syscall_emul.cc revision 10932
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 } 369 else { 370 if (getcwd((char *)buf.bufferPtr(), size) != NULL) { 371 result = strlen((char *)buf.bufferPtr()); 372 } 373 else { 374 result = -1; 375 } 376 } 377 378 buf.copyOut(tc->getMemProxy()); 379 380 return (result == -1) ? -errno : result; 381} 382 383/// Target open() handler. 384SyscallReturn 385readlinkFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 386 ThreadContext *tc) 387{ 388 return readlinkFunc(desc, callnum, process, tc, 0); 389} 390 391SyscallReturn 392readlinkFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc, 393 int index) 394{ 395 string path; 396 397 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index))) 398 return -EFAULT; 399 400 // Adjust path for current working directory 401 path = p->fullPath(path); 402 403 Addr bufPtr = p->getSyscallArg(tc, index); 404 size_t bufsiz = p->getSyscallArg(tc, index); 405 406 BufferArg buf(bufPtr, bufsiz); 407 408 int result = readlink(path.c_str(), (char *)buf.bufferPtr(), bufsiz); 409 410 buf.copyOut(tc->getMemProxy()); 411 412 return (result == -1) ? -errno : result; 413} 414 415SyscallReturn 416unlinkFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 417{ 418 return unlinkHelper(desc, num, p, tc, 0); 419} 420 421SyscallReturn 422unlinkHelper(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc, 423 int index) 424{ 425 string path; 426 427 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index))) 428 return -EFAULT; 429 430 // Adjust path for current working directory 431 path = p->fullPath(path); 432 433 int result = unlink(path.c_str()); 434 return (result == -1) ? -errno : result; 435} 436 437 438SyscallReturn 439mkdirFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 440{ 441 string path; 442 443 int index = 0; 444 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index))) 445 return -EFAULT; 446 447 // Adjust path for current working directory 448 path = p->fullPath(path); 449 450 mode_t mode = p->getSyscallArg(tc, index); 451 452 int result = mkdir(path.c_str(), mode); 453 return (result == -1) ? -errno : result; 454} 455 456SyscallReturn 457renameFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 458{ 459 string old_name; 460 461 int index = 0; 462 if (!tc->getMemProxy().tryReadString(old_name, p->getSyscallArg(tc, index))) 463 return -EFAULT; 464 465 string new_name; 466 467 if (!tc->getMemProxy().tryReadString(new_name, p->getSyscallArg(tc, index))) 468 return -EFAULT; 469 470 // Adjust path for current working directory 471 old_name = p->fullPath(old_name); 472 new_name = p->fullPath(new_name); 473 474 int64_t result = rename(old_name.c_str(), new_name.c_str()); 475 return (result == -1) ? -errno : result; 476} 477 478SyscallReturn 479truncateFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 480{ 481 string path; 482 483 int index = 0; 484 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index))) 485 return -EFAULT; 486 487 off_t length = p->getSyscallArg(tc, index); 488 489 // Adjust path for current working directory 490 path = p->fullPath(path); 491 492 int result = truncate(path.c_str(), length); 493 return (result == -1) ? -errno : result; 494} 495 496SyscallReturn 497ftruncateFunc(SyscallDesc *desc, int num, 498 LiveProcess *process, ThreadContext *tc) 499{ 500 int index = 0; 501 int tgt_fd = process->getSyscallArg(tc, index); 502 off_t length = process->getSyscallArg(tc, index); 503 504 int sim_fd = process->getSimFD(tgt_fd); 505 if (sim_fd < 0) 506 return -EBADF; 507 508 int result = ftruncate(sim_fd, length); 509 return (result == -1) ? -errno : result; 510} 511 512SyscallReturn 513truncate64Func(SyscallDesc *desc, int num, 514 LiveProcess *process, ThreadContext *tc) 515{ 516 int index = 0; 517 string path; 518 519 if (!tc->getMemProxy().tryReadString(path, process->getSyscallArg(tc, index))) 520 return -EFAULT; 521 522 int64_t length = process->getSyscallArg(tc, index, 64); 523 524 // Adjust path for current working directory 525 path = process->fullPath(path); 526 527#if NO_STAT64 528 int result = truncate(path.c_str(), length); 529#else 530 int result = truncate64(path.c_str(), length); 531#endif 532 return (result == -1) ? -errno : result; 533} 534 535SyscallReturn 536ftruncate64Func(SyscallDesc *desc, int num, 537 LiveProcess *process, ThreadContext *tc) 538{ 539 int index = 0; 540 int tgt_fd = process->getSyscallArg(tc, index); 541 int64_t length = process->getSyscallArg(tc, index, 64); 542 543 int sim_fd = process->getSimFD(tgt_fd); 544 if (sim_fd < 0) 545 return -EBADF; 546 547#if NO_STAT64 548 int result = ftruncate(sim_fd, length); 549#else 550 int result = ftruncate64(sim_fd, length); 551#endif 552 return (result == -1) ? -errno : result; 553} 554 555SyscallReturn 556umaskFunc(SyscallDesc *desc, int num, LiveProcess *process, ThreadContext *tc) 557{ 558 // Letting the simulated program change the simulator's umask seems like 559 // a bad idea. Compromise by just returning the current umask but not 560 // changing anything. 561 mode_t oldMask = umask(0); 562 umask(oldMask); 563 return (int)oldMask; 564} 565 566SyscallReturn 567chownFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc) 568{ 569 string path; 570 571 int index = 0; 572 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index))) 573 return -EFAULT; 574 575 /* XXX endianess */ 576 uint32_t owner = p->getSyscallArg(tc, index); 577 uid_t hostOwner = owner; 578 uint32_t group = p->getSyscallArg(tc, index); 579 gid_t hostGroup = group; 580 581 // Adjust path for current working directory 582 path = p->fullPath(path); 583 584 int result = chown(path.c_str(), hostOwner, hostGroup); 585 return (result == -1) ? -errno : result; 586} 587 588SyscallReturn 589fchownFunc(SyscallDesc *desc, int num, LiveProcess *process, ThreadContext *tc) 590{ 591 int index = 0; 592 int tgt_fd = process->getSyscallArg(tc, index); 593 594 int sim_fd = process->getSimFD(tgt_fd); 595 if (sim_fd < 0) 596 return -EBADF; 597 598 /* XXX endianess */ 599 uint32_t owner = process->getSyscallArg(tc, index); 600 uid_t hostOwner = owner; 601 uint32_t group = process->getSyscallArg(tc, index); 602 gid_t hostGroup = group; 603 604 int result = fchown(sim_fd, hostOwner, hostGroup); 605 return (result == -1) ? -errno : result; 606} 607 608 609SyscallReturn 610dupFunc(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 FDEntry *fde = process->getFDEntry(tgt_fd); 620 621 int result = dup(sim_fd); 622 return (result == -1) ? -errno : 623 process->allocFD(result, fde->filename, fde->flags, fde->mode, false); 624} 625 626 627SyscallReturn 628fcntlFunc(SyscallDesc *desc, int num, LiveProcess *process, 629 ThreadContext *tc) 630{ 631 int index = 0; 632 int tgt_fd = process->getSyscallArg(tc, index); 633 634 int sim_fd = process->getSimFD(tgt_fd); 635 if (sim_fd < 0) 636 return -EBADF; 637 638 int cmd = process->getSyscallArg(tc, index); 639 switch (cmd) { 640 case 0: // F_DUPFD 641 // if we really wanted to support this, we'd need to do it 642 // in the target fd space. 643 warn("fcntl(%d, F_DUPFD) not supported, error returned\n", tgt_fd); 644 return -EMFILE; 645 646 case 1: // F_GETFD (get close-on-exec flag) 647 case 2: // F_SETFD (set close-on-exec flag) 648 return 0; 649 650 case 3: // F_GETFL (get file flags) 651 case 4: // F_SETFL (set file flags) 652 // not sure if this is totally valid, but we'll pass it through 653 // to the underlying OS 654 warn("fcntl(%d, %d) passed through to host\n", tgt_fd, cmd); 655 return fcntl(sim_fd, cmd); 656 // return 0; 657 658 case 7: // F_GETLK (get lock) 659 case 8: // F_SETLK (set lock) 660 case 9: // F_SETLKW (set lock and wait) 661 // don't mess with file locking... just act like it's OK 662 warn("File lock call (fcntl(%d, %d)) ignored.\n", tgt_fd, cmd); 663 return 0; 664 665 default: 666 warn("Unknown fcntl command %d\n", cmd); 667 return 0; 668 } 669} 670 671SyscallReturn 672fcntl64Func(SyscallDesc *desc, int num, LiveProcess *process, 673 ThreadContext *tc) 674{ 675 int index = 0; 676 int tgt_fd = process->getSyscallArg(tc, index); 677 678 int sim_fd = process->getSimFD(tgt_fd); 679 if (sim_fd < 0) 680 return -EBADF; 681 682 int cmd = process->getSyscallArg(tc, index); 683 switch (cmd) { 684 case 33: //F_GETLK64 685 warn("fcntl64(%d, F_GETLK64) not supported, error returned\n", tgt_fd); 686 return -EMFILE; 687 688 case 34: // F_SETLK64 689 case 35: // F_SETLKW64 690 warn("fcntl64(%d, F_SETLK(W)64) not supported, error returned\n", 691 tgt_fd); 692 return -EMFILE; 693 694 default: 695 // not sure if this is totally valid, but we'll pass it through 696 // to the underlying OS 697 warn("fcntl64(%d, %d) passed through to host\n", tgt_fd, cmd); 698 return fcntl(sim_fd, cmd); 699 // return 0; 700 } 701} 702 703SyscallReturn 704pipePseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 705 ThreadContext *tc) 706{ 707 int fds[2], sim_fds[2]; 708 int pipe_retval = pipe(fds); 709 710 if (pipe_retval < 0) { 711 // error 712 return pipe_retval; 713 } 714 715 sim_fds[0] = process->allocFD(fds[0], "PIPE-READ", O_WRONLY, -1, true); 716 sim_fds[1] = process->allocFD(fds[1], "PIPE-WRITE", O_RDONLY, -1, true); 717 718 process->setReadPipeSource(sim_fds[0], sim_fds[1]); 719 // Alpha Linux convention for pipe() is that fd[0] is returned as 720 // the return value of the function, and fd[1] is returned in r20. 721 tc->setIntReg(SyscallPseudoReturnReg, sim_fds[1]); 722 return sim_fds[0]; 723} 724 725 726SyscallReturn 727getpidPseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 728 ThreadContext *tc) 729{ 730 // Make up a PID. There's no interprocess communication in 731 // fake_syscall mode, so there's no way for a process to know it's 732 // not getting a unique value. 733 734 tc->setIntReg(SyscallPseudoReturnReg, process->ppid()); 735 return process->pid(); 736} 737 738 739SyscallReturn 740getuidPseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 741 ThreadContext *tc) 742{ 743 // Make up a UID and EUID... it shouldn't matter, and we want the 744 // simulation to be deterministic. 745 746 // EUID goes in r20. 747 tc->setIntReg(SyscallPseudoReturnReg, process->euid()); //EUID 748 return process->uid(); // UID 749} 750 751 752SyscallReturn 753getgidPseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 754 ThreadContext *tc) 755{ 756 // Get current group ID. EGID goes in r20. 757 tc->setIntReg(SyscallPseudoReturnReg, process->egid()); //EGID 758 return process->gid(); 759} 760 761 762SyscallReturn 763setuidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 764 ThreadContext *tc) 765{ 766 // can't fathom why a benchmark would call this. 767 int index = 0; 768 warn("Ignoring call to setuid(%d)\n", process->getSyscallArg(tc, index)); 769 return 0; 770} 771 772SyscallReturn 773getpidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 774 ThreadContext *tc) 775{ 776 // Make up a PID. There's no interprocess communication in 777 // fake_syscall mode, so there's no way for a process to know it's 778 // not getting a unique value. 779 780 tc->setIntReg(SyscallPseudoReturnReg, process->ppid()); //PID 781 return process->pid(); 782} 783 784SyscallReturn 785getppidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 786 ThreadContext *tc) 787{ 788 return process->ppid(); 789} 790 791SyscallReturn 792getuidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 793 ThreadContext *tc) 794{ 795 return process->uid(); // UID 796} 797 798SyscallReturn 799geteuidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 800 ThreadContext *tc) 801{ 802 return process->euid(); // UID 803} 804 805SyscallReturn 806getgidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 807 ThreadContext *tc) 808{ 809 return process->gid(); 810} 811 812SyscallReturn 813getegidFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 814 ThreadContext *tc) 815{ 816 return process->egid(); 817} 818 819 820SyscallReturn 821cloneFunc(SyscallDesc *desc, int callnum, LiveProcess *process, 822 ThreadContext *tc) 823{ 824 int index = 0; 825 IntReg flags = process->getSyscallArg(tc, index); 826 IntReg newStack = process->getSyscallArg(tc, index); 827 828 DPRINTF(SyscallVerbose, "In sys_clone:\n"); 829 DPRINTF(SyscallVerbose, " Flags=%llx\n", flags); 830 DPRINTF(SyscallVerbose, " Child stack=%llx\n", newStack); 831 832 833 if (flags != 0x10f00) { 834 warn("This sys_clone implementation assumes flags " 835 "CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD " 836 "(0x10f00), and may not work correctly with given flags " 837 "0x%llx\n", flags); 838 } 839 840 ThreadContext* ctc; // child thread context 841 if ( ( ctc = process->findFreeContext() ) != NULL ) { 842 DPRINTF(SyscallVerbose, " Found unallocated thread context\n"); 843 844 ctc->clearArchRegs(); 845 846 // Arch-specific cloning code 847 #if THE_ISA == ALPHA_ISA or THE_ISA == X86_ISA 848 // Cloning the misc. regs for these archs is enough 849 TheISA::copyMiscRegs(tc, ctc); 850 #elif THE_ISA == SPARC_ISA 851 TheISA::copyRegs(tc, ctc); 852 853 // TODO: Explain what this code actually does :-) 854 ctc->setIntReg(NumIntArchRegs + 6, 0); 855 ctc->setIntReg(NumIntArchRegs + 4, 0); 856 ctc->setIntReg(NumIntArchRegs + 3, NWindows - 2); 857 ctc->setIntReg(NumIntArchRegs + 5, NWindows); 858 ctc->setMiscReg(MISCREG_CWP, 0); 859 ctc->setIntReg(NumIntArchRegs + 7, 0); 860 ctc->setMiscRegNoEffect(MISCREG_TL, 0); 861 ctc->setMiscReg(MISCREG_ASI, ASI_PRIMARY); 862 863 for (int y = 8; y < 32; y++) 864 ctc->setIntReg(y, tc->readIntReg(y)); 865 #elif THE_ISA == ARM_ISA 866 TheISA::copyRegs(tc, ctc); 867 #else 868 fatal("sys_clone is not implemented for this ISA\n"); 869 #endif 870 871 // Set up stack register 872 ctc->setIntReg(TheISA::StackPointerReg, newStack); 873 874 // Set up syscall return values in parent and child 875 ctc->setIntReg(ReturnValueReg, 0); // return value, child 876 877 // Alpha needs SyscallSuccessReg=0 in child 878 #if THE_ISA == ALPHA_ISA 879 ctc->setIntReg(TheISA::SyscallSuccessReg, 0); 880 #endif 881 882 // In SPARC/Linux, clone returns 0 on pseudo-return register if 883 // parent, non-zero if child 884 #if THE_ISA == SPARC_ISA 885 tc->setIntReg(TheISA::SyscallPseudoReturnReg, 0); 886 ctc->setIntReg(TheISA::SyscallPseudoReturnReg, 1); 887 #endif 888 889 ctc->pcState(tc->nextInstAddr()); 890 891 ctc->activate(); 892 893 // Should return nonzero child TID in parent's syscall return register, 894 // but for our pthread library any non-zero value will work 895 return 1; 896 } else { 897 fatal("Called sys_clone, but no unallocated thread contexts found!\n"); 898 return 0; 899 } 900} 901 902SyscallReturn 903accessFunc(SyscallDesc *desc, int callnum, LiveProcess *p, ThreadContext *tc, 904 int index) 905{ 906 string path; 907 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index))) 908 return -EFAULT; 909 910 // Adjust path for current working directory 911 path = p->fullPath(path); 912 913 mode_t mode = p->getSyscallArg(tc, index); 914 915 int result = access(path.c_str(), mode); 916 return (result == -1) ? -errno : result; 917} 918 919SyscallReturn 920accessFunc(SyscallDesc *desc, int callnum, LiveProcess *p, ThreadContext *tc) 921{ 922 return accessFunc(desc, callnum, p, tc, 0); 923} 924 925