getMemPort()); 205 206 return 0; 207} 208 209SyscallReturn 210unlinkFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 211{ 212 string path; 213 214 if (!tc->getMemPort()->tryReadString(path, tc->getSyscallArg(0))) 215 return (TheISA::IntReg)-EFAULT; 216 217 int result = unlink(path.c_str()); 218 return (result == -1) ? -errno : result; 219} 220 221SyscallReturn 222renameFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 223{ 224 string old_name; 225 226 if (!tc->getMemPort()->tryReadString(old_name, tc->getSyscallArg(0))) 227 return -EFAULT; 228 229 string new_name; 230 231 if (!tc->getMemPort()->tryReadString(new_name, tc->getSyscallArg(1))) 232 return -EFAULT; 233 234 int64_t result = rename(old_name.c_str(), new_name.c_str()); 235 return (result == -1) ? -errno : result; 236} 237 238SyscallReturn 239truncateFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 240{ 241 string path; 242 243 if (!tc->getMemPort()->tryReadString(path, tc->getSyscallArg(0))) 244 return -EFAULT; 245 246 off_t length = tc->getSyscallArg(1); 247 248 int result = truncate(path.c_str(), length); 249 return (result == -1) ? -errno : result; 250} 251 252SyscallReturn 253ftruncateFunc(SyscallDesc *desc, int num, LiveProcess *process, ThreadContext *tc) 254{ 255 int fd = process->sim_fd(tc->getSyscallArg(0)); 256 257 if (fd < 0) 258 return -EBADF; 259 260 off_t length = tc->getSyscallArg(1); 261 262 int result = ftruncate(fd, length); 263 return (result == -1) ? -errno : result; 264} 265 266SyscallReturn 267chownFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 268{ 269 string path; 270 271 if (!tc->getMemPort()->tryReadString(path, tc->getSyscallArg(0))) 272 return -EFAULT; 273 274 /* XXX endianess */ 275 uint32_t owner = tc->getSyscallArg(1); 276 uid_t hostOwner = owner; 277 uint32_t group = tc->getSyscallArg(2); 278 gid_t hostGroup = group; 279 280 int result = chown(path.c_str(), hostOwner, hostGroup); 281 return (result == -1) ? -errno : result; 282} 283 284SyscallReturn 285fchownFunc(SyscallDesc *desc, int num, LiveProcess *process, ThreadContext *tc) 286{ 287 int fd = process->sim_fd(tc->getSyscallArg(0)); 288 289 if (fd < 0) 290 return -EBADF; 291 292 /* XXX endianess */ 293 uint32_t owner = tc->getSyscallArg(1); 294 uid_t hostOwner = owner; 295 uint32_t group = tc->getSyscallArg(2); 296 gid_t hostGroup = group; 297 298 int result = fchown(fd, hostOwner, hostGroup); 299 return (result == -1) ? -errno : result; 300} 301 302 303SyscallReturn 304dupFunc(SyscallDesc *desc, int num, LiveProcess *process, ThreadContext *tc) 305{ 306 int fd = process->sim_fd(tc->getSyscallArg(0)); 307 308 if (fd < 0) 309 return -EBADF; 310 311 int result = dup(fd); 312 return (result == -1) ? -errno : process->alloc_fd(result); 313} 314 315 316SyscallReturn 317fcntlFunc(SyscallDesc *desc, int num, LiveProcess *process, 318 ThreadContext *tc) 319{ 320 int fd = tc->getSyscallArg(0); 321 322 if (fd < 0 || process->sim_fd(fd) < 0) 323 return -EBADF; 324 325 int cmd = tc->getSyscallArg(1); 326 switch (cmd) { 327 case 0: // F_DUPFD 328 // if we really wanted to support this, we'd need to do it 329 // in the target fd space. 330 warn("fcntl(%d, F_DUPFD) not supported, error returned\n", fd); 331 return -EMFILE; 332 333 case 1: // F_GETFD (get close-on-exec flag) 334 case 2: // F_SETFD (set close-on-exec flag) 335 return 0; 336 337 case 3: // F_GETFL (get file flags) 338 case 4: // F_SETFL (set file flags) 339 // not sure if this is totally valid, but we'll pass it through 340 // to the underlying OS 341 warn("fcntl(%d, %d) passed through to host\n", fd, cmd); 342 return fcntl(process->sim_fd(fd), cmd); 343 // return 0; 344 345 case 7: // F_GETLK (get lock) 346 case 8: // F_SETLK (set lock) 347 case 9: // F_SETLKW (set lock and wait) 348 // don't mess with file locking... just act like it's OK 349 warn("File lock call (fcntl(%d, %d)) ignored.\n", fd, cmd); 350 return 0; 351 352 default: 353 warn("Unknown fcntl command %d\n", cmd); 354 return 0; 355 } 356} 357 358SyscallReturn 359fcntl64Func(SyscallDesc *desc, int num, LiveProcess *process, 360 ThreadContext *tc) 361{ 362 int fd = tc->getSyscallArg(0); 363 364 if (fd < 0 || process->sim_fd(fd) < 0) 365 return -EBADF; 366 367 int cmd = tc->getSyscallArg(1); 368 switch (cmd) { 369 case 33: //F_GETLK64 370 warn("fcntl64(%d, F_GETLK64) not supported, error returned\n", fd); 371 return -EMFILE; 372 373 case 34: // F_SETLK64 374 case 35: // F_SETLKW64 375 warn("fcntl64(%d, F_SETLK(W)64) not supported, error returned\n", fd); 376 return -EMFILE; 377 378 default: 379 // not sure if this is totally valid, but we'll pass it through 380 // to the underlying OS 381 warn("fcntl64(%d, %d) passed through to host\n", fd, cmd); 382 return fcntl(process->sim_fd(fd), cmd); 383 // return 0; 384 } 385} 386 387SyscallReturn 388pipePseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 389 ThreadContext *tc) 390{ 391 int fds[2], sim_fds[2]; 392 int pipe_retval = pipe(fds); 393 394 if (pipe_retval < 0) { 395 // error 396 return pipe_retval; 397 } 398 399 sim_fds[0] = process->alloc_fd(fds[0]); 400 sim_fds[1] = process->alloc_fd(fds[1]); 401 402 // Alpha Linux convention for pipe() is that fd[0] is returned as 403 // the return value of the function, and fd[1] is returned in r20. 404 tc->setIntReg(SyscallPseudoReturnReg, sim_fds[1]); 405 return sim_fds[0]; 406} 407 408 409SyscallReturn 410getpidPseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 411 ThreadContext *tc) 412{ 413 // Make up a PID. There's no interprocess communication in 414 // fake_syscall mode, so there's no way for a process to know it's 415 // not getting a unique value. 416 417 tc->setIntReg(SyscallPseudoReturnReg, process->ppid()); 418 return process->pid(); 419} 420 421 422SyscallReturn 423getuidPseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 424 ThreadContext *tc) 425{ 426 // Make up a UID and EUID... it shouldn't matter, and we want the 427 // simulation to be deterministic. 428 429 // EUID goes in r20. 430 tc->setIntReg(SyscallPseudoReturnReg, process->euid()); //EUID 431 return process->uid(); // UID 432} 433 434 435SyscallReturn 436getgidPseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 437 ThreadContext *tc) 438{ 439 // Get current group ID. EGID goes in r20. 440 tc->setIntReg(SyscallPseudoReturnReg, process->egid()); //EGID 441 return process->gid(); 442} 443 444 445SyscallReturn 446setuidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 447 ThreadContext *tc) 448{ 449 // can't fathom why a benchmark would call this. 450 warn("Ignoring call to setuid(%d)\n", tc->getSyscallArg(0)); 451 return 0; 452} 453 454SyscallReturn 455getpidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 456 ThreadContext *tc) 457{ 458 // Make up a PID. There's no interprocess communication in 459 // fake_syscall mode, so there's no way for a process to know it's 460 // not getting a unique value. 461 462 tc->setIntReg(SyscallPseudoReturnReg, process->ppid()); //PID 463 return process->pid(); 464} 465 466SyscallReturn 467getppidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 468 ThreadContext *tc) 469{ 470 return process->ppid(); 471} 472 473SyscallReturn 474getuidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 475 ThreadContext *tc) 476{ 477 return process->uid(); // UID 478} 479 480SyscallReturn 481geteuidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 482 ThreadContext *tc) 483{ 484 return process->euid(); // UID 485} 486 487SyscallReturn 488getgidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 489 ThreadContext *tc) 490{ 491 return process->gid(); 492} 493 494SyscallReturn 495getegidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 496 ThreadContext *tc) 497{ 498 return process->egid(); 499} 500 501 502