syscall_emul.hh revision 13571
1/* 2 * Copyright (c) 2012-2013, 2015 ARM Limited 3 * Copyright (c) 2015 Advanced Micro Devices, Inc. 4 * All rights reserved 5 * 6 * The license below extends only to copyright in the software and shall 7 * not be construed as granting a license to any other intellectual 8 * property including but not limited to intellectual property relating 9 * to a hardware implementation of the functionality of the software 10 * licensed hereunder. You may use the software subject to the license 11 * terms below provided that you ensure that this notice is replicated 12 * unmodified and in its entirety in all distributions of the software, 13 * modified or unmodified, in source code or in binary form. 14 * 15 * Copyright (c) 2003-2005 The Regents of The University of Michigan 16 * All rights reserved. 17 * 18 * Redistribution and use in source and binary forms, with or without 19 * modification, are permitted provided that the following conditions are 20 * met: redistributions of source code must retain the above copyright 21 * notice, this list of conditions and the following disclaimer; 22 * redistributions in binary form must reproduce the above copyright 23 * notice, this list of conditions and the following disclaimer in the 24 * documentation and/or other materials provided with the distribution; 25 * neither the name of the copyright holders nor the names of its 26 * contributors may be used to endorse or promote products derived from 27 * this software without specific prior written permission. 28 * 29 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 30 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 31 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 32 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 33 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 34 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 35 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 36 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 37 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 38 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 39 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 40 * 41 * Authors: Steve Reinhardt 42 * Kevin Lim 43 */ 44 45#ifndef __SIM_SYSCALL_EMUL_HH__ 46#define __SIM_SYSCALL_EMUL_HH__ 47 48#if (defined(__APPLE__) || defined(__OpenBSD__) || \ 49 defined(__FreeBSD__) || defined(__CYGWIN__) || \ 50 defined(__NetBSD__)) 51#define NO_STAT64 1 52#else 53#define NO_STAT64 0 54#endif 55 56#if (defined(__APPLE__) || defined(__OpenBSD__) || \ 57 defined(__FreeBSD__) || defined(__NetBSD__)) 58#define NO_STATFS 1 59#else 60#define NO_STATFS 0 61#endif 62 63#if (defined(__APPLE__) || defined(__OpenBSD__) || \ 64 defined(__FreeBSD__) || defined(__NetBSD__)) 65#define NO_FALLOCATE 1 66#else 67#define NO_FALLOCATE 0 68#endif 69 70/// 71/// @file syscall_emul.hh 72/// 73/// This file defines objects used to emulate syscalls from the target 74/// application on the host machine. 75 76#ifdef __CYGWIN32__ 77#include <sys/fcntl.h> 78 79#endif 80#include <fcntl.h> 81#include <poll.h> 82#include <sys/mman.h> 83#include <sys/socket.h> 84#include <sys/stat.h> 85#if (NO_STATFS == 0) 86#include <sys/statfs.h> 87#else 88#include <sys/mount.h> 89#endif 90#include <sys/time.h> 91#include <sys/types.h> 92#include <sys/uio.h> 93#include <unistd.h> 94 95#include <cerrno> 96#include <memory> 97#include <string> 98 99#include "arch/generic/tlb.hh" 100#include "arch/utility.hh" 101#include "base/intmath.hh" 102#include "base/loader/object_file.hh" 103#include "base/logging.hh" 104#include "base/trace.hh" 105#include "base/types.hh" 106#include "config/the_isa.hh" 107#include "cpu/base.hh" 108#include "cpu/thread_context.hh" 109#include "mem/page_table.hh" 110#include "params/Process.hh" 111#include "sim/emul_driver.hh" 112#include "sim/futex_map.hh" 113#include "sim/process.hh" 114#include "sim/syscall_debug_macros.hh" 115#include "sim/syscall_desc.hh" 116#include "sim/syscall_emul_buf.hh" 117#include "sim/syscall_return.hh" 118 119////////////////////////////////////////////////////////////////////// 120// 121// The following emulation functions are generic enough that they 122// don't need to be recompiled for different emulated OS's. They are 123// defined in sim/syscall_emul.cc. 124// 125////////////////////////////////////////////////////////////////////// 126 127 128/// Handler for unimplemented syscalls that we haven't thought about. 129SyscallReturn unimplementedFunc(SyscallDesc *desc, int num, 130 Process *p, ThreadContext *tc); 131 132/// Handler for unimplemented syscalls that we never intend to 133/// implement (signal handling, etc.) and should not affect the correct 134/// behavior of the program. Print a warning only if the appropriate 135/// trace flag is enabled. Return success to the target program. 136SyscallReturn ignoreFunc(SyscallDesc *desc, int num, 137 Process *p, ThreadContext *tc); 138 139// Target fallocateFunc() handler. 140SyscallReturn fallocateFunc(SyscallDesc *desc, int num, 141 Process *p, ThreadContext *tc); 142 143/// Target exit() handler: terminate current context. 144SyscallReturn exitFunc(SyscallDesc *desc, int num, 145 Process *p, ThreadContext *tc); 146 147/// Target exit_group() handler: terminate simulation. (exit all threads) 148SyscallReturn exitGroupFunc(SyscallDesc *desc, int num, 149 Process *p, ThreadContext *tc); 150 151/// Target set_tid_address() handler. 152SyscallReturn setTidAddressFunc(SyscallDesc *desc, int num, 153 Process *p, ThreadContext *tc); 154 155/// Target getpagesize() handler. 156SyscallReturn getpagesizeFunc(SyscallDesc *desc, int num, 157 Process *p, ThreadContext *tc); 158 159/// Target brk() handler: set brk address. 160SyscallReturn brkFunc(SyscallDesc *desc, int num, 161 Process *p, ThreadContext *tc); 162 163/// Target close() handler. 164SyscallReturn closeFunc(SyscallDesc *desc, int num, 165 Process *p, ThreadContext *tc); 166 167/// Target lseek() handler. 168SyscallReturn lseekFunc(SyscallDesc *desc, int num, 169 Process *p, ThreadContext *tc); 170 171/// Target _llseek() handler. 172SyscallReturn _llseekFunc(SyscallDesc *desc, int num, 173 Process *p, ThreadContext *tc); 174 175/// Target munmap() handler. 176SyscallReturn munmapFunc(SyscallDesc *desc, int num, 177 Process *p, ThreadContext *tc); 178 179/// Target shutdown() handler. 180SyscallReturn shutdownFunc(SyscallDesc *desc, int num, 181 Process *p, ThreadContext *tc); 182 183/// Target gethostname() handler. 184SyscallReturn gethostnameFunc(SyscallDesc *desc, int num, 185 Process *p, ThreadContext *tc); 186 187/// Target getcwd() handler. 188SyscallReturn getcwdFunc(SyscallDesc *desc, int num, 189 Process *p, ThreadContext *tc); 190 191/// Target readlink() handler. 192SyscallReturn readlinkFunc(SyscallDesc *desc, int num, 193 Process *p, ThreadContext *tc, 194 int index = 0); 195SyscallReturn readlinkFunc(SyscallDesc *desc, int num, 196 Process *p, ThreadContext *tc); 197 198/// Target unlink() handler. 199SyscallReturn unlinkHelper(SyscallDesc *desc, int num, 200 Process *p, ThreadContext *tc, 201 int index); 202SyscallReturn unlinkFunc(SyscallDesc *desc, int num, 203 Process *p, ThreadContext *tc); 204 205/// Target link() handler 206SyscallReturn linkFunc(SyscallDesc *desc, int num, Process *p, 207 ThreadContext *tc); 208 209/// Target symlink() handler. 210SyscallReturn symlinkFunc(SyscallDesc *desc, int num, Process *p, 211 ThreadContext *tc); 212 213/// Target mkdir() handler. 214SyscallReturn mkdirFunc(SyscallDesc *desc, int num, 215 Process *p, ThreadContext *tc); 216 217/// Target mknod() handler. 218SyscallReturn mknodFunc(SyscallDesc *desc, int num, 219 Process *p, ThreadContext *tc); 220 221/// Target chdir() handler. 222SyscallReturn chdirFunc(SyscallDesc *desc, int num, 223 Process *p, ThreadContext *tc); 224 225// Target rmdir() handler. 226SyscallReturn rmdirFunc(SyscallDesc *desc, int num, 227 Process *p, ThreadContext *tc); 228 229/// Target rename() handler. 230SyscallReturn renameFunc(SyscallDesc *desc, int num, 231 Process *p, ThreadContext *tc); 232 233 234/// Target truncate() handler. 235SyscallReturn truncateFunc(SyscallDesc *desc, int num, 236 Process *p, ThreadContext *tc); 237 238 239/// Target ftruncate() handler. 240SyscallReturn ftruncateFunc(SyscallDesc *desc, int num, 241 Process *p, ThreadContext *tc); 242 243 244/// Target truncate64() handler. 245SyscallReturn truncate64Func(SyscallDesc *desc, int num, 246 Process *p, ThreadContext *tc); 247 248/// Target ftruncate64() handler. 249SyscallReturn ftruncate64Func(SyscallDesc *desc, int num, 250 Process *p, ThreadContext *tc); 251 252 253/// Target umask() handler. 254SyscallReturn umaskFunc(SyscallDesc *desc, int num, 255 Process *p, ThreadContext *tc); 256 257/// Target gettid() handler. 258SyscallReturn gettidFunc(SyscallDesc *desc, int num, 259 Process *p, ThreadContext *tc); 260 261/// Target chown() handler. 262SyscallReturn chownFunc(SyscallDesc *desc, int num, 263 Process *p, ThreadContext *tc); 264 265/// Target setpgid() handler. 266SyscallReturn setpgidFunc(SyscallDesc *desc, int num, 267 Process *p, ThreadContext *tc); 268 269/// Target fchown() handler. 270SyscallReturn fchownFunc(SyscallDesc *desc, int num, 271 Process *p, ThreadContext *tc); 272 273/// Target dup() handler. 274SyscallReturn dupFunc(SyscallDesc *desc, int num, 275 Process *process, ThreadContext *tc); 276 277/// Target dup2() handler. 278SyscallReturn dup2Func(SyscallDesc *desc, int num, 279 Process *process, ThreadContext *tc); 280 281/// Target fcntl() handler. 282SyscallReturn fcntlFunc(SyscallDesc *desc, int num, 283 Process *process, ThreadContext *tc); 284 285/// Target fcntl64() handler. 286SyscallReturn fcntl64Func(SyscallDesc *desc, int num, 287 Process *process, ThreadContext *tc); 288 289/// Target setuid() handler. 290SyscallReturn setuidFunc(SyscallDesc *desc, int num, 291 Process *p, ThreadContext *tc); 292 293/// Target pipe() handler. 294SyscallReturn pipeFunc(SyscallDesc *desc, int num, 295 Process *p, ThreadContext *tc); 296 297/// Internal pipe() handler. 298SyscallReturn pipeImpl(SyscallDesc *desc, int num, Process *p, 299 ThreadContext *tc, bool pseudoPipe); 300 301/// Target getpid() handler. 302SyscallReturn getpidFunc(SyscallDesc *desc, int num, 303 Process *p, ThreadContext *tc); 304 305// Target getpeername() handler. 306SyscallReturn getpeernameFunc(SyscallDesc *desc, int num, 307 Process *p, ThreadContext *tc); 308 309// Target bind() handler. 310SyscallReturn bindFunc(SyscallDesc *desc, int num, 311 Process *p, ThreadContext *tc); 312 313// Target listen() handler. 314SyscallReturn listenFunc(SyscallDesc *desc, int num, 315 Process *p, ThreadContext *tc); 316 317// Target connect() handler. 318SyscallReturn connectFunc(SyscallDesc *desc, int num, 319 Process *p, ThreadContext *tc); 320 321#if defined(SYS_getdents) 322// Target getdents() handler. 323SyscallReturn getdentsFunc(SyscallDesc *desc, int num, 324 Process *p, ThreadContext *tc); 325#endif 326 327#if defined(SYS_getdents64) 328// Target getdents() handler. 329SyscallReturn getdents64Func(SyscallDesc *desc, int num, 330 Process *p, ThreadContext *tc); 331#endif 332 333// Target sendto() handler. 334SyscallReturn sendtoFunc(SyscallDesc *desc, int num, 335 Process *p, ThreadContext *tc); 336 337// Target recvfrom() handler. 338SyscallReturn recvfromFunc(SyscallDesc *desc, int num, 339 Process *p, ThreadContext *tc); 340 341// Target recvmsg() handler. 342SyscallReturn recvmsgFunc(SyscallDesc *desc, int num, 343 Process *p, ThreadContext *tc); 344 345// Target sendmsg() handler. 346SyscallReturn sendmsgFunc(SyscallDesc *desc, int num, 347 Process *p, ThreadContext *tc); 348 349// Target getuid() handler. 350SyscallReturn getuidFunc(SyscallDesc *desc, int num, 351 Process *p, ThreadContext *tc); 352 353/// Target getgid() handler. 354SyscallReturn getgidFunc(SyscallDesc *desc, int num, 355 Process *p, ThreadContext *tc); 356 357/// Target getppid() handler. 358SyscallReturn getppidFunc(SyscallDesc *desc, int num, 359 Process *p, ThreadContext *tc); 360 361/// Target geteuid() handler. 362SyscallReturn geteuidFunc(SyscallDesc *desc, int num, 363 Process *p, ThreadContext *tc); 364 365/// Target getegid() handler. 366SyscallReturn getegidFunc(SyscallDesc *desc, int num, 367 Process *p, ThreadContext *tc); 368 369/// Target access() handler 370SyscallReturn accessFunc(SyscallDesc *desc, int num, 371 Process *p, ThreadContext *tc); 372SyscallReturn accessFunc(SyscallDesc *desc, int num, 373 Process *p, ThreadContext *tc, 374 int index); 375 376// Target getsockopt() handler. 377SyscallReturn getsockoptFunc(SyscallDesc *desc, int num, 378 Process *p, ThreadContext *tc); 379 380// Target setsockopt() handler. 381SyscallReturn setsockoptFunc(SyscallDesc *desc, int num, 382 Process *p, ThreadContext *tc); 383 384// Target getsockname() handler. 385SyscallReturn getsocknameFunc(SyscallDesc *desc, int num, 386 Process *p, ThreadContext *tc); 387 388/// Futex system call 389/// Implemented by Daniel Sanchez 390/// Used by printf's in multi-threaded apps 391template <class OS> 392SyscallReturn 393futexFunc(SyscallDesc *desc, int callnum, Process *process, 394 ThreadContext *tc) 395{ 396 using namespace std; 397 398 int index = 0; 399 Addr uaddr = process->getSyscallArg(tc, index); 400 int op = process->getSyscallArg(tc, index); 401 int val = process->getSyscallArg(tc, index); 402 403 /* 404 * Unsupported option that does not affect the correctness of the 405 * application. This is a performance optimization utilized by Linux. 406 */ 407 op &= ~OS::TGT_FUTEX_PRIVATE_FLAG; 408 409 FutexMap &futex_map = tc->getSystemPtr()->futexMap; 410 411 if (OS::TGT_FUTEX_WAIT == op) { 412 // Ensure futex system call accessed atomically. 413 BufferArg buf(uaddr, sizeof(int)); 414 buf.copyIn(tc->getMemProxy()); 415 int mem_val = *(int*)buf.bufferPtr(); 416 417 /* 418 * The value in memory at uaddr is not equal with the expected val 419 * (a different thread must have changed it before the system call was 420 * invoked). In this case, we need to throw an error. 421 */ 422 if (val != mem_val) 423 return -OS::TGT_EWOULDBLOCK; 424 425 futex_map.suspend(uaddr, process->tgid(), tc); 426 427 return 0; 428 } else if (OS::TGT_FUTEX_WAKE == op) { 429 return futex_map.wakeup(uaddr, process->tgid(), val); 430 } 431 432 warn("futex: op %d not implemented; ignoring.", op); 433 return -ENOSYS; 434} 435 436 437/// Pseudo Funcs - These functions use a different return convension, 438/// returning a second value in a register other than the normal return register 439SyscallReturn pipePseudoFunc(SyscallDesc *desc, int num, 440 Process *process, ThreadContext *tc); 441 442/// Target getpidPseudo() handler. 443SyscallReturn getpidPseudoFunc(SyscallDesc *desc, int num, 444 Process *p, ThreadContext *tc); 445 446/// Target getuidPseudo() handler. 447SyscallReturn getuidPseudoFunc(SyscallDesc *desc, int num, 448 Process *p, ThreadContext *tc); 449 450/// Target getgidPseudo() handler. 451SyscallReturn getgidPseudoFunc(SyscallDesc *desc, int num, 452 Process *p, ThreadContext *tc); 453 454 455/// A readable name for 1,000,000, for converting microseconds to seconds. 456const int one_million = 1000000; 457/// A readable name for 1,000,000,000, for converting nanoseconds to seconds. 458const int one_billion = 1000000000; 459 460/// Approximate seconds since the epoch (1/1/1970). About a billion, 461/// by my reckoning. We want to keep this a constant (not use the 462/// real-world time) to keep simulations repeatable. 463const unsigned seconds_since_epoch = 1000000000; 464 465/// Helper function to convert current elapsed time to seconds and 466/// microseconds. 467template <class T1, class T2> 468void 469getElapsedTimeMicro(T1 &sec, T2 &usec) 470{ 471 uint64_t elapsed_usecs = curTick() / SimClock::Int::us; 472 sec = elapsed_usecs / one_million; 473 usec = elapsed_usecs % one_million; 474} 475 476/// Helper function to convert current elapsed time to seconds and 477/// nanoseconds. 478template <class T1, class T2> 479void 480getElapsedTimeNano(T1 &sec, T2 &nsec) 481{ 482 uint64_t elapsed_nsecs = curTick() / SimClock::Int::ns; 483 sec = elapsed_nsecs / one_billion; 484 nsec = elapsed_nsecs % one_billion; 485} 486 487////////////////////////////////////////////////////////////////////// 488// 489// The following emulation functions are generic, but need to be 490// templated to account for differences in types, constants, etc. 491// 492////////////////////////////////////////////////////////////////////// 493 494 typedef struct statfs hst_statfs; 495#if NO_STAT64 496 typedef struct stat hst_stat; 497 typedef struct stat hst_stat64; 498#else 499 typedef struct stat hst_stat; 500 typedef struct stat64 hst_stat64; 501#endif 502 503//// Helper function to convert a host stat buffer to a target stat 504//// buffer. Also copies the target buffer out to the simulated 505//// memory space. Used by stat(), fstat(), and lstat(). 506 507template <typename target_stat, typename host_stat> 508void 509convertStatBuf(target_stat &tgt, host_stat *host, bool fakeTTY = false) 510{ 511 using namespace TheISA; 512 513 if (fakeTTY) 514 tgt->st_dev = 0xA; 515 else 516 tgt->st_dev = host->st_dev; 517 tgt->st_dev = TheISA::htog(tgt->st_dev); 518 tgt->st_ino = host->st_ino; 519 tgt->st_ino = TheISA::htog(tgt->st_ino); 520 tgt->st_mode = host->st_mode; 521 if (fakeTTY) { 522 // Claim to be a character device 523 tgt->st_mode &= ~S_IFMT; // Clear S_IFMT 524 tgt->st_mode |= S_IFCHR; // Set S_IFCHR 525 } 526 tgt->st_mode = TheISA::htog(tgt->st_mode); 527 tgt->st_nlink = host->st_nlink; 528 tgt->st_nlink = TheISA::htog(tgt->st_nlink); 529 tgt->st_uid = host->st_uid; 530 tgt->st_uid = TheISA::htog(tgt->st_uid); 531 tgt->st_gid = host->st_gid; 532 tgt->st_gid = TheISA::htog(tgt->st_gid); 533 if (fakeTTY) 534 tgt->st_rdev = 0x880d; 535 else 536 tgt->st_rdev = host->st_rdev; 537 tgt->st_rdev = TheISA::htog(tgt->st_rdev); 538 tgt->st_size = host->st_size; 539 tgt->st_size = TheISA::htog(tgt->st_size); 540 tgt->st_atimeX = host->st_atime; 541 tgt->st_atimeX = TheISA::htog(tgt->st_atimeX); 542 tgt->st_mtimeX = host->st_mtime; 543 tgt->st_mtimeX = TheISA::htog(tgt->st_mtimeX); 544 tgt->st_ctimeX = host->st_ctime; 545 tgt->st_ctimeX = TheISA::htog(tgt->st_ctimeX); 546 // Force the block size to be 8KB. This helps to ensure buffered io works 547 // consistently across different hosts. 548 tgt->st_blksize = 0x2000; 549 tgt->st_blksize = TheISA::htog(tgt->st_blksize); 550 tgt->st_blocks = host->st_blocks; 551 tgt->st_blocks = TheISA::htog(tgt->st_blocks); 552} 553 554// Same for stat64 555 556template <typename target_stat, typename host_stat64> 557void 558convertStat64Buf(target_stat &tgt, host_stat64 *host, bool fakeTTY = false) 559{ 560 using namespace TheISA; 561 562 convertStatBuf<target_stat, host_stat64>(tgt, host, fakeTTY); 563#if defined(STAT_HAVE_NSEC) 564 tgt->st_atime_nsec = host->st_atime_nsec; 565 tgt->st_atime_nsec = TheISA::htog(tgt->st_atime_nsec); 566 tgt->st_mtime_nsec = host->st_mtime_nsec; 567 tgt->st_mtime_nsec = TheISA::htog(tgt->st_mtime_nsec); 568 tgt->st_ctime_nsec = host->st_ctime_nsec; 569 tgt->st_ctime_nsec = TheISA::htog(tgt->st_ctime_nsec); 570#else 571 tgt->st_atime_nsec = 0; 572 tgt->st_mtime_nsec = 0; 573 tgt->st_ctime_nsec = 0; 574#endif 575} 576 577// Here are a couple of convenience functions 578template<class OS> 579void 580copyOutStatBuf(SETranslatingPortProxy &mem, Addr addr, 581 hst_stat *host, bool fakeTTY = false) 582{ 583 typedef TypedBufferArg<typename OS::tgt_stat> tgt_stat_buf; 584 tgt_stat_buf tgt(addr); 585 convertStatBuf<tgt_stat_buf, hst_stat>(tgt, host, fakeTTY); 586 tgt.copyOut(mem); 587} 588 589template<class OS> 590void 591copyOutStat64Buf(SETranslatingPortProxy &mem, Addr addr, 592 hst_stat64 *host, bool fakeTTY = false) 593{ 594 typedef TypedBufferArg<typename OS::tgt_stat64> tgt_stat_buf; 595 tgt_stat_buf tgt(addr); 596 convertStat64Buf<tgt_stat_buf, hst_stat64>(tgt, host, fakeTTY); 597 tgt.copyOut(mem); 598} 599 600template <class OS> 601void 602copyOutStatfsBuf(SETranslatingPortProxy &mem, Addr addr, 603 hst_statfs *host) 604{ 605 TypedBufferArg<typename OS::tgt_statfs> tgt(addr); 606 607 tgt->f_type = TheISA::htog(host->f_type); 608#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) 609 tgt->f_bsize = TheISA::htog(host->f_iosize); 610#else 611 tgt->f_bsize = TheISA::htog(host->f_bsize); 612#endif 613 tgt->f_blocks = TheISA::htog(host->f_blocks); 614 tgt->f_bfree = TheISA::htog(host->f_bfree); 615 tgt->f_bavail = TheISA::htog(host->f_bavail); 616 tgt->f_files = TheISA::htog(host->f_files); 617 tgt->f_ffree = TheISA::htog(host->f_ffree); 618 memcpy(&tgt->f_fsid, &host->f_fsid, sizeof(host->f_fsid)); 619#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) 620 tgt->f_namelen = TheISA::htog(host->f_namemax); 621 tgt->f_frsize = TheISA::htog(host->f_bsize); 622#elif defined(__APPLE__) 623 tgt->f_namelen = 0; 624 tgt->f_frsize = 0; 625#else 626 tgt->f_namelen = TheISA::htog(host->f_namelen); 627 tgt->f_frsize = TheISA::htog(host->f_frsize); 628#endif 629#if defined(__linux__) 630 memcpy(&tgt->f_spare, &host->f_spare, sizeof(host->f_spare)); 631#else 632 /* 633 * The fields are different sizes per OS. Don't bother with 634 * f_spare or f_reserved on non-Linux for now. 635 */ 636 memset(&tgt->f_spare, 0, sizeof(tgt->f_spare)); 637#endif 638 639 tgt.copyOut(mem); 640} 641 642/// Target ioctl() handler. For the most part, programs call ioctl() 643/// only to find out if their stdout is a tty, to determine whether to 644/// do line or block buffering. We always claim that output fds are 645/// not TTYs to provide repeatable results. 646template <class OS> 647SyscallReturn 648ioctlFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc) 649{ 650 int index = 0; 651 int tgt_fd = p->getSyscallArg(tc, index); 652 unsigned req = p->getSyscallArg(tc, index); 653 654 DPRINTF(SyscallVerbose, "ioctl(%d, 0x%x, ...)\n", tgt_fd, req); 655 656 if (OS::isTtyReq(req)) 657 return -ENOTTY; 658 659 auto dfdp = std::dynamic_pointer_cast<DeviceFDEntry>((*p->fds)[tgt_fd]); 660 if (!dfdp) 661 return -EBADF; 662 663 /** 664 * If the driver is valid, issue the ioctl through it. Otherwise, 665 * there's an implicit assumption that the device is a TTY type and we 666 * return that we do not have a valid TTY. 667 */ 668 EmulatedDriver *emul_driver = dfdp->getDriver(); 669 if (emul_driver) 670 return emul_driver->ioctl(p, tc, req); 671 672 /** 673 * For lack of a better return code, return ENOTTY. Ideally, we should 674 * return something better here, but at least we issue the warning. 675 */ 676 warn("Unsupported ioctl call (return ENOTTY): ioctl(%d, 0x%x, ...) @ \n", 677 tgt_fd, req, tc->pcState()); 678 return -ENOTTY; 679} 680 681template <class OS> 682SyscallReturn 683openImpl(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc, 684 bool isopenat) 685{ 686 int index = 0; 687 int tgt_dirfd = -1; 688 689 /** 690 * If using the openat variant, read in the target directory file 691 * descriptor from the simulated process. 692 */ 693 if (isopenat) 694 tgt_dirfd = p->getSyscallArg(tc, index); 695 696 /** 697 * Retrieve the simulated process' memory proxy and then read in the path 698 * string from that memory space into the host's working memory space. 699 */ 700 std::string path; 701 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index))) 702 return -EFAULT; 703 704#ifdef __CYGWIN32__ 705 int host_flags = O_BINARY; 706#else 707 int host_flags = 0; 708#endif 709 /** 710 * Translate target flags into host flags. Flags exist which are not 711 * ported between architectures which can cause check failures. 712 */ 713 int tgt_flags = p->getSyscallArg(tc, index); 714 for (int i = 0; i < OS::NUM_OPEN_FLAGS; i++) { 715 if (tgt_flags & OS::openFlagTable[i].tgtFlag) { 716 tgt_flags &= ~OS::openFlagTable[i].tgtFlag; 717 host_flags |= OS::openFlagTable[i].hostFlag; 718 } 719 } 720 if (tgt_flags) { 721 warn("open%s: cannot decode flags 0x%x", 722 isopenat ? "at" : "", tgt_flags); 723 } 724#ifdef __CYGWIN32__ 725 host_flags |= O_BINARY; 726#endif 727 728 int mode = p->getSyscallArg(tc, index); 729 730 /** 731 * If the simulated process called open or openat with AT_FDCWD specified, 732 * take the current working directory value which was passed into the 733 * process class as a Python parameter and append the current path to 734 * create a full path. 735 * Otherwise, openat with a valid target directory file descriptor has 736 * been called. If the path option, which was passed in as a parameter, 737 * is not absolute, retrieve the directory file descriptor's path and 738 * prepend it to the path passed in as a parameter. 739 * In every case, we should have a full path (which is relevant to the 740 * host) to work with after this block has been passed. 741 */ 742 if (!isopenat || (isopenat && tgt_dirfd == OS::TGT_AT_FDCWD)) { 743 path = p->fullPath(path); 744 } else if (!startswith(path, "/")) { 745 std::shared_ptr<FDEntry> fdep = ((*p->fds)[tgt_dirfd]); 746 auto ffdp = std::dynamic_pointer_cast<FileFDEntry>(fdep); 747 if (!ffdp) 748 return -EBADF; 749 path.insert(0, ffdp->getFileName() + "/"); 750 } 751 752 /** 753 * Since this is an emulated environment, we create pseudo file 754 * descriptors for device requests that have been registered with 755 * the process class through Python; this allows us to create a file 756 * descriptor for subsequent ioctl or mmap calls. 757 */ 758 if (startswith(path, "/dev/")) { 759 std::string filename = path.substr(strlen("/dev/")); 760 EmulatedDriver *drv = p->findDriver(filename); 761 if (drv) { 762 DPRINTF_SYSCALL(Verbose, "open%s: passing call to " 763 "driver open with path[%s]\n", 764 isopenat ? "at" : "", path.c_str()); 765 return drv->open(p, tc, mode, host_flags); 766 } 767 /** 768 * Fall through here for pass through to host devices, such 769 * as /dev/zero 770 */ 771 } 772 773 /** 774 * Some special paths and files cannot be called on the host and need 775 * to be handled as special cases inside the simulator. 776 * If the full path that was created above does not match any of the 777 * special cases, pass it through to the open call on the host to let 778 * the host open the file on our behalf. 779 * If the host cannot open the file, return the host's error code back 780 * through the system call to the simulated process. 781 */ 782 int sim_fd = -1; 783 std::vector<std::string> special_paths = 784 { "/proc/", "/system/", "/sys/", "/platform/", "/etc/passwd" }; 785 for (auto entry : special_paths) { 786 if (startswith(path, entry)) 787 sim_fd = OS::openSpecialFile(path, p, tc); 788 } 789 if (sim_fd == -1) { 790 sim_fd = open(path.c_str(), host_flags, mode); 791 } 792 if (sim_fd == -1) { 793 int local = -errno; 794 DPRINTF_SYSCALL(Verbose, "open%s: failed -> path:%s\n", 795 isopenat ? "at" : "", path.c_str()); 796 return local; 797 } 798 799 /** 800 * The file was opened successfully and needs to be recorded in the 801 * process' file descriptor array so that it can be retrieved later. 802 * The target file descriptor that is chosen will be the lowest unused 803 * file descriptor. 804 * Return the indirect target file descriptor back to the simulated 805 * process to act as a handle for the opened file. 806 */ 807 auto ffdp = std::make_shared<FileFDEntry>(sim_fd, host_flags, path, 0); 808 int tgt_fd = p->fds->allocFD(ffdp); 809 DPRINTF_SYSCALL(Verbose, "open%s: sim_fd[%d], target_fd[%d] -> path:%s\n", 810 isopenat ? "at" : "", sim_fd, tgt_fd, path.c_str()); 811 return tgt_fd; 812} 813 814/// Target open() handler. 815template <class OS> 816SyscallReturn 817openFunc(SyscallDesc *desc, int callnum, Process *process, 818 ThreadContext *tc) 819{ 820 return openImpl<OS>(desc, callnum, process, tc, false); 821} 822 823/// Target openat() handler. 824template <class OS> 825SyscallReturn 826openatFunc(SyscallDesc *desc, int callnum, Process *process, 827 ThreadContext *tc) 828{ 829 return openImpl<OS>(desc, callnum, process, tc, true); 830} 831 832/// Target unlinkat() handler. 833template <class OS> 834SyscallReturn 835unlinkatFunc(SyscallDesc *desc, int callnum, Process *process, 836 ThreadContext *tc) 837{ 838 int index = 0; 839 int dirfd = process->getSyscallArg(tc, index); 840 if (dirfd != OS::TGT_AT_FDCWD) 841 warn("unlinkat: first argument not AT_FDCWD; unlikely to work"); 842 843 return unlinkHelper(desc, callnum, process, tc, 1); 844} 845 846/// Target facessat() handler 847template <class OS> 848SyscallReturn 849faccessatFunc(SyscallDesc *desc, int callnum, Process *process, 850 ThreadContext *tc) 851{ 852 int index = 0; 853 int dirfd = process->getSyscallArg(tc, index); 854 if (dirfd != OS::TGT_AT_FDCWD) 855 warn("faccessat: first argument not AT_FDCWD; unlikely to work"); 856 return accessFunc(desc, callnum, process, tc, 1); 857} 858 859/// Target readlinkat() handler 860template <class OS> 861SyscallReturn 862readlinkatFunc(SyscallDesc *desc, int callnum, Process *process, 863 ThreadContext *tc) 864{ 865 int index = 0; 866 int dirfd = process->getSyscallArg(tc, index); 867 if (dirfd != OS::TGT_AT_FDCWD) 868 warn("openat: first argument not AT_FDCWD; unlikely to work"); 869 return readlinkFunc(desc, callnum, process, tc, 1); 870} 871 872/// Target renameat() handler. 873template <class OS> 874SyscallReturn 875renameatFunc(SyscallDesc *desc, int callnum, Process *process, 876 ThreadContext *tc) 877{ 878 int index = 0; 879 880 int olddirfd = process->getSyscallArg(tc, index); 881 if (olddirfd != OS::TGT_AT_FDCWD) 882 warn("renameat: first argument not AT_FDCWD; unlikely to work"); 883 884 std::string old_name; 885 886 if (!tc->getMemProxy().tryReadString(old_name, 887 process->getSyscallArg(tc, index))) 888 return -EFAULT; 889 890 int newdirfd = process->getSyscallArg(tc, index); 891 if (newdirfd != OS::TGT_AT_FDCWD) 892 warn("renameat: third argument not AT_FDCWD; unlikely to work"); 893 894 std::string new_name; 895 896 if (!tc->getMemProxy().tryReadString(new_name, 897 process->getSyscallArg(tc, index))) 898 return -EFAULT; 899 900 // Adjust path for current working directory 901 old_name = process->fullPath(old_name); 902 new_name = process->fullPath(new_name); 903 904 int result = rename(old_name.c_str(), new_name.c_str()); 905 return (result == -1) ? -errno : result; 906} 907 908/// Target sysinfo() handler. 909template <class OS> 910SyscallReturn 911sysinfoFunc(SyscallDesc *desc, int callnum, Process *process, 912 ThreadContext *tc) 913{ 914 915 int index = 0; 916 TypedBufferArg<typename OS::tgt_sysinfo> 917 sysinfo(process->getSyscallArg(tc, index)); 918 919 sysinfo->uptime = seconds_since_epoch; 920 sysinfo->totalram = process->system->memSize(); 921 sysinfo->mem_unit = 1; 922 923 sysinfo.copyOut(tc->getMemProxy()); 924 925 return 0; 926} 927 928/// Target chmod() handler. 929template <class OS> 930SyscallReturn 931chmodFunc(SyscallDesc *desc, int callnum, Process *process, 932 ThreadContext *tc) 933{ 934 std::string path; 935 936 int index = 0; 937 if (!tc->getMemProxy().tryReadString(path, 938 process->getSyscallArg(tc, index))) { 939 return -EFAULT; 940 } 941 942 uint32_t mode = process->getSyscallArg(tc, index); 943 mode_t hostMode = 0; 944 945 // XXX translate mode flags via OS::something??? 946 hostMode = mode; 947 948 // Adjust path for current working directory 949 path = process->fullPath(path); 950 951 // do the chmod 952 int result = chmod(path.c_str(), hostMode); 953 if (result < 0) 954 return -errno; 955 956 return 0; 957} 958 959template <class OS> 960SyscallReturn 961pollFunc(SyscallDesc *desc, int num, Process *p, ThreadContext *tc) 962{ 963 int index = 0; 964 Addr fdsPtr = p->getSyscallArg(tc, index); 965 int nfds = p->getSyscallArg(tc, index); 966 int tmout = p->getSyscallArg(tc, index); 967 968 BufferArg fdsBuf(fdsPtr, sizeof(struct pollfd) * nfds); 969 fdsBuf.copyIn(tc->getMemProxy()); 970 971 /** 972 * Record the target file descriptors in a local variable. We need to 973 * replace them with host file descriptors but we need a temporary copy 974 * for later. Afterwards, replace each target file descriptor in the 975 * poll_fd array with its host_fd. 976 */ 977 int temp_tgt_fds[nfds]; 978 for (index = 0; index < nfds; index++) { 979 temp_tgt_fds[index] = ((struct pollfd *)fdsBuf.bufferPtr())[index].fd; 980 auto tgt_fd = temp_tgt_fds[index]; 981 auto hbfdp = std::dynamic_pointer_cast<HBFDEntry>((*p->fds)[tgt_fd]); 982 if (!hbfdp) 983 return -EBADF; 984 auto host_fd = hbfdp->getSimFD(); 985 ((struct pollfd *)fdsBuf.bufferPtr())[index].fd = host_fd; 986 } 987 988 /** 989 * We cannot allow an infinite poll to occur or it will inevitably cause 990 * a deadlock in the gem5 simulator with clone. We must pass in tmout with 991 * a non-negative value, however it also makes no sense to poll on the 992 * underlying host for any other time than tmout a zero timeout. 993 */ 994 int status; 995 if (tmout < 0) { 996 status = poll((struct pollfd *)fdsBuf.bufferPtr(), nfds, 0); 997 if (status == 0) { 998 /** 999 * If blocking indefinitely, check the signal list to see if a 1000 * signal would break the poll out of the retry cycle and try 1001 * to return the signal interrupt instead. 1002 */ 1003 System *sysh = tc->getSystemPtr(); 1004 std::list<BasicSignal>::iterator it; 1005 for (it=sysh->signalList.begin(); it!=sysh->signalList.end(); it++) 1006 if (it->receiver == p) 1007 return -EINTR; 1008 return SyscallReturn::retry(); 1009 } 1010 } else 1011 status = poll((struct pollfd *)fdsBuf.bufferPtr(), nfds, 0); 1012 1013 if (status == -1) 1014 return -errno; 1015 1016 /** 1017 * Replace each host_fd in the returned poll_fd array with its original 1018 * target file descriptor. 1019 */ 1020 for (index = 0; index < nfds; index++) { 1021 auto tgt_fd = temp_tgt_fds[index]; 1022 ((struct pollfd *)fdsBuf.bufferPtr())[index].fd = tgt_fd; 1023 } 1024 1025 /** 1026 * Copy out the pollfd struct because the host may have updated fields 1027 * in the structure. 1028 */ 1029 fdsBuf.copyOut(tc->getMemProxy()); 1030 1031 return status; 1032} 1033 1034/// Target fchmod() handler. 1035template <class OS> 1036SyscallReturn 1037fchmodFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc) 1038{ 1039 int index = 0; 1040 int tgt_fd = p->getSyscallArg(tc, index); 1041 uint32_t mode = p->getSyscallArg(tc, index); 1042 1043 auto ffdp = std::dynamic_pointer_cast<FileFDEntry>((*p->fds)[tgt_fd]); 1044 if (!ffdp) 1045 return -EBADF; 1046 int sim_fd = ffdp->getSimFD(); 1047 1048 mode_t hostMode = mode; 1049 1050 int result = fchmod(sim_fd, hostMode); 1051 1052 return (result < 0) ? -errno : 0; 1053} 1054 1055/// Target mremap() handler. 1056template <class OS> 1057SyscallReturn 1058mremapFunc(SyscallDesc *desc, int callnum, Process *process, ThreadContext *tc) 1059{ 1060 int index = 0; 1061 Addr start = process->getSyscallArg(tc, index); 1062 uint64_t old_length = process->getSyscallArg(tc, index); 1063 uint64_t new_length = process->getSyscallArg(tc, index); 1064 uint64_t flags = process->getSyscallArg(tc, index); 1065 uint64_t provided_address = 0; 1066 bool use_provided_address = flags & OS::TGT_MREMAP_FIXED; 1067 1068 if (use_provided_address) 1069 provided_address = process->getSyscallArg(tc, index); 1070 1071 if ((start % TheISA::PageBytes != 0) || 1072 (provided_address % TheISA::PageBytes != 0)) { 1073 warn("mremap failing: arguments not page aligned"); 1074 return -EINVAL; 1075 } 1076 1077 new_length = roundUp(new_length, TheISA::PageBytes); 1078 1079 if (new_length > old_length) { 1080 std::shared_ptr<MemState> mem_state = process->memState; 1081 Addr mmap_end = mem_state->getMmapEnd(); 1082 1083 if ((start + old_length) == mmap_end && 1084 (!use_provided_address || provided_address == start)) { 1085 // This case cannot occur when growing downward, as 1086 // start is greater than or equal to mmap_end. 1087 uint64_t diff = new_length - old_length; 1088 process->allocateMem(mmap_end, diff); 1089 mem_state->setMmapEnd(mmap_end + diff); 1090 return start; 1091 } else { 1092 if (!use_provided_address && !(flags & OS::TGT_MREMAP_MAYMOVE)) { 1093 warn("can't remap here and MREMAP_MAYMOVE flag not set\n"); 1094 return -ENOMEM; 1095 } else { 1096 uint64_t new_start = provided_address; 1097 if (!use_provided_address) { 1098 new_start = process->mmapGrowsDown() ? 1099 mmap_end - new_length : mmap_end; 1100 mmap_end = process->mmapGrowsDown() ? 1101 new_start : mmap_end + new_length; 1102 mem_state->setMmapEnd(mmap_end); 1103 } 1104 1105 process->pTable->remap(start, old_length, new_start); 1106 warn("mremapping to new vaddr %08p-%08p, adding %d\n", 1107 new_start, new_start + new_length, 1108 new_length - old_length); 1109 // add on the remaining unallocated pages 1110 process->allocateMem(new_start + old_length, 1111 new_length - old_length, 1112 use_provided_address /* clobber */); 1113 if (use_provided_address && 1114 ((new_start + new_length > mem_state->getMmapEnd() && 1115 !process->mmapGrowsDown()) || 1116 (new_start < mem_state->getMmapEnd() && 1117 process->mmapGrowsDown()))) { 1118 // something fishy going on here, at least notify the user 1119 // @todo: increase mmap_end? 1120 warn("mmap region limit exceeded with MREMAP_FIXED\n"); 1121 } 1122 warn("returning %08p as start\n", new_start); 1123 return new_start; 1124 } 1125 } 1126 } else { 1127 if (use_provided_address && provided_address != start) 1128 process->pTable->remap(start, new_length, provided_address); 1129 process->pTable->unmap(start + new_length, old_length - new_length); 1130 return use_provided_address ? provided_address : start; 1131 } 1132} 1133 1134/// Target stat() handler. 1135template <class OS> 1136SyscallReturn 1137statFunc(SyscallDesc *desc, int callnum, Process *process, 1138 ThreadContext *tc) 1139{ 1140 std::string path; 1141 1142 int index = 0; 1143 if (!tc->getMemProxy().tryReadString(path, 1144 process->getSyscallArg(tc, index))) { 1145 return -EFAULT; 1146 } 1147 Addr bufPtr = process->getSyscallArg(tc, index); 1148 1149 // Adjust path for current working directory 1150 path = process->fullPath(path); 1151 1152 struct stat hostBuf; 1153 int result = stat(path.c_str(), &hostBuf); 1154 1155 if (result < 0) 1156 return -errno; 1157 1158 copyOutStatBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf); 1159 1160 return 0; 1161} 1162 1163 1164/// Target stat64() handler. 1165template <class OS> 1166SyscallReturn 1167stat64Func(SyscallDesc *desc, int callnum, Process *process, 1168 ThreadContext *tc) 1169{ 1170 std::string path; 1171 1172 int index = 0; 1173 if (!tc->getMemProxy().tryReadString(path, 1174 process->getSyscallArg(tc, index))) 1175 return -EFAULT; 1176 Addr bufPtr = process->getSyscallArg(tc, index); 1177 1178 // Adjust path for current working directory 1179 path = process->fullPath(path); 1180 1181#if NO_STAT64 1182 struct stat hostBuf; 1183 int result = stat(path.c_str(), &hostBuf); 1184#else 1185 struct stat64 hostBuf; 1186 int result = stat64(path.c_str(), &hostBuf); 1187#endif 1188 1189 if (result < 0) 1190 return -errno; 1191 1192 copyOutStat64Buf<OS>(tc->getMemProxy(), bufPtr, &hostBuf); 1193 1194 return 0; 1195} 1196 1197 1198/// Target fstatat64() handler. 1199template <class OS> 1200SyscallReturn 1201fstatat64Func(SyscallDesc *desc, int callnum, Process *process, 1202 ThreadContext *tc) 1203{ 1204 int index = 0; 1205 int dirfd = process->getSyscallArg(tc, index); 1206 if (dirfd != OS::TGT_AT_FDCWD) 1207 warn("fstatat64: first argument not AT_FDCWD; unlikely to work"); 1208 1209 std::string path; 1210 if (!tc->getMemProxy().tryReadString(path, 1211 process->getSyscallArg(tc, index))) 1212 return -EFAULT; 1213 Addr bufPtr = process->getSyscallArg(tc, index); 1214 1215 // Adjust path for current working directory 1216 path = process->fullPath(path); 1217 1218#if NO_STAT64 1219 struct stat hostBuf; 1220 int result = stat(path.c_str(), &hostBuf); 1221#else 1222 struct stat64 hostBuf; 1223 int result = stat64(path.c_str(), &hostBuf); 1224#endif 1225 1226 if (result < 0) 1227 return -errno; 1228 1229 copyOutStat64Buf<OS>(tc->getMemProxy(), bufPtr, &hostBuf); 1230 1231 return 0; 1232} 1233 1234 1235/// Target fstat64() handler. 1236template <class OS> 1237SyscallReturn 1238fstat64Func(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc) 1239{ 1240 int index = 0; 1241 int tgt_fd = p->getSyscallArg(tc, index); 1242 Addr bufPtr = p->getSyscallArg(tc, index); 1243 1244 auto ffdp = std::dynamic_pointer_cast<FileFDEntry>((*p->fds)[tgt_fd]); 1245 if (!ffdp) 1246 return -EBADF; 1247 int sim_fd = ffdp->getSimFD(); 1248 1249#if NO_STAT64 1250 struct stat hostBuf; 1251 int result = fstat(sim_fd, &hostBuf); 1252#else 1253 struct stat64 hostBuf; 1254 int result = fstat64(sim_fd, &hostBuf); 1255#endif 1256 1257 if (result < 0) 1258 return -errno; 1259 1260 copyOutStat64Buf<OS>(tc->getMemProxy(), bufPtr, &hostBuf, (sim_fd == 1)); 1261 1262 return 0; 1263} 1264 1265 1266/// Target lstat() handler. 1267template <class OS> 1268SyscallReturn 1269lstatFunc(SyscallDesc *desc, int callnum, Process *process, 1270 ThreadContext *tc) 1271{ 1272 std::string path; 1273 1274 int index = 0; 1275 if (!tc->getMemProxy().tryReadString(path, 1276 process->getSyscallArg(tc, index))) { 1277 return -EFAULT; 1278 } 1279 Addr bufPtr = process->getSyscallArg(tc, index); 1280 1281 // Adjust path for current working directory 1282 path = process->fullPath(path); 1283 1284 struct stat hostBuf; 1285 int result = lstat(path.c_str(), &hostBuf); 1286 1287 if (result < 0) 1288 return -errno; 1289 1290 copyOutStatBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf); 1291 1292 return 0; 1293} 1294 1295/// Target lstat64() handler. 1296template <class OS> 1297SyscallReturn 1298lstat64Func(SyscallDesc *desc, int callnum, Process *process, 1299 ThreadContext *tc) 1300{ 1301 std::string path; 1302 1303 int index = 0; 1304 if (!tc->getMemProxy().tryReadString(path, 1305 process->getSyscallArg(tc, index))) { 1306 return -EFAULT; 1307 } 1308 Addr bufPtr = process->getSyscallArg(tc, index); 1309 1310 // Adjust path for current working directory 1311 path = process->fullPath(path); 1312 1313#if NO_STAT64 1314 struct stat hostBuf; 1315 int result = lstat(path.c_str(), &hostBuf); 1316#else 1317 struct stat64 hostBuf; 1318 int result = lstat64(path.c_str(), &hostBuf); 1319#endif 1320 1321 if (result < 0) 1322 return -errno; 1323 1324 copyOutStat64Buf<OS>(tc->getMemProxy(), bufPtr, &hostBuf); 1325 1326 return 0; 1327} 1328 1329/// Target fstat() handler. 1330template <class OS> 1331SyscallReturn 1332fstatFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc) 1333{ 1334 int index = 0; 1335 int tgt_fd = p->getSyscallArg(tc, index); 1336 Addr bufPtr = p->getSyscallArg(tc, index); 1337 1338 DPRINTF_SYSCALL(Verbose, "fstat(%d, ...)\n", tgt_fd); 1339 1340 auto ffdp = std::dynamic_pointer_cast<FileFDEntry>((*p->fds)[tgt_fd]); 1341 if (!ffdp) 1342 return -EBADF; 1343 int sim_fd = ffdp->getSimFD(); 1344 1345 struct stat hostBuf; 1346 int result = fstat(sim_fd, &hostBuf); 1347 1348 if (result < 0) 1349 return -errno; 1350 1351 copyOutStatBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf, (sim_fd == 1)); 1352 1353 return 0; 1354} 1355 1356/// Target statfs() handler. 1357template <class OS> 1358SyscallReturn 1359statfsFunc(SyscallDesc *desc, int callnum, Process *process, 1360 ThreadContext *tc) 1361{ 1362#if NO_STATFS 1363 warn("Host OS cannot support calls to statfs. Ignoring syscall"); 1364#else 1365 std::string path; 1366 1367 int index = 0; 1368 if (!tc->getMemProxy().tryReadString(path, 1369 process->getSyscallArg(tc, index))) { 1370 return -EFAULT; 1371 } 1372 Addr bufPtr = process->getSyscallArg(tc, index); 1373 1374 // Adjust path for current working directory 1375 path = process->fullPath(path); 1376 1377 struct statfs hostBuf; 1378 int result = statfs(path.c_str(), &hostBuf); 1379 1380 if (result < 0) 1381 return -errno; 1382 1383 copyOutStatfsBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf); 1384#endif 1385 return 0; 1386} 1387 1388template <class OS> 1389SyscallReturn 1390cloneFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc) 1391{ 1392 int index = 0; 1393 1394 RegVal flags = p->getSyscallArg(tc, index); 1395 RegVal newStack = p->getSyscallArg(tc, index); 1396 Addr ptidPtr = p->getSyscallArg(tc, index); 1397 1398#if THE_ISA == RISCV_ISA or THE_ISA == ARM_ISA 1399 /** 1400 * Linux sets CLONE_BACKWARDS flag for RISC-V and Arm. 1401 * The flag defines the list of clone() arguments in the following 1402 * order: flags -> newStack -> ptidPtr -> tlsPtr -> ctidPtr 1403 */ 1404 Addr tlsPtr = p->getSyscallArg(tc, index); 1405 Addr ctidPtr = p->getSyscallArg(tc, index); 1406#else 1407 Addr ctidPtr = p->getSyscallArg(tc, index); 1408 Addr tlsPtr = p->getSyscallArg(tc, index); 1409#endif 1410 1411 if (((flags & OS::TGT_CLONE_SIGHAND)&& !(flags & OS::TGT_CLONE_VM)) || 1412 ((flags & OS::TGT_CLONE_THREAD) && !(flags & OS::TGT_CLONE_SIGHAND)) || 1413 ((flags & OS::TGT_CLONE_FS) && (flags & OS::TGT_CLONE_NEWNS)) || 1414 ((flags & OS::TGT_CLONE_NEWIPC) && (flags & OS::TGT_CLONE_SYSVSEM)) || 1415 ((flags & OS::TGT_CLONE_NEWPID) && (flags & OS::TGT_CLONE_THREAD)) || 1416 ((flags & OS::TGT_CLONE_VM) && !(newStack))) 1417 return -EINVAL; 1418 1419 ThreadContext *ctc; 1420 if (!(ctc = p->findFreeContext())) 1421 fatal("clone: no spare thread context in system"); 1422 1423 /** 1424 * Note that ProcessParams is generated by swig and there are no other 1425 * examples of how to create anything but this default constructor. The 1426 * fields are manually initialized instead of passing parameters to the 1427 * constructor. 1428 */ 1429 ProcessParams *pp = new ProcessParams(); 1430 pp->executable.assign(*(new std::string(p->progName()))); 1431 pp->cmd.push_back(*(new std::string(p->progName()))); 1432 pp->system = p->system; 1433 pp->cwd.assign(p->getcwd()); 1434 pp->input.assign("stdin"); 1435 pp->output.assign("stdout"); 1436 pp->errout.assign("stderr"); 1437 pp->uid = p->uid(); 1438 pp->euid = p->euid(); 1439 pp->gid = p->gid(); 1440 pp->egid = p->egid(); 1441 1442 /* Find the first free PID that's less than the maximum */ 1443 std::set<int> const& pids = p->system->PIDs; 1444 int temp_pid = *pids.begin(); 1445 do { 1446 temp_pid++; 1447 } while (pids.find(temp_pid) != pids.end()); 1448 if (temp_pid >= System::maxPID) 1449 fatal("temp_pid is too large: %d", temp_pid); 1450 1451 pp->pid = temp_pid; 1452 pp->ppid = (flags & OS::TGT_CLONE_THREAD) ? p->ppid() : p->pid(); 1453 Process *cp = pp->create(); 1454 delete pp; 1455 1456 Process *owner = ctc->getProcessPtr(); 1457 ctc->setProcessPtr(cp); 1458 cp->assignThreadContext(ctc->contextId()); 1459 owner->revokeThreadContext(ctc->contextId()); 1460 1461 if (flags & OS::TGT_CLONE_PARENT_SETTID) { 1462 BufferArg ptidBuf(ptidPtr, sizeof(long)); 1463 long *ptid = (long *)ptidBuf.bufferPtr(); 1464 *ptid = cp->pid(); 1465 ptidBuf.copyOut(tc->getMemProxy()); 1466 } 1467 1468 cp->initState(); 1469 p->clone(tc, ctc, cp, flags); 1470 1471 if (flags & OS::TGT_CLONE_THREAD) { 1472 delete cp->sigchld; 1473 cp->sigchld = p->sigchld; 1474 } else if (flags & OS::TGT_SIGCHLD) { 1475 *cp->sigchld = true; 1476 } 1477 1478 if (flags & OS::TGT_CLONE_CHILD_SETTID) { 1479 BufferArg ctidBuf(ctidPtr, sizeof(long)); 1480 long *ctid = (long *)ctidBuf.bufferPtr(); 1481 *ctid = cp->pid(); 1482 ctidBuf.copyOut(ctc->getMemProxy()); 1483 } 1484 1485 if (flags & OS::TGT_CLONE_CHILD_CLEARTID) 1486 cp->childClearTID = (uint64_t)ctidPtr; 1487 1488 ctc->clearArchRegs(); 1489 1490 OS::archClone(flags, p, cp, tc, ctc, newStack, tlsPtr); 1491 1492 cp->setSyscallReturn(ctc, 0); 1493 1494#if THE_ISA == ALPHA_ISA 1495 ctc->setIntReg(TheISA::SyscallSuccessReg, 0); 1496#elif THE_ISA == SPARC_ISA 1497 tc->setIntReg(TheISA::SyscallPseudoReturnReg, 0); 1498 ctc->setIntReg(TheISA::SyscallPseudoReturnReg, 1); 1499#endif 1500 1501 TheISA::PCState cpc = tc->pcState(); 1502 cpc.advance(); 1503 ctc->pcState(cpc); 1504 ctc->activate(); 1505 1506 return cp->pid(); 1507} 1508 1509/// Target fstatfs() handler. 1510template <class OS> 1511SyscallReturn 1512fstatfsFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc) 1513{ 1514 int index = 0; 1515 int tgt_fd = p->getSyscallArg(tc, index); 1516 Addr bufPtr = p->getSyscallArg(tc, index); 1517 1518 auto ffdp = std::dynamic_pointer_cast<FileFDEntry>((*p->fds)[tgt_fd]); 1519 if (!ffdp) 1520 return -EBADF; 1521 int sim_fd = ffdp->getSimFD(); 1522 1523 struct statfs hostBuf; 1524 int result = fstatfs(sim_fd, &hostBuf); 1525 1526 if (result < 0) 1527 return -errno; 1528 1529 copyOutStatfsBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf); 1530 1531 return 0; 1532} 1533 1534 1535/// Target writev() handler. 1536template <class OS> 1537SyscallReturn 1538writevFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc) 1539{ 1540 int index = 0; 1541 int tgt_fd = p->getSyscallArg(tc, index); 1542 1543 auto hbfdp = std::dynamic_pointer_cast<HBFDEntry>((*p->fds)[tgt_fd]); 1544 if (!hbfdp) 1545 return -EBADF; 1546 int sim_fd = hbfdp->getSimFD(); 1547 1548 SETranslatingPortProxy &prox = tc->getMemProxy(); 1549 uint64_t tiov_base = p->getSyscallArg(tc, index); 1550 size_t count = p->getSyscallArg(tc, index); 1551 struct iovec hiov[count]; 1552 for (size_t i = 0; i < count; ++i) { 1553 typename OS::tgt_iovec tiov; 1554 1555 prox.readBlob(tiov_base + i*sizeof(typename OS::tgt_iovec), 1556 (uint8_t*)&tiov, sizeof(typename OS::tgt_iovec)); 1557 hiov[i].iov_len = TheISA::gtoh(tiov.iov_len); 1558 hiov[i].iov_base = new char [hiov[i].iov_len]; 1559 prox.readBlob(TheISA::gtoh(tiov.iov_base), (uint8_t *)hiov[i].iov_base, 1560 hiov[i].iov_len); 1561 } 1562 1563 int result = writev(sim_fd, hiov, count); 1564 1565 for (size_t i = 0; i < count; ++i) 1566 delete [] (char *)hiov[i].iov_base; 1567 1568 if (result < 0) 1569 return -errno; 1570 1571 return result; 1572} 1573 1574/// Real mmap handler. 1575template <class OS> 1576SyscallReturn 1577mmapImpl(SyscallDesc *desc, int num, Process *p, ThreadContext *tc, 1578 bool is_mmap2) 1579{ 1580 int index = 0; 1581 Addr start = p->getSyscallArg(tc, index); 1582 uint64_t length = p->getSyscallArg(tc, index); 1583 int prot = p->getSyscallArg(tc, index); 1584 int tgt_flags = p->getSyscallArg(tc, index); 1585 int tgt_fd = p->getSyscallArg(tc, index); 1586 int offset = p->getSyscallArg(tc, index); 1587 1588 if (is_mmap2) 1589 offset *= TheISA::PageBytes; 1590 1591 if (start & (TheISA::PageBytes - 1) || 1592 offset & (TheISA::PageBytes - 1) || 1593 (tgt_flags & OS::TGT_MAP_PRIVATE && 1594 tgt_flags & OS::TGT_MAP_SHARED) || 1595 (!(tgt_flags & OS::TGT_MAP_PRIVATE) && 1596 !(tgt_flags & OS::TGT_MAP_SHARED)) || 1597 !length) { 1598 return -EINVAL; 1599 } 1600 1601 if ((prot & PROT_WRITE) && (tgt_flags & OS::TGT_MAP_SHARED)) { 1602 // With shared mmaps, there are two cases to consider: 1603 // 1) anonymous: writes should modify the mapping and this should be 1604 // visible to observers who share the mapping. Currently, it's 1605 // difficult to update the shared mapping because there's no 1606 // structure which maintains information about the which virtual 1607 // memory areas are shared. If that structure existed, it would be 1608 // possible to make the translations point to the same frames. 1609 // 2) file-backed: writes should modify the mapping and the file 1610 // which is backed by the mapping. The shared mapping problem is the 1611 // same as what was mentioned about the anonymous mappings. For 1612 // file-backed mappings, the writes to the file are difficult 1613 // because it requires syncing what the mapping holds with the file 1614 // that resides on the host system. So, any write on a real system 1615 // would cause the change to be propagated to the file mapping at 1616 // some point in the future (the inode is tracked along with the 1617 // mapping). This isn't guaranteed to always happen, but it usually 1618 // works well enough. The guarantee is provided by the msync system 1619 // call. We could force the change through with shared mappings with 1620 // a call to msync, but that again would require more information 1621 // than we currently maintain. 1622 warn("mmap: writing to shared mmap region is currently " 1623 "unsupported. The write succeeds on the target, but it " 1624 "will not be propagated to the host or shared mappings"); 1625 } 1626 1627 length = roundUp(length, TheISA::PageBytes); 1628 1629 int sim_fd = -1; 1630 uint8_t *pmap = nullptr; 1631 if (!(tgt_flags & OS::TGT_MAP_ANONYMOUS)) { 1632 std::shared_ptr<FDEntry> fdep = (*p->fds)[tgt_fd]; 1633 1634 auto dfdp = std::dynamic_pointer_cast<DeviceFDEntry>(fdep); 1635 if (dfdp) { 1636 EmulatedDriver *emul_driver = dfdp->getDriver(); 1637 return emul_driver->mmap(p, tc, start, length, prot, 1638 tgt_flags, tgt_fd, offset); 1639 } 1640 1641 auto ffdp = std::dynamic_pointer_cast<FileFDEntry>(fdep); 1642 if (!ffdp) 1643 return -EBADF; 1644 sim_fd = ffdp->getSimFD(); 1645 1646 pmap = (decltype(pmap))mmap(nullptr, length, PROT_READ, MAP_PRIVATE, 1647 sim_fd, offset); 1648 1649 if (pmap == (decltype(pmap))-1) { 1650 warn("mmap: failed to map file into host address space"); 1651 return -errno; 1652 } 1653 } 1654 1655 // Extend global mmap region if necessary. Note that we ignore the 1656 // start address unless MAP_FIXED is specified. 1657 if (!(tgt_flags & OS::TGT_MAP_FIXED)) { 1658 std::shared_ptr<MemState> mem_state = p->memState; 1659 Addr mmap_end = mem_state->getMmapEnd(); 1660 1661 start = p->mmapGrowsDown() ? mmap_end - length : mmap_end; 1662 mmap_end = p->mmapGrowsDown() ? start : mmap_end + length; 1663 1664 mem_state->setMmapEnd(mmap_end); 1665 } 1666 1667 DPRINTF_SYSCALL(Verbose, " mmap range is 0x%x - 0x%x\n", 1668 start, start + length - 1); 1669 1670 // We only allow mappings to overwrite existing mappings if 1671 // TGT_MAP_FIXED is set. Otherwise it shouldn't be a problem 1672 // because we ignore the start hint if TGT_MAP_FIXED is not set. 1673 int clobber = tgt_flags & OS::TGT_MAP_FIXED; 1674 if (clobber) { 1675 for (auto tc : p->system->threadContexts) { 1676 // If we might be overwriting old mappings, we need to 1677 // invalidate potentially stale mappings out of the TLBs. 1678 tc->getDTBPtr()->flushAll(); 1679 tc->getITBPtr()->flushAll(); 1680 } 1681 } 1682 1683 // Allocate physical memory and map it in. If the page table is already 1684 // mapped and clobber is not set, the simulator will issue throw a 1685 // fatal and bail out of the simulation. 1686 p->allocateMem(start, length, clobber); 1687 1688 // Transfer content into target address space. 1689 SETranslatingPortProxy &tp = tc->getMemProxy(); 1690 if (tgt_flags & OS::TGT_MAP_ANONYMOUS) { 1691 // In general, we should zero the mapped area for anonymous mappings, 1692 // with something like: 1693 // tp.memsetBlob(start, 0, length); 1694 // However, given that we don't support sparse mappings, and 1695 // some applications can map a couple of gigabytes of space 1696 // (intending sparse usage), that can get painfully expensive. 1697 // Fortunately, since we don't properly implement munmap either, 1698 // there's no danger of remapping used memory, so for now all 1699 // newly mapped memory should already be zeroed so we can skip it. 1700 } else { 1701 // It is possible to mmap an area larger than a file, however 1702 // accessing unmapped portions the system triggers a "Bus error" 1703 // on the host. We must know when to stop copying the file from 1704 // the host into the target address space. 1705 struct stat file_stat; 1706 if (fstat(sim_fd, &file_stat) > 0) 1707 fatal("mmap: cannot stat file"); 1708 1709 // Copy the portion of the file that is resident. This requires 1710 // checking both the mmap size and the filesize that we are 1711 // trying to mmap into this space; the mmap size also depends 1712 // on the specified offset into the file. 1713 uint64_t size = std::min((uint64_t)file_stat.st_size - offset, 1714 length); 1715 tp.writeBlob(start, pmap, size); 1716 1717 // Cleanup the mmap region before exiting this function. 1718 munmap(pmap, length); 1719 1720 // Maintain the symbol table for dynamic executables. 1721 // The loader will call mmap to map the images into its address 1722 // space and we intercept that here. We can verify that we are 1723 // executing inside the loader by checking the program counter value. 1724 // XXX: with multiprogrammed workloads or multi-node configurations, 1725 // this will not work since there is a single global symbol table. 1726 ObjectFile *interpreter = p->getInterpreter(); 1727 if (interpreter) { 1728 Addr text_start = interpreter->textBase(); 1729 Addr text_end = text_start + interpreter->textSize(); 1730 1731 Addr pc = tc->pcState().pc(); 1732 1733 if (pc >= text_start && pc < text_end) { 1734 std::shared_ptr<FDEntry> fdep = (*p->fds)[tgt_fd]; 1735 auto ffdp = std::dynamic_pointer_cast<FileFDEntry>(fdep); 1736 ObjectFile *lib = createObjectFile(ffdp->getFileName()); 1737 1738 if (lib) { 1739 lib->loadAllSymbols(debugSymbolTable, 1740 lib->textBase(), start); 1741 } 1742 } 1743 } 1744 1745 // Note that we do not zero out the remainder of the mapping. This 1746 // is done by a real system, but it probably will not affect 1747 // execution (hopefully). 1748 } 1749 1750 return start; 1751} 1752 1753template <class OS> 1754SyscallReturn 1755pwrite64Func(SyscallDesc *desc, int num, Process *p, ThreadContext *tc) 1756{ 1757 int index = 0; 1758 int tgt_fd = p->getSyscallArg(tc, index); 1759 Addr bufPtr = p->getSyscallArg(tc, index); 1760 int nbytes = p->getSyscallArg(tc, index); 1761 int offset = p->getSyscallArg(tc, index); 1762 1763 auto ffdp = std::dynamic_pointer_cast<FileFDEntry>((*p->fds)[tgt_fd]); 1764 if (!ffdp) 1765 return -EBADF; 1766 int sim_fd = ffdp->getSimFD(); 1767 1768 BufferArg bufArg(bufPtr, nbytes); 1769 bufArg.copyIn(tc->getMemProxy()); 1770 1771 int bytes_written = pwrite(sim_fd, bufArg.bufferPtr(), nbytes, offset); 1772 1773 return (bytes_written == -1) ? -errno : bytes_written; 1774} 1775 1776/// Target mmap() handler. 1777template <class OS> 1778SyscallReturn 1779mmapFunc(SyscallDesc *desc, int num, Process *p, ThreadContext *tc) 1780{ 1781 return mmapImpl<OS>(desc, num, p, tc, false); 1782} 1783 1784/// Target mmap2() handler. 1785template <class OS> 1786SyscallReturn 1787mmap2Func(SyscallDesc *desc, int num, Process *p, ThreadContext *tc) 1788{ 1789 return mmapImpl<OS>(desc, num, p, tc, true); 1790} 1791 1792/// Target getrlimit() handler. 1793template <class OS> 1794SyscallReturn 1795getrlimitFunc(SyscallDesc *desc, int callnum, Process *process, 1796 ThreadContext *tc) 1797{ 1798 int index = 0; 1799 unsigned resource = process->getSyscallArg(tc, index); 1800 TypedBufferArg<typename OS::rlimit> rlp(process->getSyscallArg(tc, index)); 1801 1802 switch (resource) { 1803 case OS::TGT_RLIMIT_STACK: 1804 // max stack size in bytes: make up a number (8MB for now) 1805 rlp->rlim_cur = rlp->rlim_max = 8 * 1024 * 1024; 1806 rlp->rlim_cur = TheISA::htog(rlp->rlim_cur); 1807 rlp->rlim_max = TheISA::htog(rlp->rlim_max); 1808 break; 1809 1810 case OS::TGT_RLIMIT_DATA: 1811 // max data segment size in bytes: make up a number 1812 rlp->rlim_cur = rlp->rlim_max = 256 * 1024 * 1024; 1813 rlp->rlim_cur = TheISA::htog(rlp->rlim_cur); 1814 rlp->rlim_max = TheISA::htog(rlp->rlim_max); 1815 break; 1816 1817 default: 1818 warn("getrlimit: unimplemented resource %d", resource); 1819 return -EINVAL; 1820 break; 1821 } 1822 1823 rlp.copyOut(tc->getMemProxy()); 1824 return 0; 1825} 1826 1827template <class OS> 1828SyscallReturn 1829prlimitFunc(SyscallDesc *desc, int callnum, Process *process, 1830 ThreadContext *tc) 1831{ 1832 int index = 0; 1833 if (process->getSyscallArg(tc, index) != 0) 1834 { 1835 warn("prlimit: ignoring rlimits for nonzero pid"); 1836 return -EPERM; 1837 } 1838 int resource = process->getSyscallArg(tc, index); 1839 Addr n = process->getSyscallArg(tc, index); 1840 if (n != 0) 1841 warn("prlimit: ignoring new rlimit"); 1842 Addr o = process->getSyscallArg(tc, index); 1843 if (o != 0) 1844 { 1845 TypedBufferArg<typename OS::rlimit> rlp(o); 1846 switch (resource) { 1847 case OS::TGT_RLIMIT_STACK: 1848 // max stack size in bytes: make up a number (8MB for now) 1849 rlp->rlim_cur = rlp->rlim_max = 8 * 1024 * 1024; 1850 rlp->rlim_cur = TheISA::htog(rlp->rlim_cur); 1851 rlp->rlim_max = TheISA::htog(rlp->rlim_max); 1852 break; 1853 case OS::TGT_RLIMIT_DATA: 1854 // max data segment size in bytes: make up a number 1855 rlp->rlim_cur = rlp->rlim_max = 256*1024*1024; 1856 rlp->rlim_cur = TheISA::htog(rlp->rlim_cur); 1857 rlp->rlim_max = TheISA::htog(rlp->rlim_max); 1858 break; 1859 default: 1860 warn("prlimit: unimplemented resource %d", resource); 1861 return -EINVAL; 1862 break; 1863 } 1864 rlp.copyOut(tc->getMemProxy()); 1865 } 1866 return 0; 1867} 1868 1869/// Target clock_gettime() function. 1870template <class OS> 1871SyscallReturn 1872clock_gettimeFunc(SyscallDesc *desc, int num, Process *p, ThreadContext *tc) 1873{ 1874 int index = 1; 1875 //int clk_id = p->getSyscallArg(tc, index); 1876 TypedBufferArg<typename OS::timespec> tp(p->getSyscallArg(tc, index)); 1877 1878 getElapsedTimeNano(tp->tv_sec, tp->tv_nsec); 1879 tp->tv_sec += seconds_since_epoch; 1880 tp->tv_sec = TheISA::htog(tp->tv_sec); 1881 tp->tv_nsec = TheISA::htog(tp->tv_nsec); 1882 1883 tp.copyOut(tc->getMemProxy()); 1884 1885 return 0; 1886} 1887 1888/// Target clock_getres() function. 1889template <class OS> 1890SyscallReturn 1891clock_getresFunc(SyscallDesc *desc, int num, Process *p, ThreadContext *tc) 1892{ 1893 int index = 1; 1894 TypedBufferArg<typename OS::timespec> tp(p->getSyscallArg(tc, index)); 1895 1896 // Set resolution at ns, which is what clock_gettime() returns 1897 tp->tv_sec = 0; 1898 tp->tv_nsec = 1; 1899 1900 tp.copyOut(tc->getMemProxy()); 1901 1902 return 0; 1903} 1904 1905/// Target gettimeofday() handler. 1906template <class OS> 1907SyscallReturn 1908gettimeofdayFunc(SyscallDesc *desc, int callnum, Process *process, 1909 ThreadContext *tc) 1910{ 1911 int index = 0; 1912 TypedBufferArg<typename OS::timeval> tp(process->getSyscallArg(tc, index)); 1913 1914 getElapsedTimeMicro(tp->tv_sec, tp->tv_usec); 1915 tp->tv_sec += seconds_since_epoch; 1916 tp->tv_sec = TheISA::htog(tp->tv_sec); 1917 tp->tv_usec = TheISA::htog(tp->tv_usec); 1918 1919 tp.copyOut(tc->getMemProxy()); 1920 1921 return 0; 1922} 1923 1924 1925/// Target utimes() handler. 1926template <class OS> 1927SyscallReturn 1928utimesFunc(SyscallDesc *desc, int callnum, Process *process, 1929 ThreadContext *tc) 1930{ 1931 std::string path; 1932 1933 int index = 0; 1934 if (!tc->getMemProxy().tryReadString(path, 1935 process->getSyscallArg(tc, index))) { 1936 return -EFAULT; 1937 } 1938 1939 TypedBufferArg<typename OS::timeval [2]> 1940 tp(process->getSyscallArg(tc, index)); 1941 tp.copyIn(tc->getMemProxy()); 1942 1943 struct timeval hostTimeval[2]; 1944 for (int i = 0; i < 2; ++i) { 1945 hostTimeval[i].tv_sec = TheISA::gtoh((*tp)[i].tv_sec); 1946 hostTimeval[i].tv_usec = TheISA::gtoh((*tp)[i].tv_usec); 1947 } 1948 1949 // Adjust path for current working directory 1950 path = process->fullPath(path); 1951 1952 int result = utimes(path.c_str(), hostTimeval); 1953 1954 if (result < 0) 1955 return -errno; 1956 1957 return 0; 1958} 1959 1960template <class OS> 1961SyscallReturn 1962execveFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc) 1963{ 1964 desc->setFlags(0); 1965 1966 int index = 0; 1967 std::string path; 1968 SETranslatingPortProxy & mem_proxy = tc->getMemProxy(); 1969 if (!mem_proxy.tryReadString(path, p->getSyscallArg(tc, index))) 1970 return -EFAULT; 1971 1972 if (access(path.c_str(), F_OK) == -1) 1973 return -EACCES; 1974 1975 auto read_in = [](std::vector<std::string> & vect, 1976 SETranslatingPortProxy & mem_proxy, 1977 Addr mem_loc) 1978 { 1979 for (int inc = 0; ; inc++) { 1980 BufferArg b((mem_loc + sizeof(Addr) * inc), sizeof(Addr)); 1981 b.copyIn(mem_proxy); 1982 1983 if (!*(Addr*)b.bufferPtr()) 1984 break; 1985 1986 vect.push_back(std::string()); 1987 mem_proxy.tryReadString(vect[inc], *(Addr*)b.bufferPtr()); 1988 } 1989 }; 1990 1991 /** 1992 * Note that ProcessParams is generated by swig and there are no other 1993 * examples of how to create anything but this default constructor. The 1994 * fields are manually initialized instead of passing parameters to the 1995 * constructor. 1996 */ 1997 ProcessParams *pp = new ProcessParams(); 1998 pp->executable = path; 1999 Addr argv_mem_loc = p->getSyscallArg(tc, index); 2000 read_in(pp->cmd, mem_proxy, argv_mem_loc); 2001 Addr envp_mem_loc = p->getSyscallArg(tc, index); 2002 read_in(pp->env, mem_proxy, envp_mem_loc); 2003 pp->uid = p->uid(); 2004 pp->egid = p->egid(); 2005 pp->euid = p->euid(); 2006 pp->gid = p->gid(); 2007 pp->ppid = p->ppid(); 2008 pp->pid = p->pid(); 2009 pp->input.assign("cin"); 2010 pp->output.assign("cout"); 2011 pp->errout.assign("cerr"); 2012 pp->cwd.assign(p->getcwd()); 2013 pp->system = p->system; 2014 /** 2015 * Prevent process object creation with identical PIDs (which will trip 2016 * a fatal check in Process constructor). The execve call is supposed to 2017 * take over the currently executing process' identity but replace 2018 * whatever it is doing with a new process image. Instead of hijacking 2019 * the process object in the simulator, we create a new process object 2020 * and bind to the previous process' thread below (hijacking the thread). 2021 */ 2022 p->system->PIDs.erase(p->pid()); 2023 Process *new_p = pp->create(); 2024 delete pp; 2025 2026 /** 2027 * Work through the file descriptor array and close any files marked 2028 * close-on-exec. 2029 */ 2030 new_p->fds = p->fds; 2031 for (int i = 0; i < new_p->fds->getSize(); i++) { 2032 std::shared_ptr<FDEntry> fdep = (*new_p->fds)[i]; 2033 if (fdep && fdep->getCOE()) 2034 new_p->fds->closeFDEntry(i); 2035 } 2036 2037 *new_p->sigchld = true; 2038 2039 delete p; 2040 tc->clearArchRegs(); 2041 tc->setProcessPtr(new_p); 2042 new_p->assignThreadContext(tc->contextId()); 2043 new_p->initState(); 2044 tc->activate(); 2045 TheISA::PCState pcState = tc->pcState(); 2046 tc->setNPC(pcState.instAddr()); 2047 2048 desc->setFlags(SyscallDesc::SuppressReturnValue); 2049 return 0; 2050} 2051 2052/// Target getrusage() function. 2053template <class OS> 2054SyscallReturn 2055getrusageFunc(SyscallDesc *desc, int callnum, Process *process, 2056 ThreadContext *tc) 2057{ 2058 int index = 0; 2059 int who = process->getSyscallArg(tc, index); // THREAD, SELF, or CHILDREN 2060 TypedBufferArg<typename OS::rusage> rup(process->getSyscallArg(tc, index)); 2061 2062 rup->ru_utime.tv_sec = 0; 2063 rup->ru_utime.tv_usec = 0; 2064 rup->ru_stime.tv_sec = 0; 2065 rup->ru_stime.tv_usec = 0; 2066 rup->ru_maxrss = 0; 2067 rup->ru_ixrss = 0; 2068 rup->ru_idrss = 0; 2069 rup->ru_isrss = 0; 2070 rup->ru_minflt = 0; 2071 rup->ru_majflt = 0; 2072 rup->ru_nswap = 0; 2073 rup->ru_inblock = 0; 2074 rup->ru_oublock = 0; 2075 rup->ru_msgsnd = 0; 2076 rup->ru_msgrcv = 0; 2077 rup->ru_nsignals = 0; 2078 rup->ru_nvcsw = 0; 2079 rup->ru_nivcsw = 0; 2080 2081 switch (who) { 2082 case OS::TGT_RUSAGE_SELF: 2083 getElapsedTimeMicro(rup->ru_utime.tv_sec, rup->ru_utime.tv_usec); 2084 rup->ru_utime.tv_sec = TheISA::htog(rup->ru_utime.tv_sec); 2085 rup->ru_utime.tv_usec = TheISA::htog(rup->ru_utime.tv_usec); 2086 break; 2087 2088 case OS::TGT_RUSAGE_CHILDREN: 2089 // do nothing. We have no child processes, so they take no time. 2090 break; 2091 2092 default: 2093 // don't really handle THREAD or CHILDREN, but just warn and 2094 // plow ahead 2095 warn("getrusage() only supports RUSAGE_SELF. Parameter %d ignored.", 2096 who); 2097 } 2098 2099 rup.copyOut(tc->getMemProxy()); 2100 2101 return 0; 2102} 2103 2104/// Target times() function. 2105template <class OS> 2106SyscallReturn 2107timesFunc(SyscallDesc *desc, int callnum, Process *process, 2108 ThreadContext *tc) 2109{ 2110 int index = 0; 2111 TypedBufferArg<typename OS::tms> bufp(process->getSyscallArg(tc, index)); 2112 2113 // Fill in the time structure (in clocks) 2114 int64_t clocks = curTick() * OS::M5_SC_CLK_TCK / SimClock::Int::s; 2115 bufp->tms_utime = clocks; 2116 bufp->tms_stime = 0; 2117 bufp->tms_cutime = 0; 2118 bufp->tms_cstime = 0; 2119 2120 // Convert to host endianness 2121 bufp->tms_utime = TheISA::htog(bufp->tms_utime); 2122 2123 // Write back 2124 bufp.copyOut(tc->getMemProxy()); 2125 2126 // Return clock ticks since system boot 2127 return clocks; 2128} 2129 2130/// Target time() function. 2131template <class OS> 2132SyscallReturn 2133timeFunc(SyscallDesc *desc, int callnum, Process *process, ThreadContext *tc) 2134{ 2135 typename OS::time_t sec, usec; 2136 getElapsedTimeMicro(sec, usec); 2137 sec += seconds_since_epoch; 2138 2139 int index = 0; 2140 Addr taddr = (Addr)process->getSyscallArg(tc, index); 2141 if (taddr != 0) { 2142 typename OS::time_t t = sec; 2143 t = TheISA::htog(t); 2144 SETranslatingPortProxy &p = tc->getMemProxy(); 2145 p.writeBlob(taddr, (uint8_t*)&t, (int)sizeof(typename OS::time_t)); 2146 } 2147 return sec; 2148} 2149 2150template <class OS> 2151SyscallReturn 2152tgkillFunc(SyscallDesc *desc, int num, Process *process, ThreadContext *tc) 2153{ 2154 int index = 0; 2155 int tgid = process->getSyscallArg(tc, index); 2156 int tid = process->getSyscallArg(tc, index); 2157 int sig = process->getSyscallArg(tc, index); 2158 2159 /** 2160 * This system call is intended to allow killing a specific thread 2161 * within an arbitrary thread group if sanctioned with permission checks. 2162 * It's usually true that threads share the termination signal as pointed 2163 * out by the pthread_kill man page and this seems to be the intended 2164 * usage. Due to this being an emulated environment, assume the following: 2165 * Threads are allowed to call tgkill because the EUID for all threads 2166 * should be the same. There is no signal handling mechanism for kernel 2167 * registration of signal handlers since signals are poorly supported in 2168 * emulation mode. Since signal handlers cannot be registered, all 2169 * threads within in a thread group must share the termination signal. 2170 * We never exhaust PIDs so there's no chance of finding the wrong one 2171 * due to PID rollover. 2172 */ 2173 2174 System *sys = tc->getSystemPtr(); 2175 Process *tgt_proc = nullptr; 2176 for (int i = 0; i < sys->numContexts(); i++) { 2177 Process *temp = sys->threadContexts[i]->getProcessPtr(); 2178 if (temp->pid() == tid) { 2179 tgt_proc = temp; 2180 break; 2181 } 2182 } 2183 2184 if (sig != 0 || sig != OS::TGT_SIGABRT) 2185 return -EINVAL; 2186 2187 if (tgt_proc == nullptr) 2188 return -ESRCH; 2189 2190 if (tgid != -1 && tgt_proc->tgid() != tgid) 2191 return -ESRCH; 2192 2193 if (sig == OS::TGT_SIGABRT) 2194 exitGroupFunc(desc, 252, process, tc); 2195 2196 return 0; 2197} 2198 2199template <class OS> 2200SyscallReturn 2201socketFunc(SyscallDesc *desc, int num, Process *p, ThreadContext *tc) 2202{ 2203 int index = 0; 2204 int domain = p->getSyscallArg(tc, index); 2205 int type = p->getSyscallArg(tc, index); 2206 int prot = p->getSyscallArg(tc, index); 2207 2208 int sim_fd = socket(domain, type, prot); 2209 if (sim_fd == -1) 2210 return -errno; 2211 2212 auto sfdp = std::make_shared<SocketFDEntry>(sim_fd, domain, type, prot); 2213 int tgt_fd = p->fds->allocFD(sfdp); 2214 2215 return tgt_fd; 2216} 2217 2218template <class OS> 2219SyscallReturn 2220socketpairFunc(SyscallDesc *desc, int num, Process *p, ThreadContext *tc) 2221{ 2222 int index = 0; 2223 int domain = p->getSyscallArg(tc, index); 2224 int type = p->getSyscallArg(tc, index); 2225 int prot = p->getSyscallArg(tc, index); 2226 Addr svPtr = p->getSyscallArg(tc, index); 2227 2228 BufferArg svBuf((Addr)svPtr, 2 * sizeof(int)); 2229 int status = socketpair(domain, type, prot, (int *)svBuf.bufferPtr()); 2230 if (status == -1) 2231 return -errno; 2232 2233 int *fds = (int *)svBuf.bufferPtr(); 2234 2235 auto sfdp1 = std::make_shared<SocketFDEntry>(fds[0], domain, type, prot); 2236 fds[0] = p->fds->allocFD(sfdp1); 2237 auto sfdp2 = std::make_shared<SocketFDEntry>(fds[1], domain, type, prot); 2238 fds[1] = p->fds->allocFD(sfdp2); 2239 svBuf.copyOut(tc->getMemProxy()); 2240 2241 return status; 2242} 2243 2244template <class OS> 2245SyscallReturn 2246selectFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc) 2247{ 2248 int retval; 2249 2250 int index = 0; 2251 int nfds_t = p->getSyscallArg(tc, index); 2252 Addr fds_read_ptr = p->getSyscallArg(tc, index); 2253 Addr fds_writ_ptr = p->getSyscallArg(tc, index); 2254 Addr fds_excp_ptr = p->getSyscallArg(tc, index); 2255 Addr time_val_ptr = p->getSyscallArg(tc, index); 2256 2257 TypedBufferArg<typename OS::fd_set> rd_t(fds_read_ptr); 2258 TypedBufferArg<typename OS::fd_set> wr_t(fds_writ_ptr); 2259 TypedBufferArg<typename OS::fd_set> ex_t(fds_excp_ptr); 2260 TypedBufferArg<typename OS::timeval> tp(time_val_ptr); 2261 2262 /** 2263 * Host fields. Notice that these use the definitions from the system 2264 * headers instead of the gem5 headers and libraries. If the host and 2265 * target have different header file definitions, this will not work. 2266 */ 2267 fd_set rd_h; 2268 FD_ZERO(&rd_h); 2269 fd_set wr_h; 2270 FD_ZERO(&wr_h); 2271 fd_set ex_h; 2272 FD_ZERO(&ex_h); 2273 2274 /** 2275 * Copy in the fd_set from the target. 2276 */ 2277 if (fds_read_ptr) 2278 rd_t.copyIn(tc->getMemProxy()); 2279 if (fds_writ_ptr) 2280 wr_t.copyIn(tc->getMemProxy()); 2281 if (fds_excp_ptr) 2282 ex_t.copyIn(tc->getMemProxy()); 2283 2284 /** 2285 * We need to translate the target file descriptor set into a host file 2286 * descriptor set. This involves both our internal process fd array 2287 * and the fd_set defined in Linux header files. The nfds field also 2288 * needs to be updated as it will be only target specific after 2289 * retrieving it from the target; the nfds value is expected to be the 2290 * highest file descriptor that needs to be checked, so we need to extend 2291 * it out for nfds_h when we do the update. 2292 */ 2293 int nfds_h = 0; 2294 std::map<int, int> trans_map; 2295 auto try_add_host_set = [&](fd_set *tgt_set_entry, 2296 fd_set *hst_set_entry, 2297 int iter) -> bool 2298 { 2299 /** 2300 * By this point, we know that we are looking at a valid file 2301 * descriptor set on the target. We need to check if the target file 2302 * descriptor value passed in as iter is part of the set. 2303 */ 2304 if (FD_ISSET(iter, tgt_set_entry)) { 2305 /** 2306 * We know that the target file descriptor belongs to the set, 2307 * but we do not yet know if the file descriptor is valid or 2308 * that we have a host mapping. Check that now. 2309 */ 2310 auto hbfdp = std::dynamic_pointer_cast<HBFDEntry>((*p->fds)[iter]); 2311 if (!hbfdp) 2312 return true; 2313 auto sim_fd = hbfdp->getSimFD(); 2314 2315 /** 2316 * Add the sim_fd to tgt_fd translation into trans_map for use 2317 * later when we need to zero the target fd_set structures and 2318 * then update them with hits returned from the host select call. 2319 */ 2320 trans_map[sim_fd] = iter; 2321 2322 /** 2323 * We know that the host file descriptor exists so now we check 2324 * if we need to update the max count for nfds_h before passing 2325 * the duplicated structure into the host. 2326 */ 2327 nfds_h = std::max(nfds_h - 1, sim_fd + 1); 2328 2329 /** 2330 * Add the host file descriptor to the set that we are going to 2331 * pass into the host. 2332 */ 2333 FD_SET(sim_fd, hst_set_entry); 2334 } 2335 return false; 2336 }; 2337 2338 for (int i = 0; i < nfds_t; i++) { 2339 if (fds_read_ptr) { 2340 bool ebadf = try_add_host_set((fd_set*)&*rd_t, &rd_h, i); 2341 if (ebadf) return -EBADF; 2342 } 2343 if (fds_writ_ptr) { 2344 bool ebadf = try_add_host_set((fd_set*)&*wr_t, &wr_h, i); 2345 if (ebadf) return -EBADF; 2346 } 2347 if (fds_excp_ptr) { 2348 bool ebadf = try_add_host_set((fd_set*)&*ex_t, &ex_h, i); 2349 if (ebadf) return -EBADF; 2350 } 2351 } 2352 2353 if (time_val_ptr) { 2354 /** 2355 * It might be possible to decrement the timeval based on some 2356 * derivation of wall clock determined from elapsed simulator ticks 2357 * but that seems like overkill. Rather, we just set the timeval with 2358 * zero timeout. (There is no reason to block during the simulation 2359 * as it only decreases simulator performance.) 2360 */ 2361 tp->tv_sec = 0; 2362 tp->tv_usec = 0; 2363 2364 retval = select(nfds_h, 2365 fds_read_ptr ? &rd_h : nullptr, 2366 fds_writ_ptr ? &wr_h : nullptr, 2367 fds_excp_ptr ? &ex_h : nullptr, 2368 (timeval*)&*tp); 2369 } else { 2370 /** 2371 * If the timeval pointer is null, setup a new timeval structure to 2372 * pass into the host select call. Unfortunately, we will need to 2373 * manually check the return value and throw a retry fault if the 2374 * return value is zero. Allowing the system call to block will 2375 * likely deadlock the event queue. 2376 */ 2377 struct timeval tv = { 0, 0 }; 2378 2379 retval = select(nfds_h, 2380 fds_read_ptr ? &rd_h : nullptr, 2381 fds_writ_ptr ? &wr_h : nullptr, 2382 fds_excp_ptr ? &ex_h : nullptr, 2383 &tv); 2384 2385 if (retval == 0) { 2386 /** 2387 * If blocking indefinitely, check the signal list to see if a 2388 * signal would break the poll out of the retry cycle and try to 2389 * return the signal interrupt instead. 2390 */ 2391 for (auto sig : tc->getSystemPtr()->signalList) 2392 if (sig.receiver == p) 2393 return -EINTR; 2394 return SyscallReturn::retry(); 2395 } 2396 } 2397 2398 if (retval == -1) 2399 return -errno; 2400 2401 FD_ZERO((fd_set*)&*rd_t); 2402 FD_ZERO((fd_set*)&*wr_t); 2403 FD_ZERO((fd_set*)&*ex_t); 2404 2405 /** 2406 * We need to translate the host file descriptor set into a target file 2407 * descriptor set. This involves both our internal process fd array 2408 * and the fd_set defined in header files. 2409 */ 2410 for (int i = 0; i < nfds_h; i++) { 2411 if (fds_read_ptr) { 2412 if (FD_ISSET(i, &rd_h)) 2413 FD_SET(trans_map[i], (fd_set*)&*rd_t); 2414 } 2415 2416 if (fds_writ_ptr) { 2417 if (FD_ISSET(i, &wr_h)) 2418 FD_SET(trans_map[i], (fd_set*)&*wr_t); 2419 } 2420 2421 if (fds_excp_ptr) { 2422 if (FD_ISSET(i, &ex_h)) 2423 FD_SET(trans_map[i], (fd_set*)&*ex_t); 2424 } 2425 } 2426 2427 if (fds_read_ptr) 2428 rd_t.copyOut(tc->getMemProxy()); 2429 if (fds_writ_ptr) 2430 wr_t.copyOut(tc->getMemProxy()); 2431 if (fds_excp_ptr) 2432 ex_t.copyOut(tc->getMemProxy()); 2433 if (time_val_ptr) 2434 tp.copyOut(tc->getMemProxy()); 2435 2436 return retval; 2437} 2438 2439template <class OS> 2440SyscallReturn 2441readFunc(SyscallDesc *desc, int num, Process *p, ThreadContext *tc) 2442{ 2443 int index = 0; 2444 int tgt_fd = p->getSyscallArg(tc, index); 2445 Addr buf_ptr = p->getSyscallArg(tc, index); 2446 int nbytes = p->getSyscallArg(tc, index); 2447 2448 auto hbfdp = std::dynamic_pointer_cast<HBFDEntry>((*p->fds)[tgt_fd]); 2449 if (!hbfdp) 2450 return -EBADF; 2451 int sim_fd = hbfdp->getSimFD(); 2452 2453 struct pollfd pfd; 2454 pfd.fd = sim_fd; 2455 pfd.events = POLLIN | POLLPRI; 2456 if ((poll(&pfd, 1, 0) == 0) 2457 && !(hbfdp->getFlags() & OS::TGT_O_NONBLOCK)) 2458 return SyscallReturn::retry(); 2459 2460 BufferArg buf_arg(buf_ptr, nbytes); 2461 int bytes_read = read(sim_fd, buf_arg.bufferPtr(), nbytes); 2462 2463 if (bytes_read > 0) 2464 buf_arg.copyOut(tc->getMemProxy()); 2465 2466 return (bytes_read == -1) ? -errno : bytes_read; 2467} 2468 2469template <class OS> 2470SyscallReturn 2471writeFunc(SyscallDesc *desc, int num, Process *p, ThreadContext *tc) 2472{ 2473 int index = 0; 2474 int tgt_fd = p->getSyscallArg(tc, index); 2475 Addr buf_ptr = p->getSyscallArg(tc, index); 2476 int nbytes = p->getSyscallArg(tc, index); 2477 2478 auto hbfdp = std::dynamic_pointer_cast<HBFDEntry>((*p->fds)[tgt_fd]); 2479 if (!hbfdp) 2480 return -EBADF; 2481 int sim_fd = hbfdp->getSimFD(); 2482 2483 BufferArg buf_arg(buf_ptr, nbytes); 2484 buf_arg.copyIn(tc->getMemProxy()); 2485 2486 struct pollfd pfd; 2487 pfd.fd = sim_fd; 2488 pfd.events = POLLOUT; 2489 2490 /** 2491 * We don't want to poll on /dev/random. The kernel will not enable the 2492 * file descriptor for writing unless the entropy in the system falls 2493 * below write_wakeup_threshold. This is not guaranteed to happen 2494 * depending on host settings. 2495 */ 2496 auto ffdp = std::dynamic_pointer_cast<FileFDEntry>(hbfdp); 2497 if (ffdp && (ffdp->getFileName() != "/dev/random")) { 2498 if (!poll(&pfd, 1, 0) && !(ffdp->getFlags() & OS::TGT_O_NONBLOCK)) 2499 return SyscallReturn::retry(); 2500 } 2501 2502 int bytes_written = write(sim_fd, buf_arg.bufferPtr(), nbytes); 2503 2504 if (bytes_written != -1) 2505 fsync(sim_fd); 2506 2507 return (bytes_written == -1) ? -errno : bytes_written; 2508} 2509 2510template <class OS> 2511SyscallReturn 2512wait4Func(SyscallDesc *desc, int num, Process *p, ThreadContext *tc) 2513{ 2514 int index = 0; 2515 pid_t pid = p->getSyscallArg(tc, index); 2516 Addr statPtr = p->getSyscallArg(tc, index); 2517 int options = p->getSyscallArg(tc, index); 2518 Addr rusagePtr = p->getSyscallArg(tc, index); 2519 2520 if (rusagePtr) 2521 DPRINTFR(SyscallVerbose, 2522 "%d: %s: syscall wait4: rusage pointer provided however " 2523 "functionality not supported. Ignoring rusage pointer.\n", 2524 curTick(), tc->getCpuPtr()->name()); 2525 2526 /** 2527 * Currently, wait4 is only implemented so that it will wait for children 2528 * exit conditions which are denoted by a SIGCHLD signals posted into the 2529 * system signal list. We return no additional information via any of the 2530 * parameters supplied to wait4. If nothing is found in the system signal 2531 * list, we will wait indefinitely for SIGCHLD to post by retrying the 2532 * call. 2533 */ 2534 System *sysh = tc->getSystemPtr(); 2535 std::list<BasicSignal>::iterator iter; 2536 for (iter=sysh->signalList.begin(); iter!=sysh->signalList.end(); iter++) { 2537 if (iter->receiver == p) { 2538 if (pid < -1) { 2539 if ((iter->sender->pgid() == -pid) 2540 && (iter->signalValue == OS::TGT_SIGCHLD)) 2541 goto success; 2542 } else if (pid == -1) { 2543 if (iter->signalValue == OS::TGT_SIGCHLD) 2544 goto success; 2545 } else if (pid == 0) { 2546 if ((iter->sender->pgid() == p->pgid()) 2547 && (iter->signalValue == OS::TGT_SIGCHLD)) 2548 goto success; 2549 } else { 2550 if ((iter->sender->pid() == pid) 2551 && (iter->signalValue == OS::TGT_SIGCHLD)) 2552 goto success; 2553 } 2554 } 2555 } 2556 2557 return (options & OS::TGT_WNOHANG) ? 0 : SyscallReturn::retry(); 2558 2559success: 2560 // Set status to EXITED for WIFEXITED evaluations. 2561 const int EXITED = 0; 2562 BufferArg statusBuf(statPtr, sizeof(int)); 2563 *(int *)statusBuf.bufferPtr() = EXITED; 2564 statusBuf.copyOut(tc->getMemProxy()); 2565 2566 // Return the child PID. 2567 pid_t retval = iter->sender->pid(); 2568 sysh->signalList.erase(iter); 2569 return retval; 2570} 2571 2572template <class OS> 2573SyscallReturn 2574acceptFunc(SyscallDesc *desc, int num, Process *p, ThreadContext *tc) 2575{ 2576 struct sockaddr sa; 2577 socklen_t addrLen; 2578 int host_fd; 2579 int index = 0; 2580 int tgt_fd = p->getSyscallArg(tc, index); 2581 Addr addrPtr = p->getSyscallArg(tc, index); 2582 Addr lenPtr = p->getSyscallArg(tc, index); 2583 2584 BufferArg *lenBufPtr = nullptr; 2585 BufferArg *addrBufPtr = nullptr; 2586 2587 auto sfdp = std::dynamic_pointer_cast<SocketFDEntry>((*p->fds)[tgt_fd]); 2588 if (!sfdp) 2589 return -EBADF; 2590 int sim_fd = sfdp->getSimFD(); 2591 2592 /** 2593 * We poll the socket file descriptor first to guarantee that we do not 2594 * block on our accept call. The socket can be opened without the 2595 * non-blocking flag (it blocks). This will cause deadlocks between 2596 * communicating processes. 2597 */ 2598 struct pollfd pfd; 2599 pfd.fd = sim_fd; 2600 pfd.events = POLLIN | POLLPRI; 2601 if ((poll(&pfd, 1, 0) == 0) 2602 && !(sfdp->getFlags() & OS::TGT_O_NONBLOCK)) 2603 return SyscallReturn::retry(); 2604 2605 if (lenPtr) { 2606 lenBufPtr = new BufferArg(lenPtr, sizeof(socklen_t)); 2607 lenBufPtr->copyIn(tc->getMemProxy()); 2608 memcpy(&addrLen, (socklen_t *)lenBufPtr->bufferPtr(), 2609 sizeof(socklen_t)); 2610 } 2611 2612 if (addrPtr) { 2613 addrBufPtr = new BufferArg(addrPtr, sizeof(struct sockaddr)); 2614 addrBufPtr->copyIn(tc->getMemProxy()); 2615 memcpy(&sa, (struct sockaddr *)addrBufPtr->bufferPtr(), 2616 sizeof(struct sockaddr)); 2617 } 2618 2619 host_fd = accept(sim_fd, &sa, &addrLen); 2620 2621 if (host_fd == -1) 2622 return -errno; 2623 2624 if (addrPtr) { 2625 memcpy(addrBufPtr->bufferPtr(), &sa, sizeof(sa)); 2626 addrBufPtr->copyOut(tc->getMemProxy()); 2627 delete(addrBufPtr); 2628 } 2629 2630 if (lenPtr) { 2631 *(socklen_t *)lenBufPtr->bufferPtr() = addrLen; 2632 lenBufPtr->copyOut(tc->getMemProxy()); 2633 delete(lenBufPtr); 2634 } 2635 2636 auto afdp = std::make_shared<SocketFDEntry>(host_fd, sfdp->_domain, 2637 sfdp->_type, sfdp->_protocol); 2638 return p->fds->allocFD(afdp); 2639} 2640 2641#endif // __SIM_SYSCALL_EMUL_HH__ 2642