syscall_emul.hh revision 14129
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/// 57/// @file syscall_emul.hh 58/// 59/// This file defines objects used to emulate syscalls from the target 60/// application on the host machine. 61 62#if defined(__linux__) 63#include <sys/eventfd.h> 64#include <sys/statfs.h> 65 66#else 67#include <sys/mount.h> 68 69#endif 70 71#ifdef __CYGWIN32__ 72#include <sys/fcntl.h> 73 74#endif 75#include <fcntl.h> 76#include <net/if.h> 77#include <poll.h> 78#include <sys/ioctl.h> 79#include <sys/mman.h> 80#include <sys/socket.h> 81#include <sys/stat.h> 82#include <sys/time.h> 83#include <sys/types.h> 84#include <sys/uio.h> 85#include <unistd.h> 86 87#include <cerrno> 88#include <memory> 89#include <string> 90 91#include "arch/generic/tlb.hh" 92#include "arch/utility.hh" 93#include "base/intmath.hh" 94#include "base/loader/object_file.hh" 95#include "base/logging.hh" 96#include "base/trace.hh" 97#include "base/types.hh" 98#include "config/the_isa.hh" 99#include "cpu/base.hh" 100#include "cpu/thread_context.hh" 101#include "mem/page_table.hh" 102#include "params/Process.hh" 103#include "sim/emul_driver.hh" 104#include "sim/futex_map.hh" 105#include "sim/process.hh" 106#include "sim/syscall_debug_macros.hh" 107#include "sim/syscall_desc.hh" 108#include "sim/syscall_emul_buf.hh" 109#include "sim/syscall_return.hh" 110 111#if defined(__APPLE__) && defined(__MACH__) && !defined(CMSG_ALIGN) 112#define CMSG_ALIGN(len) (((len) + sizeof(size_t) - 1) & ~(sizeof(size_t) - 1)) 113#endif 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 123void warnUnsupportedOS(std::string syscall_name); 124 125/// Handler for unimplemented syscalls that we haven't thought about. 126SyscallReturn unimplementedFunc(SyscallDesc *desc, int num, 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. 132SyscallReturn ignoreFunc(SyscallDesc *desc, int num, ThreadContext *tc); 133 134// Target fallocateFunc() handler. 135SyscallReturn fallocateFunc(SyscallDesc *desc, int num, ThreadContext *tc); 136 137/// Target exit() handler: terminate current context. 138SyscallReturn exitFunc(SyscallDesc *desc, int num, ThreadContext *tc); 139 140/// Target exit_group() handler: terminate simulation. (exit all threads) 141SyscallReturn exitGroupFunc(SyscallDesc *desc, int num, ThreadContext *tc); 142 143/// Target set_tid_address() handler. 144SyscallReturn setTidAddressFunc(SyscallDesc *desc, int num, ThreadContext *tc); 145 146/// Target getpagesize() handler. 147SyscallReturn getpagesizeFunc(SyscallDesc *desc, int num, ThreadContext *tc); 148 149/// Target brk() handler: set brk address. 150SyscallReturn brkFunc(SyscallDesc *desc, int num, ThreadContext *tc); 151 152/// Target close() handler. 153SyscallReturn closeFunc(SyscallDesc *desc, int num, ThreadContext *tc); 154 155/// Target lseek() handler. 156SyscallReturn lseekFunc(SyscallDesc *desc, int num, ThreadContext *tc); 157 158/// Target _llseek() handler. 159SyscallReturn _llseekFunc(SyscallDesc *desc, int num, ThreadContext *tc); 160 161/// Target munmap() handler. 162SyscallReturn munmapFunc(SyscallDesc *desc, int num, ThreadContext *tc); 163 164/// Target shutdown() handler. 165SyscallReturn shutdownFunc(SyscallDesc *desc, int num, ThreadContext *tc); 166 167/// Target gethostname() handler. 168SyscallReturn gethostnameFunc(SyscallDesc *desc, int num, ThreadContext *tc); 169 170/// Target getcwd() handler. 171SyscallReturn getcwdFunc(SyscallDesc *desc, int num, ThreadContext *tc); 172 173/// Target readlink() handler. 174SyscallReturn readlinkFunc(SyscallDesc *desc, int num, ThreadContext *tc, 175 int index = 0); 176SyscallReturn readlinkFunc(SyscallDesc *desc, int num, ThreadContext *tc); 177 178/// Target unlink() handler. 179SyscallReturn unlinkHelper(SyscallDesc *desc, int num, ThreadContext *tc, 180 int index); 181SyscallReturn unlinkFunc(SyscallDesc *desc, int num, ThreadContext *tc); 182 183/// Target link() handler 184SyscallReturn linkFunc(SyscallDesc *desc, int num, ThreadContext *tc); 185 186/// Target symlink() handler. 187SyscallReturn symlinkFunc(SyscallDesc *desc, int num, ThreadContext *tc); 188 189/// Target mkdir() handler. 190SyscallReturn mkdirFunc(SyscallDesc *desc, int num, ThreadContext *tc); 191 192/// Target mknod() handler. 193SyscallReturn mknodFunc(SyscallDesc *desc, int num, ThreadContext *tc); 194 195/// Target chdir() handler. 196SyscallReturn chdirFunc(SyscallDesc *desc, int num, ThreadContext *tc); 197 198// Target rmdir() handler. 199SyscallReturn rmdirFunc(SyscallDesc *desc, int num, ThreadContext *tc); 200 201/// Target rename() handler. 202SyscallReturn renameFunc(SyscallDesc *desc, int num, ThreadContext *tc); 203 204 205/// Target truncate() handler. 206SyscallReturn truncateFunc(SyscallDesc *desc, int num, ThreadContext *tc); 207 208 209/// Target ftruncate() handler. 210SyscallReturn ftruncateFunc(SyscallDesc *desc, int num, ThreadContext *tc); 211 212 213/// Target truncate64() handler. 214SyscallReturn truncate64Func(SyscallDesc *desc, int num, ThreadContext *tc); 215 216/// Target ftruncate64() handler. 217SyscallReturn ftruncate64Func(SyscallDesc *desc, int num, ThreadContext *tc); 218 219 220/// Target umask() handler. 221SyscallReturn umaskFunc(SyscallDesc *desc, int num, ThreadContext *tc); 222 223/// Target gettid() handler. 224SyscallReturn gettidFunc(SyscallDesc *desc, int num, ThreadContext *tc); 225 226/// Target chown() handler. 227SyscallReturn chownFunc(SyscallDesc *desc, int num, ThreadContext *tc); 228 229/// Target setpgid() handler. 230SyscallReturn setpgidFunc(SyscallDesc *desc, int num, ThreadContext *tc); 231 232/// Target fchown() handler. 233SyscallReturn fchownFunc(SyscallDesc *desc, int num, ThreadContext *tc); 234 235/// Target dup() handler. 236SyscallReturn dupFunc(SyscallDesc *desc, int num, ThreadContext *tc); 237 238/// Target dup2() handler. 239SyscallReturn dup2Func(SyscallDesc *desc, int num, ThreadContext *tc); 240 241/// Target fcntl() handler. 242SyscallReturn fcntlFunc(SyscallDesc *desc, int num, ThreadContext *tc); 243 244/// Target fcntl64() handler. 245SyscallReturn fcntl64Func(SyscallDesc *desc, int num, ThreadContext *tc); 246 247/// Target setuid() handler. 248SyscallReturn setuidFunc(SyscallDesc *desc, int num, ThreadContext *tc); 249 250/// Target pipe() handler. 251SyscallReturn pipeFunc(SyscallDesc *desc, int num, ThreadContext *tc); 252 253/// Internal pipe() handler. 254SyscallReturn pipeImpl(SyscallDesc *desc, int num, ThreadContext *tc, 255 bool pseudo_pipe, bool is_pipe2=false); 256 257/// Target pipe() handler. 258SyscallReturn pipe2Func(SyscallDesc *desc, int num, ThreadContext *tc); 259 260/// Target getpid() handler. 261SyscallReturn getpidFunc(SyscallDesc *desc, int num, ThreadContext *tc); 262 263// Target getpeername() handler. 264SyscallReturn getpeernameFunc(SyscallDesc *desc, int num, ThreadContext *tc); 265 266// Target bind() handler. 267SyscallReturn bindFunc(SyscallDesc *desc, int num, ThreadContext *tc); 268 269// Target listen() handler. 270SyscallReturn listenFunc(SyscallDesc *desc, int num, ThreadContext *tc); 271 272// Target connect() handler. 273SyscallReturn connectFunc(SyscallDesc *desc, int num, ThreadContext *tc); 274 275#if defined(SYS_getdents) 276// Target getdents() handler. 277SyscallReturn getdentsFunc(SyscallDesc *desc, int num, ThreadContext *tc); 278#endif 279 280#if defined(SYS_getdents64) 281// Target getdents() handler. 282SyscallReturn getdents64Func(SyscallDesc *desc, int num, ThreadContext *tc); 283#endif 284 285// Target sendto() handler. 286SyscallReturn sendtoFunc(SyscallDesc *desc, int num, ThreadContext *tc); 287 288// Target recvfrom() handler. 289SyscallReturn recvfromFunc(SyscallDesc *desc, int num, ThreadContext *tc); 290 291// Target recvmsg() handler. 292SyscallReturn recvmsgFunc(SyscallDesc *desc, int num, ThreadContext *tc); 293 294// Target sendmsg() handler. 295SyscallReturn sendmsgFunc(SyscallDesc *desc, int num, ThreadContext *tc); 296 297// Target getuid() handler. 298SyscallReturn getuidFunc(SyscallDesc *desc, int num, ThreadContext *tc); 299 300/// Target getgid() handler. 301SyscallReturn getgidFunc(SyscallDesc *desc, int num, ThreadContext *tc); 302 303/// Target getppid() handler. 304SyscallReturn getppidFunc(SyscallDesc *desc, int num, ThreadContext *tc); 305 306/// Target geteuid() handler. 307SyscallReturn geteuidFunc(SyscallDesc *desc, int num, ThreadContext *tc); 308 309/// Target getegid() handler. 310SyscallReturn getegidFunc(SyscallDesc *desc, int num, ThreadContext *tc); 311 312/// Target access() handler 313SyscallReturn accessFunc(SyscallDesc *desc, int num, ThreadContext *tc); 314SyscallReturn accessFunc(SyscallDesc *desc, int num, ThreadContext *tc, 315 int index); 316 317// Target getsockopt() handler. 318SyscallReturn getsockoptFunc(SyscallDesc *desc, int num, ThreadContext *tc); 319 320// Target setsockopt() handler. 321SyscallReturn setsockoptFunc(SyscallDesc *desc, int num, ThreadContext *tc); 322 323// Target getsockname() handler. 324SyscallReturn getsocknameFunc(SyscallDesc *desc, int num, ThreadContext *tc); 325 326/// Futex system call 327/// Implemented by Daniel Sanchez 328/// Used by printf's in multi-threaded apps 329template <class OS> 330SyscallReturn 331futexFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 332{ 333 using namespace std; 334 335 int index = 0; 336 auto process = tc->getProcessPtr(); 337 338 Addr uaddr = process->getSyscallArg(tc, index); 339 int op = process->getSyscallArg(tc, index); 340 int val = process->getSyscallArg(tc, index); 341 int timeout M5_VAR_USED = process->getSyscallArg(tc, index); 342 Addr uaddr2 M5_VAR_USED = process->getSyscallArg(tc, index); 343 int val3 = process->getSyscallArg(tc, index); 344 345 /* 346 * Unsupported option that does not affect the correctness of the 347 * application. This is a performance optimization utilized by Linux. 348 */ 349 op &= ~OS::TGT_FUTEX_PRIVATE_FLAG; 350 op &= ~OS::TGT_FUTEX_CLOCK_REALTIME_FLAG; 351 352 FutexMap &futex_map = tc->getSystemPtr()->futexMap; 353 354 if (OS::TGT_FUTEX_WAIT == op || OS::TGT_FUTEX_WAIT_BITSET == op) { 355 // Ensure futex system call accessed atomically. 356 BufferArg buf(uaddr, sizeof(int)); 357 buf.copyIn(tc->getVirtProxy()); 358 int mem_val = *(int*)buf.bufferPtr(); 359 360 /* 361 * The value in memory at uaddr is not equal with the expected val 362 * (a different thread must have changed it before the system call was 363 * invoked). In this case, we need to throw an error. 364 */ 365 if (val != mem_val) 366 return -OS::TGT_EWOULDBLOCK; 367 368 if (OS::TGT_FUTEX_WAIT) { 369 futex_map.suspend(uaddr, process->tgid(), tc); 370 } else { 371 futex_map.suspend_bitset(uaddr, process->tgid(), tc, val3); 372 } 373 374 return 0; 375 } else if (OS::TGT_FUTEX_WAKE == op) { 376 return futex_map.wakeup(uaddr, process->tgid(), val); 377 } else if (OS::TGT_FUTEX_WAKE_BITSET == op) { 378 return futex_map.wakeup_bitset(uaddr, process->tgid(), val3); 379 } else if (OS::TGT_FUTEX_REQUEUE == op || 380 OS::TGT_FUTEX_CMP_REQUEUE == op) { 381 382 // Ensure futex system call accessed atomically. 383 BufferArg buf(uaddr, sizeof(int)); 384 buf.copyIn(tc->getVirtProxy()); 385 int mem_val = *(int*)buf.bufferPtr(); 386 /* 387 * For CMP_REQUEUE, the whole operation is only started only if 388 * val3 is still the value of the futex pointed to by uaddr. 389 */ 390 if (OS::TGT_FUTEX_CMP_REQUEUE && val3 != mem_val) 391 return -OS::TGT_EWOULDBLOCK; 392 return futex_map.requeue(uaddr, process->tgid(), val, timeout, uaddr2); 393 } else if (OS::TGT_FUTEX_WAKE_OP == op) { 394 /* 395 * The FUTEX_WAKE_OP operation is equivalent to executing the 396 * following code atomically and totally ordered with respect to 397 * other futex operations on any of the two supplied futex words: 398 * 399 * int oldval = *(int *) addr2; 400 * *(int *) addr2 = oldval op oparg; 401 * futex(addr1, FUTEX_WAKE, val, 0, 0, 0); 402 * if (oldval cmp cmparg) 403 * futex(addr2, FUTEX_WAKE, val2, 0, 0, 0); 404 * 405 * (op, oparg, cmp, cmparg are encoded in val3) 406 * 407 * +---+---+-----------+-----------+ 408 * |op |cmp| oparg | cmparg | 409 * +---+---+-----------+-----------+ 410 * 4 4 12 12 <== # of bits 411 * 412 * reference: http://man7.org/linux/man-pages/man2/futex.2.html 413 * 414 */ 415 // get value from simulated-space 416 BufferArg buf(uaddr2, sizeof(int)); 417 buf.copyIn(tc->getVirtProxy()); 418 int oldval = *(int*)buf.bufferPtr(); 419 int newval = oldval; 420 // extract op, oparg, cmp, cmparg from val3 421 int wake_cmparg = val3 & 0xfff; 422 int wake_oparg = (val3 & 0xfff000) >> 12; 423 int wake_cmp = (val3 & 0xf000000) >> 24; 424 int wake_op = (val3 & 0xf0000000) >> 28; 425 if ((wake_op & OS::TGT_FUTEX_OP_ARG_SHIFT) >> 3 == 1) 426 wake_oparg = (1 << wake_oparg); 427 wake_op &= ~OS::TGT_FUTEX_OP_ARG_SHIFT; 428 // perform operation on the value of the second futex 429 if (wake_op == OS::TGT_FUTEX_OP_SET) 430 newval = wake_oparg; 431 else if (wake_op == OS::TGT_FUTEX_OP_ADD) 432 newval += wake_oparg; 433 else if (wake_op == OS::TGT_FUTEX_OP_OR) 434 newval |= wake_oparg; 435 else if (wake_op == OS::TGT_FUTEX_OP_ANDN) 436 newval &= ~wake_oparg; 437 else if (wake_op == OS::TGT_FUTEX_OP_XOR) 438 newval ^= wake_oparg; 439 // copy updated value back to simulated-space 440 *(int*)buf.bufferPtr() = newval; 441 buf.copyOut(tc->getVirtProxy()); 442 // perform the first wake-up 443 int woken1 = futex_map.wakeup(uaddr, process->tgid(), val); 444 int woken2 = 0; 445 // calculate the condition of the second wake-up 446 bool is_wake2 = false; 447 if (wake_cmp == OS::TGT_FUTEX_OP_CMP_EQ) 448 is_wake2 = oldval == wake_cmparg; 449 else if (wake_cmp == OS::TGT_FUTEX_OP_CMP_NE) 450 is_wake2 = oldval != wake_cmparg; 451 else if (wake_cmp == OS::TGT_FUTEX_OP_CMP_LT) 452 is_wake2 = oldval < wake_cmparg; 453 else if (wake_cmp == OS::TGT_FUTEX_OP_CMP_LE) 454 is_wake2 = oldval <= wake_cmparg; 455 else if (wake_cmp == OS::TGT_FUTEX_OP_CMP_GT) 456 is_wake2 = oldval > wake_cmparg; 457 else if (wake_cmp == OS::TGT_FUTEX_OP_CMP_GE) 458 is_wake2 = oldval >= wake_cmparg; 459 // perform the second wake-up 460 if (is_wake2) 461 woken2 = futex_map.wakeup(uaddr2, process->tgid(), timeout); 462 463 return woken1 + woken2; 464 } 465 warn("futex: op %d not implemented; ignoring.", op); 466 return -ENOSYS; 467} 468 469 470/// Pseudo Funcs - These functions use a different return convension, 471/// returning a second value in a register other than the normal return register 472SyscallReturn pipePseudoFunc(SyscallDesc *desc, int num, ThreadContext *tc); 473 474/// Target getpidPseudo() handler. 475SyscallReturn getpidPseudoFunc(SyscallDesc *desc, int num, ThreadContext *tc); 476 477/// Target getuidPseudo() handler. 478SyscallReturn getuidPseudoFunc(SyscallDesc *desc, int num, ThreadContext *tc); 479 480/// Target getgidPseudo() handler. 481SyscallReturn getgidPseudoFunc(SyscallDesc *desc, int num, ThreadContext *tc); 482 483 484/// A readable name for 1,000,000, for converting microseconds to seconds. 485const int one_million = 1000000; 486/// A readable name for 1,000,000,000, for converting nanoseconds to seconds. 487const int one_billion = 1000000000; 488 489/// Approximate seconds since the epoch (1/1/1970). About a billion, 490/// by my reckoning. We want to keep this a constant (not use the 491/// real-world time) to keep simulations repeatable. 492const unsigned seconds_since_epoch = 1000000000; 493 494/// Helper function to convert current elapsed time to seconds and 495/// microseconds. 496template <class T1, class T2> 497void 498getElapsedTimeMicro(T1 &sec, T2 &usec) 499{ 500 uint64_t elapsed_usecs = curTick() / SimClock::Int::us; 501 sec = elapsed_usecs / one_million; 502 usec = elapsed_usecs % one_million; 503} 504 505/// Helper function to convert current elapsed time to seconds and 506/// nanoseconds. 507template <class T1, class T2> 508void 509getElapsedTimeNano(T1 &sec, T2 &nsec) 510{ 511 uint64_t elapsed_nsecs = curTick() / SimClock::Int::ns; 512 sec = elapsed_nsecs / one_billion; 513 nsec = elapsed_nsecs % one_billion; 514} 515 516////////////////////////////////////////////////////////////////////// 517// 518// The following emulation functions are generic, but need to be 519// templated to account for differences in types, constants, etc. 520// 521////////////////////////////////////////////////////////////////////// 522 523 typedef struct statfs hst_statfs; 524#if NO_STAT64 525 typedef struct stat hst_stat; 526 typedef struct stat hst_stat64; 527#else 528 typedef struct stat hst_stat; 529 typedef struct stat64 hst_stat64; 530#endif 531 532//// Helper function to convert a host stat buffer to a target stat 533//// buffer. Also copies the target buffer out to the simulated 534//// memory space. Used by stat(), fstat(), and lstat(). 535 536template <typename target_stat, typename host_stat> 537void 538convertStatBuf(target_stat &tgt, host_stat *host, bool fakeTTY = false) 539{ 540 using namespace TheISA; 541 542 if (fakeTTY) 543 tgt->st_dev = 0xA; 544 else 545 tgt->st_dev = host->st_dev; 546 tgt->st_dev = TheISA::htog(tgt->st_dev); 547 tgt->st_ino = host->st_ino; 548 tgt->st_ino = TheISA::htog(tgt->st_ino); 549 tgt->st_mode = host->st_mode; 550 if (fakeTTY) { 551 // Claim to be a character device 552 tgt->st_mode &= ~S_IFMT; // Clear S_IFMT 553 tgt->st_mode |= S_IFCHR; // Set S_IFCHR 554 } 555 tgt->st_mode = TheISA::htog(tgt->st_mode); 556 tgt->st_nlink = host->st_nlink; 557 tgt->st_nlink = TheISA::htog(tgt->st_nlink); 558 tgt->st_uid = host->st_uid; 559 tgt->st_uid = TheISA::htog(tgt->st_uid); 560 tgt->st_gid = host->st_gid; 561 tgt->st_gid = TheISA::htog(tgt->st_gid); 562 if (fakeTTY) 563 tgt->st_rdev = 0x880d; 564 else 565 tgt->st_rdev = host->st_rdev; 566 tgt->st_rdev = TheISA::htog(tgt->st_rdev); 567 tgt->st_size = host->st_size; 568 tgt->st_size = TheISA::htog(tgt->st_size); 569 tgt->st_atimeX = host->st_atime; 570 tgt->st_atimeX = TheISA::htog(tgt->st_atimeX); 571 tgt->st_mtimeX = host->st_mtime; 572 tgt->st_mtimeX = TheISA::htog(tgt->st_mtimeX); 573 tgt->st_ctimeX = host->st_ctime; 574 tgt->st_ctimeX = TheISA::htog(tgt->st_ctimeX); 575 // Force the block size to be 8KB. This helps to ensure buffered io works 576 // consistently across different hosts. 577 tgt->st_blksize = 0x2000; 578 tgt->st_blksize = TheISA::htog(tgt->st_blksize); 579 tgt->st_blocks = host->st_blocks; 580 tgt->st_blocks = TheISA::htog(tgt->st_blocks); 581} 582 583// Same for stat64 584 585template <typename target_stat, typename host_stat64> 586void 587convertStat64Buf(target_stat &tgt, host_stat64 *host, bool fakeTTY = false) 588{ 589 using namespace TheISA; 590 591 convertStatBuf<target_stat, host_stat64>(tgt, host, fakeTTY); 592#if defined(STAT_HAVE_NSEC) 593 tgt->st_atime_nsec = host->st_atime_nsec; 594 tgt->st_atime_nsec = TheISA::htog(tgt->st_atime_nsec); 595 tgt->st_mtime_nsec = host->st_mtime_nsec; 596 tgt->st_mtime_nsec = TheISA::htog(tgt->st_mtime_nsec); 597 tgt->st_ctime_nsec = host->st_ctime_nsec; 598 tgt->st_ctime_nsec = TheISA::htog(tgt->st_ctime_nsec); 599#else 600 tgt->st_atime_nsec = 0; 601 tgt->st_mtime_nsec = 0; 602 tgt->st_ctime_nsec = 0; 603#endif 604} 605 606// Here are a couple of convenience functions 607template<class OS> 608void 609copyOutStatBuf(PortProxy &mem, Addr addr, 610 hst_stat *host, bool fakeTTY = false) 611{ 612 typedef TypedBufferArg<typename OS::tgt_stat> tgt_stat_buf; 613 tgt_stat_buf tgt(addr); 614 convertStatBuf<tgt_stat_buf, hst_stat>(tgt, host, fakeTTY); 615 tgt.copyOut(mem); 616} 617 618template<class OS> 619void 620copyOutStat64Buf(PortProxy &mem, Addr addr, 621 hst_stat64 *host, bool fakeTTY = false) 622{ 623 typedef TypedBufferArg<typename OS::tgt_stat64> tgt_stat_buf; 624 tgt_stat_buf tgt(addr); 625 convertStat64Buf<tgt_stat_buf, hst_stat64>(tgt, host, fakeTTY); 626 tgt.copyOut(mem); 627} 628 629template <class OS> 630void 631copyOutStatfsBuf(PortProxy &mem, Addr addr, 632 hst_statfs *host) 633{ 634 TypedBufferArg<typename OS::tgt_statfs> tgt(addr); 635 636 tgt->f_type = TheISA::htog(host->f_type); 637#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) 638 tgt->f_bsize = TheISA::htog(host->f_iosize); 639#else 640 tgt->f_bsize = TheISA::htog(host->f_bsize); 641#endif 642 tgt->f_blocks = TheISA::htog(host->f_blocks); 643 tgt->f_bfree = TheISA::htog(host->f_bfree); 644 tgt->f_bavail = TheISA::htog(host->f_bavail); 645 tgt->f_files = TheISA::htog(host->f_files); 646 tgt->f_ffree = TheISA::htog(host->f_ffree); 647 memcpy(&tgt->f_fsid, &host->f_fsid, sizeof(host->f_fsid)); 648#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) 649 tgt->f_namelen = TheISA::htog(host->f_namemax); 650 tgt->f_frsize = TheISA::htog(host->f_bsize); 651#elif defined(__APPLE__) 652 tgt->f_namelen = 0; 653 tgt->f_frsize = 0; 654#else 655 tgt->f_namelen = TheISA::htog(host->f_namelen); 656 tgt->f_frsize = TheISA::htog(host->f_frsize); 657#endif 658#if defined(__linux__) 659 memcpy(&tgt->f_spare, &host->f_spare, sizeof(host->f_spare)); 660#else 661 /* 662 * The fields are different sizes per OS. Don't bother with 663 * f_spare or f_reserved on non-Linux for now. 664 */ 665 memset(&tgt->f_spare, 0, sizeof(tgt->f_spare)); 666#endif 667 668 tgt.copyOut(mem); 669} 670 671/// Target ioctl() handler. For the most part, programs call ioctl() 672/// only to find out if their stdout is a tty, to determine whether to 673/// do line or block buffering. We always claim that output fds are 674/// not TTYs to provide repeatable results. 675template <class OS> 676SyscallReturn 677ioctlFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 678{ 679 int index = 0; 680 auto p = tc->getProcessPtr(); 681 682 int tgt_fd = p->getSyscallArg(tc, index); 683 unsigned req = p->getSyscallArg(tc, index); 684 685 DPRINTF_SYSCALL(Verbose, "ioctl(%d, 0x%x, ...)\n", tgt_fd, req); 686 687 if (OS::isTtyReq(req)) 688 return -ENOTTY; 689 690 auto dfdp = std::dynamic_pointer_cast<DeviceFDEntry>((*p->fds)[tgt_fd]); 691 if (dfdp) { 692 EmulatedDriver *emul_driver = dfdp->getDriver(); 693 if (emul_driver) 694 return emul_driver->ioctl(tc, req); 695 } 696 697 auto sfdp = std::dynamic_pointer_cast<SocketFDEntry>((*p->fds)[tgt_fd]); 698 if (sfdp) { 699 int status; 700 701 switch (req) { 702 case SIOCGIFCONF: { 703 Addr conf_addr = p->getSyscallArg(tc, index); 704 BufferArg conf_arg(conf_addr, sizeof(ifconf)); 705 conf_arg.copyIn(tc->getVirtProxy()); 706 707 ifconf *conf = (ifconf*)conf_arg.bufferPtr(); 708 Addr ifc_buf_addr = (Addr)conf->ifc_buf; 709 BufferArg ifc_buf_arg(ifc_buf_addr, conf->ifc_len); 710 ifc_buf_arg.copyIn(tc->getVirtProxy()); 711 712 conf->ifc_buf = (char*)ifc_buf_arg.bufferPtr(); 713 714 status = ioctl(sfdp->getSimFD(), req, conf_arg.bufferPtr()); 715 if (status != -1) { 716 conf->ifc_buf = (char*)ifc_buf_addr; 717 ifc_buf_arg.copyOut(tc->getVirtProxy()); 718 conf_arg.copyOut(tc->getVirtProxy()); 719 } 720 721 return status; 722 } 723 case SIOCGIFFLAGS: 724#if defined(__linux__) 725 case SIOCGIFINDEX: 726#endif 727 case SIOCGIFNETMASK: 728 case SIOCGIFADDR: 729#if defined(__linux__) 730 case SIOCGIFHWADDR: 731#endif 732 case SIOCGIFMTU: { 733 Addr req_addr = p->getSyscallArg(tc, index); 734 BufferArg req_arg(req_addr, sizeof(ifreq)); 735 req_arg.copyIn(tc->getVirtProxy()); 736 737 status = ioctl(sfdp->getSimFD(), req, req_arg.bufferPtr()); 738 if (status != -1) 739 req_arg.copyOut(tc->getVirtProxy()); 740 return status; 741 } 742 } 743 } 744 745 /** 746 * For lack of a better return code, return ENOTTY. Ideally, we should 747 * return something better here, but at least we issue the warning. 748 */ 749 warn("Unsupported ioctl call (return ENOTTY): ioctl(%d, 0x%x, ...) @ \n", 750 tgt_fd, req, tc->pcState()); 751 return -ENOTTY; 752} 753 754template <class OS> 755SyscallReturn 756openImpl(SyscallDesc *desc, int callnum, ThreadContext *tc, bool isopenat) 757{ 758 int index = 0; 759 auto p = tc->getProcessPtr(); 760 int tgt_dirfd = -1; 761 762 /** 763 * If using the openat variant, read in the target directory file 764 * descriptor from the simulated process. 765 */ 766 if (isopenat) 767 tgt_dirfd = p->getSyscallArg(tc, index); 768 769 /** 770 * Retrieve the simulated process' memory proxy and then read in the path 771 * string from that memory space into the host's working memory space. 772 */ 773 std::string path; 774 if (!tc->getVirtProxy().tryReadString(path, p->getSyscallArg(tc, index))) 775 return -EFAULT; 776 777#ifdef __CYGWIN32__ 778 int host_flags = O_BINARY; 779#else 780 int host_flags = 0; 781#endif 782 /** 783 * Translate target flags into host flags. Flags exist which are not 784 * ported between architectures which can cause check failures. 785 */ 786 int tgt_flags = p->getSyscallArg(tc, index); 787 for (int i = 0; i < OS::NUM_OPEN_FLAGS; i++) { 788 if (tgt_flags & OS::openFlagTable[i].tgtFlag) { 789 tgt_flags &= ~OS::openFlagTable[i].tgtFlag; 790 host_flags |= OS::openFlagTable[i].hostFlag; 791 } 792 } 793 if (tgt_flags) { 794 warn("open%s: cannot decode flags 0x%x", 795 isopenat ? "at" : "", tgt_flags); 796 } 797#ifdef __CYGWIN32__ 798 host_flags |= O_BINARY; 799#endif 800 801 int mode = p->getSyscallArg(tc, index); 802 803 /** 804 * If the simulated process called open or openat with AT_FDCWD specified, 805 * take the current working directory value which was passed into the 806 * process class as a Python parameter and append the current path to 807 * create a full path. 808 * Otherwise, openat with a valid target directory file descriptor has 809 * been called. If the path option, which was passed in as a parameter, 810 * is not absolute, retrieve the directory file descriptor's path and 811 * prepend it to the path passed in as a parameter. 812 * In every case, we should have a full path (which is relevant to the 813 * host) to work with after this block has been passed. 814 */ 815 std::string redir_path = path; 816 std::string abs_path = path; 817 if (!isopenat || tgt_dirfd == OS::TGT_AT_FDCWD) { 818 abs_path = p->absolutePath(path, true); 819 redir_path = p->checkPathRedirect(path); 820 } else if (!startswith(path, "/")) { 821 std::shared_ptr<FDEntry> fdep = ((*p->fds)[tgt_dirfd]); 822 auto ffdp = std::dynamic_pointer_cast<FileFDEntry>(fdep); 823 if (!ffdp) 824 return -EBADF; 825 abs_path = ffdp->getFileName() + path; 826 redir_path = p->checkPathRedirect(abs_path); 827 } 828 829 /** 830 * Since this is an emulated environment, we create pseudo file 831 * descriptors for device requests that have been registered with 832 * the process class through Python; this allows us to create a file 833 * descriptor for subsequent ioctl or mmap calls. 834 */ 835 if (startswith(abs_path, "/dev/")) { 836 std::string filename = abs_path.substr(strlen("/dev/")); 837 EmulatedDriver *drv = p->findDriver(filename); 838 if (drv) { 839 DPRINTF_SYSCALL(Verbose, "open%s: passing call to " 840 "driver open with path[%s]\n", 841 isopenat ? "at" : "", abs_path.c_str()); 842 return drv->open(tc, mode, host_flags); 843 } 844 /** 845 * Fall through here for pass through to host devices, such 846 * as /dev/zero 847 */ 848 } 849 850 /** 851 * We make several attempts resolve a call to open. 852 * 853 * 1) Resolve any path redirection before hand. This will set the path 854 * up with variable 'redir_path' which may contain a modified path or 855 * the original path value. This should already be done in prior code. 856 * 2) Try to handle the access using 'special_paths'. Some special_paths 857 * and files cannot be called on the host and need to be handled as 858 * special cases inside the simulator. These special_paths are handled by 859 * C++ routines to provide output back to userspace. 860 * 3) If the full path that was created above does not match any of the 861 * special cases, pass it through to the open call on the __HOST__ to let 862 * the host open the file on our behalf. Again, the openImpl tries to 863 * USE_THE_HOST_FILESYSTEM_OPEN (with a possible redirection to the 864 * faux-filesystem files). The faux-filesystem is dynamically created 865 * during simulator configuration using Python functions. 866 * 4) If the host cannot open the file, the open attempt failed in "3)". 867 * Return the host's error code back through the system call to the 868 * simulated process. If running a debug trace, also notify the user that 869 * the open call failed. 870 * 871 * Any success will set sim_fd to something other than -1 and skip the 872 * next conditions effectively bypassing them. 873 */ 874 int sim_fd = -1; 875 std::string used_path; 876 std::vector<std::string> special_paths = 877 { "/proc/meminfo/", "/system/", "/platform/", "/etc/passwd" }; 878 for (auto entry : special_paths) { 879 if (startswith(path, entry)) { 880 sim_fd = OS::openSpecialFile(abs_path, p, tc); 881 used_path = abs_path; 882 } 883 } 884 if (sim_fd == -1) { 885 sim_fd = open(redir_path.c_str(), host_flags, mode); 886 used_path = redir_path; 887 } 888 if (sim_fd == -1) { 889 int local = -errno; 890 DPRINTF_SYSCALL(Verbose, "open%s: failed -> path:%s " 891 "(inferred from:%s)\n", isopenat ? "at" : "", 892 used_path.c_str(), path.c_str()); 893 return local; 894 } 895 896 /** 897 * The file was opened successfully and needs to be recorded in the 898 * process' file descriptor array so that it can be retrieved later. 899 * The target file descriptor that is chosen will be the lowest unused 900 * file descriptor. 901 * Return the indirect target file descriptor back to the simulated 902 * process to act as a handle for the opened file. 903 */ 904 auto ffdp = std::make_shared<FileFDEntry>(sim_fd, host_flags, path, 0); 905 int tgt_fd = p->fds->allocFD(ffdp); 906 DPRINTF_SYSCALL(Verbose, "open%s: sim_fd[%d], target_fd[%d] -> path:%s\n" 907 "(inferred from:%s)\n", isopenat ? "at" : "", 908 sim_fd, tgt_fd, used_path.c_str(), path.c_str()); 909 return tgt_fd; 910} 911 912/// Target open() handler. 913template <class OS> 914SyscallReturn 915openFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 916{ 917 return openImpl<OS>(desc, callnum, tc, false); 918} 919 920/// Target openat() handler. 921template <class OS> 922SyscallReturn 923openatFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 924{ 925 return openImpl<OS>(desc, callnum, tc, true); 926} 927 928/// Target unlinkat() handler. 929template <class OS> 930SyscallReturn 931unlinkatFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 932{ 933 int index = 0; 934 auto process = tc->getProcessPtr(); 935 int dirfd = process->getSyscallArg(tc, index); 936 if (dirfd != OS::TGT_AT_FDCWD) 937 warn("unlinkat: first argument not AT_FDCWD; unlikely to work"); 938 939 return unlinkHelper(desc, callnum, tc, 1); 940} 941 942/// Target facessat() handler 943template <class OS> 944SyscallReturn 945faccessatFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 946{ 947 int index = 0; 948 auto process = tc->getProcessPtr(); 949 int dirfd = process->getSyscallArg(tc, index); 950 if (dirfd != OS::TGT_AT_FDCWD) 951 warn("faccessat: first argument not AT_FDCWD; unlikely to work"); 952 return accessFunc(desc, callnum, tc, 1); 953} 954 955/// Target readlinkat() handler 956template <class OS> 957SyscallReturn 958readlinkatFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 959{ 960 int index = 0; 961 auto process = tc->getProcessPtr(); 962 int dirfd = process->getSyscallArg(tc, index); 963 if (dirfd != OS::TGT_AT_FDCWD) 964 warn("openat: first argument not AT_FDCWD; unlikely to work"); 965 return readlinkFunc(desc, callnum, tc, 1); 966} 967 968/// Target renameat() handler. 969template <class OS> 970SyscallReturn 971renameatFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 972{ 973 int index = 0; 974 auto process = tc->getProcessPtr(); 975 976 int olddirfd = process->getSyscallArg(tc, index); 977 if (olddirfd != OS::TGT_AT_FDCWD) 978 warn("renameat: first argument not AT_FDCWD; unlikely to work"); 979 980 std::string old_name; 981 982 if (!tc->getVirtProxy().tryReadString(old_name, 983 process->getSyscallArg(tc, index))) 984 return -EFAULT; 985 986 int newdirfd = process->getSyscallArg(tc, index); 987 if (newdirfd != OS::TGT_AT_FDCWD) 988 warn("renameat: third argument not AT_FDCWD; unlikely to work"); 989 990 std::string new_name; 991 992 if (!tc->getVirtProxy().tryReadString(new_name, 993 process->getSyscallArg(tc, index))) 994 return -EFAULT; 995 996 // Adjust path for cwd and redirection 997 old_name = process->checkPathRedirect(old_name); 998 new_name = process->checkPathRedirect(new_name); 999 1000 int result = rename(old_name.c_str(), new_name.c_str()); 1001 return (result == -1) ? -errno : result; 1002} 1003 1004/// Target sysinfo() handler. 1005template <class OS> 1006SyscallReturn 1007sysinfoFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 1008{ 1009 int index = 0; 1010 auto process = tc->getProcessPtr(); 1011 1012 TypedBufferArg<typename OS::tgt_sysinfo> 1013 sysinfo(process->getSyscallArg(tc, index)); 1014 1015 sysinfo->uptime = seconds_since_epoch; 1016 sysinfo->totalram = process->system->memSize(); 1017 sysinfo->mem_unit = 1; 1018 1019 sysinfo.copyOut(tc->getVirtProxy()); 1020 1021 return 0; 1022} 1023 1024/// Target chmod() handler. 1025template <class OS> 1026SyscallReturn 1027chmodFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 1028{ 1029 std::string path; 1030 auto process = tc->getProcessPtr(); 1031 1032 int index = 0; 1033 if (!tc->getVirtProxy().tryReadString(path, 1034 process->getSyscallArg(tc, index))) { 1035 return -EFAULT; 1036 } 1037 1038 uint32_t mode = process->getSyscallArg(tc, index); 1039 mode_t hostMode = 0; 1040 1041 // XXX translate mode flags via OS::something??? 1042 hostMode = mode; 1043 1044 // Adjust path for cwd and redirection 1045 path = process->checkPathRedirect(path); 1046 1047 // do the chmod 1048 int result = chmod(path.c_str(), hostMode); 1049 if (result < 0) 1050 return -errno; 1051 1052 return 0; 1053} 1054 1055template <class OS> 1056SyscallReturn 1057pollFunc(SyscallDesc *desc, int num, ThreadContext *tc) 1058{ 1059 int index = 0; 1060 auto p = tc->getProcessPtr(); 1061 Addr fdsPtr = p->getSyscallArg(tc, index); 1062 int nfds = p->getSyscallArg(tc, index); 1063 int tmout = p->getSyscallArg(tc, index); 1064 1065 BufferArg fdsBuf(fdsPtr, sizeof(struct pollfd) * nfds); 1066 fdsBuf.copyIn(tc->getVirtProxy()); 1067 1068 /** 1069 * Record the target file descriptors in a local variable. We need to 1070 * replace them with host file descriptors but we need a temporary copy 1071 * for later. Afterwards, replace each target file descriptor in the 1072 * poll_fd array with its host_fd. 1073 */ 1074 int temp_tgt_fds[nfds]; 1075 for (index = 0; index < nfds; index++) { 1076 temp_tgt_fds[index] = ((struct pollfd *)fdsBuf.bufferPtr())[index].fd; 1077 auto tgt_fd = temp_tgt_fds[index]; 1078 auto hbfdp = std::dynamic_pointer_cast<HBFDEntry>((*p->fds)[tgt_fd]); 1079 if (!hbfdp) 1080 return -EBADF; 1081 auto host_fd = hbfdp->getSimFD(); 1082 ((struct pollfd *)fdsBuf.bufferPtr())[index].fd = host_fd; 1083 } 1084 1085 /** 1086 * We cannot allow an infinite poll to occur or it will inevitably cause 1087 * a deadlock in the gem5 simulator with clone. We must pass in tmout with 1088 * a non-negative value, however it also makes no sense to poll on the 1089 * underlying host for any other time than tmout a zero timeout. 1090 */ 1091 int status; 1092 if (tmout < 0) { 1093 status = poll((struct pollfd *)fdsBuf.bufferPtr(), nfds, 0); 1094 if (status == 0) { 1095 /** 1096 * If blocking indefinitely, check the signal list to see if a 1097 * signal would break the poll out of the retry cycle and try 1098 * to return the signal interrupt instead. 1099 */ 1100 System *sysh = tc->getSystemPtr(); 1101 std::list<BasicSignal>::iterator it; 1102 for (it=sysh->signalList.begin(); it!=sysh->signalList.end(); it++) 1103 if (it->receiver == p) 1104 return -EINTR; 1105 return SyscallReturn::retry(); 1106 } 1107 } else 1108 status = poll((struct pollfd *)fdsBuf.bufferPtr(), nfds, 0); 1109 1110 if (status == -1) 1111 return -errno; 1112 1113 /** 1114 * Replace each host_fd in the returned poll_fd array with its original 1115 * target file descriptor. 1116 */ 1117 for (index = 0; index < nfds; index++) { 1118 auto tgt_fd = temp_tgt_fds[index]; 1119 ((struct pollfd *)fdsBuf.bufferPtr())[index].fd = tgt_fd; 1120 } 1121 1122 /** 1123 * Copy out the pollfd struct because the host may have updated fields 1124 * in the structure. 1125 */ 1126 fdsBuf.copyOut(tc->getVirtProxy()); 1127 1128 return status; 1129} 1130 1131/// Target fchmod() handler. 1132template <class OS> 1133SyscallReturn 1134fchmodFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 1135{ 1136 int index = 0; 1137 auto p = tc->getProcessPtr(); 1138 int tgt_fd = p->getSyscallArg(tc, index); 1139 uint32_t mode = p->getSyscallArg(tc, index); 1140 1141 auto ffdp = std::dynamic_pointer_cast<FileFDEntry>((*p->fds)[tgt_fd]); 1142 if (!ffdp) 1143 return -EBADF; 1144 int sim_fd = ffdp->getSimFD(); 1145 1146 mode_t hostMode = mode; 1147 1148 int result = fchmod(sim_fd, hostMode); 1149 1150 return (result < 0) ? -errno : 0; 1151} 1152 1153/// Target mremap() handler. 1154template <class OS> 1155SyscallReturn 1156mremapFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 1157{ 1158 int index = 0; 1159 auto process = tc->getProcessPtr(); 1160 Addr start = process->getSyscallArg(tc, index); 1161 uint64_t old_length = process->getSyscallArg(tc, index); 1162 uint64_t new_length = process->getSyscallArg(tc, index); 1163 uint64_t flags = process->getSyscallArg(tc, index); 1164 uint64_t provided_address = 0; 1165 bool use_provided_address = flags & OS::TGT_MREMAP_FIXED; 1166 1167 if (use_provided_address) 1168 provided_address = process->getSyscallArg(tc, index); 1169 1170 if ((start % TheISA::PageBytes != 0) || 1171 (provided_address % TheISA::PageBytes != 0)) { 1172 warn("mremap failing: arguments not page aligned"); 1173 return -EINVAL; 1174 } 1175 1176 new_length = roundUp(new_length, TheISA::PageBytes); 1177 1178 if (new_length > old_length) { 1179 std::shared_ptr<MemState> mem_state = process->memState; 1180 Addr mmap_end = mem_state->getMmapEnd(); 1181 1182 if ((start + old_length) == mmap_end && 1183 (!use_provided_address || provided_address == start)) { 1184 // This case cannot occur when growing downward, as 1185 // start is greater than or equal to mmap_end. 1186 uint64_t diff = new_length - old_length; 1187 process->allocateMem(mmap_end, diff); 1188 mem_state->setMmapEnd(mmap_end + diff); 1189 return start; 1190 } else { 1191 if (!use_provided_address && !(flags & OS::TGT_MREMAP_MAYMOVE)) { 1192 warn("can't remap here and MREMAP_MAYMOVE flag not set\n"); 1193 return -ENOMEM; 1194 } else { 1195 uint64_t new_start = provided_address; 1196 if (!use_provided_address) { 1197 new_start = process->mmapGrowsDown() ? 1198 mmap_end - new_length : mmap_end; 1199 mmap_end = process->mmapGrowsDown() ? 1200 new_start : mmap_end + new_length; 1201 mem_state->setMmapEnd(mmap_end); 1202 } 1203 1204 process->pTable->remap(start, old_length, new_start); 1205 warn("mremapping to new vaddr %08p-%08p, adding %d\n", 1206 new_start, new_start + new_length, 1207 new_length - old_length); 1208 // add on the remaining unallocated pages 1209 process->allocateMem(new_start + old_length, 1210 new_length - old_length, 1211 use_provided_address /* clobber */); 1212 if (use_provided_address && 1213 ((new_start + new_length > mem_state->getMmapEnd() && 1214 !process->mmapGrowsDown()) || 1215 (new_start < mem_state->getMmapEnd() && 1216 process->mmapGrowsDown()))) { 1217 // something fishy going on here, at least notify the user 1218 // @todo: increase mmap_end? 1219 warn("mmap region limit exceeded with MREMAP_FIXED\n"); 1220 } 1221 warn("returning %08p as start\n", new_start); 1222 return new_start; 1223 } 1224 } 1225 } else { 1226 if (use_provided_address && provided_address != start) 1227 process->pTable->remap(start, new_length, provided_address); 1228 process->pTable->unmap(start + new_length, old_length - new_length); 1229 return use_provided_address ? provided_address : start; 1230 } 1231} 1232 1233/// Target stat() handler. 1234template <class OS> 1235SyscallReturn 1236statFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 1237{ 1238 std::string path; 1239 auto process = tc->getProcessPtr(); 1240 1241 int index = 0; 1242 if (!tc->getVirtProxy().tryReadString(path, 1243 process->getSyscallArg(tc, index))) { 1244 return -EFAULT; 1245 } 1246 Addr bufPtr = process->getSyscallArg(tc, index); 1247 1248 // Adjust path for cwd and redirection 1249 path = process->checkPathRedirect(path); 1250 1251 struct stat hostBuf; 1252 int result = stat(path.c_str(), &hostBuf); 1253 1254 if (result < 0) 1255 return -errno; 1256 1257 copyOutStatBuf<OS>(tc->getVirtProxy(), bufPtr, &hostBuf); 1258 1259 return 0; 1260} 1261 1262 1263/// Target stat64() handler. 1264template <class OS> 1265SyscallReturn 1266stat64Func(SyscallDesc *desc, int callnum, ThreadContext *tc) 1267{ 1268 std::string path; 1269 auto process = tc->getProcessPtr(); 1270 1271 int index = 0; 1272 if (!tc->getVirtProxy().tryReadString(path, 1273 process->getSyscallArg(tc, index))) 1274 return -EFAULT; 1275 Addr bufPtr = process->getSyscallArg(tc, index); 1276 1277 // Adjust path for cwd and redirection 1278 path = process->checkPathRedirect(path); 1279 1280#if NO_STAT64 1281 struct stat hostBuf; 1282 int result = stat(path.c_str(), &hostBuf); 1283#else 1284 struct stat64 hostBuf; 1285 int result = stat64(path.c_str(), &hostBuf); 1286#endif 1287 1288 if (result < 0) 1289 return -errno; 1290 1291 copyOutStat64Buf<OS>(tc->getVirtProxy(), bufPtr, &hostBuf); 1292 1293 return 0; 1294} 1295 1296 1297/// Target fstatat64() handler. 1298template <class OS> 1299SyscallReturn 1300fstatat64Func(SyscallDesc *desc, int callnum, ThreadContext *tc) 1301{ 1302 int index = 0; 1303 auto process = tc->getProcessPtr(); 1304 int dirfd = process->getSyscallArg(tc, index); 1305 if (dirfd != OS::TGT_AT_FDCWD) 1306 warn("fstatat64: first argument not AT_FDCWD; unlikely to work"); 1307 1308 std::string path; 1309 if (!tc->getVirtProxy().tryReadString(path, 1310 process->getSyscallArg(tc, index))) 1311 return -EFAULT; 1312 Addr bufPtr = process->getSyscallArg(tc, index); 1313 1314 // Adjust path for cwd and redirection 1315 path = process->checkPathRedirect(path); 1316 1317#if NO_STAT64 1318 struct stat hostBuf; 1319 int result = stat(path.c_str(), &hostBuf); 1320#else 1321 struct stat64 hostBuf; 1322 int result = stat64(path.c_str(), &hostBuf); 1323#endif 1324 1325 if (result < 0) 1326 return -errno; 1327 1328 copyOutStat64Buf<OS>(tc->getVirtProxy(), bufPtr, &hostBuf); 1329 1330 return 0; 1331} 1332 1333 1334/// Target fstat64() handler. 1335template <class OS> 1336SyscallReturn 1337fstat64Func(SyscallDesc *desc, int callnum, ThreadContext *tc) 1338{ 1339 int index = 0; 1340 auto p = tc->getProcessPtr(); 1341 int tgt_fd = p->getSyscallArg(tc, index); 1342 Addr bufPtr = p->getSyscallArg(tc, index); 1343 1344 auto ffdp = std::dynamic_pointer_cast<HBFDEntry>((*p->fds)[tgt_fd]); 1345 if (!ffdp) 1346 return -EBADF; 1347 int sim_fd = ffdp->getSimFD(); 1348 1349#if NO_STAT64 1350 struct stat hostBuf; 1351 int result = fstat(sim_fd, &hostBuf); 1352#else 1353 struct stat64 hostBuf; 1354 int result = fstat64(sim_fd, &hostBuf); 1355#endif 1356 1357 if (result < 0) 1358 return -errno; 1359 1360 copyOutStat64Buf<OS>(tc->getVirtProxy(), bufPtr, &hostBuf, (sim_fd == 1)); 1361 1362 return 0; 1363} 1364 1365 1366/// Target lstat() handler. 1367template <class OS> 1368SyscallReturn 1369lstatFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 1370{ 1371 std::string path; 1372 auto process = tc->getProcessPtr(); 1373 1374 int index = 0; 1375 if (!tc->getVirtProxy().tryReadString(path, 1376 process->getSyscallArg(tc, index))) { 1377 return -EFAULT; 1378 } 1379 Addr bufPtr = process->getSyscallArg(tc, index); 1380 1381 // Adjust path for cwd and redirection 1382 path = process->checkPathRedirect(path); 1383 1384 struct stat hostBuf; 1385 int result = lstat(path.c_str(), &hostBuf); 1386 1387 if (result < 0) 1388 return -errno; 1389 1390 copyOutStatBuf<OS>(tc->getVirtProxy(), bufPtr, &hostBuf); 1391 1392 return 0; 1393} 1394 1395/// Target lstat64() handler. 1396template <class OS> 1397SyscallReturn 1398lstat64Func(SyscallDesc *desc, int callnum, ThreadContext *tc) 1399{ 1400 std::string path; 1401 auto process = tc->getProcessPtr(); 1402 1403 int index = 0; 1404 if (!tc->getVirtProxy().tryReadString(path, 1405 process->getSyscallArg(tc, index))) { 1406 return -EFAULT; 1407 } 1408 Addr bufPtr = process->getSyscallArg(tc, index); 1409 1410 // Adjust path for cwd and redirection 1411 path = process->checkPathRedirect(path); 1412 1413#if NO_STAT64 1414 struct stat hostBuf; 1415 int result = lstat(path.c_str(), &hostBuf); 1416#else 1417 struct stat64 hostBuf; 1418 int result = lstat64(path.c_str(), &hostBuf); 1419#endif 1420 1421 if (result < 0) 1422 return -errno; 1423 1424 copyOutStat64Buf<OS>(tc->getVirtProxy(), bufPtr, &hostBuf); 1425 1426 return 0; 1427} 1428 1429/// Target fstat() handler. 1430template <class OS> 1431SyscallReturn 1432fstatFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 1433{ 1434 int index = 0; 1435 auto p = tc->getProcessPtr(); 1436 int tgt_fd = p->getSyscallArg(tc, index); 1437 Addr bufPtr = p->getSyscallArg(tc, index); 1438 1439 DPRINTF_SYSCALL(Verbose, "fstat(%d, ...)\n", tgt_fd); 1440 1441 auto ffdp = std::dynamic_pointer_cast<FileFDEntry>((*p->fds)[tgt_fd]); 1442 if (!ffdp) 1443 return -EBADF; 1444 int sim_fd = ffdp->getSimFD(); 1445 1446 struct stat hostBuf; 1447 int result = fstat(sim_fd, &hostBuf); 1448 1449 if (result < 0) 1450 return -errno; 1451 1452 copyOutStatBuf<OS>(tc->getVirtProxy(), bufPtr, &hostBuf, (sim_fd == 1)); 1453 1454 return 0; 1455} 1456 1457/// Target statfs() handler. 1458template <class OS> 1459SyscallReturn 1460statfsFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 1461{ 1462#if defined(__linux__) 1463 std::string path; 1464 auto process = tc->getProcessPtr(); 1465 1466 int index = 0; 1467 if (!tc->getVirtProxy().tryReadString(path, 1468 process->getSyscallArg(tc, index))) { 1469 return -EFAULT; 1470 } 1471 Addr bufPtr = process->getSyscallArg(tc, index); 1472 1473 // Adjust path for cwd and redirection 1474 path = process->checkPathRedirect(path); 1475 1476 struct statfs hostBuf; 1477 int result = statfs(path.c_str(), &hostBuf); 1478 1479 if (result < 0) 1480 return -errno; 1481 1482 copyOutStatfsBuf<OS>(tc->getVirtProxy(), bufPtr, &hostBuf); 1483 return 0; 1484#else 1485 warnUnsupportedOS("statfs"); 1486 return -1; 1487#endif 1488} 1489 1490template <class OS> 1491SyscallReturn 1492cloneFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 1493{ 1494 int index = 0; 1495 1496 auto p = tc->getProcessPtr(); 1497 RegVal flags = p->getSyscallArg(tc, index); 1498 RegVal newStack = p->getSyscallArg(tc, index); 1499 Addr ptidPtr = p->getSyscallArg(tc, index); 1500 1501#if THE_ISA == RISCV_ISA or THE_ISA == ARM_ISA 1502 /** 1503 * Linux sets CLONE_BACKWARDS flag for RISC-V and Arm. 1504 * The flag defines the list of clone() arguments in the following 1505 * order: flags -> newStack -> ptidPtr -> tlsPtr -> ctidPtr 1506 */ 1507 Addr tlsPtr = p->getSyscallArg(tc, index); 1508 Addr ctidPtr = p->getSyscallArg(tc, index); 1509#else 1510 Addr ctidPtr = p->getSyscallArg(tc, index); 1511 Addr tlsPtr = p->getSyscallArg(tc, index); 1512#endif 1513 1514 if (((flags & OS::TGT_CLONE_SIGHAND)&& !(flags & OS::TGT_CLONE_VM)) || 1515 ((flags & OS::TGT_CLONE_THREAD) && !(flags & OS::TGT_CLONE_SIGHAND)) || 1516 ((flags & OS::TGT_CLONE_FS) && (flags & OS::TGT_CLONE_NEWNS)) || 1517 ((flags & OS::TGT_CLONE_NEWIPC) && (flags & OS::TGT_CLONE_SYSVSEM)) || 1518 ((flags & OS::TGT_CLONE_NEWPID) && (flags & OS::TGT_CLONE_THREAD)) || 1519 ((flags & OS::TGT_CLONE_VM) && !(newStack))) 1520 return -EINVAL; 1521 1522 ThreadContext *ctc; 1523 if (!(ctc = p->findFreeContext())) { 1524 DPRINTF_SYSCALL(Verbose, "clone: no spare thread context in system" 1525 "[cpu %d, thread %d]", tc->cpuId(), tc->threadId()); 1526 return -EAGAIN; 1527 } 1528 1529 /** 1530 * Note that ProcessParams is generated by swig and there are no other 1531 * examples of how to create anything but this default constructor. The 1532 * fields are manually initialized instead of passing parameters to the 1533 * constructor. 1534 */ 1535 ProcessParams *pp = new ProcessParams(); 1536 pp->executable.assign(*(new std::string(p->progName()))); 1537 pp->cmd.push_back(*(new std::string(p->progName()))); 1538 pp->system = p->system; 1539 pp->cwd.assign(p->tgtCwd); 1540 pp->input.assign("stdin"); 1541 pp->output.assign("stdout"); 1542 pp->errout.assign("stderr"); 1543 pp->uid = p->uid(); 1544 pp->euid = p->euid(); 1545 pp->gid = p->gid(); 1546 pp->egid = p->egid(); 1547 1548 /* Find the first free PID that's less than the maximum */ 1549 std::set<int> const& pids = p->system->PIDs; 1550 int temp_pid = *pids.begin(); 1551 do { 1552 temp_pid++; 1553 } while (pids.find(temp_pid) != pids.end()); 1554 if (temp_pid >= System::maxPID) 1555 fatal("temp_pid is too large: %d", temp_pid); 1556 1557 pp->pid = temp_pid; 1558 pp->ppid = (flags & OS::TGT_CLONE_THREAD) ? p->ppid() : p->pid(); 1559 pp->useArchPT = p->useArchPT; 1560 pp->kvmInSE = p->kvmInSE; 1561 Process *cp = pp->create(); 1562 delete pp; 1563 1564 Process *owner = ctc->getProcessPtr(); 1565 ctc->setProcessPtr(cp); 1566 cp->assignThreadContext(ctc->contextId()); 1567 owner->revokeThreadContext(ctc->contextId()); 1568 1569 if (flags & OS::TGT_CLONE_PARENT_SETTID) { 1570 BufferArg ptidBuf(ptidPtr, sizeof(long)); 1571 long *ptid = (long *)ptidBuf.bufferPtr(); 1572 *ptid = cp->pid(); 1573 ptidBuf.copyOut(tc->getVirtProxy()); 1574 } 1575 1576 if (flags & OS::TGT_CLONE_THREAD) { 1577 cp->pTable->shared = true; 1578 cp->useForClone = true; 1579 } 1580 cp->initState(); 1581 p->clone(tc, ctc, cp, flags); 1582 1583 if (flags & OS::TGT_CLONE_THREAD) { 1584 delete cp->sigchld; 1585 cp->sigchld = p->sigchld; 1586 } else if (flags & OS::TGT_SIGCHLD) { 1587 *cp->sigchld = true; 1588 } 1589 1590 if (flags & OS::TGT_CLONE_CHILD_SETTID) { 1591 BufferArg ctidBuf(ctidPtr, sizeof(long)); 1592 long *ctid = (long *)ctidBuf.bufferPtr(); 1593 *ctid = cp->pid(); 1594 ctidBuf.copyOut(ctc->getVirtProxy()); 1595 } 1596 1597 if (flags & OS::TGT_CLONE_CHILD_CLEARTID) 1598 cp->childClearTID = (uint64_t)ctidPtr; 1599 1600 ctc->clearArchRegs(); 1601 1602 OS::archClone(flags, p, cp, tc, ctc, newStack, tlsPtr); 1603 1604 cp->setSyscallReturn(ctc, 0); 1605 1606#if THE_ISA == ALPHA_ISA 1607 ctc->setIntReg(TheISA::SyscallSuccessReg, 0); 1608#elif THE_ISA == SPARC_ISA 1609 tc->setIntReg(TheISA::SyscallPseudoReturnReg, 0); 1610 ctc->setIntReg(TheISA::SyscallPseudoReturnReg, 1); 1611#endif 1612 1613 if (p->kvmInSE) { 1614#if THE_ISA == X86_ISA 1615 ctc->pcState(tc->readIntReg(TheISA::INTREG_RCX)); 1616#else 1617 panic("KVM CPU model is not supported for this ISA"); 1618#endif 1619 } else { 1620 TheISA::PCState cpc = tc->pcState(); 1621 cpc.advance(); 1622 ctc->pcState(cpc); 1623 } 1624 ctc->activate(); 1625 1626 return cp->pid(); 1627} 1628 1629/// Target fstatfs() handler. 1630template <class OS> 1631SyscallReturn 1632fstatfsFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 1633{ 1634 int index = 0; 1635 auto p = tc->getProcessPtr(); 1636 int tgt_fd = p->getSyscallArg(tc, index); 1637 Addr bufPtr = p->getSyscallArg(tc, index); 1638 1639 auto ffdp = std::dynamic_pointer_cast<FileFDEntry>((*p->fds)[tgt_fd]); 1640 if (!ffdp) 1641 return -EBADF; 1642 int sim_fd = ffdp->getSimFD(); 1643 1644 struct statfs hostBuf; 1645 int result = fstatfs(sim_fd, &hostBuf); 1646 1647 if (result < 0) 1648 return -errno; 1649 1650 copyOutStatfsBuf<OS>(tc->getVirtProxy(), bufPtr, &hostBuf); 1651 1652 return 0; 1653} 1654 1655/// Target readv() handler. 1656template <class OS> 1657SyscallReturn 1658readvFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 1659{ 1660 int index = 0; 1661 auto p = tc->getProcessPtr(); 1662 int tgt_fd = p->getSyscallArg(tc, index); 1663 1664 auto ffdp = std::dynamic_pointer_cast<FileFDEntry>((*p->fds)[tgt_fd]); 1665 if (!ffdp) 1666 return -EBADF; 1667 int sim_fd = ffdp->getSimFD(); 1668 1669 PortProxy &prox = tc->getVirtProxy(); 1670 uint64_t tiov_base = p->getSyscallArg(tc, index); 1671 size_t count = p->getSyscallArg(tc, index); 1672 typename OS::tgt_iovec tiov[count]; 1673 struct iovec hiov[count]; 1674 for (size_t i = 0; i < count; ++i) { 1675 prox.readBlob(tiov_base + (i * sizeof(typename OS::tgt_iovec)), 1676 &tiov[i], sizeof(typename OS::tgt_iovec)); 1677 hiov[i].iov_len = TheISA::gtoh(tiov[i].iov_len); 1678 hiov[i].iov_base = new char [hiov[i].iov_len]; 1679 } 1680 1681 int result = readv(sim_fd, hiov, count); 1682 int local_errno = errno; 1683 1684 for (size_t i = 0; i < count; ++i) { 1685 if (result != -1) { 1686 prox.writeBlob(TheISA::htog(tiov[i].iov_base), 1687 hiov[i].iov_base, hiov[i].iov_len); 1688 } 1689 delete [] (char *)hiov[i].iov_base; 1690 } 1691 1692 return (result == -1) ? -local_errno : result; 1693} 1694 1695/// Target writev() handler. 1696template <class OS> 1697SyscallReturn 1698writevFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 1699{ 1700 int index = 0; 1701 auto p = tc->getProcessPtr(); 1702 int tgt_fd = p->getSyscallArg(tc, index); 1703 1704 auto hbfdp = std::dynamic_pointer_cast<HBFDEntry>((*p->fds)[tgt_fd]); 1705 if (!hbfdp) 1706 return -EBADF; 1707 int sim_fd = hbfdp->getSimFD(); 1708 1709 PortProxy &prox = tc->getVirtProxy(); 1710 uint64_t tiov_base = p->getSyscallArg(tc, index); 1711 size_t count = p->getSyscallArg(tc, index); 1712 struct iovec hiov[count]; 1713 for (size_t i = 0; i < count; ++i) { 1714 typename OS::tgt_iovec tiov; 1715 1716 prox.readBlob(tiov_base + i*sizeof(typename OS::tgt_iovec), 1717 &tiov, sizeof(typename OS::tgt_iovec)); 1718 hiov[i].iov_len = TheISA::gtoh(tiov.iov_len); 1719 hiov[i].iov_base = new char [hiov[i].iov_len]; 1720 prox.readBlob(TheISA::gtoh(tiov.iov_base), hiov[i].iov_base, 1721 hiov[i].iov_len); 1722 } 1723 1724 int result = writev(sim_fd, hiov, count); 1725 1726 for (size_t i = 0; i < count; ++i) 1727 delete [] (char *)hiov[i].iov_base; 1728 1729 return (result == -1) ? -errno : result; 1730} 1731 1732/// Real mmap handler. 1733template <class OS> 1734SyscallReturn 1735mmapImpl(SyscallDesc *desc, int num, ThreadContext *tc, bool is_mmap2) 1736{ 1737 int index = 0; 1738 auto p = tc->getProcessPtr(); 1739 Addr start = p->getSyscallArg(tc, index); 1740 uint64_t length = p->getSyscallArg(tc, index); 1741 int prot = p->getSyscallArg(tc, index); 1742 int tgt_flags = p->getSyscallArg(tc, index); 1743 int tgt_fd = p->getSyscallArg(tc, index); 1744 int offset = p->getSyscallArg(tc, index); 1745 1746 if (is_mmap2) 1747 offset *= TheISA::PageBytes; 1748 1749 if (start & (TheISA::PageBytes - 1) || 1750 offset & (TheISA::PageBytes - 1) || 1751 (tgt_flags & OS::TGT_MAP_PRIVATE && 1752 tgt_flags & OS::TGT_MAP_SHARED) || 1753 (!(tgt_flags & OS::TGT_MAP_PRIVATE) && 1754 !(tgt_flags & OS::TGT_MAP_SHARED)) || 1755 !length) { 1756 return -EINVAL; 1757 } 1758 1759 if ((prot & PROT_WRITE) && (tgt_flags & OS::TGT_MAP_SHARED)) { 1760 // With shared mmaps, there are two cases to consider: 1761 // 1) anonymous: writes should modify the mapping and this should be 1762 // visible to observers who share the mapping. Currently, it's 1763 // difficult to update the shared mapping because there's no 1764 // structure which maintains information about the which virtual 1765 // memory areas are shared. If that structure existed, it would be 1766 // possible to make the translations point to the same frames. 1767 // 2) file-backed: writes should modify the mapping and the file 1768 // which is backed by the mapping. The shared mapping problem is the 1769 // same as what was mentioned about the anonymous mappings. For 1770 // file-backed mappings, the writes to the file are difficult 1771 // because it requires syncing what the mapping holds with the file 1772 // that resides on the host system. So, any write on a real system 1773 // would cause the change to be propagated to the file mapping at 1774 // some point in the future (the inode is tracked along with the 1775 // mapping). This isn't guaranteed to always happen, but it usually 1776 // works well enough. The guarantee is provided by the msync system 1777 // call. We could force the change through with shared mappings with 1778 // a call to msync, but that again would require more information 1779 // than we currently maintain. 1780 warn("mmap: writing to shared mmap region is currently " 1781 "unsupported. The write succeeds on the target, but it " 1782 "will not be propagated to the host or shared mappings"); 1783 } 1784 1785 length = roundUp(length, TheISA::PageBytes); 1786 1787 int sim_fd = -1; 1788 uint8_t *pmap = nullptr; 1789 if (!(tgt_flags & OS::TGT_MAP_ANONYMOUS)) { 1790 std::shared_ptr<FDEntry> fdep = (*p->fds)[tgt_fd]; 1791 1792 auto dfdp = std::dynamic_pointer_cast<DeviceFDEntry>(fdep); 1793 if (dfdp) { 1794 EmulatedDriver *emul_driver = dfdp->getDriver(); 1795 return emul_driver->mmap(tc, start, length, prot, tgt_flags, 1796 tgt_fd, offset); 1797 } 1798 1799 auto ffdp = std::dynamic_pointer_cast<FileFDEntry>(fdep); 1800 if (!ffdp) 1801 return -EBADF; 1802 sim_fd = ffdp->getSimFD(); 1803 1804 pmap = (decltype(pmap))mmap(nullptr, length, PROT_READ, MAP_PRIVATE, 1805 sim_fd, offset); 1806 1807 if (pmap == (decltype(pmap))-1) { 1808 warn("mmap: failed to map file into host address space"); 1809 return -errno; 1810 } 1811 } 1812 1813 // Extend global mmap region if necessary. Note that we ignore the 1814 // start address unless MAP_FIXED is specified. 1815 if (!(tgt_flags & OS::TGT_MAP_FIXED)) { 1816 std::shared_ptr<MemState> mem_state = p->memState; 1817 Addr mmap_end = mem_state->getMmapEnd(); 1818 1819 start = p->mmapGrowsDown() ? mmap_end - length : mmap_end; 1820 mmap_end = p->mmapGrowsDown() ? start : mmap_end + length; 1821 1822 mem_state->setMmapEnd(mmap_end); 1823 } 1824 1825 DPRINTF_SYSCALL(Verbose, " mmap range is 0x%x - 0x%x\n", 1826 start, start + length - 1); 1827 1828 // We only allow mappings to overwrite existing mappings if 1829 // TGT_MAP_FIXED is set. Otherwise it shouldn't be a problem 1830 // because we ignore the start hint if TGT_MAP_FIXED is not set. 1831 int clobber = tgt_flags & OS::TGT_MAP_FIXED; 1832 if (clobber) { 1833 for (auto tc : p->system->threadContexts) { 1834 // If we might be overwriting old mappings, we need to 1835 // invalidate potentially stale mappings out of the TLBs. 1836 tc->getDTBPtr()->flushAll(); 1837 tc->getITBPtr()->flushAll(); 1838 } 1839 } 1840 1841 // Allocate physical memory and map it in. If the page table is already 1842 // mapped and clobber is not set, the simulator will issue throw a 1843 // fatal and bail out of the simulation. 1844 p->allocateMem(start, length, clobber); 1845 1846 // Transfer content into target address space. 1847 PortProxy &tp = tc->getVirtProxy(); 1848 if (tgt_flags & OS::TGT_MAP_ANONYMOUS) { 1849 // In general, we should zero the mapped area for anonymous mappings, 1850 // with something like: 1851 // tp.memsetBlob(start, 0, length); 1852 // However, given that we don't support sparse mappings, and 1853 // some applications can map a couple of gigabytes of space 1854 // (intending sparse usage), that can get painfully expensive. 1855 // Fortunately, since we don't properly implement munmap either, 1856 // there's no danger of remapping used memory, so for now all 1857 // newly mapped memory should already be zeroed so we can skip it. 1858 } else { 1859 // It is possible to mmap an area larger than a file, however 1860 // accessing unmapped portions the system triggers a "Bus error" 1861 // on the host. We must know when to stop copying the file from 1862 // the host into the target address space. 1863 struct stat file_stat; 1864 if (fstat(sim_fd, &file_stat) > 0) 1865 fatal("mmap: cannot stat file"); 1866 1867 // Copy the portion of the file that is resident. This requires 1868 // checking both the mmap size and the filesize that we are 1869 // trying to mmap into this space; the mmap size also depends 1870 // on the specified offset into the file. 1871 uint64_t size = std::min((uint64_t)file_stat.st_size - offset, 1872 length); 1873 tp.writeBlob(start, pmap, size); 1874 1875 // Cleanup the mmap region before exiting this function. 1876 munmap(pmap, length); 1877 1878 // Maintain the symbol table for dynamic executables. 1879 // The loader will call mmap to map the images into its address 1880 // space and we intercept that here. We can verify that we are 1881 // executing inside the loader by checking the program counter value. 1882 // XXX: with multiprogrammed workloads or multi-node configurations, 1883 // this will not work since there is a single global symbol table. 1884 ObjectFile *interpreter = p->getInterpreter(); 1885 if (interpreter) { 1886 Addr text_start = interpreter->textBase(); 1887 Addr text_end = text_start + interpreter->textSize(); 1888 1889 Addr pc = tc->pcState().pc(); 1890 1891 if (pc >= text_start && pc < text_end) { 1892 std::shared_ptr<FDEntry> fdep = (*p->fds)[tgt_fd]; 1893 auto ffdp = std::dynamic_pointer_cast<FileFDEntry>(fdep); 1894 ObjectFile *lib = createObjectFile(ffdp->getFileName()); 1895 1896 if (lib) { 1897 lib->loadAllSymbols(debugSymbolTable, 1898 lib->textBase(), start); 1899 } 1900 } 1901 } 1902 1903 // Note that we do not zero out the remainder of the mapping. This 1904 // is done by a real system, but it probably will not affect 1905 // execution (hopefully). 1906 } 1907 1908 return start; 1909} 1910 1911template <class OS> 1912SyscallReturn 1913pwrite64Func(SyscallDesc *desc, int num, ThreadContext *tc) 1914{ 1915 int index = 0; 1916 auto p = tc->getProcessPtr(); 1917 int tgt_fd = p->getSyscallArg(tc, index); 1918 Addr bufPtr = p->getSyscallArg(tc, index); 1919 int nbytes = p->getSyscallArg(tc, index); 1920 int offset = p->getSyscallArg(tc, index); 1921 1922 auto ffdp = std::dynamic_pointer_cast<FileFDEntry>((*p->fds)[tgt_fd]); 1923 if (!ffdp) 1924 return -EBADF; 1925 int sim_fd = ffdp->getSimFD(); 1926 1927 BufferArg bufArg(bufPtr, nbytes); 1928 bufArg.copyIn(tc->getVirtProxy()); 1929 1930 int bytes_written = pwrite(sim_fd, bufArg.bufferPtr(), nbytes, offset); 1931 1932 return (bytes_written == -1) ? -errno : bytes_written; 1933} 1934 1935/// Target mmap() handler. 1936template <class OS> 1937SyscallReturn 1938mmapFunc(SyscallDesc *desc, int num, ThreadContext *tc) 1939{ 1940 return mmapImpl<OS>(desc, num, tc, false); 1941} 1942 1943/// Target mmap2() handler. 1944template <class OS> 1945SyscallReturn 1946mmap2Func(SyscallDesc *desc, int num, ThreadContext *tc) 1947{ 1948 return mmapImpl<OS>(desc, num, tc, true); 1949} 1950 1951/// Target getrlimit() handler. 1952template <class OS> 1953SyscallReturn 1954getrlimitFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 1955{ 1956 int index = 0; 1957 auto process = tc->getProcessPtr(); 1958 unsigned resource = process->getSyscallArg(tc, index); 1959 TypedBufferArg<typename OS::rlimit> rlp(process->getSyscallArg(tc, index)); 1960 1961 switch (resource) { 1962 case OS::TGT_RLIMIT_STACK: 1963 // max stack size in bytes: make up a number (8MB for now) 1964 rlp->rlim_cur = rlp->rlim_max = 8 * 1024 * 1024; 1965 rlp->rlim_cur = TheISA::htog(rlp->rlim_cur); 1966 rlp->rlim_max = TheISA::htog(rlp->rlim_max); 1967 break; 1968 1969 case OS::TGT_RLIMIT_DATA: 1970 // max data segment size in bytes: make up a number 1971 rlp->rlim_cur = rlp->rlim_max = 256 * 1024 * 1024; 1972 rlp->rlim_cur = TheISA::htog(rlp->rlim_cur); 1973 rlp->rlim_max = TheISA::htog(rlp->rlim_max); 1974 break; 1975 1976 case OS::TGT_RLIMIT_NPROC: 1977 rlp->rlim_cur = rlp->rlim_max = tc->getSystemPtr()->numContexts(); 1978 rlp->rlim_cur = TheISA::htog(rlp->rlim_cur); 1979 rlp->rlim_max = TheISA::htog(rlp->rlim_max); 1980 break; 1981 1982 default: 1983 warn("getrlimit: unimplemented resource %d", resource); 1984 return -EINVAL; 1985 break; 1986 } 1987 1988 rlp.copyOut(tc->getVirtProxy()); 1989 return 0; 1990} 1991 1992template <class OS> 1993SyscallReturn 1994prlimitFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 1995{ 1996 int index = 0; 1997 auto process = tc->getProcessPtr(); 1998 if (process->getSyscallArg(tc, index) != 0) 1999 { 2000 warn("prlimit: ignoring rlimits for nonzero pid"); 2001 return -EPERM; 2002 } 2003 int resource = process->getSyscallArg(tc, index); 2004 Addr n = process->getSyscallArg(tc, index); 2005 if (n != 0) 2006 warn("prlimit: ignoring new rlimit"); 2007 Addr o = process->getSyscallArg(tc, index); 2008 if (o != 0) 2009 { 2010 TypedBufferArg<typename OS::rlimit> rlp(o); 2011 switch (resource) { 2012 case OS::TGT_RLIMIT_STACK: 2013 // max stack size in bytes: make up a number (8MB for now) 2014 rlp->rlim_cur = rlp->rlim_max = 8 * 1024 * 1024; 2015 rlp->rlim_cur = TheISA::htog(rlp->rlim_cur); 2016 rlp->rlim_max = TheISA::htog(rlp->rlim_max); 2017 break; 2018 case OS::TGT_RLIMIT_DATA: 2019 // max data segment size in bytes: make up a number 2020 rlp->rlim_cur = rlp->rlim_max = 256*1024*1024; 2021 rlp->rlim_cur = TheISA::htog(rlp->rlim_cur); 2022 rlp->rlim_max = TheISA::htog(rlp->rlim_max); 2023 break; 2024 default: 2025 warn("prlimit: unimplemented resource %d", resource); 2026 return -EINVAL; 2027 break; 2028 } 2029 rlp.copyOut(tc->getVirtProxy()); 2030 } 2031 return 0; 2032} 2033 2034/// Target clock_gettime() function. 2035template <class OS> 2036SyscallReturn 2037clock_gettimeFunc(SyscallDesc *desc, int num, ThreadContext *tc) 2038{ 2039 int index = 1; 2040 auto p = tc->getProcessPtr(); 2041 //int clk_id = p->getSyscallArg(tc, index); 2042 TypedBufferArg<typename OS::timespec> tp(p->getSyscallArg(tc, index)); 2043 2044 getElapsedTimeNano(tp->tv_sec, tp->tv_nsec); 2045 tp->tv_sec += seconds_since_epoch; 2046 tp->tv_sec = TheISA::htog(tp->tv_sec); 2047 tp->tv_nsec = TheISA::htog(tp->tv_nsec); 2048 2049 tp.copyOut(tc->getVirtProxy()); 2050 2051 return 0; 2052} 2053 2054/// Target clock_getres() function. 2055template <class OS> 2056SyscallReturn 2057clock_getresFunc(SyscallDesc *desc, int num, ThreadContext *tc) 2058{ 2059 int index = 1; 2060 auto p = tc->getProcessPtr(); 2061 TypedBufferArg<typename OS::timespec> tp(p->getSyscallArg(tc, index)); 2062 2063 // Set resolution at ns, which is what clock_gettime() returns 2064 tp->tv_sec = 0; 2065 tp->tv_nsec = 1; 2066 2067 tp.copyOut(tc->getVirtProxy()); 2068 2069 return 0; 2070} 2071 2072/// Target gettimeofday() handler. 2073template <class OS> 2074SyscallReturn 2075gettimeofdayFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 2076{ 2077 int index = 0; 2078 auto process = tc->getProcessPtr(); 2079 TypedBufferArg<typename OS::timeval> tp(process->getSyscallArg(tc, index)); 2080 2081 getElapsedTimeMicro(tp->tv_sec, tp->tv_usec); 2082 tp->tv_sec += seconds_since_epoch; 2083 tp->tv_sec = TheISA::htog(tp->tv_sec); 2084 tp->tv_usec = TheISA::htog(tp->tv_usec); 2085 2086 tp.copyOut(tc->getVirtProxy()); 2087 2088 return 0; 2089} 2090 2091 2092/// Target utimes() handler. 2093template <class OS> 2094SyscallReturn 2095utimesFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 2096{ 2097 std::string path; 2098 auto process = tc->getProcessPtr(); 2099 2100 int index = 0; 2101 if (!tc->getVirtProxy().tryReadString(path, 2102 process->getSyscallArg(tc, index))) { 2103 return -EFAULT; 2104 } 2105 2106 TypedBufferArg<typename OS::timeval [2]> 2107 tp(process->getSyscallArg(tc, index)); 2108 tp.copyIn(tc->getVirtProxy()); 2109 2110 struct timeval hostTimeval[2]; 2111 for (int i = 0; i < 2; ++i) { 2112 hostTimeval[i].tv_sec = TheISA::gtoh((*tp)[i].tv_sec); 2113 hostTimeval[i].tv_usec = TheISA::gtoh((*tp)[i].tv_usec); 2114 } 2115 2116 // Adjust path for cwd and redirection 2117 path = process->checkPathRedirect(path); 2118 2119 int result = utimes(path.c_str(), hostTimeval); 2120 2121 if (result < 0) 2122 return -errno; 2123 2124 return 0; 2125} 2126 2127template <class OS> 2128SyscallReturn 2129execveFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 2130{ 2131 desc->setFlags(0); 2132 auto p = tc->getProcessPtr(); 2133 2134 int index = 0; 2135 std::string path; 2136 PortProxy & mem_proxy = tc->getVirtProxy(); 2137 if (!mem_proxy.tryReadString(path, p->getSyscallArg(tc, index))) 2138 return -EFAULT; 2139 2140 if (access(path.c_str(), F_OK) == -1) 2141 return -EACCES; 2142 2143 auto read_in = [](std::vector<std::string> &vect, 2144 PortProxy &mem_proxy, Addr mem_loc) 2145 { 2146 for (int inc = 0; ; inc++) { 2147 BufferArg b((mem_loc + sizeof(Addr) * inc), sizeof(Addr)); 2148 b.copyIn(mem_proxy); 2149 2150 if (!*(Addr*)b.bufferPtr()) 2151 break; 2152 2153 vect.push_back(std::string()); 2154 mem_proxy.tryReadString(vect[inc], *(Addr*)b.bufferPtr()); 2155 } 2156 }; 2157 2158 /** 2159 * Note that ProcessParams is generated by swig and there are no other 2160 * examples of how to create anything but this default constructor. The 2161 * fields are manually initialized instead of passing parameters to the 2162 * constructor. 2163 */ 2164 ProcessParams *pp = new ProcessParams(); 2165 pp->executable = path; 2166 Addr argv_mem_loc = p->getSyscallArg(tc, index); 2167 read_in(pp->cmd, mem_proxy, argv_mem_loc); 2168 Addr envp_mem_loc = p->getSyscallArg(tc, index); 2169 read_in(pp->env, mem_proxy, envp_mem_loc); 2170 pp->uid = p->uid(); 2171 pp->egid = p->egid(); 2172 pp->euid = p->euid(); 2173 pp->gid = p->gid(); 2174 pp->ppid = p->ppid(); 2175 pp->pid = p->pid(); 2176 pp->input.assign("cin"); 2177 pp->output.assign("cout"); 2178 pp->errout.assign("cerr"); 2179 pp->cwd.assign(p->tgtCwd); 2180 pp->system = p->system; 2181 /** 2182 * Prevent process object creation with identical PIDs (which will trip 2183 * a fatal check in Process constructor). The execve call is supposed to 2184 * take over the currently executing process' identity but replace 2185 * whatever it is doing with a new process image. Instead of hijacking 2186 * the process object in the simulator, we create a new process object 2187 * and bind to the previous process' thread below (hijacking the thread). 2188 */ 2189 p->system->PIDs.erase(p->pid()); 2190 Process *new_p = pp->create(); 2191 delete pp; 2192 2193 /** 2194 * Work through the file descriptor array and close any files marked 2195 * close-on-exec. 2196 */ 2197 new_p->fds = p->fds; 2198 for (int i = 0; i < new_p->fds->getSize(); i++) { 2199 std::shared_ptr<FDEntry> fdep = (*new_p->fds)[i]; 2200 if (fdep && fdep->getCOE()) 2201 new_p->fds->closeFDEntry(i); 2202 } 2203 2204 *new_p->sigchld = true; 2205 2206 delete p; 2207 tc->clearArchRegs(); 2208 tc->setProcessPtr(new_p); 2209 new_p->assignThreadContext(tc->contextId()); 2210 new_p->initState(); 2211 tc->activate(); 2212 TheISA::PCState pcState = tc->pcState(); 2213 tc->setNPC(pcState.instAddr()); 2214 2215 desc->setFlags(SyscallDesc::SuppressReturnValue); 2216 return 0; 2217} 2218 2219/// Target getrusage() function. 2220template <class OS> 2221SyscallReturn 2222getrusageFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 2223{ 2224 int index = 0; 2225 auto process = tc->getProcessPtr(); 2226 int who = process->getSyscallArg(tc, index); // THREAD, SELF, or CHILDREN 2227 TypedBufferArg<typename OS::rusage> rup(process->getSyscallArg(tc, index)); 2228 2229 rup->ru_utime.tv_sec = 0; 2230 rup->ru_utime.tv_usec = 0; 2231 rup->ru_stime.tv_sec = 0; 2232 rup->ru_stime.tv_usec = 0; 2233 rup->ru_maxrss = 0; 2234 rup->ru_ixrss = 0; 2235 rup->ru_idrss = 0; 2236 rup->ru_isrss = 0; 2237 rup->ru_minflt = 0; 2238 rup->ru_majflt = 0; 2239 rup->ru_nswap = 0; 2240 rup->ru_inblock = 0; 2241 rup->ru_oublock = 0; 2242 rup->ru_msgsnd = 0; 2243 rup->ru_msgrcv = 0; 2244 rup->ru_nsignals = 0; 2245 rup->ru_nvcsw = 0; 2246 rup->ru_nivcsw = 0; 2247 2248 switch (who) { 2249 case OS::TGT_RUSAGE_SELF: 2250 getElapsedTimeMicro(rup->ru_utime.tv_sec, rup->ru_utime.tv_usec); 2251 rup->ru_utime.tv_sec = TheISA::htog(rup->ru_utime.tv_sec); 2252 rup->ru_utime.tv_usec = TheISA::htog(rup->ru_utime.tv_usec); 2253 break; 2254 2255 case OS::TGT_RUSAGE_CHILDREN: 2256 // do nothing. We have no child processes, so they take no time. 2257 break; 2258 2259 default: 2260 // don't really handle THREAD or CHILDREN, but just warn and 2261 // plow ahead 2262 warn("getrusage() only supports RUSAGE_SELF. Parameter %d ignored.", 2263 who); 2264 } 2265 2266 rup.copyOut(tc->getVirtProxy()); 2267 2268 return 0; 2269} 2270 2271/// Target times() function. 2272template <class OS> 2273SyscallReturn 2274timesFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 2275{ 2276 int index = 0; 2277 auto process = tc->getProcessPtr(); 2278 TypedBufferArg<typename OS::tms> bufp(process->getSyscallArg(tc, index)); 2279 2280 // Fill in the time structure (in clocks) 2281 int64_t clocks = curTick() * OS::M5_SC_CLK_TCK / SimClock::Int::s; 2282 bufp->tms_utime = clocks; 2283 bufp->tms_stime = 0; 2284 bufp->tms_cutime = 0; 2285 bufp->tms_cstime = 0; 2286 2287 // Convert to host endianness 2288 bufp->tms_utime = TheISA::htog(bufp->tms_utime); 2289 2290 // Write back 2291 bufp.copyOut(tc->getVirtProxy()); 2292 2293 // Return clock ticks since system boot 2294 return clocks; 2295} 2296 2297/// Target time() function. 2298template <class OS> 2299SyscallReturn 2300timeFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 2301{ 2302 typename OS::time_t sec, usec; 2303 getElapsedTimeMicro(sec, usec); 2304 sec += seconds_since_epoch; 2305 2306 int index = 0; 2307 auto process = tc->getProcessPtr(); 2308 Addr taddr = (Addr)process->getSyscallArg(tc, index); 2309 if (taddr != 0) { 2310 typename OS::time_t t = sec; 2311 t = TheISA::htog(t); 2312 PortProxy &p = tc->getVirtProxy(); 2313 p.writeBlob(taddr, &t, (int)sizeof(typename OS::time_t)); 2314 } 2315 return sec; 2316} 2317 2318template <class OS> 2319SyscallReturn 2320tgkillFunc(SyscallDesc *desc, int num, ThreadContext *tc) 2321{ 2322 int index = 0; 2323 auto process = tc->getProcessPtr(); 2324 int tgid = process->getSyscallArg(tc, index); 2325 int tid = process->getSyscallArg(tc, index); 2326 int sig = process->getSyscallArg(tc, index); 2327 2328 /** 2329 * This system call is intended to allow killing a specific thread 2330 * within an arbitrary thread group if sanctioned with permission checks. 2331 * It's usually true that threads share the termination signal as pointed 2332 * out by the pthread_kill man page and this seems to be the intended 2333 * usage. Due to this being an emulated environment, assume the following: 2334 * Threads are allowed to call tgkill because the EUID for all threads 2335 * should be the same. There is no signal handling mechanism for kernel 2336 * registration of signal handlers since signals are poorly supported in 2337 * emulation mode. Since signal handlers cannot be registered, all 2338 * threads within in a thread group must share the termination signal. 2339 * We never exhaust PIDs so there's no chance of finding the wrong one 2340 * due to PID rollover. 2341 */ 2342 2343 System *sys = tc->getSystemPtr(); 2344 Process *tgt_proc = nullptr; 2345 for (int i = 0; i < sys->numContexts(); i++) { 2346 Process *temp = sys->threadContexts[i]->getProcessPtr(); 2347 if (temp->pid() == tid) { 2348 tgt_proc = temp; 2349 break; 2350 } 2351 } 2352 2353 if (sig != 0 || sig != OS::TGT_SIGABRT) 2354 return -EINVAL; 2355 2356 if (tgt_proc == nullptr) 2357 return -ESRCH; 2358 2359 if (tgid != -1 && tgt_proc->tgid() != tgid) 2360 return -ESRCH; 2361 2362 if (sig == OS::TGT_SIGABRT) 2363 exitGroupFunc(desc, 252, tc); 2364 2365 return 0; 2366} 2367 2368template <class OS> 2369SyscallReturn 2370socketFunc(SyscallDesc *desc, int num, ThreadContext *tc) 2371{ 2372 int index = 0; 2373 auto p = tc->getProcessPtr(); 2374 int domain = p->getSyscallArg(tc, index); 2375 int type = p->getSyscallArg(tc, index); 2376 int prot = p->getSyscallArg(tc, index); 2377 2378 int sim_fd = socket(domain, type, prot); 2379 if (sim_fd == -1) 2380 return -errno; 2381 2382 auto sfdp = std::make_shared<SocketFDEntry>(sim_fd, domain, type, prot); 2383 int tgt_fd = p->fds->allocFD(sfdp); 2384 2385 return tgt_fd; 2386} 2387 2388template <class OS> 2389SyscallReturn 2390socketpairFunc(SyscallDesc *desc, int num, ThreadContext *tc) 2391{ 2392 int index = 0; 2393 auto p = tc->getProcessPtr(); 2394 int domain = p->getSyscallArg(tc, index); 2395 int type = p->getSyscallArg(tc, index); 2396 int prot = p->getSyscallArg(tc, index); 2397 Addr svPtr = p->getSyscallArg(tc, index); 2398 2399 BufferArg svBuf((Addr)svPtr, 2 * sizeof(int)); 2400 int status = socketpair(domain, type, prot, (int *)svBuf.bufferPtr()); 2401 if (status == -1) 2402 return -errno; 2403 2404 int *fds = (int *)svBuf.bufferPtr(); 2405 2406 auto sfdp1 = std::make_shared<SocketFDEntry>(fds[0], domain, type, prot); 2407 fds[0] = p->fds->allocFD(sfdp1); 2408 auto sfdp2 = std::make_shared<SocketFDEntry>(fds[1], domain, type, prot); 2409 fds[1] = p->fds->allocFD(sfdp2); 2410 svBuf.copyOut(tc->getVirtProxy()); 2411 2412 return status; 2413} 2414 2415template <class OS> 2416SyscallReturn 2417selectFunc(SyscallDesc *desc, int callnum, ThreadContext *tc) 2418{ 2419 int retval; 2420 2421 int index = 0; 2422 auto p = tc->getProcessPtr(); 2423 int nfds_t = p->getSyscallArg(tc, index); 2424 Addr fds_read_ptr = p->getSyscallArg(tc, index); 2425 Addr fds_writ_ptr = p->getSyscallArg(tc, index); 2426 Addr fds_excp_ptr = p->getSyscallArg(tc, index); 2427 Addr time_val_ptr = p->getSyscallArg(tc, index); 2428 2429 TypedBufferArg<typename OS::fd_set> rd_t(fds_read_ptr); 2430 TypedBufferArg<typename OS::fd_set> wr_t(fds_writ_ptr); 2431 TypedBufferArg<typename OS::fd_set> ex_t(fds_excp_ptr); 2432 TypedBufferArg<typename OS::timeval> tp(time_val_ptr); 2433 2434 /** 2435 * Host fields. Notice that these use the definitions from the system 2436 * headers instead of the gem5 headers and libraries. If the host and 2437 * target have different header file definitions, this will not work. 2438 */ 2439 fd_set rd_h; 2440 FD_ZERO(&rd_h); 2441 fd_set wr_h; 2442 FD_ZERO(&wr_h); 2443 fd_set ex_h; 2444 FD_ZERO(&ex_h); 2445 2446 /** 2447 * Copy in the fd_set from the target. 2448 */ 2449 if (fds_read_ptr) 2450 rd_t.copyIn(tc->getVirtProxy()); 2451 if (fds_writ_ptr) 2452 wr_t.copyIn(tc->getVirtProxy()); 2453 if (fds_excp_ptr) 2454 ex_t.copyIn(tc->getVirtProxy()); 2455 2456 /** 2457 * We need to translate the target file descriptor set into a host file 2458 * descriptor set. This involves both our internal process fd array 2459 * and the fd_set defined in Linux header files. The nfds field also 2460 * needs to be updated as it will be only target specific after 2461 * retrieving it from the target; the nfds value is expected to be the 2462 * highest file descriptor that needs to be checked, so we need to extend 2463 * it out for nfds_h when we do the update. 2464 */ 2465 int nfds_h = 0; 2466 std::map<int, int> trans_map; 2467 auto try_add_host_set = [&](fd_set *tgt_set_entry, 2468 fd_set *hst_set_entry, 2469 int iter) -> bool 2470 { 2471 /** 2472 * By this point, we know that we are looking at a valid file 2473 * descriptor set on the target. We need to check if the target file 2474 * descriptor value passed in as iter is part of the set. 2475 */ 2476 if (FD_ISSET(iter, tgt_set_entry)) { 2477 /** 2478 * We know that the target file descriptor belongs to the set, 2479 * but we do not yet know if the file descriptor is valid or 2480 * that we have a host mapping. Check that now. 2481 */ 2482 auto hbfdp = std::dynamic_pointer_cast<HBFDEntry>((*p->fds)[iter]); 2483 if (!hbfdp) 2484 return true; 2485 auto sim_fd = hbfdp->getSimFD(); 2486 2487 /** 2488 * Add the sim_fd to tgt_fd translation into trans_map for use 2489 * later when we need to zero the target fd_set structures and 2490 * then update them with hits returned from the host select call. 2491 */ 2492 trans_map[sim_fd] = iter; 2493 2494 /** 2495 * We know that the host file descriptor exists so now we check 2496 * if we need to update the max count for nfds_h before passing 2497 * the duplicated structure into the host. 2498 */ 2499 nfds_h = std::max(nfds_h - 1, sim_fd + 1); 2500 2501 /** 2502 * Add the host file descriptor to the set that we are going to 2503 * pass into the host. 2504 */ 2505 FD_SET(sim_fd, hst_set_entry); 2506 } 2507 return false; 2508 }; 2509 2510 for (int i = 0; i < nfds_t; i++) { 2511 if (fds_read_ptr) { 2512 bool ebadf = try_add_host_set((fd_set*)&*rd_t, &rd_h, i); 2513 if (ebadf) return -EBADF; 2514 } 2515 if (fds_writ_ptr) { 2516 bool ebadf = try_add_host_set((fd_set*)&*wr_t, &wr_h, i); 2517 if (ebadf) return -EBADF; 2518 } 2519 if (fds_excp_ptr) { 2520 bool ebadf = try_add_host_set((fd_set*)&*ex_t, &ex_h, i); 2521 if (ebadf) return -EBADF; 2522 } 2523 } 2524 2525 if (time_val_ptr) { 2526 /** 2527 * It might be possible to decrement the timeval based on some 2528 * derivation of wall clock determined from elapsed simulator ticks 2529 * but that seems like overkill. Rather, we just set the timeval with 2530 * zero timeout. (There is no reason to block during the simulation 2531 * as it only decreases simulator performance.) 2532 */ 2533 tp->tv_sec = 0; 2534 tp->tv_usec = 0; 2535 2536 retval = select(nfds_h, 2537 fds_read_ptr ? &rd_h : nullptr, 2538 fds_writ_ptr ? &wr_h : nullptr, 2539 fds_excp_ptr ? &ex_h : nullptr, 2540 (timeval*)&*tp); 2541 } else { 2542 /** 2543 * If the timeval pointer is null, setup a new timeval structure to 2544 * pass into the host select call. Unfortunately, we will need to 2545 * manually check the return value and throw a retry fault if the 2546 * return value is zero. Allowing the system call to block will 2547 * likely deadlock the event queue. 2548 */ 2549 struct timeval tv = { 0, 0 }; 2550 2551 retval = select(nfds_h, 2552 fds_read_ptr ? &rd_h : nullptr, 2553 fds_writ_ptr ? &wr_h : nullptr, 2554 fds_excp_ptr ? &ex_h : nullptr, 2555 &tv); 2556 2557 if (retval == 0) { 2558 /** 2559 * If blocking indefinitely, check the signal list to see if a 2560 * signal would break the poll out of the retry cycle and try to 2561 * return the signal interrupt instead. 2562 */ 2563 for (auto sig : tc->getSystemPtr()->signalList) 2564 if (sig.receiver == p) 2565 return -EINTR; 2566 return SyscallReturn::retry(); 2567 } 2568 } 2569 2570 if (retval == -1) 2571 return -errno; 2572 2573 FD_ZERO((fd_set*)&*rd_t); 2574 FD_ZERO((fd_set*)&*wr_t); 2575 FD_ZERO((fd_set*)&*ex_t); 2576 2577 /** 2578 * We need to translate the host file descriptor set into a target file 2579 * descriptor set. This involves both our internal process fd array 2580 * and the fd_set defined in header files. 2581 */ 2582 for (int i = 0; i < nfds_h; i++) { 2583 if (fds_read_ptr) { 2584 if (FD_ISSET(i, &rd_h)) 2585 FD_SET(trans_map[i], (fd_set*)&*rd_t); 2586 } 2587 2588 if (fds_writ_ptr) { 2589 if (FD_ISSET(i, &wr_h)) 2590 FD_SET(trans_map[i], (fd_set*)&*wr_t); 2591 } 2592 2593 if (fds_excp_ptr) { 2594 if (FD_ISSET(i, &ex_h)) 2595 FD_SET(trans_map[i], (fd_set*)&*ex_t); 2596 } 2597 } 2598 2599 if (fds_read_ptr) 2600 rd_t.copyOut(tc->getVirtProxy()); 2601 if (fds_writ_ptr) 2602 wr_t.copyOut(tc->getVirtProxy()); 2603 if (fds_excp_ptr) 2604 ex_t.copyOut(tc->getVirtProxy()); 2605 if (time_val_ptr) 2606 tp.copyOut(tc->getVirtProxy()); 2607 2608 return retval; 2609} 2610 2611template <class OS> 2612SyscallReturn 2613readFunc(SyscallDesc *desc, int num, ThreadContext *tc) 2614{ 2615 int index = 0; 2616 auto p = tc->getProcessPtr(); 2617 int tgt_fd = p->getSyscallArg(tc, index); 2618 Addr buf_ptr = p->getSyscallArg(tc, index); 2619 int nbytes = p->getSyscallArg(tc, index); 2620 2621 auto hbfdp = std::dynamic_pointer_cast<HBFDEntry>((*p->fds)[tgt_fd]); 2622 if (!hbfdp) 2623 return -EBADF; 2624 int sim_fd = hbfdp->getSimFD(); 2625 2626 struct pollfd pfd; 2627 pfd.fd = sim_fd; 2628 pfd.events = POLLIN | POLLPRI; 2629 if ((poll(&pfd, 1, 0) == 0) 2630 && !(hbfdp->getFlags() & OS::TGT_O_NONBLOCK)) 2631 return SyscallReturn::retry(); 2632 2633 BufferArg buf_arg(buf_ptr, nbytes); 2634 int bytes_read = read(sim_fd, buf_arg.bufferPtr(), nbytes); 2635 2636 if (bytes_read > 0) 2637 buf_arg.copyOut(tc->getVirtProxy()); 2638 2639 return (bytes_read == -1) ? -errno : bytes_read; 2640} 2641 2642template <class OS> 2643SyscallReturn 2644writeFunc(SyscallDesc *desc, int num, ThreadContext *tc) 2645{ 2646 int index = 0; 2647 auto p = tc->getProcessPtr(); 2648 int tgt_fd = p->getSyscallArg(tc, index); 2649 Addr buf_ptr = p->getSyscallArg(tc, index); 2650 int nbytes = p->getSyscallArg(tc, index); 2651 2652 auto hbfdp = std::dynamic_pointer_cast<HBFDEntry>((*p->fds)[tgt_fd]); 2653 if (!hbfdp) 2654 return -EBADF; 2655 int sim_fd = hbfdp->getSimFD(); 2656 2657 BufferArg buf_arg(buf_ptr, nbytes); 2658 buf_arg.copyIn(tc->getVirtProxy()); 2659 2660 struct pollfd pfd; 2661 pfd.fd = sim_fd; 2662 pfd.events = POLLOUT; 2663 2664 /** 2665 * We don't want to poll on /dev/random. The kernel will not enable the 2666 * file descriptor for writing unless the entropy in the system falls 2667 * below write_wakeup_threshold. This is not guaranteed to happen 2668 * depending on host settings. 2669 */ 2670 auto ffdp = std::dynamic_pointer_cast<FileFDEntry>(hbfdp); 2671 if (ffdp && (ffdp->getFileName() != "/dev/random")) { 2672 if (!poll(&pfd, 1, 0) && !(ffdp->getFlags() & OS::TGT_O_NONBLOCK)) 2673 return SyscallReturn::retry(); 2674 } 2675 2676 int bytes_written = write(sim_fd, buf_arg.bufferPtr(), nbytes); 2677 2678 if (bytes_written != -1) 2679 fsync(sim_fd); 2680 2681 return (bytes_written == -1) ? -errno : bytes_written; 2682} 2683 2684template <class OS> 2685SyscallReturn 2686wait4Func(SyscallDesc *desc, int num, ThreadContext *tc) 2687{ 2688 int index = 0; 2689 auto p = tc->getProcessPtr(); 2690 pid_t pid = p->getSyscallArg(tc, index); 2691 Addr statPtr = p->getSyscallArg(tc, index); 2692 int options = p->getSyscallArg(tc, index); 2693 Addr rusagePtr = p->getSyscallArg(tc, index); 2694 2695 if (rusagePtr) 2696 DPRINTF_SYSCALL(Verbose, "wait4: rusage pointer provided %lx, however " 2697 "functionality not supported. Ignoring rusage pointer.\n", 2698 rusagePtr); 2699 2700 /** 2701 * Currently, wait4 is only implemented so that it will wait for children 2702 * exit conditions which are denoted by a SIGCHLD signals posted into the 2703 * system signal list. We return no additional information via any of the 2704 * parameters supplied to wait4. If nothing is found in the system signal 2705 * list, we will wait indefinitely for SIGCHLD to post by retrying the 2706 * call. 2707 */ 2708 System *sysh = tc->getSystemPtr(); 2709 std::list<BasicSignal>::iterator iter; 2710 for (iter=sysh->signalList.begin(); iter!=sysh->signalList.end(); iter++) { 2711 if (iter->receiver == p) { 2712 if (pid < -1) { 2713 if ((iter->sender->pgid() == -pid) 2714 && (iter->signalValue == OS::TGT_SIGCHLD)) 2715 goto success; 2716 } else if (pid == -1) { 2717 if (iter->signalValue == OS::TGT_SIGCHLD) 2718 goto success; 2719 } else if (pid == 0) { 2720 if ((iter->sender->pgid() == p->pgid()) 2721 && (iter->signalValue == OS::TGT_SIGCHLD)) 2722 goto success; 2723 } else { 2724 if ((iter->sender->pid() == pid) 2725 && (iter->signalValue == OS::TGT_SIGCHLD)) 2726 goto success; 2727 } 2728 } 2729 } 2730 2731 return (options & OS::TGT_WNOHANG) ? 0 : SyscallReturn::retry(); 2732 2733success: 2734 // Set status to EXITED for WIFEXITED evaluations. 2735 const int EXITED = 0; 2736 BufferArg statusBuf(statPtr, sizeof(int)); 2737 *(int *)statusBuf.bufferPtr() = EXITED; 2738 statusBuf.copyOut(tc->getVirtProxy()); 2739 2740 // Return the child PID. 2741 pid_t retval = iter->sender->pid(); 2742 sysh->signalList.erase(iter); 2743 return retval; 2744} 2745 2746template <class OS> 2747SyscallReturn 2748acceptFunc(SyscallDesc *desc, int num, ThreadContext *tc) 2749{ 2750 struct sockaddr sa; 2751 socklen_t addrLen; 2752 int host_fd; 2753 int index = 0; 2754 auto p = tc->getProcessPtr(); 2755 int tgt_fd = p->getSyscallArg(tc, index); 2756 Addr addrPtr = p->getSyscallArg(tc, index); 2757 Addr lenPtr = p->getSyscallArg(tc, index); 2758 2759 BufferArg *lenBufPtr = nullptr; 2760 BufferArg *addrBufPtr = nullptr; 2761 2762 auto sfdp = std::dynamic_pointer_cast<SocketFDEntry>((*p->fds)[tgt_fd]); 2763 if (!sfdp) 2764 return -EBADF; 2765 int sim_fd = sfdp->getSimFD(); 2766 2767 /** 2768 * We poll the socket file descriptor first to guarantee that we do not 2769 * block on our accept call. The socket can be opened without the 2770 * non-blocking flag (it blocks). This will cause deadlocks between 2771 * communicating processes. 2772 */ 2773 struct pollfd pfd; 2774 pfd.fd = sim_fd; 2775 pfd.events = POLLIN | POLLPRI; 2776 if ((poll(&pfd, 1, 0) == 0) 2777 && !(sfdp->getFlags() & OS::TGT_O_NONBLOCK)) 2778 return SyscallReturn::retry(); 2779 2780 if (lenPtr) { 2781 lenBufPtr = new BufferArg(lenPtr, sizeof(socklen_t)); 2782 lenBufPtr->copyIn(tc->getVirtProxy()); 2783 memcpy(&addrLen, (socklen_t *)lenBufPtr->bufferPtr(), 2784 sizeof(socklen_t)); 2785 } 2786 2787 if (addrPtr) { 2788 addrBufPtr = new BufferArg(addrPtr, sizeof(struct sockaddr)); 2789 addrBufPtr->copyIn(tc->getVirtProxy()); 2790 memcpy(&sa, (struct sockaddr *)addrBufPtr->bufferPtr(), 2791 sizeof(struct sockaddr)); 2792 } 2793 2794 host_fd = accept(sim_fd, &sa, &addrLen); 2795 2796 if (host_fd == -1) 2797 return -errno; 2798 2799 if (addrPtr) { 2800 memcpy(addrBufPtr->bufferPtr(), &sa, sizeof(sa)); 2801 addrBufPtr->copyOut(tc->getVirtProxy()); 2802 delete(addrBufPtr); 2803 } 2804 2805 if (lenPtr) { 2806 *(socklen_t *)lenBufPtr->bufferPtr() = addrLen; 2807 lenBufPtr->copyOut(tc->getVirtProxy()); 2808 delete(lenBufPtr); 2809 } 2810 2811 auto afdp = std::make_shared<SocketFDEntry>(host_fd, sfdp->_domain, 2812 sfdp->_type, sfdp->_protocol); 2813 return p->fds->allocFD(afdp); 2814} 2815 2816/// Target eventfd() function. 2817template <class OS> 2818SyscallReturn 2819eventfdFunc(SyscallDesc *desc, int num, ThreadContext *tc) 2820{ 2821#if defined(__linux__) 2822 int index = 0; 2823 auto p = tc->getProcessPtr(); 2824 unsigned initval = p->getSyscallArg(tc, index); 2825 int in_flags = p->getSyscallArg(tc, index); 2826 2827 int sim_fd = eventfd(initval, in_flags); 2828 if (sim_fd == -1) 2829 return -errno; 2830 2831 bool cloexec = in_flags & OS::TGT_O_CLOEXEC; 2832 2833 int flags = cloexec ? OS::TGT_O_CLOEXEC : 0; 2834 flags |= (in_flags & OS::TGT_O_NONBLOCK) ? OS::TGT_O_NONBLOCK : 0; 2835 2836 auto hbfdp = std::make_shared<HBFDEntry>(flags, sim_fd, cloexec); 2837 int tgt_fd = p->fds->allocFD(hbfdp); 2838 return tgt_fd; 2839#else 2840 warnUnsupportedOS("eventfd"); 2841 return -1; 2842#endif 2843} 2844 2845#endif // __SIM_SYSCALL_EMUL_HH__ 2846