syscall_emul.cc revision 10955:9abf6a7c14ab
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 <cstdio> 36#include <iostream> 37#include <string> 38 39#include "arch/utility.hh" 40#include "base/chunk_generator.hh" 41#include "base/trace.hh" 42#include "config/the_isa.hh" 43#include "cpu/base.hh" 44#include "cpu/thread_context.hh" 45#include "debug/SyscallVerbose.hh" 46#include "mem/page_table.hh" 47#include "sim/process.hh" 48#include "sim/sim_exit.hh" 49#include "sim/syscall_emul.hh" 50#include "sim/system.hh" 51 52using namespace std; 53using namespace TheISA; 54 55void 56SyscallDesc::doSyscall(int callnum, LiveProcess *process, ThreadContext *tc) 57{ 58 if (DTRACE(SyscallVerbose)) { 59 int index = 0; 60 IntReg arg[4] M5_VAR_USED; 61 62 // we can't just put the calls to getSyscallArg() in the 63 // DPRINTF arg list, because C++ doesn't guarantee their order 64 for (int i = 0; i < 4; ++i) 65 arg[i] = process->getSyscallArg(tc, index); 66 67 DPRINTFNR("%d: %s: syscall %s called w/arguments %d,%d,%d,%d\n", 68 curTick(), tc->getCpuPtr()->name(), name, 69 arg[0], arg[1], arg[2], arg[3]); 70 } 71 72 SyscallReturn retval = (*funcPtr)(this, callnum, process, tc); 73 74 if (retval.needsRetry()) { 75 DPRINTFS(SyscallVerbose, tc->getCpuPtr(), "syscall %s needs retry\n", 76 name); 77 } else { 78 DPRINTFS(SyscallVerbose, tc->getCpuPtr(), "syscall %s returns %d\n", 79 name, retval.encodedValue()); 80 } 81 82 if (!(flags & SyscallDesc::SuppressReturnValue) && !retval.needsRetry()) 83 process->setSyscallReturn(tc, retval); 84} 85 86 87SyscallReturn 88unimplementedFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 89 ThreadContext *tc) 90{ 91 fatal("syscall %s (#%d) unimplemented.", desc->name, callnum); 92 93 return 1; 94} 95 96 97SyscallReturn 98ignoreFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 99 ThreadContext *tc) 100{ 101 int index = 0; 102 const char *extra_text = ""; 103 104 if (desc->warnOnce()) { 105 if (desc->warned) 106 return 0; 107 108 desc->warned = true; 109 extra_text = "\n (further warnings will be suppressed)"; 110 } 111 112 warn("ignoring syscall %s(%d, ...)%s", desc->name, 113 process->getSyscallArg(tc, index), extra_text); 114 115 return 0; 116} 117 118 119SyscallReturn 120exitFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 121 ThreadContext *tc) 122{ 123 if (process->system->numRunningContexts() == 1) { 124 // Last running context... exit simulator 125 int index = 0; 126 exitSimLoop("target called exit()", 127 process->getSyscallArg(tc, index) & 0xff); 128 } else { 129 // other running threads... just halt this one 130 tc->halt(); 131 } 132 133 return 1; 134} 135 136 137SyscallReturn 138exitGroupFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 139 ThreadContext *tc) 140{ 141 // halt all threads belonging to this process 142 for (auto i: process->contextIds) { 143 process->system->getThreadContext(i)->halt(); 144 } 145 146 if (!process->system->numRunningContexts()) { 147 // all threads belonged to this process... exit simulator 148 int index = 0; 149 exitSimLoop("target called exit()", 150 process->getSyscallArg(tc, index) & 0xff); 151 } 152 153 return 1; 154} 155 156 157SyscallReturn 158getpagesizeFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 159{ 160 return (int)PageBytes; 161} 162 163 164SyscallReturn 165brkFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 166{ 167 // change brk addr to first arg 168 int index = 0; 169 Addr new_brk = p->getSyscallArg(tc, index); 170 171 // in Linux at least, brk(0) returns the current break value 172 // (note that the syscall and the glibc function have different behavior) 173 if (new_brk == 0) 174 return p->brk_point; 175 176 if (new_brk > p->brk_point) { 177 // might need to allocate some new pages 178 for (ChunkGenerator gen(p->brk_point, new_brk - p->brk_point, 179 PageBytes); !gen.done(); gen.next()) { 180 if (!p->pTable->translate(gen.addr())) 181 p->allocateMem(roundDown(gen.addr(), PageBytes), PageBytes); 182 183 // if the address is already there, zero it out 184 else { 185 uint8_t zero = 0; 186 SETranslatingPortProxy &tp = tc->getMemProxy(); 187 188 // split non-page aligned accesses 189 Addr next_page = roundUp(gen.addr(), PageBytes); 190 uint32_t size_needed = next_page - gen.addr(); 191 tp.memsetBlob(gen.addr(), zero, size_needed); 192 if (gen.addr() + PageBytes > next_page && 193 next_page < new_brk && 194 p->pTable->translate(next_page)) 195 { 196 size_needed = PageBytes - size_needed; 197 tp.memsetBlob(next_page, zero, size_needed); 198 } 199 } 200 } 201 } 202 203 p->brk_point = new_brk; 204 DPRINTF(SyscallVerbose, "Break Point changed to: %#X\n", p->brk_point); 205 return p->brk_point; 206} 207 208 209SyscallReturn 210closeFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 211{ 212 int index = 0; 213 int tgt_fd = p->getSyscallArg(tc, index); 214 215 int sim_fd = p->getSimFD(tgt_fd); 216 if (sim_fd < 0) 217 return -EBADF; 218 219 int status = 0; 220 if (sim_fd > 2) 221 status = close(sim_fd); 222 if (status >= 0) 223 p->resetFDEntry(tgt_fd); 224 return status; 225} 226 227 228SyscallReturn 229readFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 230{ 231 int index = 0; 232 int tgt_fd = p->getSyscallArg(tc, index); 233 Addr bufPtr = p->getSyscallArg(tc, index); 234 int nbytes = p->getSyscallArg(tc, index); 235 BufferArg bufArg(bufPtr, nbytes); 236 237 int sim_fd = p->getSimFD(tgt_fd); 238 if (sim_fd < 0) 239 return -EBADF; 240 241 int bytes_read = read(sim_fd, bufArg.bufferPtr(), nbytes); 242 243 if (bytes_read != -1) 244 bufArg.copyOut(tc->getMemProxy()); 245 246 return bytes_read; 247} 248 249SyscallReturn 250writeFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 251{ 252 int index = 0; 253 int tgt_fd = p->getSyscallArg(tc, index); 254 Addr bufPtr = p->getSyscallArg(tc, index); 255 int nbytes = p->getSyscallArg(tc, index); 256 BufferArg bufArg(bufPtr, nbytes); 257 258 int sim_fd = p->getSimFD(tgt_fd); 259 if (sim_fd < 0) 260 return -EBADF; 261 262 bufArg.copyIn(tc->getMemProxy()); 263 264 int bytes_written = write(sim_fd, bufArg.bufferPtr(), nbytes); 265 266 fsync(sim_fd); 267 268 return bytes_written; 269} 270 271 272SyscallReturn 273lseekFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 274{ 275 int index = 0; 276 int tgt_fd = p->getSyscallArg(tc, index); 277 uint64_t offs = p->getSyscallArg(tc, index); 278 int whence = p->getSyscallArg(tc, index); 279 280 int sim_fd = p->getSimFD(tgt_fd); 281 if (sim_fd < 0) 282 return -EBADF; 283 284 off_t result = lseek(sim_fd, offs, whence); 285 286 return (result == (off_t)-1) ? -errno : result; 287} 288 289 290SyscallReturn 291_llseekFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 292{ 293 int index = 0; 294 int tgt_fd = p->getSyscallArg(tc, index); 295 uint64_t offset_high = p->getSyscallArg(tc, index); 296 uint32_t offset_low = p->getSyscallArg(tc, index); 297 Addr result_ptr = p->getSyscallArg(tc, index); 298 int whence = p->getSyscallArg(tc, index); 299 300 int sim_fd = p->getSimFD(tgt_fd); 301 if (sim_fd < 0) 302 return -EBADF; 303 304 uint64_t offset = (offset_high << 32) | offset_low; 305 306 uint64_t result = lseek(sim_fd, offset, whence); 307 result = TheISA::htog(result); 308 309 if (result == (off_t)-1) { 310 //The seek failed. 311 return -errno; 312 } else { 313 // The seek succeeded. 314 // Copy "result" to "result_ptr" 315 // XXX We'll assume that the size of loff_t is 64 bits on the 316 // target platform 317 BufferArg result_buf(result_ptr, sizeof(result)); 318 memcpy(result_buf.bufferPtr(), &result, sizeof(result)); 319 result_buf.copyOut(tc->getMemProxy()); 320 return 0; 321 } 322} 323 324 325SyscallReturn 326munmapFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 327{ 328 // given that we don't really implement mmap, munmap is really easy 329 return 0; 330} 331 332 333const char *hostname = "m5.eecs.umich.edu"; 334 335SyscallReturn 336gethostnameFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 337{ 338 int index = 0; 339 Addr bufPtr = p->getSyscallArg(tc, index); 340 int name_len = p->getSyscallArg(tc, index); 341 BufferArg name(bufPtr, name_len); 342 343 strncpy((char *)name.bufferPtr(), hostname, name_len); 344 345 name.copyOut(tc->getMemProxy()); 346 347 return 0; 348} 349 350SyscallReturn 351getcwdFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 352{ 353 int result = 0; 354 int index = 0; 355 Addr bufPtr = p->getSyscallArg(tc, index); 356 unsigned long size = p->getSyscallArg(tc, index); 357 BufferArg buf(bufPtr, size); 358 359 // Is current working directory defined? 360 string cwd = p->getcwd(); 361 if (!cwd.empty()) { 362 if (cwd.length() >= size) { 363 // Buffer too small 364 return -ERANGE; 365 } 366 strncpy((char *)buf.bufferPtr(), cwd.c_str(), size); 367 result = cwd.length(); 368 } else { 369 if (getcwd((char *)buf.bufferPtr(), size) != NULL) { 370 result = strlen((char *)buf.bufferPtr()); 371 } else { 372 result = -1; 373 } 374 } 375 376 buf.copyOut(tc->getMemProxy()); 377 378 return (result == -1) ? -errno : result; 379} 380 381/// Target open() handler. 382SyscallReturn 383readlinkFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 384 ThreadContext *tc) 385{ 386 return readlinkFunc(desc, callnum, process, tc, 0); 387} 388 389SyscallReturn 390readlinkFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc, 391 int index) 392{ 393 string path; 394 395 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index))) 396 return -EFAULT; 397 398 // Adjust path for current working directory 399 path = p->fullPath(path); 400 401 Addr bufPtr = p->getSyscallArg(tc, index); 402 size_t bufsiz = p->getSyscallArg(tc, index); 403 404 BufferArg buf(bufPtr, bufsiz); 405 406 int result = -1; 407 if (path != "/proc/self/exe") { 408 result = readlink(path.c_str(), (char *)buf.bufferPtr(), bufsiz); 409 } else { 410 // readlink() will return the path of the binary given 411 // with the -c option, however it is possible that this 412 // will still result in incorrect behavior if one binary 413 // runs another, e.g., -c time -o "my_binary" where 414 // my_binary calls readlink(). this is a very unlikely case, 415 // so we issue a warning. 416 warn_once("readlink may yield unexpected results if multiple " 417 "binaries are used\n"); 418 if (strlen(p->progName()) > bufsiz) { 419 // readlink will truncate the contents of the 420 // path to ensure it is no more than bufsiz 421 strncpy((char*)buf.bufferPtr(), p->progName(), bufsiz); 422 result = bufsiz; 423 } else { 424 // return the program's working path rather 425 // than the one for the gem5 binary itself. 426 strcpy((char*)buf.bufferPtr(), p->progName()); 427 result = strlen((char*)buf.bufferPtr()); 428 } 429 } 430 431 buf.copyOut(tc->getMemProxy()); 432 433 return (result == -1) ? -errno : result; 434} 435 436SyscallReturn 437unlinkFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 438{ 439 return unlinkHelper(desc, num, p, tc, 0); 440} 441 442SyscallReturn 443unlinkHelper(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc, 444 int index) 445{ 446 string path; 447 448 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index))) 449 return -EFAULT; 450 451 // Adjust path for current working directory 452 path = p->fullPath(path); 453 454 int result = unlink(path.c_str()); 455 return (result == -1) ? -errno : result; 456} 457 458 459SyscallReturn 460mkdirFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 461{ 462 string path; 463 464 int index = 0; 465 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index))) 466 return -EFAULT; 467 468 // Adjust path for current working directory 469 path = p->fullPath(path); 470 471 mode_t mode = p->getSyscallArg(tc, index); 472 473 int result = mkdir(path.c_str(), mode); 474 return (result == -1) ? -errno : result; 475} 476 477SyscallReturn 478renameFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 479{ 480 string old_name; 481 482 int index = 0; 483 if (!tc->getMemProxy().tryReadString(old_name, p->getSyscallArg(tc, index))) 484 return -EFAULT; 485 486 string new_name; 487 488 if (!tc->getMemProxy().tryReadString(new_name, p->getSyscallArg(tc, index))) 489 return -EFAULT; 490 491 // Adjust path for current working directory 492 old_name = p->fullPath(old_name); 493 new_name = p->fullPath(new_name); 494 495 int64_t result = rename(old_name.c_str(), new_name.c_str()); 496 return (result == -1) ? -errno : result; 497} 498 499SyscallReturn 500truncateFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 501{ 502 string path; 503 504 int index = 0; 505 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index))) 506 return -EFAULT; 507 508 off_t length = p->getSyscallArg(tc, index); 509 510 // Adjust path for current working directory 511 path = p->fullPath(path); 512 513 int result = truncate(path.c_str(), length); 514 return (result == -1) ? -errno : result; 515} 516 517SyscallReturn 518ftruncateFunc(SyscallDesc *desc, int num, 519 LiveProcess *process, ThreadContext *tc) 520{ 521 int index = 0; 522 int tgt_fd = process->getSyscallArg(tc, index); 523 off_t length = process->getSyscallArg(tc, index); 524 525 int sim_fd = process->getSimFD(tgt_fd); 526 if (sim_fd < 0) 527 return -EBADF; 528 529 int result = ftruncate(sim_fd, length); 530 return (result == -1) ? -errno : result; 531} 532 533SyscallReturn 534truncate64Func(SyscallDesc *desc, int num, 535 LiveProcess *process, ThreadContext *tc) 536{ 537 int index = 0; 538 string path; 539 540 if (!tc->getMemProxy().tryReadString(path, process->getSyscallArg(tc, index))) 541 return -EFAULT; 542 543 int64_t length = process->getSyscallArg(tc, index, 64); 544 545 // Adjust path for current working directory 546 path = process->fullPath(path); 547 548#if NO_STAT64 549 int result = truncate(path.c_str(), length); 550#else 551 int result = truncate64(path.c_str(), length); 552#endif 553 return (result == -1) ? -errno : result; 554} 555 556SyscallReturn 557ftruncate64Func(SyscallDesc *desc, int num, 558 LiveProcess *process, ThreadContext *tc) 559{ 560 int index = 0; 561 int tgt_fd = process->getSyscallArg(tc, index); 562 int64_t length = process->getSyscallArg(tc, index, 64); 563 564 int sim_fd = process->getSimFD(tgt_fd); 565 if (sim_fd < 0) 566 return -EBADF; 567 568#if NO_STAT64 569 int result = ftruncate(sim_fd, length); 570#else 571 int result = ftruncate64(sim_fd, length); 572#endif 573 return (result == -1) ? -errno : result; 574} 575 576SyscallReturn 577umaskFunc(SyscallDesc *desc, int num, LiveProcess *process, ThreadContext *tc) 578{ 579 // Letting the simulated program change the simulator's umask seems like 580 // a bad idea. Compromise by just returning the current umask but not 581 // changing anything. 582 mode_t oldMask = umask(0); 583 umask(oldMask); 584 return (int)oldMask; 585} 586 587SyscallReturn 588chownFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 589{ 590 string path; 591 592 int index = 0; 593 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index))) 594 return -EFAULT; 595 596 /* XXX endianess */ 597 uint32_t owner = p->getSyscallArg(tc, index); 598 uid_t hostOwner = owner; 599 uint32_t group = p->getSyscallArg(tc, index); 600 gid_t hostGroup = group; 601 602 // Adjust path for current working directory 603 path = p->fullPath(path); 604 605 int result = chown(path.c_str(), hostOwner, hostGroup); 606 return (result == -1) ? -errno : result; 607} 608 609SyscallReturn 610fchownFunc(SyscallDesc *desc, int num, LiveProcess *process, ThreadContext *tc) 611{ 612 int index = 0; 613 int tgt_fd = process->getSyscallArg(tc, index); 614 615 int sim_fd = process->getSimFD(tgt_fd); 616 if (sim_fd < 0) 617 return -EBADF; 618 619 /* XXX endianess */ 620 uint32_t owner = process->getSyscallArg(tc, index); 621 uid_t hostOwner = owner; 622 uint32_t group = process->getSyscallArg(tc, index); 623 gid_t hostGroup = group; 624 625 int result = fchown(sim_fd, hostOwner, hostGroup); 626 return (result == -1) ? -errno : result; 627} 628 629 630SyscallReturn 631dupFunc(SyscallDesc *desc, int num, LiveProcess *process, ThreadContext *tc) 632{ 633 int index = 0; 634 int tgt_fd = process->getSyscallArg(tc, index); 635 636 int sim_fd = process->getSimFD(tgt_fd); 637 if (sim_fd < 0) 638 return -EBADF; 639 640 FDEntry *fde = process->getFDEntry(tgt_fd); 641 642 int result = dup(sim_fd); 643 return (result == -1) ? -errno : 644 process->allocFD(result, fde->filename, fde->flags, fde->mode, false); 645} 646 647 648SyscallReturn 649fcntlFunc(SyscallDesc *desc, int num, LiveProcess *process, 650 ThreadContext *tc) 651{ 652 int index = 0; 653 int tgt_fd = process->getSyscallArg(tc, index); 654 655 int sim_fd = process->getSimFD(tgt_fd); 656 if (sim_fd < 0) 657 return -EBADF; 658 659 int cmd = process->getSyscallArg(tc, index); 660 switch (cmd) { 661 case 0: // F_DUPFD 662 // if we really wanted to support this, we'd need to do it 663 // in the target fd space. 664 warn("fcntl(%d, F_DUPFD) not supported, error returned\n", tgt_fd); 665 return -EMFILE; 666 667 case 1: // F_GETFD (get close-on-exec flag) 668 case 2: // F_SETFD (set close-on-exec flag) 669 return 0; 670 671 case 3: // F_GETFL (get file flags) 672 case 4: // F_SETFL (set file flags) 673 // not sure if this is totally valid, but we'll pass it through 674 // to the underlying OS 675 warn("fcntl(%d, %d) passed through to host\n", tgt_fd, cmd); 676 return fcntl(sim_fd, cmd); 677 // return 0; 678 679 case 7: // F_GETLK (get lock) 680 case 8: // F_SETLK (set lock) 681 case 9: // F_SETLKW (set lock and wait) 682 // don't mess with file locking... just act like it's OK 683 warn("File lock call (fcntl(%d, %d)) ignored.\n", tgt_fd, cmd); 684 return 0; 685 686 default: 687 warn("Unknown fcntl command %d\n", cmd); 688 return 0; 689 } 690} 691 692SyscallReturn 693fcntl64Func(SyscallDesc *desc, int num, LiveProcess *process, 694 ThreadContext *tc) 695{ 696 int index = 0; 697 int tgt_fd = process->getSyscallArg(tc, index); 698 699 int sim_fd = process->getSimFD(tgt_fd); 700 if (sim_fd < 0) 701 return -EBADF; 702 703 int cmd = process->getSyscallArg(tc, index); 704 switch (cmd) { 705 case 33: //F_GETLK64 706 warn("fcntl64(%d, F_GETLK64) not supported, error returned\n", tgt_fd); 707 return -EMFILE; 708 709 case 34: // F_SETLK64 710 case 35: // F_SETLKW64 711 warn("fcntl64(%d, F_SETLK(W)64) not supported, error returned\n", 712 tgt_fd); 713 return -EMFILE; 714 715 default: 716 // not sure if this is totally valid, but we'll pass it through 717 // to the underlying OS 718 warn("fcntl64(%d, %d) passed through to host\n", tgt_fd, cmd); 719 return fcntl(sim_fd, cmd); 720 // return 0; 721 } 722} 723 724SyscallReturn 725pipePseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 726 ThreadContext *tc) 727{ 728 int fds[2], sim_fds[2]; 729 int pipe_retval = pipe(fds); 730 731 if (pipe_retval < 0) { 732 // error 733 return pipe_retval; 734 } 735 736 sim_fds[0] = process->allocFD(fds[0], "PIPE-READ", O_WRONLY, -1, true); 737 sim_fds[1] = process->allocFD(fds[1], "PIPE-WRITE", O_RDONLY, -1, true); 738 739 process->setReadPipeSource(sim_fds[0], sim_fds[1]); 740 // Alpha Linux convention for pipe() is that fd[0] is returned as 741 // the return value of the function, and fd[1] is returned in r20. 742 tc->setIntReg(SyscallPseudoReturnReg, sim_fds[1]); 743 return sim_fds[0]; 744} 745 746 747SyscallReturn 748getpidPseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 749 ThreadContext *tc) 750{ 751 // Make up a PID. There's no interprocess communication in 752 // fake_syscall mode, so there's no way for a process to know it's 753 // not getting a unique value. 754 755 tc->setIntReg(SyscallPseudoReturnReg, process->ppid()); 756 return process->pid(); 757} 758 759 760SyscallReturn 761getuidPseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 762 ThreadContext *tc) 763{ 764 // Make up a UID and EUID... it shouldn't matter, and we want the 765 // simulation to be deterministic. 766 767 // EUID goes in r20. 768 tc->setIntReg(SyscallPseudoReturnReg, process->euid()); //EUID 769 return process->uid(); // UID 770} 771 772 773SyscallReturn 774getgidPseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 775 ThreadContext *tc) 776{ 777 // Get current group ID. EGID goes in r20. 778 tc->setIntReg(SyscallPseudoReturnReg, process->egid()); //EGID 779 return process->gid(); 780} 781 782 783SyscallReturn 784setuidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 785 ThreadContext *tc) 786{ 787 // can't fathom why a benchmark would call this. 788 int index = 0; 789 warn("Ignoring call to setuid(%d)\n", process->getSyscallArg(tc, index)); 790 return 0; 791} 792 793SyscallReturn 794getpidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 795 ThreadContext *tc) 796{ 797 // Make up a PID. There's no interprocess communication in 798 // fake_syscall mode, so there's no way for a process to know it's 799 // not getting a unique value. 800 801 tc->setIntReg(SyscallPseudoReturnReg, process->ppid()); //PID 802 return process->pid(); 803} 804 805SyscallReturn 806getppidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 807 ThreadContext *tc) 808{ 809 return process->ppid(); 810} 811 812SyscallReturn 813getuidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 814 ThreadContext *tc) 815{ 816 return process->uid(); // UID 817} 818 819SyscallReturn 820geteuidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 821 ThreadContext *tc) 822{ 823 return process->euid(); // UID 824} 825 826SyscallReturn 827getgidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 828 ThreadContext *tc) 829{ 830 return process->gid(); 831} 832 833SyscallReturn 834getegidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 835 ThreadContext *tc) 836{ 837 return process->egid(); 838} 839 840 841SyscallReturn 842cloneFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 843 ThreadContext *tc) 844{ 845 int index = 0; 846 IntReg flags = process->getSyscallArg(tc, index); 847 IntReg newStack = process->getSyscallArg(tc, index); 848 849 DPRINTF(SyscallVerbose, "In sys_clone:\n"); 850 DPRINTF(SyscallVerbose, " Flags=%llx\n", flags); 851 DPRINTF(SyscallVerbose, " Child stack=%llx\n", newStack); 852 853 854 if (flags != 0x10f00) { 855 warn("This sys_clone implementation assumes flags " 856 "CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD " 857 "(0x10f00), and may not work correctly with given flags " 858 "0x%llx\n", flags); 859 } 860 861 ThreadContext* ctc; // child thread context 862 if ( ( ctc = process->findFreeContext() ) != NULL ) { 863 DPRINTF(SyscallVerbose, " Found unallocated thread context\n"); 864 865 ctc->clearArchRegs(); 866 867 // Arch-specific cloning code 868 #if THE_ISA == ALPHA_ISA or THE_ISA == X86_ISA 869 // Cloning the misc. regs for these archs is enough 870 TheISA::copyMiscRegs(tc, ctc); 871 #elif THE_ISA == SPARC_ISA 872 TheISA::copyRegs(tc, ctc); 873 874 // TODO: Explain what this code actually does :-) 875 ctc->setIntReg(NumIntArchRegs + 6, 0); 876 ctc->setIntReg(NumIntArchRegs + 4, 0); 877 ctc->setIntReg(NumIntArchRegs + 3, NWindows - 2); 878 ctc->setIntReg(NumIntArchRegs + 5, NWindows); 879 ctc->setMiscReg(MISCREG_CWP, 0); 880 ctc->setIntReg(NumIntArchRegs + 7, 0); 881 ctc->setMiscRegNoEffect(MISCREG_TL, 0); 882 ctc->setMiscReg(MISCREG_ASI, ASI_PRIMARY); 883 884 for (int y = 8; y < 32; y++) 885 ctc->setIntReg(y, tc->readIntReg(y)); 886 #elif THE_ISA == ARM_ISA 887 TheISA::copyRegs(tc, ctc); 888 #else 889 fatal("sys_clone is not implemented for this ISA\n"); 890 #endif 891 892 // Set up stack register 893 ctc->setIntReg(TheISA::StackPointerReg, newStack); 894 895 // Set up syscall return values in parent and child 896 ctc->setIntReg(ReturnValueReg, 0); // return value, child 897 898 // Alpha needs SyscallSuccessReg=0 in child 899 #if THE_ISA == ALPHA_ISA 900 ctc->setIntReg(TheISA::SyscallSuccessReg, 0); 901 #endif 902 903 // In SPARC/Linux, clone returns 0 on pseudo-return register if 904 // parent, non-zero if child 905 #if THE_ISA == SPARC_ISA 906 tc->setIntReg(TheISA::SyscallPseudoReturnReg, 0); 907 ctc->setIntReg(TheISA::SyscallPseudoReturnReg, 1); 908 #endif 909 910 ctc->pcState(tc->nextInstAddr()); 911 912 ctc->activate(); 913 914 // Should return nonzero child TID in parent's syscall return register, 915 // but for our pthread library any non-zero value will work 916 return 1; 917 } else { 918 fatal("Called sys_clone, but no unallocated thread contexts found!\n"); 919 return 0; 920 } 921} 922 923SyscallReturn 924accessFunc(SyscallDesc *desc, int callnum, LiveProcess *p, ThreadContext *tc, 925 int index) 926{ 927 string path; 928 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index))) 929 return -EFAULT; 930 931 // Adjust path for current working directory 932 path = p->fullPath(path); 933 934 mode_t mode = p->getSyscallArg(tc, index); 935 936 int result = access(path.c_str(), mode); 937 return (result == -1) ? -errno : result; 938} 939 940SyscallReturn 941accessFunc(SyscallDesc *desc, int callnum, LiveProcess *p, ThreadContext *tc) 942{ 943 return accessFunc(desc, callnum, p, tc, 0); 944} 945 946