src/sim/syscall_emul.hh

   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 <sys/mman.h>
  82 #include <sys/stat.h>
  83 #if (NO_STATFS == 0)
  84 #include <sys/statfs.h>
  85 #else
  86 #include <sys/mount.h>
  87 #endif
  88 #include <sys/time.h>
  89 #include <sys/uio.h>
  90 #include <unistd.h>
  91
  92 #include <cerrno>
  93 #include <memory>
  94 #include <string>
  95
  96 #include "arch/utility.hh"
  97 #include "base/intmath.hh"
  98 #include "base/loader/object_file.hh"
  99 #include "base/misc.hh"
 100 #include "base/trace.hh"
 101 #include "base/types.hh"
 102 #include "config/the_isa.hh"
 103 #include "cpu/base.hh"
 104 #include "cpu/thread_context.hh"
 105 #include "mem/page_table.hh"
 106 #include "params/Process.hh"
 107 #include "sim/emul_driver.hh"
 108 #include "sim/futex_map.hh"
 109 #include "sim/process.hh"
 110 #include "sim/syscall_debug_macros.hh"
 111 #include "sim/syscall_desc.hh"
 112 #include "sim/syscall_emul_buf.hh"
 113 #include "sim/syscall_return.hh"
 114
 115 //////////////////////////////////////////////////////////////////////
 116 //
 117 // The following emulation functions are generic enough that they
 118 // don't need to be recompiled for different emulated OS's.  They are
 119 // defined in sim/syscall_emul.cc.
 120 //
 121 //////////////////////////////////////////////////////////////////////
 122
 123
 124 /// Handler for unimplemented syscalls that we haven't thought about.
 125 SyscallReturn unimplementedFunc(SyscallDesc *desc, int num,
 126                                 Process *p, ThreadContext *tc);
 127
 128 /// Handler for unimplemented syscalls that we never intend to
 129 /// implement (signal handling, etc.) and should not affect the correct
 130 /// behavior of the program.  Print a warning only if the appropriate
 131 /// trace flag is enabled.  Return success to the target program.
 132 SyscallReturn ignoreFunc(SyscallDesc *desc, int num,
 133                          Process *p, ThreadContext *tc);
 134
 135 // Target fallocateFunc() handler.
 136 SyscallReturn fallocateFunc(SyscallDesc *desc, int num,
 137                             Process *p, ThreadContext *tc);
 138
 139 /// Target exit() handler: terminate current context.
 140 SyscallReturn exitFunc(SyscallDesc *desc, int num,
 141                        Process *p, ThreadContext *tc);
 142
 143 /// Target exit_group() handler: terminate simulation. (exit all threads)
 144 SyscallReturn exitGroupFunc(SyscallDesc *desc, int num,
 145                        Process *p, ThreadContext *tc);
 146
 147 /// Target set_tid_address() handler.
 148 SyscallReturn setTidAddressFunc(SyscallDesc *desc, int num,
 149                                 Process *p, ThreadContext *tc);
 150
 151 /// Target getpagesize() handler.
 152 SyscallReturn getpagesizeFunc(SyscallDesc *desc, int num,
 153                               Process *p, ThreadContext *tc);
 154
 155 /// Target brk() handler: set brk address.
 156 SyscallReturn brkFunc(SyscallDesc *desc, int num,
 157                       Process *p, ThreadContext *tc);
 158
 159 /// Target close() handler.
 160 SyscallReturn closeFunc(SyscallDesc *desc, int num,
 161                         Process *p, ThreadContext *tc);
 162
 163 // Target read() handler.
 164 SyscallReturn readFunc(SyscallDesc *desc, int num,
 165                        Process *p, ThreadContext *tc);
 166
 167 /// Target write() handler.
 168 SyscallReturn writeFunc(SyscallDesc *desc, int num,
 169                         Process *p, ThreadContext *tc);
 170
 171 /// Target lseek() handler.
 172 SyscallReturn lseekFunc(SyscallDesc *desc, int num,
 173                         Process *p, ThreadContext *tc);
 174
 175 /// Target _llseek() handler.
 176 SyscallReturn _llseekFunc(SyscallDesc *desc, int num,
 177                           Process *p, ThreadContext *tc);
 178
 179 /// Target munmap() handler.
 180 SyscallReturn munmapFunc(SyscallDesc *desc, int num,
 181                          Process *p, ThreadContext *tc);
 182
 183 /// Target gethostname() handler.
 184 SyscallReturn gethostnameFunc(SyscallDesc *desc, int num,
 185                               Process *p, ThreadContext *tc);
 186
 187 /// Target getcwd() handler.
 188 SyscallReturn getcwdFunc(SyscallDesc *desc, int num,
 189                          Process *p, ThreadContext *tc);
 190
 191 /// Target readlink() handler.
 192 SyscallReturn readlinkFunc(SyscallDesc *desc, int num,
 193                            Process *p, ThreadContext *tc,
 194                            int index = 0);
 195 SyscallReturn readlinkFunc(SyscallDesc *desc, int num,
 196                            Process *p, ThreadContext *tc);
 197
 198 /// Target unlink() handler.
 199 SyscallReturn unlinkHelper(SyscallDesc *desc, int num,
 200                            Process *p, ThreadContext *tc,
 201                            int index);
 202 SyscallReturn unlinkFunc(SyscallDesc *desc, int num,
 203                          Process *p, ThreadContext *tc);
 204
 205 /// Target mkdir() handler.
 206 SyscallReturn mkdirFunc(SyscallDesc *desc, int num,
 207                         Process *p, ThreadContext *tc);
 208
 209 /// Target rename() handler.
 210 SyscallReturn renameFunc(SyscallDesc *desc, int num,
 211                          Process *p, ThreadContext *tc);
 212
 213
 214 /// Target truncate() handler.
 215 SyscallReturn truncateFunc(SyscallDesc *desc, int num,
 216                            Process *p, ThreadContext *tc);
 217
 218
 219 /// Target ftruncate() handler.
 220 SyscallReturn ftruncateFunc(SyscallDesc *desc, int num,
 221                             Process *p, ThreadContext *tc);
 222
 223
 224 /// Target truncate64() handler.
 225 SyscallReturn truncate64Func(SyscallDesc *desc, int num,
 226                              Process *p, ThreadContext *tc);
 227
 228 /// Target ftruncate64() handler.
 229 SyscallReturn ftruncate64Func(SyscallDesc *desc, int num,
 230                               Process *p, ThreadContext *tc);
 231
 232
 233 /// Target umask() handler.
 234 SyscallReturn umaskFunc(SyscallDesc *desc, int num,
 235                         Process *p, ThreadContext *tc);
 236
 237 /// Target gettid() handler.
 238 SyscallReturn gettidFunc(SyscallDesc *desc, int num,
 239                          Process *p, ThreadContext *tc);
 240
 241 /// Target chown() handler.
 242 SyscallReturn chownFunc(SyscallDesc *desc, int num,
 243                         Process *p, ThreadContext *tc);
 244
 245 /// Target setpgid() handler.
 246 SyscallReturn setpgidFunc(SyscallDesc *desc, int num,
 247                           Process *p, ThreadContext *tc);
 248
 249 /// Target fchown() handler.
 250 SyscallReturn fchownFunc(SyscallDesc *desc, int num,
 251                          Process *p, ThreadContext *tc);
 252
 253 /// Target dup() handler.
 254 SyscallReturn dupFunc(SyscallDesc *desc, int num,
 255                       Process *process, ThreadContext *tc);
 256
 257 /// Target dup2() handler.
 258 SyscallReturn dup2Func(SyscallDesc *desc, int num,
 259                        Process *process, ThreadContext *tc);
 260
 261 /// Target fcntl() handler.
 262 SyscallReturn fcntlFunc(SyscallDesc *desc, int num,
 263                         Process *process, ThreadContext *tc);
 264
 265 /// Target fcntl64() handler.
 266 SyscallReturn fcntl64Func(SyscallDesc *desc, int num,
 267                           Process *process, ThreadContext *tc);
 268
 269 /// Target setuid() handler.
 270 SyscallReturn setuidFunc(SyscallDesc *desc, int num,
 271                          Process *p, ThreadContext *tc);
 272
 273 /// Target pipe() handler.
 274 SyscallReturn pipeFunc(SyscallDesc *desc, int num,
 275                        Process *p, ThreadContext *tc);
 276
 277 /// Internal pipe() handler.
 278 SyscallReturn pipeImpl(SyscallDesc *desc, int num, Process *p,
 279                        ThreadContext *tc, bool pseudoPipe);
 280
 281 /// Target getpid() handler.
 282 SyscallReturn getpidFunc(SyscallDesc *desc, int num,
 283                          Process *p, ThreadContext *tc);
 284
 285 /// Target getuid() handler.
 286 SyscallReturn getuidFunc(SyscallDesc *desc, int num,
 287                          Process *p, ThreadContext *tc);
 288
 289 /// Target getgid() handler.
 290 SyscallReturn getgidFunc(SyscallDesc *desc, int num,
 291                          Process *p, ThreadContext *tc);
 292
 293 /// Target getppid() handler.
 294 SyscallReturn getppidFunc(SyscallDesc *desc, int num,
 295                           Process *p, ThreadContext *tc);
 296
 297 /// Target geteuid() handler.
 298 SyscallReturn geteuidFunc(SyscallDesc *desc, int num,
 299                           Process *p, ThreadContext *tc);
 300
 301 /// Target getegid() handler.
 302 SyscallReturn getegidFunc(SyscallDesc *desc, int num,
 303                           Process *p, ThreadContext *tc);
 304
 305 /// Target access() handler
 306 SyscallReturn accessFunc(SyscallDesc *desc, int num,
 307                          Process *p, ThreadContext *tc);
 308 SyscallReturn accessFunc(SyscallDesc *desc, int num,
 309                          Process *p, ThreadContext *tc,
 310                          int index);
 311
 312 /// Futex system call
 313 /// Implemented by Daniel Sanchez
 314 /// Used by printf's in multi-threaded apps
 315 template <class OS>
 316 SyscallReturn
 317 futexFunc(SyscallDesc *desc, int callnum, Process *process,
 318           ThreadContext *tc)
 319 {
 320     using namespace std;
 321
 322     int index = 0;
 323     Addr uaddr = process->getSyscallArg(tc, index);
 324     int op = process->getSyscallArg(tc, index);
 325     int val = process->getSyscallArg(tc, index);
 326
 327     /*
 328      * Unsupported option that does not affect the correctness of the
 329      * application. This is a performance optimization utilized by Linux.
 330      */
 331     op &= ~OS::TGT_FUTEX_PRIVATE_FLAG;
 332
 333     FutexMap &futex_map = tc->getSystemPtr()->futexMap;
 334
 335     if (OS::TGT_FUTEX_WAIT == op) {
 336         // Ensure futex system call accessed atomically.
 337         BufferArg buf(uaddr, sizeof(int));
 338         buf.copyIn(tc->getMemProxy());
 339         int mem_val = *(int*)buf.bufferPtr();
 340
 341         /*
 342          * The value in memory at uaddr is not equal with the expected val
 343          * (a different thread must have changed it before the system call was
 344          * invoked). In this case, we need to throw an error.
 345          */
 346         if (val != mem_val)
 347             return -OS::TGT_EWOULDBLOCK;
 348
 349         futex_map.suspend(uaddr, process->tgid(), tc);
 350
 351         return 0;
 352     } else if (OS::TGT_FUTEX_WAKE == op) {
 353         return futex_map.wakeup(uaddr, process->tgid(), val);
 354     }
 355
 356     warn("futex: op %d not implemented; ignoring.", op);
 357     return -ENOSYS;
 358 }
 359
 360
 361 /// Pseudo Funcs  - These functions use a different return convension,
 362 /// returning a second value in a register other than the normal return register
 363 SyscallReturn pipePseudoFunc(SyscallDesc *desc, int num,
 364                              Process *process, ThreadContext *tc);
 365
 366 /// Target getpidPseudo() handler.
 367 SyscallReturn getpidPseudoFunc(SyscallDesc *desc, int num,
 368                                Process *p, ThreadContext *tc);
 369
 370 /// Target getuidPseudo() handler.
 371 SyscallReturn getuidPseudoFunc(SyscallDesc *desc, int num,
 372                                Process *p, ThreadContext *tc);
 373
 374 /// Target getgidPseudo() handler.
 375 SyscallReturn getgidPseudoFunc(SyscallDesc *desc, int num,
 376                                Process *p, ThreadContext *tc);
 377
 378
 379 /// A readable name for 1,000,000, for converting microseconds to seconds.
 380 const int one_million = 1000000;
 381 /// A readable name for 1,000,000,000, for converting nanoseconds to seconds.
 382 const int one_billion = 1000000000;
 383
 384 /// Approximate seconds since the epoch (1/1/1970).  About a billion,
 385 /// by my reckoning.  We want to keep this a constant (not use the
 386 /// real-world time) to keep simulations repeatable.
 387 const unsigned seconds_since_epoch = 1000000000;
 388
 389 /// Helper function to convert current elapsed time to seconds and
 390 /// microseconds.
 391 template <class T1, class T2>
 392 void
 393 getElapsedTimeMicro(T1 &sec, T2 &usec)
 394 {
 395     uint64_t elapsed_usecs = curTick() / SimClock::Int::us;
 396     sec = elapsed_usecs / one_million;
 397     usec = elapsed_usecs % one_million;
 398 }
 399
 400 /// Helper function to convert current elapsed time to seconds and
 401 /// nanoseconds.
 402 template <class T1, class T2>
 403 void
 404 getElapsedTimeNano(T1 &sec, T2 &nsec)
 405 {
 406     uint64_t elapsed_nsecs = curTick() / SimClock::Int::ns;
 407     sec = elapsed_nsecs / one_billion;
 408     nsec = elapsed_nsecs % one_billion;
 409 }
 410
 411 //////////////////////////////////////////////////////////////////////
 412 //
 413 // The following emulation functions are generic, but need to be
 414 // templated to account for differences in types, constants, etc.
 415 //
 416 //////////////////////////////////////////////////////////////////////
 417
 418     typedef struct statfs hst_statfs;
 419 #if NO_STAT64
 420     typedef struct stat hst_stat;
 421     typedef struct stat hst_stat64;
 422 #else
 423     typedef struct stat hst_stat;
 424     typedef struct stat64 hst_stat64;
 425 #endif
 426
 427 //// Helper function to convert a host stat buffer to a target stat
 428 //// buffer.  Also copies the target buffer out to the simulated
 429 //// memory space.  Used by stat(), fstat(), and lstat().
 430
 431 template <typename target_stat, typename host_stat>
 432 void
 433 convertStatBuf(target_stat &tgt, host_stat *host, bool fakeTTY = false)
 434 {
 435     using namespace TheISA;
 436
 437     if (fakeTTY)
 438         tgt->st_dev = 0xA;
 439     else
 440         tgt->st_dev = host->st_dev;
 441     tgt->st_dev = TheISA::htog(tgt->st_dev);
 442     tgt->st_ino = host->st_ino;
 443     tgt->st_ino = TheISA::htog(tgt->st_ino);
 444     tgt->st_mode = host->st_mode;
 445     if (fakeTTY) {
 446         // Claim to be a character device
 447         tgt->st_mode &= ~S_IFMT;    // Clear S_IFMT
 448         tgt->st_mode |= S_IFCHR;    // Set S_IFCHR
 449     }
 450     tgt->st_mode = TheISA::htog(tgt->st_mode);
 451     tgt->st_nlink = host->st_nlink;
 452     tgt->st_nlink = TheISA::htog(tgt->st_nlink);
 453     tgt->st_uid = host->st_uid;
 454     tgt->st_uid = TheISA::htog(tgt->st_uid);
 455     tgt->st_gid = host->st_gid;
 456     tgt->st_gid = TheISA::htog(tgt->st_gid);
 457     if (fakeTTY)
 458         tgt->st_rdev = 0x880d;
 459     else
 460         tgt->st_rdev = host->st_rdev;
 461     tgt->st_rdev = TheISA::htog(tgt->st_rdev);
 462     tgt->st_size = host->st_size;
 463     tgt->st_size = TheISA::htog(tgt->st_size);
 464     tgt->st_atimeX = host->st_atime;
 465     tgt->st_atimeX = TheISA::htog(tgt->st_atimeX);
 466     tgt->st_mtimeX = host->st_mtime;
 467     tgt->st_mtimeX = TheISA::htog(tgt->st_mtimeX);
 468     tgt->st_ctimeX = host->st_ctime;
 469     tgt->st_ctimeX = TheISA::htog(tgt->st_ctimeX);
 470     // Force the block size to be 8KB. This helps to ensure buffered io works
 471     // consistently across different hosts.
 472     tgt->st_blksize = 0x2000;
 473     tgt->st_blksize = TheISA::htog(tgt->st_blksize);
 474     tgt->st_blocks = host->st_blocks;
 475     tgt->st_blocks = TheISA::htog(tgt->st_blocks);
 476 }
 477
 478 // Same for stat64
 479
 480 template <typename target_stat, typename host_stat64>
 481 void
 482 convertStat64Buf(target_stat &tgt, host_stat64 *host, bool fakeTTY = false)
 483 {
 484     using namespace TheISA;
 485
 486     convertStatBuf<target_stat, host_stat64>(tgt, host, fakeTTY);
 487 #if defined(STAT_HAVE_NSEC)
 488     tgt->st_atime_nsec = host->st_atime_nsec;
 489     tgt->st_atime_nsec = TheISA::htog(tgt->st_atime_nsec);
 490     tgt->st_mtime_nsec = host->st_mtime_nsec;
 491     tgt->st_mtime_nsec = TheISA::htog(tgt->st_mtime_nsec);
 492     tgt->st_ctime_nsec = host->st_ctime_nsec;
 493     tgt->st_ctime_nsec = TheISA::htog(tgt->st_ctime_nsec);
 494 #else
 495     tgt->st_atime_nsec = 0;
 496     tgt->st_mtime_nsec = 0;
 497     tgt->st_ctime_nsec = 0;
 498 #endif
 499 }
 500
 501 // Here are a couple of convenience functions
 502 template<class OS>
 503 void
 504 copyOutStatBuf(SETranslatingPortProxy &mem, Addr addr,
 505                hst_stat *host, bool fakeTTY = false)
 506 {
 507     typedef TypedBufferArg<typename OS::tgt_stat> tgt_stat_buf;
 508     tgt_stat_buf tgt(addr);
 509     convertStatBuf<tgt_stat_buf, hst_stat>(tgt, host, fakeTTY);
 510     tgt.copyOut(mem);
 511 }
 512
 513 template<class OS>
 514 void
 515 copyOutStat64Buf(SETranslatingPortProxy &mem, Addr addr,
 516                  hst_stat64 *host, bool fakeTTY = false)
 517 {
 518     typedef TypedBufferArg<typename OS::tgt_stat64> tgt_stat_buf;
 519     tgt_stat_buf tgt(addr);
 520     convertStat64Buf<tgt_stat_buf, hst_stat64>(tgt, host, fakeTTY);
 521     tgt.copyOut(mem);
 522 }
 523
 524 template <class OS>
 525 void
 526 copyOutStatfsBuf(SETranslatingPortProxy &mem, Addr addr,
 527                  hst_statfs *host)
 528 {
 529     TypedBufferArg<typename OS::tgt_statfs> tgt(addr);
 530
 531     tgt->f_type = TheISA::htog(host->f_type);
 532 #if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__)
 533     tgt->f_bsize = TheISA::htog(host->f_iosize);
 534 #else
 535     tgt->f_bsize = TheISA::htog(host->f_bsize);
 536 #endif
 537     tgt->f_blocks = TheISA::htog(host->f_blocks);
 538     tgt->f_bfree = TheISA::htog(host->f_bfree);
 539     tgt->f_bavail = TheISA::htog(host->f_bavail);
 540     tgt->f_files = TheISA::htog(host->f_files);
 541     tgt->f_ffree = TheISA::htog(host->f_ffree);
 542     memcpy(&tgt->f_fsid, &host->f_fsid, sizeof(host->f_fsid));
 543 #if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__)
 544     tgt->f_namelen = TheISA::htog(host->f_namemax);
 545     tgt->f_frsize = TheISA::htog(host->f_bsize);
 546 #elif defined(__APPLE__)
 547     tgt->f_namelen = 0;
 548     tgt->f_frsize = 0;
 549 #else
 550     tgt->f_namelen = TheISA::htog(host->f_namelen);
 551     tgt->f_frsize = TheISA::htog(host->f_frsize);
 552 #endif
 553 #if defined(__linux__)
 554     memcpy(&tgt->f_spare, &host->f_spare, sizeof(host->f_spare));
 555 #else
 556     /*
 557      * The fields are different sizes per OS. Don't bother with
 558      * f_spare or f_reserved on non-Linux for now.
 559      */
 560     memset(&tgt->f_spare, 0, sizeof(tgt->f_spare));
 561 #endif
 562
 563     tgt.copyOut(mem);
 564 }
 565
 566 /// Target ioctl() handler.  For the most part, programs call ioctl()
 567 /// only to find out if their stdout is a tty, to determine whether to
 568 /// do line or block buffering.  We always claim that output fds are
 569 /// not TTYs to provide repeatable results.
 570 template <class OS>
 571 SyscallReturn
 572 ioctlFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc)
 573 {
 574     int index = 0;
 575     int tgt_fd = p->getSyscallArg(tc, index);
 576     unsigned req = p->getSyscallArg(tc, index);
 577
 578     DPRINTF(SyscallVerbose, "ioctl(%d, 0x%x, ...)\n", tgt_fd, req);
 579
 580     if (OS::isTtyReq(req))
 581         return -ENOTTY;
 582
 583     auto dfdp = std::dynamic_pointer_cast<DeviceFDEntry>((*p->fds)[tgt_fd]);
 584     if (!dfdp)
 585         return -EBADF;
 586
 587     /**
 588      * If the driver is valid, issue the ioctl through it. Otherwise,
 589      * there's an implicit assumption that the device is a TTY type and we
 590      * return that we do not have a valid TTY.
 591      */
 592     EmulatedDriver *emul_driver = dfdp->getDriver();
 593     if (emul_driver)
 594         return emul_driver->ioctl(p, tc, req);
 595
 596     /**
 597      * For lack of a better return code, return ENOTTY. Ideally, we should
 598      * return something better here, but at least we issue the warning.
 599      */
 600     warn("Unsupported ioctl call (return ENOTTY): ioctl(%d, 0x%x, ...) @ \n",
 601          tgt_fd, req, tc->pcState());
 602     return -ENOTTY;
 603 }
 604
 605 template <class OS>
 606 SyscallReturn
 607 openImpl(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc,
 608          bool isopenat)
 609 {
 610     int index = 0;
 611     int tgt_dirfd = -1;
 612
 613     /**
 614      * If using the openat variant, read in the target directory file
 615      * descriptor from the simulated process.
 616      */
 617     if (isopenat)
 618         tgt_dirfd = p->getSyscallArg(tc, index);
 619
 620     /**
 621      * Retrieve the simulated process' memory proxy and then read in the path
 622      * string from that memory space into the host's working memory space.
 623      */
 624     std::string path;
 625     if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index)))
 626         return -EFAULT;
 627
 628 #ifdef __CYGWIN32__
 629     int host_flags = O_BINARY;
 630 #else
 631     int host_flags = 0;
 632 #endif
 633     /**
 634      * Translate target flags into host flags. Flags exist which are not
 635      * ported between architectures which can cause check failures.
 636      */
 637     int tgt_flags = p->getSyscallArg(tc, index);
 638     for (int i = 0; i < OS::NUM_OPEN_FLAGS; i++) {
 639         if (tgt_flags & OS::openFlagTable[i].tgtFlag) {
 640             tgt_flags &= ~OS::openFlagTable[i].tgtFlag;
 641             host_flags |= OS::openFlagTable[i].hostFlag;
 642         }
 643     }
 644     if (tgt_flags) {
 645         warn("open%s: cannot decode flags 0x%x",
 646              isopenat ? "at" : "", tgt_flags);
 647     }
 648 #ifdef __CYGWIN32__
 649     host_flags |= O_BINARY;
 650 #endif
 651
 652     int mode = p->getSyscallArg(tc, index);
 653
 654     /**
 655      * If the simulated process called open or openat with AT_FDCWD specified,
 656      * take the current working directory value which was passed into the
 657      * process class as a Python parameter and append the current path to
 658      * create a full path.
 659      * Otherwise, openat with a valid target directory file descriptor has
 660      * been called. If the path option, which was passed in as a parameter,
 661      * is not absolute, retrieve the directory file descriptor's path and
 662      * prepend it to the path passed in as a parameter.
 663      * In every case, we should have a full path (which is relevant to the
 664      * host) to work with after this block has been passed.
 665      */
 666     if (!isopenat || (isopenat && tgt_dirfd == OS::TGT_AT_FDCWD)) {
 667         path = p->fullPath(path);
 668     } else if (!startswith(path, "/")) {
 669         std::shared_ptr<FDEntry> fdep = ((*p->fds)[tgt_dirfd]);
 670         auto ffdp = std::dynamic_pointer_cast<FileFDEntry>(fdep);
 671         if (!ffdp)
 672             return -EBADF;
 673         path.insert(0, ffdp->getFileName());
 674     }
 675
 676     /**
 677      * Since this is an emulated environment, we create pseudo file
 678      * descriptors for device requests that have been registered with
 679      * the process class through Python; this allows us to create a file
 680      * descriptor for subsequent ioctl or mmap calls.
 681      */
 682     if (startswith(path, "/dev/")) {
 683         std::string filename = path.substr(strlen("/dev/"));
 684         EmulatedDriver *drv = p->findDriver(filename);
 685         if (drv) {
 686             DPRINTF_SYSCALL(Verbose, "open%s: passing call to "
 687                             "driver open with path[%s]\n",
 688                             isopenat ? "at" : "", path.c_str());
 689             return drv->open(p, tc, mode, host_flags);
 690         }
 691         /**
 692          * Fall through here for pass through to host devices, such
 693          * as /dev/zero
 694          */
 695     }
 696
 697     /**
 698      * Some special paths and files cannot be called on the host and need
 699      * to be handled as special cases inside the simulator.
 700      * If the full path that was created above does not match any of the
 701      * special cases, pass it through to the open call on the host to let
 702      * the host open the file on our behalf.
 703      * If the host cannot open the file, return the host's error code back
 704      * through the system call to the simulated process.
 705      */
 706     int sim_fd = -1;
 707     std::vector<std::string> special_paths =
 708             { "/proc/", "/system/", "/sys/", "/platform/", "/etc/passwd" };
 709     for (auto entry : special_paths) {
 710         if (startswith(path, entry))
 711             sim_fd = OS::openSpecialFile(path, p, tc);
 712     }
 713     if (sim_fd == -1) {
 714         sim_fd = open(path.c_str(), host_flags, mode);
 715     }
 716     if (sim_fd == -1) {
 717         int local = -errno;
 718         DPRINTF_SYSCALL(Verbose, "open%s: failed -> path:%s\n",
 719                         isopenat ? "at" : "", path.c_str());
 720         return local;
 721     }
 722
 723     /**
 724      * The file was opened successfully and needs to be recorded in the
 725      * process' file descriptor array so that it can be retrieved later.
 726      * The target file descriptor that is chosen will be the lowest unused
 727      * file descriptor.
 728      * Return the indirect target file descriptor back to the simulated
 729      * process to act as a handle for the opened file.
 730      */
 731     auto ffdp = std::make_shared<FileFDEntry>(sim_fd, host_flags, path, 0);
 732     int tgt_fd = p->fds->allocFD(ffdp);
 733     DPRINTF_SYSCALL(Verbose, "open%s: sim_fd[%d], target_fd[%d] -> path:%s\n",
 734                     isopenat ? "at" : "", sim_fd, tgt_fd, path.c_str());
 735     return tgt_fd;
 736 }
 737
 738 /// Target open() handler.
 739 template <class OS>
 740 SyscallReturn
 741 openFunc(SyscallDesc *desc, int callnum, Process *process,
 742          ThreadContext *tc)
 743 {
 744     return openImpl<OS>(desc, callnum, process, tc, false);
 745 }
 746
 747 /// Target openat() handler.
 748 template <class OS>
 749 SyscallReturn
 750 openatFunc(SyscallDesc *desc, int callnum, Process *process,
 751            ThreadContext *tc)
 752 {
 753     return openImpl<OS>(desc, callnum, process, tc, true);
 754 }
 755
 756 /// Target unlinkat() handler.
 757 template <class OS>
 758 SyscallReturn
 759 unlinkatFunc(SyscallDesc *desc, int callnum, Process *process,
 760              ThreadContext *tc)
 761 {
 762     int index = 0;
 763     int dirfd = process->getSyscallArg(tc, index);
 764     if (dirfd != OS::TGT_AT_FDCWD)
 765         warn("unlinkat: first argument not AT_FDCWD; unlikely to work");
 766
 767     return unlinkHelper(desc, callnum, process, tc, 1);
 768 }
 769
 770 /// Target facessat() handler
 771 template <class OS>
 772 SyscallReturn
 773 faccessatFunc(SyscallDesc *desc, int callnum, Process *process,
 774               ThreadContext *tc)
 775 {
 776     int index = 0;
 777     int dirfd = process->getSyscallArg(tc, index);
 778     if (dirfd != OS::TGT_AT_FDCWD)
 779         warn("faccessat: first argument not AT_FDCWD; unlikely to work");
 780     return accessFunc(desc, callnum, process, tc, 1);
 781 }
 782
 783 /// Target readlinkat() handler
 784 template <class OS>
 785 SyscallReturn
 786 readlinkatFunc(SyscallDesc *desc, int callnum, Process *process,
 787                ThreadContext *tc)
 788 {
 789     int index = 0;
 790     int dirfd = process->getSyscallArg(tc, index);
 791     if (dirfd != OS::TGT_AT_FDCWD)
 792         warn("openat: first argument not AT_FDCWD; unlikely to work");
 793     return readlinkFunc(desc, callnum, process, tc, 1);
 794 }
 795
 796 /// Target renameat() handler.
 797 template <class OS>
 798 SyscallReturn
 799 renameatFunc(SyscallDesc *desc, int callnum, Process *process,
 800              ThreadContext *tc)
 801 {
 802     int index = 0;
 803
 804     int olddirfd = process->getSyscallArg(tc, index);
 805     if (olddirfd != OS::TGT_AT_FDCWD)
 806         warn("renameat: first argument not AT_FDCWD; unlikely to work");
 807
 808     std::string old_name;
 809
 810     if (!tc->getMemProxy().tryReadString(old_name,
 811                                          process->getSyscallArg(tc, index)))
 812         return -EFAULT;
 813
 814     int newdirfd = process->getSyscallArg(tc, index);
 815     if (newdirfd != OS::TGT_AT_FDCWD)
 816         warn("renameat: third argument not AT_FDCWD; unlikely to work");
 817
 818     std::string new_name;
 819
 820     if (!tc->getMemProxy().tryReadString(new_name,
 821                                          process->getSyscallArg(tc, index)))
 822         return -EFAULT;
 823
 824     // Adjust path for current working directory
 825     old_name = process->fullPath(old_name);
 826     new_name = process->fullPath(new_name);
 827
 828     int result = rename(old_name.c_str(), new_name.c_str());
 829     return (result == -1) ? -errno : result;
 830 }
 831
 832 /// Target sysinfo() handler.
 833 template <class OS>
 834 SyscallReturn
 835 sysinfoFunc(SyscallDesc *desc, int callnum, Process *process,
 836             ThreadContext *tc)
 837 {
 838
 839     int index = 0;
 840     TypedBufferArg<typename OS::tgt_sysinfo>
 841         sysinfo(process->getSyscallArg(tc, index));
 842
 843     sysinfo->uptime = seconds_since_epoch;
 844     sysinfo->totalram = process->system->memSize();
 845     sysinfo->mem_unit = 1;
 846
 847     sysinfo.copyOut(tc->getMemProxy());
 848
 849     return 0;
 850 }
 851
 852 /// Target chmod() handler.
 853 template <class OS>
 854 SyscallReturn
 855 chmodFunc(SyscallDesc *desc, int callnum, Process *process,
 856           ThreadContext *tc)
 857 {
 858     std::string path;
 859
 860     int index = 0;
 861     if (!tc->getMemProxy().tryReadString(path,
 862                 process->getSyscallArg(tc, index))) {
 863         return -EFAULT;
 864     }
 865
 866     uint32_t mode = process->getSyscallArg(tc, index);
 867     mode_t hostMode = 0;
 868
 869     // XXX translate mode flags via OS::something???
 870     hostMode = mode;
 871
 872     // Adjust path for current working directory
 873     path = process->fullPath(path);
 874
 875     // do the chmod
 876     int result = chmod(path.c_str(), hostMode);
 877     if (result < 0)
 878         return -errno;
 879
 880     return 0;
 881 }
 882
 883
 884 /// Target fchmod() handler.
 885 template <class OS>
 886 SyscallReturn
 887 fchmodFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc)
 888 {
 889     int index = 0;
 890     int tgt_fd = p->getSyscallArg(tc, index);
 891     uint32_t mode = p->getSyscallArg(tc, index);
 892
 893     auto ffdp = std::dynamic_pointer_cast<FileFDEntry>((*p->fds)[tgt_fd]);
 894     if (!ffdp)
 895         return -EBADF;
 896     int sim_fd = ffdp->getSimFD();
 897
 898     mode_t hostMode = mode;
 899
 900     int result = fchmod(sim_fd, hostMode);
 901
 902     return (result < 0) ? -errno : 0;
 903 }
 904
 905 /// Target mremap() handler.
 906 template <class OS>
 907 SyscallReturn
 908 mremapFunc(SyscallDesc *desc, int callnum, Process *process, ThreadContext *tc)
 909 {
 910     int index = 0;
 911     Addr start = process->getSyscallArg(tc, index);
 912     uint64_t old_length = process->getSyscallArg(tc, index);
 913     uint64_t new_length = process->getSyscallArg(tc, index);
 914     uint64_t flags = process->getSyscallArg(tc, index);
 915     uint64_t provided_address = 0;
 916     bool use_provided_address = flags & OS::TGT_MREMAP_FIXED;
 917
 918     if (use_provided_address)
 919         provided_address = process->getSyscallArg(tc, index);
 920
 921     if ((start % TheISA::PageBytes != 0) ||
 922         (provided_address % TheISA::PageBytes != 0)) {
 923         warn("mremap failing: arguments not page aligned");
 924         return -EINVAL;
 925     }
 926
 927     new_length = roundUp(new_length, TheISA::PageBytes);
 928
 929     if (new_length > old_length) {
 930         std::shared_ptr<MemState> mem_state = process->memState;
 931         Addr mmap_end = mem_state->getMmapEnd();
 932
 933         if ((start + old_length) == mmap_end &&
 934             (!use_provided_address || provided_address == start)) {
 935             uint64_t diff = new_length - old_length;
 936             process->allocateMem(mmap_end, diff);
 937             mem_state->setMmapEnd(mmap_end + diff);
 938             return start;
 939         } else {
 940             if (!use_provided_address && !(flags & OS::TGT_MREMAP_MAYMOVE)) {
 941                 warn("can't remap here and MREMAP_MAYMOVE flag not set\n");
 942                 return -ENOMEM;
 943             } else {
 944                 uint64_t new_start = use_provided_address ?
 945                     provided_address : mmap_end;
 946                 process->pTable->remap(start, old_length, new_start);
 947                 warn("mremapping to new vaddr %08p-%08p, adding %d\n",
 948                      new_start, new_start + new_length,
 949                      new_length - old_length);
 950                 // add on the remaining unallocated pages
 951                 process->allocateMem(new_start + old_length,
 952                                      new_length - old_length,
 953                                      use_provided_address /* clobber */);
 954                 if (!use_provided_address)
 955                     mem_state->setMmapEnd(mmap_end + new_length);
 956                 if (use_provided_address &&
 957                     new_start + new_length > mem_state->getMmapEnd()) {
 958                     // something fishy going on here, at least notify the user
 959                     // @todo: increase mmap_end?
 960                     warn("mmap region limit exceeded with MREMAP_FIXED\n");
 961                 }
 962                 warn("returning %08p as start\n", new_start);
 963                 return new_start;
 964             }
 965         }
 966     } else {
 967         if (use_provided_address && provided_address != start)
 968             process->pTable->remap(start, new_length, provided_address);
 969         process->pTable->unmap(start + new_length, old_length - new_length);
 970         return use_provided_address ? provided_address : start;
 971     }
 972 }
 973
 974 /// Target stat() handler.
 975 template <class OS>
 976 SyscallReturn
 977 statFunc(SyscallDesc *desc, int callnum, Process *process,
 978          ThreadContext *tc)
 979 {
 980     std::string path;
 981
 982     int index = 0;
 983     if (!tc->getMemProxy().tryReadString(path,
 984                 process->getSyscallArg(tc, index))) {
 985         return -EFAULT;
 986     }
 987     Addr bufPtr = process->getSyscallArg(tc, index);
 988
 989     // Adjust path for current working directory
 990     path = process->fullPath(path);
 991
 992     struct stat hostBuf;
 993     int result = stat(path.c_str(), &hostBuf);
 994
 995     if (result < 0)
 996         return -errno;
 997
 998     copyOutStatBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
 999
1000     return 0;
1001 }
1002
1003
1004 /// Target stat64() handler.
1005 template <class OS>
1006 SyscallReturn
1007 stat64Func(SyscallDesc *desc, int callnum, Process *process,
1008            ThreadContext *tc)
1009 {
1010     std::string path;
1011
1012     int index = 0;
1013     if (!tc->getMemProxy().tryReadString(path,
1014                 process->getSyscallArg(tc, index)))
1015         return -EFAULT;
1016     Addr bufPtr = process->getSyscallArg(tc, index);
1017
1018     // Adjust path for current working directory
1019     path = process->fullPath(path);
1020
1021 #if NO_STAT64
1022     struct stat  hostBuf;
1023     int result = stat(path.c_str(), &hostBuf);
1024 #else
1025     struct stat64 hostBuf;
1026     int result = stat64(path.c_str(), &hostBuf);
1027 #endif
1028
1029     if (result < 0)
1030         return -errno;
1031
1032     copyOutStat64Buf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
1033
1034     return 0;
1035 }
1036
1037
1038 /// Target fstatat64() handler.
1039 template <class OS>
1040 SyscallReturn
1041 fstatat64Func(SyscallDesc *desc, int callnum, Process *process,
1042               ThreadContext *tc)
1043 {
1044     int index = 0;
1045     int dirfd = process->getSyscallArg(tc, index);
1046     if (dirfd != OS::TGT_AT_FDCWD)
1047         warn("fstatat64: first argument not AT_FDCWD; unlikely to work");
1048
1049     std::string path;
1050     if (!tc->getMemProxy().tryReadString(path,
1051                 process->getSyscallArg(tc, index)))
1052         return -EFAULT;
1053     Addr bufPtr = process->getSyscallArg(tc, index);
1054
1055     // Adjust path for current working directory
1056     path = process->fullPath(path);
1057
1058 #if NO_STAT64
1059     struct stat  hostBuf;
1060     int result = stat(path.c_str(), &hostBuf);
1061 #else
1062     struct stat64 hostBuf;
1063     int result = stat64(path.c_str(), &hostBuf);
1064 #endif
1065
1066     if (result < 0)
1067         return -errno;
1068
1069     copyOutStat64Buf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
1070
1071     return 0;
1072 }
1073
1074
1075 /// Target fstat64() handler.
1076 template <class OS>
1077 SyscallReturn
1078 fstat64Func(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc)
1079 {
1080     int index = 0;
1081     int tgt_fd = p->getSyscallArg(tc, index);
1082     Addr bufPtr = p->getSyscallArg(tc, index);
1083
1084     auto ffdp = std::dynamic_pointer_cast<FileFDEntry>((*p->fds)[tgt_fd]);
1085     if (!ffdp)
1086         return -EBADF;
1087     int sim_fd = ffdp->getSimFD();
1088
1089 #if NO_STAT64
1090     struct stat  hostBuf;
1091     int result = fstat(sim_fd, &hostBuf);
1092 #else
1093     struct stat64  hostBuf;
1094     int result = fstat64(sim_fd, &hostBuf);
1095 #endif
1096
1097     if (result < 0)
1098         return -errno;
1099
1100     copyOutStat64Buf<OS>(tc->getMemProxy(), bufPtr, &hostBuf, (sim_fd == 1));
1101
1102     return 0;
1103 }
1104
1105
1106 /// Target lstat() handler.
1107 template <class OS>
1108 SyscallReturn
1109 lstatFunc(SyscallDesc *desc, int callnum, Process *process,
1110           ThreadContext *tc)
1111 {
1112     std::string path;
1113
1114     int index = 0;
1115     if (!tc->getMemProxy().tryReadString(path,
1116                 process->getSyscallArg(tc, index))) {
1117         return -EFAULT;
1118     }
1119     Addr bufPtr = process->getSyscallArg(tc, index);
1120
1121     // Adjust path for current working directory
1122     path = process->fullPath(path);
1123
1124     struct stat hostBuf;
1125     int result = lstat(path.c_str(), &hostBuf);
1126
1127     if (result < 0)
1128         return -errno;
1129
1130     copyOutStatBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
1131
1132     return 0;
1133 }
1134
1135 /// Target lstat64() handler.
1136 template <class OS>
1137 SyscallReturn
1138 lstat64Func(SyscallDesc *desc, int callnum, Process *process,
1139             ThreadContext *tc)
1140 {
1141     std::string path;
1142
1143     int index = 0;
1144     if (!tc->getMemProxy().tryReadString(path,
1145                 process->getSyscallArg(tc, index))) {
1146         return -EFAULT;
1147     }
1148     Addr bufPtr = process->getSyscallArg(tc, index);
1149
1150     // Adjust path for current working directory
1151     path = process->fullPath(path);
1152
1153 #if NO_STAT64
1154     struct stat hostBuf;
1155     int result = lstat(path.c_str(), &hostBuf);
1156 #else
1157     struct stat64 hostBuf;
1158     int result = lstat64(path.c_str(), &hostBuf);
1159 #endif
1160
1161     if (result < 0)
1162         return -errno;
1163
1164     copyOutStat64Buf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
1165
1166     return 0;
1167 }
1168
1169 /// Target fstat() handler.
1170 template <class OS>
1171 SyscallReturn
1172 fstatFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc)
1173 {
1174     int index = 0;
1175     int tgt_fd = p->getSyscallArg(tc, index);
1176     Addr bufPtr = p->getSyscallArg(tc, index);
1177
1178     DPRINTF_SYSCALL(Verbose, "fstat(%d, ...)\n", tgt_fd);
1179
1180     auto ffdp = std::dynamic_pointer_cast<FileFDEntry>((*p->fds)[tgt_fd]);
1181     if (!ffdp)
1182         return -EBADF;
1183     int sim_fd = ffdp->getSimFD();
1184
1185     struct stat hostBuf;
1186     int result = fstat(sim_fd, &hostBuf);
1187
1188     if (result < 0)
1189         return -errno;
1190
1191     copyOutStatBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf, (sim_fd == 1));
1192
1193     return 0;
1194 }
1195
1196
1197 /// Target statfs() handler.
1198 template <class OS>
1199 SyscallReturn
1200 statfsFunc(SyscallDesc *desc, int callnum, Process *process,
1201            ThreadContext *tc)
1202 {
1203 #if NO_STATFS
1204     warn("Host OS cannot support calls to statfs. Ignoring syscall");
1205 #else
1206     std::string path;
1207
1208     int index = 0;
1209     if (!tc->getMemProxy().tryReadString(path,
1210                 process->getSyscallArg(tc, index))) {
1211         return -EFAULT;
1212     }
1213     Addr bufPtr = process->getSyscallArg(tc, index);
1214
1215     // Adjust path for current working directory
1216     path = process->fullPath(path);
1217
1218     struct statfs hostBuf;
1219     int result = statfs(path.c_str(), &hostBuf);
1220
1221     if (result < 0)
1222         return -errno;
1223
1224     copyOutStatfsBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
1225 #endif
1226     return 0;
1227 }
1228
1229 template <class OS>
1230 SyscallReturn
1231 cloneFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc)
1232 {
1233     int index = 0;
1234     TheISA::IntReg flags = p->getSyscallArg(tc, index);
1235     TheISA::IntReg newStack = p->getSyscallArg(tc, index);
1236     Addr ptidPtr = p->getSyscallArg(tc, index);
1237     Addr ctidPtr = p->getSyscallArg(tc, index);
1238     Addr tlsPtr M5_VAR_USED = p->getSyscallArg(tc, index);
1239
1240     if (((flags & OS::TGT_CLONE_SIGHAND)&& !(flags & OS::TGT_CLONE_VM)) ||
1241         ((flags & OS::TGT_CLONE_THREAD) && !(flags & OS::TGT_CLONE_SIGHAND)) ||
1242         ((flags & OS::TGT_CLONE_FS)     &&  (flags & OS::TGT_CLONE_NEWNS)) ||
1243         ((flags & OS::TGT_CLONE_NEWIPC) &&  (flags & OS::TGT_CLONE_SYSVSEM)) ||
1244         ((flags & OS::TGT_CLONE_NEWPID) &&  (flags & OS::TGT_CLONE_THREAD)) ||
1245         ((flags & OS::TGT_CLONE_VM)     && !(newStack)))
1246         return -EINVAL;
1247
1248     ThreadContext *ctc;
1249     if (!(ctc = p->findFreeContext()))
1250         fatal("clone: no spare thread context in system");
1251
1252     /**
1253      * Note that ProcessParams is generated by swig and there are no other
1254      * examples of how to create anything but this default constructor. The
1255      * fields are manually initialized instead of passing parameters to the
1256      * constructor.
1257      */
1258     ProcessParams *pp = new ProcessParams();
1259     pp->executable.assign(*(new std::string(p->progName())));
1260     pp->cmd.push_back(*(new std::string(p->progName())));
1261     pp->system = p->system;
1262     pp->cwd.assign(p->getcwd());
1263     pp->input.assign("stdin");
1264     pp->output.assign("stdout");
1265     pp->errout.assign("stderr");
1266     pp->uid = p->uid();
1267     pp->euid = p->euid();
1268     pp->gid = p->gid();
1269     pp->egid = p->egid();
1270
1271     /* Find the first free PID that's less than the maximum */
1272     std::set<int> const& pids = p->system->PIDs;
1273     int temp_pid = *pids.begin();
1274     do {
1275         temp_pid++;
1276     } while (pids.find(temp_pid) != pids.end());
1277     if (temp_pid >= System::maxPID)
1278         fatal("temp_pid is too large: %d", temp_pid);
1279
1280     pp->pid = temp_pid;
1281     pp->ppid = (flags & OS::TGT_CLONE_THREAD) ? p->ppid() : p->pid();
1282     Process *cp = pp->create();
1283     delete pp;
1284
1285     Process *owner = ctc->getProcessPtr();
1286     ctc->setProcessPtr(cp);
1287     cp->assignThreadContext(ctc->contextId());
1288     owner->revokeThreadContext(ctc->contextId());
1289
1290     if (flags & OS::TGT_CLONE_PARENT_SETTID) {
1291         BufferArg ptidBuf(ptidPtr, sizeof(long));
1292         long *ptid = (long *)ptidBuf.bufferPtr();
1293         *ptid = cp->pid();
1294         ptidBuf.copyOut(tc->getMemProxy());
1295     }
1296
1297     cp->initState();
1298     p->clone(tc, ctc, cp, flags);
1299
1300     if (flags & OS::TGT_CLONE_THREAD) {
1301         delete cp->sigchld;
1302         cp->sigchld = p->sigchld;
1303     } else if (flags & OS::TGT_SIGCHLD) {
1304         *cp->sigchld = true;
1305     }
1306
1307     if (flags & OS::TGT_CLONE_CHILD_SETTID) {
1308         BufferArg ctidBuf(ctidPtr, sizeof(long));
1309         long *ctid = (long *)ctidBuf.bufferPtr();
1310         *ctid = cp->pid();
1311         ctidBuf.copyOut(ctc->getMemProxy());
1312     }
1313
1314     if (flags & OS::TGT_CLONE_CHILD_CLEARTID)
1315         cp->childClearTID = (uint64_t)ctidPtr;
1316
1317     ctc->clearArchRegs();
1318
1319 #if THE_ISA == ALPHA_ISA
1320     TheISA::copyMiscRegs(tc, ctc);
1321 #elif THE_ISA == SPARC_ISA
1322     TheISA::copyRegs(tc, ctc);
1323     ctc->setIntReg(TheISA::NumIntArchRegs + 6, 0);
1324     ctc->setIntReg(TheISA::NumIntArchRegs + 4, 0);
1325     ctc->setIntReg(TheISA::NumIntArchRegs + 3, TheISA::NWindows - 2);
1326     ctc->setIntReg(TheISA::NumIntArchRegs + 5, TheISA::NWindows);
1327     ctc->setMiscReg(TheISA::MISCREG_CWP, 0);
1328     ctc->setIntReg(TheISA::NumIntArchRegs + 7, 0);
1329     ctc->setMiscRegNoEffect(TheISA::MISCREG_TL, 0);
1330     ctc->setMiscReg(TheISA::MISCREG_ASI, TheISA::ASI_PRIMARY);
1331     for (int y = 8; y < 32; y++)
1332         ctc->setIntReg(y, tc->readIntReg(y));
1333 #elif THE_ISA == ARM_ISA or THE_ISA == X86_ISA
1334     TheISA::copyRegs(tc, ctc);
1335 #endif
1336
1337 #if THE_ISA == X86_ISA
1338     if (flags & OS::TGT_CLONE_SETTLS) {
1339         ctc->setMiscRegNoEffect(TheISA::MISCREG_FS_BASE, tlsPtr);
1340         ctc->setMiscRegNoEffect(TheISA::MISCREG_FS_EFF_BASE, tlsPtr);
1341     }
1342 #endif
1343
1344     if (newStack)
1345         ctc->setIntReg(TheISA::StackPointerReg, newStack);
1346
1347     cp->setSyscallReturn(ctc, 0);
1348
1349 #if THE_ISA == ALPHA_ISA
1350     ctc->setIntReg(TheISA::SyscallSuccessReg, 0);
1351 #elif THE_ISA == SPARC_ISA
1352     tc->setIntReg(TheISA::SyscallPseudoReturnReg, 0);
1353     ctc->setIntReg(TheISA::SyscallPseudoReturnReg, 1);
1354 #endif
1355
1356     ctc->pcState(tc->nextInstAddr());
1357     ctc->activate();
1358
1359     return cp->pid();
1360 }
1361
1362 /// Target fstatfs() handler.
1363 template <class OS>
1364 SyscallReturn
1365 fstatfsFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc)
1366 {
1367     int index = 0;
1368     int tgt_fd = p->getSyscallArg(tc, index);
1369     Addr bufPtr = p->getSyscallArg(tc, index);
1370
1371     auto ffdp = std::dynamic_pointer_cast<FileFDEntry>((*p->fds)[tgt_fd]);
1372     if (!ffdp)
1373         return -EBADF;
1374     int sim_fd = ffdp->getSimFD();
1375
1376     struct statfs hostBuf;
1377     int result = fstatfs(sim_fd, &hostBuf);
1378
1379     if (result < 0)
1380         return -errno;
1381
1382     copyOutStatfsBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
1383
1384     return 0;
1385 }
1386
1387
1388 /// Target writev() handler.
1389 template <class OS>
1390 SyscallReturn
1391 writevFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc)
1392 {
1393     int index = 0;
1394     int tgt_fd = p->getSyscallArg(tc, index);
1395
1396     auto hbfdp = std::dynamic_pointer_cast<HBFDEntry>((*p->fds)[tgt_fd]);
1397     if (!hbfdp)
1398         return -EBADF;
1399     int sim_fd = hbfdp->getSimFD();
1400
1401     SETranslatingPortProxy &prox = tc->getMemProxy();
1402     uint64_t tiov_base = p->getSyscallArg(tc, index);
1403     size_t count = p->getSyscallArg(tc, index);
1404     struct iovec hiov[count];
1405     for (size_t i = 0; i < count; ++i) {
1406         typename OS::tgt_iovec tiov;
1407
1408         prox.readBlob(tiov_base + i*sizeof(typename OS::tgt_iovec),
1409                       (uint8_t*)&tiov, sizeof(typename OS::tgt_iovec));
1410         hiov[i].iov_len = TheISA::gtoh(tiov.iov_len);
1411         hiov[i].iov_base = new char [hiov[i].iov_len];
1412         prox.readBlob(TheISA::gtoh(tiov.iov_base), (uint8_t *)hiov[i].iov_base,
1413                       hiov[i].iov_len);
1414     }
1415
1416     int result = writev(sim_fd, hiov, count);
1417
1418     for (size_t i = 0; i < count; ++i)
1419         delete [] (char *)hiov[i].iov_base;
1420
1421     if (result < 0)
1422         return -errno;
1423
1424     return result;
1425 }
1426
1427 /// Real mmap handler.
1428 template <class OS>
1429 SyscallReturn
1430 mmapImpl(SyscallDesc *desc, int num, Process *p, ThreadContext *tc,
1431          bool is_mmap2)
1432 {
1433     int index = 0;
1434     Addr start = p->getSyscallArg(tc, index);
1435     uint64_t length = p->getSyscallArg(tc, index);
1436     int prot = p->getSyscallArg(tc, index);
1437     int tgt_flags = p->getSyscallArg(tc, index);
1438     int tgt_fd = p->getSyscallArg(tc, index);
1439     int offset = p->getSyscallArg(tc, index);
1440
1441     if (is_mmap2)
1442         offset *= TheISA::PageBytes;
1443
1444     if (start & (TheISA::PageBytes - 1) ||
1445         offset & (TheISA::PageBytes - 1) ||
1446         (tgt_flags & OS::TGT_MAP_PRIVATE &&
1447          tgt_flags & OS::TGT_MAP_SHARED) ||
1448         (!(tgt_flags & OS::TGT_MAP_PRIVATE) &&
1449          !(tgt_flags & OS::TGT_MAP_SHARED)) ||
1450         !length) {
1451         return -EINVAL;
1452     }
1453
1454     if ((prot & PROT_WRITE) && (tgt_flags & OS::TGT_MAP_SHARED)) {
1455         // With shared mmaps, there are two cases to consider:
1456         // 1) anonymous: writes should modify the mapping and this should be
1457         // visible to observers who share the mapping. Currently, it's
1458         // difficult to update the shared mapping because there's no
1459         // structure which maintains information about the which virtual
1460         // memory areas are shared. If that structure existed, it would be
1461         // possible to make the translations point to the same frames.
1462         // 2) file-backed: writes should modify the mapping and the file
1463         // which is backed by the mapping. The shared mapping problem is the
1464         // same as what was mentioned about the anonymous mappings. For
1465         // file-backed mappings, the writes to the file are difficult
1466         // because it requires syncing what the mapping holds with the file
1467         // that resides on the host system. So, any write on a real system
1468         // would cause the change to be propagated to the file mapping at
1469         // some point in the future (the inode is tracked along with the
1470         // mapping). This isn't guaranteed to always happen, but it usually
1471         // works well enough. The guarantee is provided by the msync system
1472         // call. We could force the change through with shared mappings with
1473         // a call to msync, but that again would require more information
1474         // than we currently maintain.
1475         warn("mmap: writing to shared mmap region is currently "
1476              "unsupported. The write succeeds on the target, but it "
1477              "will not be propagated to the host or shared mappings");
1478     }
1479
1480     length = roundUp(length, TheISA::PageBytes);
1481
1482     int sim_fd = -1;
1483     uint8_t *pmap = nullptr;
1484     if (!(tgt_flags & OS::TGT_MAP_ANONYMOUS)) {
1485         std::shared_ptr<FDEntry> fdep = (*p->fds)[tgt_fd];
1486
1487         auto dfdp = std::dynamic_pointer_cast<DeviceFDEntry>(fdep);
1488         if (dfdp) {
1489             EmulatedDriver *emul_driver = dfdp->getDriver();
1490             return emul_driver->mmap(p, tc, start, length, prot,
1491                                      tgt_flags, tgt_fd, offset);
1492         }
1493
1494         auto ffdp = std::dynamic_pointer_cast<FileFDEntry>(fdep);
1495         if (!ffdp)
1496             return -EBADF;
1497         sim_fd = ffdp->getSimFD();
1498
1499         pmap = (decltype(pmap))mmap(nullptr, length, PROT_READ, MAP_PRIVATE,
1500                                     sim_fd, offset);
1501
1502         if (pmap == (decltype(pmap))-1) {
1503             warn("mmap: failed to map file into host address space");
1504             return -errno;
1505         }
1506     }
1507
1508     // Extend global mmap region if necessary. Note that we ignore the
1509     // start address unless MAP_FIXED is specified.
1510     if (!(tgt_flags & OS::TGT_MAP_FIXED)) {
1511         std::shared_ptr<MemState> mem_state = p->memState;
1512         Addr mmap_end = mem_state->getMmapEnd();
1513
1514         start = p->mmapGrowsDown() ? mmap_end - length : mmap_end;
1515         mmap_end = p->mmapGrowsDown() ? start : mmap_end + length;
1516
1517         mem_state->setMmapEnd(mmap_end);
1518     }
1519
1520     DPRINTF_SYSCALL(Verbose, " mmap range is 0x%x - 0x%x\n",
1521                     start, start + length - 1);
1522
1523     // We only allow mappings to overwrite existing mappings if
1524     // TGT_MAP_FIXED is set. Otherwise it shouldn't be a problem
1525     // because we ignore the start hint if TGT_MAP_FIXED is not set.
1526     int clobber = tgt_flags & OS::TGT_MAP_FIXED;
1527     if (clobber) {
1528         for (auto tc : p->system->threadContexts) {
1529             // If we might be overwriting old mappings, we need to
1530             // invalidate potentially stale mappings out of the TLBs.
1531             tc->getDTBPtr()->flushAll();
1532             tc->getITBPtr()->flushAll();
1533         }
1534     }
1535
1536     // Allocate physical memory and map it in. If the page table is already
1537     // mapped and clobber is not set, the simulator will issue throw a
1538     // fatal and bail out of the simulation.
1539     p->allocateMem(start, length, clobber);
1540
1541     // Transfer content into target address space.
1542     SETranslatingPortProxy &tp = tc->getMemProxy();
1543     if (tgt_flags & OS::TGT_MAP_ANONYMOUS) {
1544         // In general, we should zero the mapped area for anonymous mappings,
1545         // with something like:
1546         //     tp.memsetBlob(start, 0, length);
1547         // However, given that we don't support sparse mappings, and
1548         // some applications can map a couple of gigabytes of space
1549         // (intending sparse usage), that can get painfully expensive.
1550         // Fortunately, since we don't properly implement munmap either,
1551         // there's no danger of remapping used memory, so for now all
1552         // newly mapped memory should already be zeroed so we can skip it.
1553     } else {
1554         // It is possible to mmap an area larger than a file, however
1555         // accessing unmapped portions the system triggers a "Bus error"
1556         // on the host. We must know when to stop copying the file from
1557         // the host into the target address space.
1558         struct stat file_stat;
1559         if (fstat(sim_fd, &file_stat) > 0)
1560             fatal("mmap: cannot stat file");
1561
1562         // Copy the portion of the file that is resident. This requires
1563         // checking both the mmap size and the filesize that we are
1564         // trying to mmap into this space; the mmap size also depends
1565         // on the specified offset into the file.
1566         uint64_t size = std::min((uint64_t)file_stat.st_size - offset,
1567                                  length);
1568         tp.writeBlob(start, pmap, size);
1569
1570         // Cleanup the mmap region before exiting this function.
1571         munmap(pmap, length);
1572
1573         // Maintain the symbol table for dynamic executables.
1574         // The loader will call mmap to map the images into its address
1575         // space and we intercept that here. We can verify that we are
1576         // executing inside the loader by checking the program counter value.
1577         // XXX: with multiprogrammed workloads or multi-node configurations,
1578         // this will not work since there is a single global symbol table.
1579         ObjectFile *interpreter = p->getInterpreter();
1580         if (interpreter) {
1581             Addr text_start = interpreter->textBase();
1582             Addr text_end = text_start + interpreter->textSize();
1583
1584             Addr pc = tc->pcState().pc();
1585
1586             if (pc >= text_start && pc < text_end) {
1587                 std::shared_ptr<FDEntry> fdep = (*p->fds)[tgt_fd];
1588                 auto ffdp = std::dynamic_pointer_cast<FileFDEntry>(fdep);
1589                 ObjectFile *lib = createObjectFile(ffdp->getFileName());
1590
1591                 if (lib) {
1592                     lib->loadAllSymbols(debugSymbolTable,
1593                                         lib->textBase(), start);
1594                 }
1595             }
1596         }
1597
1598         // Note that we do not zero out the remainder of the mapping. This
1599         // is done by a real system, but it probably will not affect
1600         // execution (hopefully).
1601     }
1602
1603     return start;
1604 }
1605
1606 template <class OS>
1607 SyscallReturn
1608 pwrite64Func(SyscallDesc *desc, int num, Process *p, ThreadContext *tc)
1609 {
1610     int index = 0;
1611     int tgt_fd = p->getSyscallArg(tc, index);
1612     Addr bufPtr = p->getSyscallArg(tc, index);
1613     int nbytes = p->getSyscallArg(tc, index);
1614     int offset = p->getSyscallArg(tc, index);
1615
1616     auto ffdp = std::dynamic_pointer_cast<FileFDEntry>((*p->fds)[tgt_fd]);
1617     if (!ffdp)
1618         return -EBADF;
1619     int sim_fd = ffdp->getSimFD();
1620
1621     BufferArg bufArg(bufPtr, nbytes);
1622     bufArg.copyIn(tc->getMemProxy());
1623
1624     int bytes_written = pwrite(sim_fd, bufArg.bufferPtr(), nbytes, offset);
1625
1626     return (bytes_written == -1) ? -errno : bytes_written;
1627 }
1628
1629 /// Target mmap() handler.
1630 template <class OS>
1631 SyscallReturn
1632 mmapFunc(SyscallDesc *desc, int num, Process *p, ThreadContext *tc)
1633 {
1634     return mmapImpl<OS>(desc, num, p, tc, false);
1635 }
1636
1637 /// Target mmap2() handler.
1638 template <class OS>
1639 SyscallReturn
1640 mmap2Func(SyscallDesc *desc, int num, Process *p, ThreadContext *tc)
1641 {
1642     return mmapImpl<OS>(desc, num, p, tc, true);
1643 }
1644
1645 /// Target getrlimit() handler.
1646 template <class OS>
1647 SyscallReturn
1648 getrlimitFunc(SyscallDesc *desc, int callnum, Process *process,
1649               ThreadContext *tc)
1650 {
1651     int index = 0;
1652     unsigned resource = process->getSyscallArg(tc, index);
1653     TypedBufferArg<typename OS::rlimit> rlp(process->getSyscallArg(tc, index));
1654
1655     switch (resource) {
1656       case OS::TGT_RLIMIT_STACK:
1657         // max stack size in bytes: make up a number (8MB for now)
1658         rlp->rlim_cur = rlp->rlim_max = 8 * 1024 * 1024;
1659         rlp->rlim_cur = TheISA::htog(rlp->rlim_cur);
1660         rlp->rlim_max = TheISA::htog(rlp->rlim_max);
1661         break;
1662
1663       case OS::TGT_RLIMIT_DATA:
1664         // max data segment size in bytes: make up a number
1665         rlp->rlim_cur = rlp->rlim_max = 256 * 1024 * 1024;
1666         rlp->rlim_cur = TheISA::htog(rlp->rlim_cur);
1667         rlp->rlim_max = TheISA::htog(rlp->rlim_max);
1668         break;
1669
1670       default:
1671         warn("getrlimit: unimplemented resource %d", resource);
1672         return -EINVAL;
1673         break;
1674     }
1675
1676     rlp.copyOut(tc->getMemProxy());
1677     return 0;
1678 }
1679
1680 /// Target clock_gettime() function.
1681 template <class OS>
1682 SyscallReturn
1683 clock_gettimeFunc(SyscallDesc *desc, int num, Process *p, ThreadContext *tc)
1684 {
1685     int index = 1;
1686     //int clk_id = p->getSyscallArg(tc, index);
1687     TypedBufferArg<typename OS::timespec> tp(p->getSyscallArg(tc, index));
1688
1689     getElapsedTimeNano(tp->tv_sec, tp->tv_nsec);
1690     tp->tv_sec += seconds_since_epoch;
1691     tp->tv_sec = TheISA::htog(tp->tv_sec);
1692     tp->tv_nsec = TheISA::htog(tp->tv_nsec);
1693
1694     tp.copyOut(tc->getMemProxy());
1695
1696     return 0;
1697 }
1698
1699 /// Target clock_getres() function.
1700 template <class OS>
1701 SyscallReturn
1702 clock_getresFunc(SyscallDesc *desc, int num, Process *p, ThreadContext *tc)
1703 {
1704     int index = 1;
1705     TypedBufferArg<typename OS::timespec> tp(p->getSyscallArg(tc, index));
1706
1707     // Set resolution at ns, which is what clock_gettime() returns
1708     tp->tv_sec = 0;
1709     tp->tv_nsec = 1;
1710
1711     tp.copyOut(tc->getMemProxy());
1712
1713     return 0;
1714 }
1715
1716 /// Target gettimeofday() handler.
1717 template <class OS>
1718 SyscallReturn
1719 gettimeofdayFunc(SyscallDesc *desc, int callnum, Process *process,
1720                  ThreadContext *tc)
1721 {
1722     int index = 0;
1723     TypedBufferArg<typename OS::timeval> tp(process->getSyscallArg(tc, index));
1724
1725     getElapsedTimeMicro(tp->tv_sec, tp->tv_usec);
1726     tp->tv_sec += seconds_since_epoch;
1727     tp->tv_sec = TheISA::htog(tp->tv_sec);
1728     tp->tv_usec = TheISA::htog(tp->tv_usec);
1729
1730     tp.copyOut(tc->getMemProxy());
1731
1732     return 0;
1733 }
1734
1735
1736 /// Target utimes() handler.
1737 template <class OS>
1738 SyscallReturn
1739 utimesFunc(SyscallDesc *desc, int callnum, Process *process,
1740            ThreadContext *tc)
1741 {
1742     std::string path;
1743
1744     int index = 0;
1745     if (!tc->getMemProxy().tryReadString(path,
1746                 process->getSyscallArg(tc, index))) {
1747         return -EFAULT;
1748     }
1749
1750     TypedBufferArg<typename OS::timeval [2]>
1751         tp(process->getSyscallArg(tc, index));
1752     tp.copyIn(tc->getMemProxy());
1753
1754     struct timeval hostTimeval[2];
1755     for (int i = 0; i < 2; ++i) {
1756         hostTimeval[i].tv_sec = TheISA::gtoh((*tp)[i].tv_sec);
1757         hostTimeval[i].tv_usec = TheISA::gtoh((*tp)[i].tv_usec);
1758     }
1759
1760     // Adjust path for current working directory
1761     path = process->fullPath(path);
1762
1763     int result = utimes(path.c_str(), hostTimeval);
1764
1765     if (result < 0)
1766         return -errno;
1767
1768     return 0;
1769 }
1770
1771 template <class OS>
1772 SyscallReturn
1773 execveFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc)
1774 {
1775     desc->setFlags(0);
1776
1777     int index = 0;
1778     std::string path;
1779     SETranslatingPortProxy & mem_proxy = tc->getMemProxy();
1780     if (!mem_proxy.tryReadString(path, p->getSyscallArg(tc, index)))
1781         return -EFAULT;
1782
1783     if (access(path.c_str(), F_OK) == -1)
1784         return -EACCES;
1785
1786     auto read_in = [](std::vector<std::string> & vect,
1787                       SETranslatingPortProxy & mem_proxy,
1788                       Addr mem_loc)
1789     {
1790         for (int inc = 0; ; inc++) {
1791             BufferArg b((mem_loc + sizeof(Addr) * inc), sizeof(Addr));
1792             b.copyIn(mem_proxy);
1793
1794             if (!*(Addr*)b.bufferPtr())
1795                 break;
1796
1797             vect.push_back(std::string());
1798             mem_proxy.tryReadString(vect[inc], *(Addr*)b.bufferPtr());
1799         }
1800     };
1801
1802     /**
1803      * Note that ProcessParams is generated by swig and there are no other
1804      * examples of how to create anything but this default constructor. The
1805      * fields are manually initialized instead of passing parameters to the
1806      * constructor.
1807      */
1808     ProcessParams *pp = new ProcessParams();
1809     pp->executable = path;
1810     Addr argv_mem_loc = p->getSyscallArg(tc, index);
1811     read_in(pp->cmd, mem_proxy, argv_mem_loc);
1812     Addr envp_mem_loc = p->getSyscallArg(tc, index);
1813     read_in(pp->env, mem_proxy, envp_mem_loc);
1814     pp->uid = p->uid();
1815     pp->egid = p->egid();
1816     pp->euid = p->euid();
1817     pp->gid = p->gid();
1818     pp->ppid = p->ppid();
1819     pp->pid = p->pid();
1820     pp->input.assign("cin");
1821     pp->output.assign("cout");
1822     pp->errout.assign("cerr");
1823     pp->cwd.assign(p->getcwd());
1824     pp->system = p->system;
1825     /**
1826      * Prevent process object creation with identical PIDs (which will trip
1827      * a fatal check in Process constructor). The execve call is supposed to
1828      * take over the currently executing process' identity but replace
1829      * whatever it is doing with a new process image. Instead of hijacking
1830      * the process object in the simulator, we create a new process object
1831      * and bind to the previous process' thread below (hijacking the thread).
1832      */
1833     p->system->PIDs.erase(p->pid());
1834     Process *new_p = pp->create();
1835     delete pp;
1836
1837     /**
1838      * Work through the file descriptor array and close any files marked
1839      * close-on-exec.
1840      */
1841     new_p->fds = p->fds;
1842     for (int i = 0; i < new_p->fds->getSize(); i++) {
1843         std::shared_ptr<FDEntry> fdep = (*new_p->fds)[i];
1844         if (fdep && fdep->getCOE())
1845             new_p->fds->closeFDEntry(i);
1846     }
1847
1848     *new_p->sigchld = true;
1849
1850     delete p;
1851     tc->clearArchRegs();
1852     tc->setProcessPtr(new_p);
1853     new_p->assignThreadContext(tc->contextId());
1854     new_p->initState();
1855     tc->activate();
1856     TheISA::PCState pcState = tc->pcState();
1857     tc->setNPC(pcState.instAddr());
1858
1859     desc->setFlags(SyscallDesc::SuppressReturnValue);
1860     return 0;
1861 }
1862
1863 /// Target getrusage() function.
1864 template <class OS>
1865 SyscallReturn
1866 getrusageFunc(SyscallDesc *desc, int callnum, Process *process,
1867               ThreadContext *tc)
1868 {
1869     int index = 0;
1870     int who = process->getSyscallArg(tc, index); // THREAD, SELF, or CHILDREN
1871     TypedBufferArg<typename OS::rusage> rup(process->getSyscallArg(tc, index));
1872
1873     rup->ru_utime.tv_sec = 0;
1874     rup->ru_utime.tv_usec = 0;
1875     rup->ru_stime.tv_sec = 0;
1876     rup->ru_stime.tv_usec = 0;
1877     rup->ru_maxrss = 0;
1878     rup->ru_ixrss = 0;
1879     rup->ru_idrss = 0;
1880     rup->ru_isrss = 0;
1881     rup->ru_minflt = 0;
1882     rup->ru_majflt = 0;
1883     rup->ru_nswap = 0;
1884     rup->ru_inblock = 0;
1885     rup->ru_oublock = 0;
1886     rup->ru_msgsnd = 0;
1887     rup->ru_msgrcv = 0;
1888     rup->ru_nsignals = 0;
1889     rup->ru_nvcsw = 0;
1890     rup->ru_nivcsw = 0;
1891
1892     switch (who) {
1893       case OS::TGT_RUSAGE_SELF:
1894         getElapsedTimeMicro(rup->ru_utime.tv_sec, rup->ru_utime.tv_usec);
1895         rup->ru_utime.tv_sec = TheISA::htog(rup->ru_utime.tv_sec);
1896         rup->ru_utime.tv_usec = TheISA::htog(rup->ru_utime.tv_usec);
1897         break;
1898
1899       case OS::TGT_RUSAGE_CHILDREN:
1900         // do nothing.  We have no child processes, so they take no time.
1901         break;
1902
1903       default:
1904         // don't really handle THREAD or CHILDREN, but just warn and
1905         // plow ahead
1906         warn("getrusage() only supports RUSAGE_SELF.  Parameter %d ignored.",
1907              who);
1908     }
1909
1910     rup.copyOut(tc->getMemProxy());
1911
1912     return 0;
1913 }
1914
1915 /// Target times() function.
1916 template <class OS>
1917 SyscallReturn
1918 timesFunc(SyscallDesc *desc, int callnum, Process *process,
1919           ThreadContext *tc)
1920 {
1921     int index = 0;
1922     TypedBufferArg<typename OS::tms> bufp(process->getSyscallArg(tc, index));
1923
1924     // Fill in the time structure (in clocks)
1925     int64_t clocks = curTick() * OS::M5_SC_CLK_TCK / SimClock::Int::s;
1926     bufp->tms_utime = clocks;
1927     bufp->tms_stime = 0;
1928     bufp->tms_cutime = 0;
1929     bufp->tms_cstime = 0;
1930
1931     // Convert to host endianness
1932     bufp->tms_utime = TheISA::htog(bufp->tms_utime);
1933
1934     // Write back
1935     bufp.copyOut(tc->getMemProxy());
1936
1937     // Return clock ticks since system boot
1938     return clocks;
1939 }
1940
1941 /// Target time() function.
1942 template <class OS>
1943 SyscallReturn
1944 timeFunc(SyscallDesc *desc, int callnum, Process *process, ThreadContext *tc)
1945 {
1946     typename OS::time_t sec, usec;
1947     getElapsedTimeMicro(sec, usec);
1948     sec += seconds_since_epoch;
1949
1950     int index = 0;
1951     Addr taddr = (Addr)process->getSyscallArg(tc, index);
1952     if (taddr != 0) {
1953         typename OS::time_t t = sec;
1954         t = TheISA::htog(t);
1955         SETranslatingPortProxy &p = tc->getMemProxy();
1956         p.writeBlob(taddr, (uint8_t*)&t, (int)sizeof(typename OS::time_t));
1957     }
1958     return sec;
1959 }
1960
1961 template <class OS>
1962 SyscallReturn
1963 tgkillFunc(SyscallDesc *desc, int num, Process *process, ThreadContext *tc)
1964 {
1965     int index = 0;
1966     int tgid = process->getSyscallArg(tc, index);
1967     int tid = process->getSyscallArg(tc, index);
1968     int sig = process->getSyscallArg(tc, index);
1969
1970     /**
1971      * This system call is intended to allow killing a specific thread
1972      * within an arbitrary thread group if sanctioned with permission checks.
1973      * It's usually true that threads share the termination signal as pointed
1974      * out by the pthread_kill man page and this seems to be the intended
1975      * usage. Due to this being an emulated environment, assume the following:
1976      * Threads are allowed to call tgkill because the EUID for all threads
1977      * should be the same. There is no signal handling mechanism for kernel
1978      * registration of signal handlers since signals are poorly supported in
1979      * emulation mode. Since signal handlers cannot be registered, all
1980      * threads within in a thread group must share the termination signal.
1981      * We never exhaust PIDs so there's no chance of finding the wrong one
1982      * due to PID rollover.
1983      */
1984
1985     System *sys = tc->getSystemPtr();
1986     Process *tgt_proc = nullptr;
1987     for (int i = 0; i < sys->numContexts(); i++) {
1988         Process *temp = sys->threadContexts[i]->getProcessPtr();
1989         if (temp->pid() == tid) {
1990             tgt_proc = temp;
1991             break;
1992         }
1993     }
1994
1995     if (sig != 0 || sig != OS::TGT_SIGABRT)
1996         return -EINVAL;
1997
1998     if (tgt_proc == nullptr)
1999         return -ESRCH;
2000
2001     if (tgid != -1 && tgt_proc->tgid() != tgid)
2002         return -ESRCH;
2003
2004     if (sig == OS::TGT_SIGABRT)
2005         exitGroupFunc(desc, 252, process, tc);
2006
2007     return 0;
2008 }
2009
2010
2011 #endif // __SIM_SYSCALL_EMUL_HH__