syscall_emul.cc revision 11379:bfe4c2a8ad36
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 return -errno; 311 // Assuming that the size of loff_t is 64 bits on the target platform 312 BufferArg result_buf(result_ptr, sizeof(result)); 313 memcpy(result_buf.bufferPtr(), &result, sizeof(result)); 314 result_buf.copyOut(tc->getMemProxy()); 315 return 0; 316} 317 318 319SyscallReturn 320munmapFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 321{ 322 // given that we don't really implement mmap, munmap is really easy 323 return 0; 324} 325 326 327const char *hostname = "m5.eecs.umich.edu"; 328 329SyscallReturn 330gethostnameFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 331{ 332 int index = 0; 333 Addr bufPtr = p->getSyscallArg(tc, index); 334 int name_len = p->getSyscallArg(tc, index); 335 BufferArg name(bufPtr, name_len); 336 337 strncpy((char *)name.bufferPtr(), hostname, name_len); 338 339 name.copyOut(tc->getMemProxy()); 340 341 return 0; 342} 343 344SyscallReturn 345getcwdFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 346{ 347 int result = 0; 348 int index = 0; 349 Addr bufPtr = p->getSyscallArg(tc, index); 350 unsigned long size = p->getSyscallArg(tc, index); 351 BufferArg buf(bufPtr, size); 352 353 // Is current working directory defined? 354 string cwd = p->getcwd(); 355 if (!cwd.empty()) { 356 if (cwd.length() >= size) { 357 // Buffer too small 358 return -ERANGE; 359 } 360 strncpy((char *)buf.bufferPtr(), cwd.c_str(), size); 361 result = cwd.length(); 362 } else { 363 if (getcwd((char *)buf.bufferPtr(), size) != NULL) { 364 result = strlen((char *)buf.bufferPtr()); 365 } else { 366 result = -1; 367 } 368 } 369 370 buf.copyOut(tc->getMemProxy()); 371 372 return (result == -1) ? -errno : result; 373} 374 375/// Target open() handler. 376SyscallReturn 377readlinkFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 378 ThreadContext *tc) 379{ 380 return readlinkFunc(desc, callnum, process, tc, 0); 381} 382 383SyscallReturn 384readlinkFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc, 385 int index) 386{ 387 string path; 388 389 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index))) 390 return -EFAULT; 391 392 // Adjust path for current working directory 393 path = p->fullPath(path); 394 395 Addr bufPtr = p->getSyscallArg(tc, index); 396 size_t bufsiz = p->getSyscallArg(tc, index); 397 398 BufferArg buf(bufPtr, bufsiz); 399 400 int result = -1; 401 if (path != "/proc/self/exe") { 402 result = readlink(path.c_str(), (char *)buf.bufferPtr(), bufsiz); 403 } else { 404 // Emulate readlink() called on '/proc/self/exe' should return the 405 // absolute path of the binary running in the simulated system (the 406 // LiveProcess' executable). It is possible that using this path in 407 // the simulated system will result in unexpected behavior if: 408 // 1) One binary runs another (e.g., -c time -o "my_binary"), and 409 // called binary calls readlink(). 410 // 2) The host's full path to the running benchmark changes from one 411 // simulation to another. This can result in different simulated 412 // performance since the simulated system will process the binary 413 // path differently, even if the binary itself does not change. 414 415 // Get the absolute canonical path to the running application 416 char real_path[PATH_MAX]; 417 char *check_real_path = realpath(p->progName(), real_path); 418 if (!check_real_path) { 419 fatal("readlink('/proc/self/exe') unable to resolve path to " 420 "executable: %s", p->progName()); 421 } 422 strncpy((char*)buf.bufferPtr(), real_path, bufsiz); 423 size_t real_path_len = strlen(real_path); 424 if (real_path_len > bufsiz) { 425 // readlink will truncate the contents of the 426 // path to ensure it is no more than bufsiz 427 result = bufsiz; 428 } else { 429 result = real_path_len; 430 } 431 432 // Issue a warning about potential unexpected results 433 warn_once("readlink() called on '/proc/self/exe' may yield unexpected " 434 "results in various settings.\n Returning '%s'\n", 435 (char*)buf.bufferPtr()); 436 } 437 438 buf.copyOut(tc->getMemProxy()); 439 440 return (result == -1) ? -errno : result; 441} 442 443SyscallReturn 444unlinkFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 445{ 446 return unlinkHelper(desc, num, p, tc, 0); 447} 448 449SyscallReturn 450unlinkHelper(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc, 451 int index) 452{ 453 string path; 454 455 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index))) 456 return -EFAULT; 457 458 // Adjust path for current working directory 459 path = p->fullPath(path); 460 461 int result = unlink(path.c_str()); 462 return (result == -1) ? -errno : result; 463} 464 465 466SyscallReturn 467mkdirFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 468{ 469 string path; 470 471 int index = 0; 472 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index))) 473 return -EFAULT; 474 475 // Adjust path for current working directory 476 path = p->fullPath(path); 477 478 mode_t mode = p->getSyscallArg(tc, index); 479 480 int result = mkdir(path.c_str(), mode); 481 return (result == -1) ? -errno : result; 482} 483 484SyscallReturn 485renameFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 486{ 487 string old_name; 488 489 int index = 0; 490 if (!tc->getMemProxy().tryReadString(old_name, p->getSyscallArg(tc, index))) 491 return -EFAULT; 492 493 string new_name; 494 495 if (!tc->getMemProxy().tryReadString(new_name, p->getSyscallArg(tc, index))) 496 return -EFAULT; 497 498 // Adjust path for current working directory 499 old_name = p->fullPath(old_name); 500 new_name = p->fullPath(new_name); 501 502 int64_t result = rename(old_name.c_str(), new_name.c_str()); 503 return (result == -1) ? -errno : result; 504} 505 506SyscallReturn 507truncateFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 508{ 509 string path; 510 511 int index = 0; 512 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index))) 513 return -EFAULT; 514 515 off_t length = p->getSyscallArg(tc, index); 516 517 // Adjust path for current working directory 518 path = p->fullPath(path); 519 520 int result = truncate(path.c_str(), length); 521 return (result == -1) ? -errno : result; 522} 523 524SyscallReturn 525ftruncateFunc(SyscallDesc *desc, int num, 526 LiveProcess *process, ThreadContext *tc) 527{ 528 int index = 0; 529 int tgt_fd = process->getSyscallArg(tc, index); 530 off_t length = process->getSyscallArg(tc, index); 531 532 int sim_fd = process->getSimFD(tgt_fd); 533 if (sim_fd < 0) 534 return -EBADF; 535 536 int result = ftruncate(sim_fd, length); 537 return (result == -1) ? -errno : result; 538} 539 540SyscallReturn 541truncate64Func(SyscallDesc *desc, int num, 542 LiveProcess *process, ThreadContext *tc) 543{ 544 int index = 0; 545 string path; 546 547 if (!tc->getMemProxy().tryReadString(path, process->getSyscallArg(tc, index))) 548 return -EFAULT; 549 550 int64_t length = process->getSyscallArg(tc, index, 64); 551 552 // Adjust path for current working directory 553 path = process->fullPath(path); 554 555#if NO_STAT64 556 int result = truncate(path.c_str(), length); 557#else 558 int result = truncate64(path.c_str(), length); 559#endif 560 return (result == -1) ? -errno : result; 561} 562 563SyscallReturn 564ftruncate64Func(SyscallDesc *desc, int num, 565 LiveProcess *process, ThreadContext *tc) 566{ 567 int index = 0; 568 int tgt_fd = process->getSyscallArg(tc, index); 569 int64_t length = process->getSyscallArg(tc, index, 64); 570 571 int sim_fd = process->getSimFD(tgt_fd); 572 if (sim_fd < 0) 573 return -EBADF; 574 575#if NO_STAT64 576 int result = ftruncate(sim_fd, length); 577#else 578 int result = ftruncate64(sim_fd, length); 579#endif 580 return (result == -1) ? -errno : result; 581} 582 583SyscallReturn 584umaskFunc(SyscallDesc *desc, int num, LiveProcess *process, ThreadContext *tc) 585{ 586 // Letting the simulated program change the simulator's umask seems like 587 // a bad idea. Compromise by just returning the current umask but not 588 // changing anything. 589 mode_t oldMask = umask(0); 590 umask(oldMask); 591 return (int)oldMask; 592} 593 594SyscallReturn 595chownFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 596{ 597 string path; 598 599 int index = 0; 600 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index))) 601 return -EFAULT; 602 603 /* XXX endianess */ 604 uint32_t owner = p->getSyscallArg(tc, index); 605 uid_t hostOwner = owner; 606 uint32_t group = p->getSyscallArg(tc, index); 607 gid_t hostGroup = group; 608 609 // Adjust path for current working directory 610 path = p->fullPath(path); 611 612 int result = chown(path.c_str(), hostOwner, hostGroup); 613 return (result == -1) ? -errno : result; 614} 615 616SyscallReturn 617fchownFunc(SyscallDesc *desc, int num, LiveProcess *process, ThreadContext *tc) 618{ 619 int index = 0; 620 int tgt_fd = process->getSyscallArg(tc, index); 621 622 int sim_fd = process->getSimFD(tgt_fd); 623 if (sim_fd < 0) 624 return -EBADF; 625 626 /* XXX endianess */ 627 uint32_t owner = process->getSyscallArg(tc, index); 628 uid_t hostOwner = owner; 629 uint32_t group = process->getSyscallArg(tc, index); 630 gid_t hostGroup = group; 631 632 int result = fchown(sim_fd, hostOwner, hostGroup); 633 return (result == -1) ? -errno : result; 634} 635 636 637SyscallReturn 638dupFunc(SyscallDesc *desc, int num, LiveProcess *process, ThreadContext *tc) 639{ 640 int index = 0; 641 int tgt_fd = process->getSyscallArg(tc, index); 642 643 int sim_fd = process->getSimFD(tgt_fd); 644 if (sim_fd < 0) 645 return -EBADF; 646 647 FDEntry *fde = process->getFDEntry(tgt_fd); 648 649 int result = dup(sim_fd); 650 return (result == -1) ? -errno : 651 process->allocFD(result, fde->filename, fde->flags, fde->mode, false); 652} 653 654 655SyscallReturn 656fcntlFunc(SyscallDesc *desc, int num, LiveProcess *process, 657 ThreadContext *tc) 658{ 659 int index = 0; 660 int tgt_fd = process->getSyscallArg(tc, index); 661 662 int sim_fd = process->getSimFD(tgt_fd); 663 if (sim_fd < 0) 664 return -EBADF; 665 666 int cmd = process->getSyscallArg(tc, index); 667 switch (cmd) { 668 case 0: // F_DUPFD 669 // if we really wanted to support this, we'd need to do it 670 // in the target fd space. 671 warn("fcntl(%d, F_DUPFD) not supported, error returned\n", tgt_fd); 672 return -EMFILE; 673 674 case 1: // F_GETFD (get close-on-exec flag) 675 case 2: // F_SETFD (set close-on-exec flag) 676 return 0; 677 678 case 3: // F_GETFL (get file flags) 679 case 4: // F_SETFL (set file flags) 680 // not sure if this is totally valid, but we'll pass it through 681 // to the underlying OS 682 warn("fcntl(%d, %d) passed through to host\n", tgt_fd, cmd); 683 return fcntl(sim_fd, cmd); 684 // return 0; 685 686 case 7: // F_GETLK (get lock) 687 case 8: // F_SETLK (set lock) 688 case 9: // F_SETLKW (set lock and wait) 689 // don't mess with file locking... just act like it's OK 690 warn("File lock call (fcntl(%d, %d)) ignored.\n", tgt_fd, cmd); 691 return 0; 692 693 default: 694 warn("Unknown fcntl command %d\n", cmd); 695 return 0; 696 } 697} 698 699SyscallReturn 700fcntl64Func(SyscallDesc *desc, int num, LiveProcess *process, 701 ThreadContext *tc) 702{ 703 int index = 0; 704 int tgt_fd = process->getSyscallArg(tc, index); 705 706 int sim_fd = process->getSimFD(tgt_fd); 707 if (sim_fd < 0) 708 return -EBADF; 709 710 int cmd = process->getSyscallArg(tc, index); 711 switch (cmd) { 712 case 33: //F_GETLK64 713 warn("fcntl64(%d, F_GETLK64) not supported, error returned\n", tgt_fd); 714 return -EMFILE; 715 716 case 34: // F_SETLK64 717 case 35: // F_SETLKW64 718 warn("fcntl64(%d, F_SETLK(W)64) not supported, error returned\n", 719 tgt_fd); 720 return -EMFILE; 721 722 default: 723 // not sure if this is totally valid, but we'll pass it through 724 // to the underlying OS 725 warn("fcntl64(%d, %d) passed through to host\n", tgt_fd, cmd); 726 return fcntl(sim_fd, cmd); 727 // return 0; 728 } 729} 730 731SyscallReturn 732pipePseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 733 ThreadContext *tc) 734{ 735 int fds[2], sim_fds[2]; 736 int pipe_retval = pipe(fds); 737 738 if (pipe_retval < 0) { 739 // error 740 return pipe_retval; 741 } 742 743 sim_fds[0] = process->allocFD(fds[0], "PIPE-READ", O_WRONLY, -1, true); 744 sim_fds[1] = process->allocFD(fds[1], "PIPE-WRITE", O_RDONLY, -1, true); 745 746 process->setReadPipeSource(sim_fds[0], sim_fds[1]); 747 // Alpha Linux convention for pipe() is that fd[0] is returned as 748 // the return value of the function, and fd[1] is returned in r20. 749 tc->setIntReg(SyscallPseudoReturnReg, sim_fds[1]); 750 return sim_fds[0]; 751} 752 753 754SyscallReturn 755getpidPseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 756 ThreadContext *tc) 757{ 758 // Make up a PID. There's no interprocess communication in 759 // fake_syscall mode, so there's no way for a process to know it's 760 // not getting a unique value. 761 762 tc->setIntReg(SyscallPseudoReturnReg, process->ppid()); 763 return process->pid(); 764} 765 766 767SyscallReturn 768getuidPseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 769 ThreadContext *tc) 770{ 771 // Make up a UID and EUID... it shouldn't matter, and we want the 772 // simulation to be deterministic. 773 774 // EUID goes in r20. 775 tc->setIntReg(SyscallPseudoReturnReg, process->euid()); //EUID 776 return process->uid(); // UID 777} 778 779 780SyscallReturn 781getgidPseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 782 ThreadContext *tc) 783{ 784 // Get current group ID. EGID goes in r20. 785 tc->setIntReg(SyscallPseudoReturnReg, process->egid()); //EGID 786 return process->gid(); 787} 788 789 790SyscallReturn 791setuidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 792 ThreadContext *tc) 793{ 794 // can't fathom why a benchmark would call this. 795 int index = 0; 796 warn("Ignoring call to setuid(%d)\n", process->getSyscallArg(tc, index)); 797 return 0; 798} 799 800SyscallReturn 801getpidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 802 ThreadContext *tc) 803{ 804 // Make up a PID. There's no interprocess communication in 805 // fake_syscall mode, so there's no way for a process to know it's 806 // not getting a unique value. 807 808 tc->setIntReg(SyscallPseudoReturnReg, process->ppid()); //PID 809 return process->pid(); 810} 811 812SyscallReturn 813getppidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 814 ThreadContext *tc) 815{ 816 return process->ppid(); 817} 818 819SyscallReturn 820getuidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 821 ThreadContext *tc) 822{ 823 return process->uid(); // UID 824} 825 826SyscallReturn 827geteuidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 828 ThreadContext *tc) 829{ 830 return process->euid(); // UID 831} 832 833SyscallReturn 834getgidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 835 ThreadContext *tc) 836{ 837 return process->gid(); 838} 839 840SyscallReturn 841getegidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 842 ThreadContext *tc) 843{ 844 return process->egid(); 845} 846 847 848SyscallReturn 849cloneFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 850 ThreadContext *tc) 851{ 852 int index = 0; 853 IntReg flags = process->getSyscallArg(tc, index); 854 IntReg newStack = process->getSyscallArg(tc, index); 855 856 DPRINTF(SyscallVerbose, "In sys_clone:\n"); 857 DPRINTF(SyscallVerbose, " Flags=%llx\n", flags); 858 DPRINTF(SyscallVerbose, " Child stack=%llx\n", newStack); 859 860 861 if (flags != 0x10f00) { 862 warn("This sys_clone implementation assumes flags " 863 "CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD " 864 "(0x10f00), and may not work correctly with given flags " 865 "0x%llx\n", flags); 866 } 867 868 ThreadContext* ctc; // child thread context 869 if ( ( ctc = process->findFreeContext() ) != NULL ) { 870 DPRINTF(SyscallVerbose, " Found unallocated thread context\n"); 871 872 ctc->clearArchRegs(); 873 874 // Arch-specific cloning code 875 #if THE_ISA == ALPHA_ISA or THE_ISA == X86_ISA 876 // Cloning the misc. regs for these archs is enough 877 TheISA::copyMiscRegs(tc, ctc); 878 #elif THE_ISA == SPARC_ISA 879 TheISA::copyRegs(tc, ctc); 880 881 // TODO: Explain what this code actually does :-) 882 ctc->setIntReg(NumIntArchRegs + 6, 0); 883 ctc->setIntReg(NumIntArchRegs + 4, 0); 884 ctc->setIntReg(NumIntArchRegs + 3, NWindows - 2); 885 ctc->setIntReg(NumIntArchRegs + 5, NWindows); 886 ctc->setMiscReg(MISCREG_CWP, 0); 887 ctc->setIntReg(NumIntArchRegs + 7, 0); 888 ctc->setMiscRegNoEffect(MISCREG_TL, 0); 889 ctc->setMiscReg(MISCREG_ASI, ASI_PRIMARY); 890 891 for (int y = 8; y < 32; y++) 892 ctc->setIntReg(y, tc->readIntReg(y)); 893 #elif THE_ISA == ARM_ISA 894 TheISA::copyRegs(tc, ctc); 895 #else 896 fatal("sys_clone is not implemented for this ISA\n"); 897 #endif 898 899 // Set up stack register 900 ctc->setIntReg(TheISA::StackPointerReg, newStack); 901 902 // Set up syscall return values in parent and child 903 ctc->setIntReg(ReturnValueReg, 0); // return value, child 904 905 // Alpha needs SyscallSuccessReg=0 in child 906 #if THE_ISA == ALPHA_ISA 907 ctc->setIntReg(TheISA::SyscallSuccessReg, 0); 908 #endif 909 910 // In SPARC/Linux, clone returns 0 on pseudo-return register if 911 // parent, non-zero if child 912 #if THE_ISA == SPARC_ISA 913 tc->setIntReg(TheISA::SyscallPseudoReturnReg, 0); 914 ctc->setIntReg(TheISA::SyscallPseudoReturnReg, 1); 915 #endif 916 917 ctc->pcState(tc->nextInstAddr()); 918 919 ctc->activate(); 920 921 // Should return nonzero child TID in parent's syscall return register, 922 // but for our pthread library any non-zero value will work 923 return 1; 924 } else { 925 fatal("Called sys_clone, but no unallocated thread contexts found!\n"); 926 return 0; 927 } 928} 929 930SyscallReturn 931accessFunc(SyscallDesc *desc, int callnum, LiveProcess *p, ThreadContext *tc, 932 int index) 933{ 934 string path; 935 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index))) 936 return -EFAULT; 937 938 // Adjust path for current working directory 939 path = p->fullPath(path); 940 941 mode_t mode = p->getSyscallArg(tc, index); 942 943 int result = access(path.c_str(), mode); 944 return (result == -1) ? -errno : result; 945} 946 947SyscallReturn 948accessFunc(SyscallDesc *desc, int callnum, LiveProcess *p, ThreadContext *tc) 949{ 950 return accessFunc(desc, callnum, p, tc, 0); 951} 952 953