syscall_emul.hh revision 12334
1/*
2 * Copyright (c) 2012-2013, 2015 ARM Limited
3 * Copyright (c) 2015 Advanced Micro Devices, Inc.
4 * All rights reserved
5 *
6 * The license below extends only to copyright in the software and shall
7 * not be construed as granting a license to any other intellectual
8 * property including but not limited to intellectual property relating
9 * to a hardware implementation of the functionality of the software
10 * licensed hereunder.  You may use the software subject to the license
11 * terms below provided that you ensure that this notice is replicated
12 * unmodified and in its entirety in all distributions of the software,
13 * modified or unmodified, in source code or in binary form.
14 *
15 * Copyright (c) 2003-2005 The Regents of The University of Michigan
16 * All rights reserved.
17 *
18 * Redistribution and use in source and binary forms, with or without
19 * modification, are permitted provided that the following conditions are
20 * met: redistributions of source code must retain the above copyright
21 * notice, this list of conditions and the following disclaimer;
22 * redistributions in binary form must reproduce the above copyright
23 * notice, this list of conditions and the following disclaimer in the
24 * documentation and/or other materials provided with the distribution;
25 * neither the name of the copyright holders nor the names of its
26 * contributors may be used to endorse or promote products derived from
27 * this software without specific prior written permission.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
30 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
31 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
32 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
33 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
34 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
35 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
39 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
40 *
41 * Authors: Steve Reinhardt
42 *          Kevin Lim
43 */
44
45#ifndef __SIM_SYSCALL_EMUL_HH__
46#define __SIM_SYSCALL_EMUL_HH__
47
48#if (defined(__APPLE__) || defined(__OpenBSD__) ||      \
49     defined(__FreeBSD__) || defined(__CYGWIN__) ||     \
50     defined(__NetBSD__))
51#define NO_STAT64 1
52#else
53#define NO_STAT64 0
54#endif
55
56#if (defined(__APPLE__) || defined(__OpenBSD__) ||      \
57     defined(__FreeBSD__) || defined(__NetBSD__))
58#define NO_STATFS 1
59#else
60#define NO_STATFS 0
61#endif
62
63#if (defined(__APPLE__) || defined(__OpenBSD__) ||      \
64     defined(__FreeBSD__) || defined(__NetBSD__))
65#define NO_FALLOCATE 1
66#else
67#define NO_FALLOCATE 0
68#endif
69
70///
71/// @file syscall_emul.hh
72///
73/// This file defines objects used to emulate syscalls from the target
74/// application on the host machine.
75
76#ifdef __CYGWIN32__
77#include <sys/fcntl.h>
78
79#endif
80#include <fcntl.h>
81#include <sys/mman.h>
82#include <sys/stat.h>
83#if (NO_STATFS == 0)
84#include <sys/statfs.h>
85#else
86#include <sys/mount.h>
87#endif
88#include <sys/time.h>
89#include <sys/uio.h>
90#include <unistd.h>
91
92#include <cerrno>
93#include <memory>
94#include <string>
95
96#include "arch/utility.hh"
97#include "base/intmath.hh"
98#include "base/loader/object_file.hh"
99#include "base/logging.hh"
100#include "base/trace.hh"
101#include "base/types.hh"
102#include "config/the_isa.hh"
103#include "cpu/base.hh"
104#include "cpu/thread_context.hh"
105#include "mem/page_table.hh"
106#include "params/Process.hh"
107#include "sim/emul_driver.hh"
108#include "sim/futex_map.hh"
109#include "sim/process.hh"
110#include "sim/syscall_debug_macros.hh"
111#include "sim/syscall_desc.hh"
112#include "sim/syscall_emul_buf.hh"
113#include "sim/syscall_return.hh"
114
115//////////////////////////////////////////////////////////////////////
116//
117// The following emulation functions are generic enough that they
118// don't need to be recompiled for different emulated OS's.  They are
119// defined in sim/syscall_emul.cc.
120//
121//////////////////////////////////////////////////////////////////////
122
123
124/// Handler for unimplemented syscalls that we haven't thought about.
125SyscallReturn unimplementedFunc(SyscallDesc *desc, int num,
126                                Process *p, ThreadContext *tc);
127
128/// Handler for unimplemented syscalls that we never intend to
129/// implement (signal handling, etc.) and should not affect the correct
130/// behavior of the program.  Print a warning only if the appropriate
131/// trace flag is enabled.  Return success to the target program.
132SyscallReturn ignoreFunc(SyscallDesc *desc, int num,
133                         Process *p, ThreadContext *tc);
134
135// Target fallocateFunc() handler.
136SyscallReturn fallocateFunc(SyscallDesc *desc, int num,
137                            Process *p, ThreadContext *tc);
138
139/// Target exit() handler: terminate current context.
140SyscallReturn exitFunc(SyscallDesc *desc, int num,
141                       Process *p, ThreadContext *tc);
142
143/// Target exit_group() handler: terminate simulation. (exit all threads)
144SyscallReturn exitGroupFunc(SyscallDesc *desc, int num,
145                       Process *p, ThreadContext *tc);
146
147/// Target set_tid_address() handler.
148SyscallReturn setTidAddressFunc(SyscallDesc *desc, int num,
149                                Process *p, ThreadContext *tc);
150
151/// Target getpagesize() handler.
152SyscallReturn getpagesizeFunc(SyscallDesc *desc, int num,
153                              Process *p, ThreadContext *tc);
154
155/// Target brk() handler: set brk address.
156SyscallReturn brkFunc(SyscallDesc *desc, int num,
157                      Process *p, ThreadContext *tc);
158
159/// Target close() handler.
160SyscallReturn closeFunc(SyscallDesc *desc, int num,
161                        Process *p, ThreadContext *tc);
162
163// Target read() handler.
164SyscallReturn readFunc(SyscallDesc *desc, int num,
165                       Process *p, ThreadContext *tc);
166
167/// Target write() handler.
168SyscallReturn writeFunc(SyscallDesc *desc, int num,
169                        Process *p, ThreadContext *tc);
170
171/// Target lseek() handler.
172SyscallReturn lseekFunc(SyscallDesc *desc, int num,
173                        Process *p, ThreadContext *tc);
174
175/// Target _llseek() handler.
176SyscallReturn _llseekFunc(SyscallDesc *desc, int num,
177                          Process *p, ThreadContext *tc);
178
179/// Target munmap() handler.
180SyscallReturn munmapFunc(SyscallDesc *desc, int num,
181                         Process *p, ThreadContext *tc);
182
183/// Target gethostname() handler.
184SyscallReturn gethostnameFunc(SyscallDesc *desc, int num,
185                              Process *p, ThreadContext *tc);
186
187/// Target getcwd() handler.
188SyscallReturn getcwdFunc(SyscallDesc *desc, int num,
189                         Process *p, ThreadContext *tc);
190
191/// Target readlink() handler.
192SyscallReturn readlinkFunc(SyscallDesc *desc, int num,
193                           Process *p, ThreadContext *tc,
194                           int index = 0);
195SyscallReturn readlinkFunc(SyscallDesc *desc, int num,
196                           Process *p, ThreadContext *tc);
197
198/// Target unlink() handler.
199SyscallReturn unlinkHelper(SyscallDesc *desc, int num,
200                           Process *p, ThreadContext *tc,
201                           int index);
202SyscallReturn unlinkFunc(SyscallDesc *desc, int num,
203                         Process *p, ThreadContext *tc);
204
205/// Target mkdir() handler.
206SyscallReturn mkdirFunc(SyscallDesc *desc, int num,
207                        Process *p, ThreadContext *tc);
208
209/// Target rename() handler.
210SyscallReturn renameFunc(SyscallDesc *desc, int num,
211                         Process *p, ThreadContext *tc);
212
213
214/// Target truncate() handler.
215SyscallReturn truncateFunc(SyscallDesc *desc, int num,
216                           Process *p, ThreadContext *tc);
217
218
219/// Target ftruncate() handler.
220SyscallReturn ftruncateFunc(SyscallDesc *desc, int num,
221                            Process *p, ThreadContext *tc);
222
223
224/// Target truncate64() handler.
225SyscallReturn truncate64Func(SyscallDesc *desc, int num,
226                             Process *p, ThreadContext *tc);
227
228/// Target ftruncate64() handler.
229SyscallReturn ftruncate64Func(SyscallDesc *desc, int num,
230                              Process *p, ThreadContext *tc);
231
232
233/// Target umask() handler.
234SyscallReturn umaskFunc(SyscallDesc *desc, int num,
235                        Process *p, ThreadContext *tc);
236
237/// Target gettid() handler.
238SyscallReturn gettidFunc(SyscallDesc *desc, int num,
239                         Process *p, ThreadContext *tc);
240
241/// Target chown() handler.
242SyscallReturn chownFunc(SyscallDesc *desc, int num,
243                        Process *p, ThreadContext *tc);
244
245/// Target setpgid() handler.
246SyscallReturn setpgidFunc(SyscallDesc *desc, int num,
247                          Process *p, ThreadContext *tc);
248
249/// Target fchown() handler.
250SyscallReturn fchownFunc(SyscallDesc *desc, int num,
251                         Process *p, ThreadContext *tc);
252
253/// Target dup() handler.
254SyscallReturn dupFunc(SyscallDesc *desc, int num,
255                      Process *process, ThreadContext *tc);
256
257/// Target dup2() handler.
258SyscallReturn dup2Func(SyscallDesc *desc, int num,
259                       Process *process, ThreadContext *tc);
260
261/// Target fcntl() handler.
262SyscallReturn fcntlFunc(SyscallDesc *desc, int num,
263                        Process *process, ThreadContext *tc);
264
265/// Target fcntl64() handler.
266SyscallReturn fcntl64Func(SyscallDesc *desc, int num,
267                          Process *process, ThreadContext *tc);
268
269/// Target setuid() handler.
270SyscallReturn setuidFunc(SyscallDesc *desc, int num,
271                         Process *p, ThreadContext *tc);
272
273/// Target pipe() handler.
274SyscallReturn pipeFunc(SyscallDesc *desc, int num,
275                       Process *p, ThreadContext *tc);
276
277/// Internal pipe() handler.
278SyscallReturn pipeImpl(SyscallDesc *desc, int num, Process *p,
279                       ThreadContext *tc, bool pseudoPipe);
280
281/// Target getpid() handler.
282SyscallReturn getpidFunc(SyscallDesc *desc, int num,
283                         Process *p, ThreadContext *tc);
284
285/// Target getuid() handler.
286SyscallReturn getuidFunc(SyscallDesc *desc, int num,
287                         Process *p, ThreadContext *tc);
288
289/// Target getgid() handler.
290SyscallReturn getgidFunc(SyscallDesc *desc, int num,
291                         Process *p, ThreadContext *tc);
292
293/// Target getppid() handler.
294SyscallReturn getppidFunc(SyscallDesc *desc, int num,
295                          Process *p, ThreadContext *tc);
296
297/// Target geteuid() handler.
298SyscallReturn geteuidFunc(SyscallDesc *desc, int num,
299                          Process *p, ThreadContext *tc);
300
301/// Target getegid() handler.
302SyscallReturn getegidFunc(SyscallDesc *desc, int num,
303                          Process *p, ThreadContext *tc);
304
305/// Target access() handler
306SyscallReturn accessFunc(SyscallDesc *desc, int num,
307                         Process *p, ThreadContext *tc);
308SyscallReturn accessFunc(SyscallDesc *desc, int num,
309                         Process *p, ThreadContext *tc,
310                         int index);
311
312/// Futex system call
313/// Implemented by Daniel Sanchez
314/// Used by printf's in multi-threaded apps
315template <class OS>
316SyscallReturn
317futexFunc(SyscallDesc *desc, int callnum, Process *process,
318          ThreadContext *tc)
319{
320    using namespace std;
321
322    int index = 0;
323    Addr uaddr = process->getSyscallArg(tc, index);
324    int op = process->getSyscallArg(tc, index);
325    int val = process->getSyscallArg(tc, index);
326
327    /*
328     * Unsupported option that does not affect the correctness of the
329     * application. This is a performance optimization utilized by Linux.
330     */
331    op &= ~OS::TGT_FUTEX_PRIVATE_FLAG;
332
333    FutexMap &futex_map = tc->getSystemPtr()->futexMap;
334
335    if (OS::TGT_FUTEX_WAIT == op) {
336        // Ensure futex system call accessed atomically.
337        BufferArg buf(uaddr, sizeof(int));
338        buf.copyIn(tc->getMemProxy());
339        int mem_val = *(int*)buf.bufferPtr();
340
341        /*
342         * The value in memory at uaddr is not equal with the expected val
343         * (a different thread must have changed it before the system call was
344         * invoked). In this case, we need to throw an error.
345         */
346        if (val != mem_val)
347            return -OS::TGT_EWOULDBLOCK;
348
349        futex_map.suspend(uaddr, process->tgid(), tc);
350
351        return 0;
352    } else if (OS::TGT_FUTEX_WAKE == op) {
353        return futex_map.wakeup(uaddr, process->tgid(), val);
354    }
355
356    warn("futex: op %d not implemented; ignoring.", op);
357    return -ENOSYS;
358}
359
360
361/// Pseudo Funcs  - These functions use a different return convension,
362/// returning a second value in a register other than the normal return register
363SyscallReturn pipePseudoFunc(SyscallDesc *desc, int num,
364                             Process *process, ThreadContext *tc);
365
366/// Target getpidPseudo() handler.
367SyscallReturn getpidPseudoFunc(SyscallDesc *desc, int num,
368                               Process *p, ThreadContext *tc);
369
370/// Target getuidPseudo() handler.
371SyscallReturn getuidPseudoFunc(SyscallDesc *desc, int num,
372                               Process *p, ThreadContext *tc);
373
374/// Target getgidPseudo() handler.
375SyscallReturn getgidPseudoFunc(SyscallDesc *desc, int num,
376                               Process *p, ThreadContext *tc);
377
378
379/// A readable name for 1,000,000, for converting microseconds to seconds.
380const int one_million = 1000000;
381/// A readable name for 1,000,000,000, for converting nanoseconds to seconds.
382const int one_billion = 1000000000;
383
384/// Approximate seconds since the epoch (1/1/1970).  About a billion,
385/// by my reckoning.  We want to keep this a constant (not use the
386/// real-world time) to keep simulations repeatable.
387const unsigned seconds_since_epoch = 1000000000;
388
389/// Helper function to convert current elapsed time to seconds and
390/// microseconds.
391template <class T1, class T2>
392void
393getElapsedTimeMicro(T1 &sec, T2 &usec)
394{
395    uint64_t elapsed_usecs = curTick() / SimClock::Int::us;
396    sec = elapsed_usecs / one_million;
397    usec = elapsed_usecs % one_million;
398}
399
400/// Helper function to convert current elapsed time to seconds and
401/// nanoseconds.
402template <class T1, class T2>
403void
404getElapsedTimeNano(T1 &sec, T2 &nsec)
405{
406    uint64_t elapsed_nsecs = curTick() / SimClock::Int::ns;
407    sec = elapsed_nsecs / one_billion;
408    nsec = elapsed_nsecs % one_billion;
409}
410
411//////////////////////////////////////////////////////////////////////
412//
413// The following emulation functions are generic, but need to be
414// templated to account for differences in types, constants, etc.
415//
416//////////////////////////////////////////////////////////////////////
417
418    typedef struct statfs hst_statfs;
419#if NO_STAT64
420    typedef struct stat hst_stat;
421    typedef struct stat hst_stat64;
422#else
423    typedef struct stat hst_stat;
424    typedef struct stat64 hst_stat64;
425#endif
426
427//// Helper function to convert a host stat buffer to a target stat
428//// buffer.  Also copies the target buffer out to the simulated
429//// memory space.  Used by stat(), fstat(), and lstat().
430
431template <typename target_stat, typename host_stat>
432void
433convertStatBuf(target_stat &tgt, host_stat *host, bool fakeTTY = false)
434{
435    using namespace TheISA;
436
437    if (fakeTTY)
438        tgt->st_dev = 0xA;
439    else
440        tgt->st_dev = host->st_dev;
441    tgt->st_dev = TheISA::htog(tgt->st_dev);
442    tgt->st_ino = host->st_ino;
443    tgt->st_ino = TheISA::htog(tgt->st_ino);
444    tgt->st_mode = host->st_mode;
445    if (fakeTTY) {
446        // Claim to be a character device
447        tgt->st_mode &= ~S_IFMT;    // Clear S_IFMT
448        tgt->st_mode |= S_IFCHR;    // Set S_IFCHR
449    }
450    tgt->st_mode = TheISA::htog(tgt->st_mode);
451    tgt->st_nlink = host->st_nlink;
452    tgt->st_nlink = TheISA::htog(tgt->st_nlink);
453    tgt->st_uid = host->st_uid;
454    tgt->st_uid = TheISA::htog(tgt->st_uid);
455    tgt->st_gid = host->st_gid;
456    tgt->st_gid = TheISA::htog(tgt->st_gid);
457    if (fakeTTY)
458        tgt->st_rdev = 0x880d;
459    else
460        tgt->st_rdev = host->st_rdev;
461    tgt->st_rdev = TheISA::htog(tgt->st_rdev);
462    tgt->st_size = host->st_size;
463    tgt->st_size = TheISA::htog(tgt->st_size);
464    tgt->st_atimeX = host->st_atime;
465    tgt->st_atimeX = TheISA::htog(tgt->st_atimeX);
466    tgt->st_mtimeX = host->st_mtime;
467    tgt->st_mtimeX = TheISA::htog(tgt->st_mtimeX);
468    tgt->st_ctimeX = host->st_ctime;
469    tgt->st_ctimeX = TheISA::htog(tgt->st_ctimeX);
470    // Force the block size to be 8KB. This helps to ensure buffered io works
471    // consistently across different hosts.
472    tgt->st_blksize = 0x2000;
473    tgt->st_blksize = TheISA::htog(tgt->st_blksize);
474    tgt->st_blocks = host->st_blocks;
475    tgt->st_blocks = TheISA::htog(tgt->st_blocks);
476}
477
478// Same for stat64
479
480template <typename target_stat, typename host_stat64>
481void
482convertStat64Buf(target_stat &tgt, host_stat64 *host, bool fakeTTY = false)
483{
484    using namespace TheISA;
485
486    convertStatBuf<target_stat, host_stat64>(tgt, host, fakeTTY);
487#if defined(STAT_HAVE_NSEC)
488    tgt->st_atime_nsec = host->st_atime_nsec;
489    tgt->st_atime_nsec = TheISA::htog(tgt->st_atime_nsec);
490    tgt->st_mtime_nsec = host->st_mtime_nsec;
491    tgt->st_mtime_nsec = TheISA::htog(tgt->st_mtime_nsec);
492    tgt->st_ctime_nsec = host->st_ctime_nsec;
493    tgt->st_ctime_nsec = TheISA::htog(tgt->st_ctime_nsec);
494#else
495    tgt->st_atime_nsec = 0;
496    tgt->st_mtime_nsec = 0;
497    tgt->st_ctime_nsec = 0;
498#endif
499}
500
501// Here are a couple of convenience functions
502template<class OS>
503void
504copyOutStatBuf(SETranslatingPortProxy &mem, Addr addr,
505               hst_stat *host, bool fakeTTY = false)
506{
507    typedef TypedBufferArg<typename OS::tgt_stat> tgt_stat_buf;
508    tgt_stat_buf tgt(addr);
509    convertStatBuf<tgt_stat_buf, hst_stat>(tgt, host, fakeTTY);
510    tgt.copyOut(mem);
511}
512
513template<class OS>
514void
515copyOutStat64Buf(SETranslatingPortProxy &mem, Addr addr,
516                 hst_stat64 *host, bool fakeTTY = false)
517{
518    typedef TypedBufferArg<typename OS::tgt_stat64> tgt_stat_buf;
519    tgt_stat_buf tgt(addr);
520    convertStat64Buf<tgt_stat_buf, hst_stat64>(tgt, host, fakeTTY);
521    tgt.copyOut(mem);
522}
523
524template <class OS>
525void
526copyOutStatfsBuf(SETranslatingPortProxy &mem, Addr addr,
527                 hst_statfs *host)
528{
529    TypedBufferArg<typename OS::tgt_statfs> tgt(addr);
530
531    tgt->f_type = TheISA::htog(host->f_type);
532#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__)
533    tgt->f_bsize = TheISA::htog(host->f_iosize);
534#else
535    tgt->f_bsize = TheISA::htog(host->f_bsize);
536#endif
537    tgt->f_blocks = TheISA::htog(host->f_blocks);
538    tgt->f_bfree = TheISA::htog(host->f_bfree);
539    tgt->f_bavail = TheISA::htog(host->f_bavail);
540    tgt->f_files = TheISA::htog(host->f_files);
541    tgt->f_ffree = TheISA::htog(host->f_ffree);
542    memcpy(&tgt->f_fsid, &host->f_fsid, sizeof(host->f_fsid));
543#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__)
544    tgt->f_namelen = TheISA::htog(host->f_namemax);
545    tgt->f_frsize = TheISA::htog(host->f_bsize);
546#elif defined(__APPLE__)
547    tgt->f_namelen = 0;
548    tgt->f_frsize = 0;
549#else
550    tgt->f_namelen = TheISA::htog(host->f_namelen);
551    tgt->f_frsize = TheISA::htog(host->f_frsize);
552#endif
553#if defined(__linux__)
554    memcpy(&tgt->f_spare, &host->f_spare, sizeof(host->f_spare));
555#else
556    /*
557     * The fields are different sizes per OS. Don't bother with
558     * f_spare or f_reserved on non-Linux for now.
559     */
560    memset(&tgt->f_spare, 0, sizeof(tgt->f_spare));
561#endif
562
563    tgt.copyOut(mem);
564}
565
566/// Target ioctl() handler.  For the most part, programs call ioctl()
567/// only to find out if their stdout is a tty, to determine whether to
568/// do line or block buffering.  We always claim that output fds are
569/// not TTYs to provide repeatable results.
570template <class OS>
571SyscallReturn
572ioctlFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc)
573{
574    int index = 0;
575    int tgt_fd = p->getSyscallArg(tc, index);
576    unsigned req = p->getSyscallArg(tc, index);
577
578    DPRINTF(SyscallVerbose, "ioctl(%d, 0x%x, ...)\n", tgt_fd, req);
579
580    if (OS::isTtyReq(req))
581        return -ENOTTY;
582
583    auto dfdp = std::dynamic_pointer_cast<DeviceFDEntry>((*p->fds)[tgt_fd]);
584    if (!dfdp)
585        return -EBADF;
586
587    /**
588     * If the driver is valid, issue the ioctl through it. Otherwise,
589     * there's an implicit assumption that the device is a TTY type and we
590     * return that we do not have a valid TTY.
591     */
592    EmulatedDriver *emul_driver = dfdp->getDriver();
593    if (emul_driver)
594        return emul_driver->ioctl(p, tc, req);
595
596    /**
597     * For lack of a better return code, return ENOTTY. Ideally, we should
598     * return something better here, but at least we issue the warning.
599     */
600    warn("Unsupported ioctl call (return ENOTTY): ioctl(%d, 0x%x, ...) @ \n",
601         tgt_fd, req, tc->pcState());
602    return -ENOTTY;
603}
604
605template <class OS>
606SyscallReturn
607openImpl(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc,
608         bool isopenat)
609{
610    int index = 0;
611    int tgt_dirfd = -1;
612
613    /**
614     * If using the openat variant, read in the target directory file
615     * descriptor from the simulated process.
616     */
617    if (isopenat)
618        tgt_dirfd = p->getSyscallArg(tc, index);
619
620    /**
621     * Retrieve the simulated process' memory proxy and then read in the path
622     * string from that memory space into the host's working memory space.
623     */
624    std::string path;
625    if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index)))
626        return -EFAULT;
627
628#ifdef __CYGWIN32__
629    int host_flags = O_BINARY;
630#else
631    int host_flags = 0;
632#endif
633    /**
634     * Translate target flags into host flags. Flags exist which are not
635     * ported between architectures which can cause check failures.
636     */
637    int tgt_flags = p->getSyscallArg(tc, index);
638    for (int i = 0; i < OS::NUM_OPEN_FLAGS; i++) {
639        if (tgt_flags & OS::openFlagTable[i].tgtFlag) {
640            tgt_flags &= ~OS::openFlagTable[i].tgtFlag;
641            host_flags |= OS::openFlagTable[i].hostFlag;
642        }
643    }
644    if (tgt_flags) {
645        warn("open%s: cannot decode flags 0x%x",
646             isopenat ? "at" : "", tgt_flags);
647    }
648#ifdef __CYGWIN32__
649    host_flags |= O_BINARY;
650#endif
651
652    int mode = p->getSyscallArg(tc, index);
653
654    /**
655     * If the simulated process called open or openat with AT_FDCWD specified,
656     * take the current working directory value which was passed into the
657     * process class as a Python parameter and append the current path to
658     * create a full path.
659     * Otherwise, openat with a valid target directory file descriptor has
660     * been called. If the path option, which was passed in as a parameter,
661     * is not absolute, retrieve the directory file descriptor's path and
662     * prepend it to the path passed in as a parameter.
663     * In every case, we should have a full path (which is relevant to the
664     * host) to work with after this block has been passed.
665     */
666    if (!isopenat || (isopenat && tgt_dirfd == OS::TGT_AT_FDCWD)) {
667        path = p->fullPath(path);
668    } else if (!startswith(path, "/")) {
669        std::shared_ptr<FDEntry> fdep = ((*p->fds)[tgt_dirfd]);
670        auto ffdp = std::dynamic_pointer_cast<FileFDEntry>(fdep);
671        if (!ffdp)
672            return -EBADF;
673        path.insert(0, ffdp->getFileName());
674    }
675
676    /**
677     * Since this is an emulated environment, we create pseudo file
678     * descriptors for device requests that have been registered with
679     * the process class through Python; this allows us to create a file
680     * descriptor for subsequent ioctl or mmap calls.
681     */
682    if (startswith(path, "/dev/")) {
683        std::string filename = path.substr(strlen("/dev/"));
684        EmulatedDriver *drv = p->findDriver(filename);
685        if (drv) {
686            DPRINTF_SYSCALL(Verbose, "open%s: passing call to "
687                            "driver open with path[%s]\n",
688                            isopenat ? "at" : "", path.c_str());
689            return drv->open(p, tc, mode, host_flags);
690        }
691        /**
692         * Fall through here for pass through to host devices, such
693         * as /dev/zero
694         */
695    }
696
697    /**
698     * Some special paths and files cannot be called on the host and need
699     * to be handled as special cases inside the simulator.
700     * If the full path that was created above does not match any of the
701     * special cases, pass it through to the open call on the host to let
702     * the host open the file on our behalf.
703     * If the host cannot open the file, return the host's error code back
704     * through the system call to the simulated process.
705     */
706    int sim_fd = -1;
707    std::vector<std::string> special_paths =
708            { "/proc/", "/system/", "/sys/", "/platform/", "/etc/passwd" };
709    for (auto entry : special_paths) {
710        if (startswith(path, entry))
711            sim_fd = OS::openSpecialFile(path, p, tc);
712    }
713    if (sim_fd == -1) {
714        sim_fd = open(path.c_str(), host_flags, mode);
715    }
716    if (sim_fd == -1) {
717        int local = -errno;
718        DPRINTF_SYSCALL(Verbose, "open%s: failed -> path:%s\n",
719                        isopenat ? "at" : "", path.c_str());
720        return local;
721    }
722
723    /**
724     * The file was opened successfully and needs to be recorded in the
725     * process' file descriptor array so that it can be retrieved later.
726     * The target file descriptor that is chosen will be the lowest unused
727     * file descriptor.
728     * Return the indirect target file descriptor back to the simulated
729     * process to act as a handle for the opened file.
730     */
731    auto ffdp = std::make_shared<FileFDEntry>(sim_fd, host_flags, path, 0);
732    int tgt_fd = p->fds->allocFD(ffdp);
733    DPRINTF_SYSCALL(Verbose, "open%s: sim_fd[%d], target_fd[%d] -> path:%s\n",
734                    isopenat ? "at" : "", sim_fd, tgt_fd, path.c_str());
735    return tgt_fd;
736}
737
738/// Target open() handler.
739template <class OS>
740SyscallReturn
741openFunc(SyscallDesc *desc, int callnum, Process *process,
742         ThreadContext *tc)
743{
744    return openImpl<OS>(desc, callnum, process, tc, false);
745}
746
747/// Target openat() handler.
748template <class OS>
749SyscallReturn
750openatFunc(SyscallDesc *desc, int callnum, Process *process,
751           ThreadContext *tc)
752{
753    return openImpl<OS>(desc, callnum, process, tc, true);
754}
755
756/// Target unlinkat() handler.
757template <class OS>
758SyscallReturn
759unlinkatFunc(SyscallDesc *desc, int callnum, Process *process,
760             ThreadContext *tc)
761{
762    int index = 0;
763    int dirfd = process->getSyscallArg(tc, index);
764    if (dirfd != OS::TGT_AT_FDCWD)
765        warn("unlinkat: first argument not AT_FDCWD; unlikely to work");
766
767    return unlinkHelper(desc, callnum, process, tc, 1);
768}
769
770/// Target facessat() handler
771template <class OS>
772SyscallReturn
773faccessatFunc(SyscallDesc *desc, int callnum, Process *process,
774              ThreadContext *tc)
775{
776    int index = 0;
777    int dirfd = process->getSyscallArg(tc, index);
778    if (dirfd != OS::TGT_AT_FDCWD)
779        warn("faccessat: first argument not AT_FDCWD; unlikely to work");
780    return accessFunc(desc, callnum, process, tc, 1);
781}
782
783/// Target readlinkat() handler
784template <class OS>
785SyscallReturn
786readlinkatFunc(SyscallDesc *desc, int callnum, Process *process,
787               ThreadContext *tc)
788{
789    int index = 0;
790    int dirfd = process->getSyscallArg(tc, index);
791    if (dirfd != OS::TGT_AT_FDCWD)
792        warn("openat: first argument not AT_FDCWD; unlikely to work");
793    return readlinkFunc(desc, callnum, process, tc, 1);
794}
795
796/// Target renameat() handler.
797template <class OS>
798SyscallReturn
799renameatFunc(SyscallDesc *desc, int callnum, Process *process,
800             ThreadContext *tc)
801{
802    int index = 0;
803
804    int olddirfd = process->getSyscallArg(tc, index);
805    if (olddirfd != OS::TGT_AT_FDCWD)
806        warn("renameat: first argument not AT_FDCWD; unlikely to work");
807
808    std::string old_name;
809
810    if (!tc->getMemProxy().tryReadString(old_name,
811                                         process->getSyscallArg(tc, index)))
812        return -EFAULT;
813
814    int newdirfd = process->getSyscallArg(tc, index);
815    if (newdirfd != OS::TGT_AT_FDCWD)
816        warn("renameat: third argument not AT_FDCWD; unlikely to work");
817
818    std::string new_name;
819
820    if (!tc->getMemProxy().tryReadString(new_name,
821                                         process->getSyscallArg(tc, index)))
822        return -EFAULT;
823
824    // Adjust path for current working directory
825    old_name = process->fullPath(old_name);
826    new_name = process->fullPath(new_name);
827
828    int result = rename(old_name.c_str(), new_name.c_str());
829    return (result == -1) ? -errno : result;
830}
831
832/// Target sysinfo() handler.
833template <class OS>
834SyscallReturn
835sysinfoFunc(SyscallDesc *desc, int callnum, Process *process,
836            ThreadContext *tc)
837{
838
839    int index = 0;
840    TypedBufferArg<typename OS::tgt_sysinfo>
841        sysinfo(process->getSyscallArg(tc, index));
842
843    sysinfo->uptime = seconds_since_epoch;
844    sysinfo->totalram = process->system->memSize();
845    sysinfo->mem_unit = 1;
846
847    sysinfo.copyOut(tc->getMemProxy());
848
849    return 0;
850}
851
852/// Target chmod() handler.
853template <class OS>
854SyscallReturn
855chmodFunc(SyscallDesc *desc, int callnum, Process *process,
856          ThreadContext *tc)
857{
858    std::string path;
859
860    int index = 0;
861    if (!tc->getMemProxy().tryReadString(path,
862                process->getSyscallArg(tc, index))) {
863        return -EFAULT;
864    }
865
866    uint32_t mode = process->getSyscallArg(tc, index);
867    mode_t hostMode = 0;
868
869    // XXX translate mode flags via OS::something???
870    hostMode = mode;
871
872    // Adjust path for current working directory
873    path = process->fullPath(path);
874
875    // do the chmod
876    int result = chmod(path.c_str(), hostMode);
877    if (result < 0)
878        return -errno;
879
880    return 0;
881}
882
883
884/// Target fchmod() handler.
885template <class OS>
886SyscallReturn
887fchmodFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc)
888{
889    int index = 0;
890    int tgt_fd = p->getSyscallArg(tc, index);
891    uint32_t mode = p->getSyscallArg(tc, index);
892
893    auto ffdp = std::dynamic_pointer_cast<FileFDEntry>((*p->fds)[tgt_fd]);
894    if (!ffdp)
895        return -EBADF;
896    int sim_fd = ffdp->getSimFD();
897
898    mode_t hostMode = mode;
899
900    int result = fchmod(sim_fd, hostMode);
901
902    return (result < 0) ? -errno : 0;
903}
904
905/// Target mremap() handler.
906template <class OS>
907SyscallReturn
908mremapFunc(SyscallDesc *desc, int callnum, Process *process, ThreadContext *tc)
909{
910    int index = 0;
911    Addr start = process->getSyscallArg(tc, index);
912    uint64_t old_length = process->getSyscallArg(tc, index);
913    uint64_t new_length = process->getSyscallArg(tc, index);
914    uint64_t flags = process->getSyscallArg(tc, index);
915    uint64_t provided_address = 0;
916    bool use_provided_address = flags & OS::TGT_MREMAP_FIXED;
917
918    if (use_provided_address)
919        provided_address = process->getSyscallArg(tc, index);
920
921    if ((start % TheISA::PageBytes != 0) ||
922        (provided_address % TheISA::PageBytes != 0)) {
923        warn("mremap failing: arguments not page aligned");
924        return -EINVAL;
925    }
926
927    new_length = roundUp(new_length, TheISA::PageBytes);
928
929    if (new_length > old_length) {
930        std::shared_ptr<MemState> mem_state = process->memState;
931        Addr mmap_end = mem_state->getMmapEnd();
932
933        if ((start + old_length) == mmap_end &&
934            (!use_provided_address || provided_address == start)) {
935            // This case cannot occur when growing downward, as
936            // start is greater than or equal to mmap_end.
937            uint64_t diff = new_length - old_length;
938            process->allocateMem(mmap_end, diff);
939            mem_state->setMmapEnd(mmap_end + diff);
940            return start;
941        } else {
942            if (!use_provided_address && !(flags & OS::TGT_MREMAP_MAYMOVE)) {
943                warn("can't remap here and MREMAP_MAYMOVE flag not set\n");
944                return -ENOMEM;
945            } else {
946                uint64_t new_start = provided_address;
947                if (!use_provided_address) {
948                    new_start = process->mmapGrowsDown() ?
949                                mmap_end - new_length : mmap_end;
950                    mmap_end = process->mmapGrowsDown() ?
951                               new_start : mmap_end + new_length;
952                    mem_state->setMmapEnd(mmap_end);
953                }
954
955                process->pTable->remap(start, old_length, new_start);
956                warn("mremapping to new vaddr %08p-%08p, adding %d\n",
957                     new_start, new_start + new_length,
958                     new_length - old_length);
959                // add on the remaining unallocated pages
960                process->allocateMem(new_start + old_length,
961                                     new_length - old_length,
962                                     use_provided_address /* clobber */);
963                if (use_provided_address &&
964                    ((new_start + new_length > mem_state->getMmapEnd() &&
965                      !process->mmapGrowsDown()) ||
966                    (new_start < mem_state->getMmapEnd() &&
967                      process->mmapGrowsDown()))) {
968                    // something fishy going on here, at least notify the user
969                    // @todo: increase mmap_end?
970                    warn("mmap region limit exceeded with MREMAP_FIXED\n");
971                }
972                warn("returning %08p as start\n", new_start);
973                return new_start;
974            }
975        }
976    } else {
977        if (use_provided_address && provided_address != start)
978            process->pTable->remap(start, new_length, provided_address);
979        process->pTable->unmap(start + new_length, old_length - new_length);
980        return use_provided_address ? provided_address : start;
981    }
982}
983
984/// Target stat() handler.
985template <class OS>
986SyscallReturn
987statFunc(SyscallDesc *desc, int callnum, Process *process,
988         ThreadContext *tc)
989{
990    std::string path;
991
992    int index = 0;
993    if (!tc->getMemProxy().tryReadString(path,
994                process->getSyscallArg(tc, index))) {
995        return -EFAULT;
996    }
997    Addr bufPtr = process->getSyscallArg(tc, index);
998
999    // Adjust path for current working directory
1000    path = process->fullPath(path);
1001
1002    struct stat hostBuf;
1003    int result = stat(path.c_str(), &hostBuf);
1004
1005    if (result < 0)
1006        return -errno;
1007
1008    copyOutStatBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
1009
1010    return 0;
1011}
1012
1013
1014/// Target stat64() handler.
1015template <class OS>
1016SyscallReturn
1017stat64Func(SyscallDesc *desc, int callnum, Process *process,
1018           ThreadContext *tc)
1019{
1020    std::string path;
1021
1022    int index = 0;
1023    if (!tc->getMemProxy().tryReadString(path,
1024                process->getSyscallArg(tc, index)))
1025        return -EFAULT;
1026    Addr bufPtr = process->getSyscallArg(tc, index);
1027
1028    // Adjust path for current working directory
1029    path = process->fullPath(path);
1030
1031#if NO_STAT64
1032    struct stat  hostBuf;
1033    int result = stat(path.c_str(), &hostBuf);
1034#else
1035    struct stat64 hostBuf;
1036    int result = stat64(path.c_str(), &hostBuf);
1037#endif
1038
1039    if (result < 0)
1040        return -errno;
1041
1042    copyOutStat64Buf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
1043
1044    return 0;
1045}
1046
1047
1048/// Target fstatat64() handler.
1049template <class OS>
1050SyscallReturn
1051fstatat64Func(SyscallDesc *desc, int callnum, Process *process,
1052              ThreadContext *tc)
1053{
1054    int index = 0;
1055    int dirfd = process->getSyscallArg(tc, index);
1056    if (dirfd != OS::TGT_AT_FDCWD)
1057        warn("fstatat64: first argument not AT_FDCWD; unlikely to work");
1058
1059    std::string path;
1060    if (!tc->getMemProxy().tryReadString(path,
1061                process->getSyscallArg(tc, index)))
1062        return -EFAULT;
1063    Addr bufPtr = process->getSyscallArg(tc, index);
1064
1065    // Adjust path for current working directory
1066    path = process->fullPath(path);
1067
1068#if NO_STAT64
1069    struct stat  hostBuf;
1070    int result = stat(path.c_str(), &hostBuf);
1071#else
1072    struct stat64 hostBuf;
1073    int result = stat64(path.c_str(), &hostBuf);
1074#endif
1075
1076    if (result < 0)
1077        return -errno;
1078
1079    copyOutStat64Buf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
1080
1081    return 0;
1082}
1083
1084
1085/// Target fstat64() handler.
1086template <class OS>
1087SyscallReturn
1088fstat64Func(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc)
1089{
1090    int index = 0;
1091    int tgt_fd = p->getSyscallArg(tc, index);
1092    Addr bufPtr = p->getSyscallArg(tc, index);
1093
1094    auto ffdp = std::dynamic_pointer_cast<FileFDEntry>((*p->fds)[tgt_fd]);
1095    if (!ffdp)
1096        return -EBADF;
1097    int sim_fd = ffdp->getSimFD();
1098
1099#if NO_STAT64
1100    struct stat  hostBuf;
1101    int result = fstat(sim_fd, &hostBuf);
1102#else
1103    struct stat64  hostBuf;
1104    int result = fstat64(sim_fd, &hostBuf);
1105#endif
1106
1107    if (result < 0)
1108        return -errno;
1109
1110    copyOutStat64Buf<OS>(tc->getMemProxy(), bufPtr, &hostBuf, (sim_fd == 1));
1111
1112    return 0;
1113}
1114
1115
1116/// Target lstat() handler.
1117template <class OS>
1118SyscallReturn
1119lstatFunc(SyscallDesc *desc, int callnum, Process *process,
1120          ThreadContext *tc)
1121{
1122    std::string path;
1123
1124    int index = 0;
1125    if (!tc->getMemProxy().tryReadString(path,
1126                process->getSyscallArg(tc, index))) {
1127        return -EFAULT;
1128    }
1129    Addr bufPtr = process->getSyscallArg(tc, index);
1130
1131    // Adjust path for current working directory
1132    path = process->fullPath(path);
1133
1134    struct stat hostBuf;
1135    int result = lstat(path.c_str(), &hostBuf);
1136
1137    if (result < 0)
1138        return -errno;
1139
1140    copyOutStatBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
1141
1142    return 0;
1143}
1144
1145/// Target lstat64() handler.
1146template <class OS>
1147SyscallReturn
1148lstat64Func(SyscallDesc *desc, int callnum, Process *process,
1149            ThreadContext *tc)
1150{
1151    std::string path;
1152
1153    int index = 0;
1154    if (!tc->getMemProxy().tryReadString(path,
1155                process->getSyscallArg(tc, index))) {
1156        return -EFAULT;
1157    }
1158    Addr bufPtr = process->getSyscallArg(tc, index);
1159
1160    // Adjust path for current working directory
1161    path = process->fullPath(path);
1162
1163#if NO_STAT64
1164    struct stat hostBuf;
1165    int result = lstat(path.c_str(), &hostBuf);
1166#else
1167    struct stat64 hostBuf;
1168    int result = lstat64(path.c_str(), &hostBuf);
1169#endif
1170
1171    if (result < 0)
1172        return -errno;
1173
1174    copyOutStat64Buf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
1175
1176    return 0;
1177}
1178
1179/// Target fstat() handler.
1180template <class OS>
1181SyscallReturn
1182fstatFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc)
1183{
1184    int index = 0;
1185    int tgt_fd = p->getSyscallArg(tc, index);
1186    Addr bufPtr = p->getSyscallArg(tc, index);
1187
1188    DPRINTF_SYSCALL(Verbose, "fstat(%d, ...)\n", tgt_fd);
1189
1190    auto ffdp = std::dynamic_pointer_cast<FileFDEntry>((*p->fds)[tgt_fd]);
1191    if (!ffdp)
1192        return -EBADF;
1193    int sim_fd = ffdp->getSimFD();
1194
1195    struct stat hostBuf;
1196    int result = fstat(sim_fd, &hostBuf);
1197
1198    if (result < 0)
1199        return -errno;
1200
1201    copyOutStatBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf, (sim_fd == 1));
1202
1203    return 0;
1204}
1205
1206
1207/// Target statfs() handler.
1208template <class OS>
1209SyscallReturn
1210statfsFunc(SyscallDesc *desc, int callnum, Process *process,
1211           ThreadContext *tc)
1212{
1213#if NO_STATFS
1214    warn("Host OS cannot support calls to statfs. Ignoring syscall");
1215#else
1216    std::string path;
1217
1218    int index = 0;
1219    if (!tc->getMemProxy().tryReadString(path,
1220                process->getSyscallArg(tc, index))) {
1221        return -EFAULT;
1222    }
1223    Addr bufPtr = process->getSyscallArg(tc, index);
1224
1225    // Adjust path for current working directory
1226    path = process->fullPath(path);
1227
1228    struct statfs hostBuf;
1229    int result = statfs(path.c_str(), &hostBuf);
1230
1231    if (result < 0)
1232        return -errno;
1233
1234    copyOutStatfsBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
1235#endif
1236    return 0;
1237}
1238
1239template <class OS>
1240SyscallReturn
1241cloneFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc)
1242{
1243    int index = 0;
1244    TheISA::IntReg flags = p->getSyscallArg(tc, index);
1245    TheISA::IntReg newStack = p->getSyscallArg(tc, index);
1246    Addr ptidPtr = p->getSyscallArg(tc, index);
1247    Addr ctidPtr = p->getSyscallArg(tc, index);
1248    Addr tlsPtr M5_VAR_USED = p->getSyscallArg(tc, index);
1249
1250    if (((flags & OS::TGT_CLONE_SIGHAND)&& !(flags & OS::TGT_CLONE_VM)) ||
1251        ((flags & OS::TGT_CLONE_THREAD) && !(flags & OS::TGT_CLONE_SIGHAND)) ||
1252        ((flags & OS::TGT_CLONE_FS)     &&  (flags & OS::TGT_CLONE_NEWNS)) ||
1253        ((flags & OS::TGT_CLONE_NEWIPC) &&  (flags & OS::TGT_CLONE_SYSVSEM)) ||
1254        ((flags & OS::TGT_CLONE_NEWPID) &&  (flags & OS::TGT_CLONE_THREAD)) ||
1255        ((flags & OS::TGT_CLONE_VM)     && !(newStack)))
1256        return -EINVAL;
1257
1258    ThreadContext *ctc;
1259    if (!(ctc = p->findFreeContext()))
1260        fatal("clone: no spare thread context in system");
1261
1262    /**
1263     * Note that ProcessParams is generated by swig and there are no other
1264     * examples of how to create anything but this default constructor. The
1265     * fields are manually initialized instead of passing parameters to the
1266     * constructor.
1267     */
1268    ProcessParams *pp = new ProcessParams();
1269    pp->executable.assign(*(new std::string(p->progName())));
1270    pp->cmd.push_back(*(new std::string(p->progName())));
1271    pp->system = p->system;
1272    pp->cwd.assign(p->getcwd());
1273    pp->input.assign("stdin");
1274    pp->output.assign("stdout");
1275    pp->errout.assign("stderr");
1276    pp->uid = p->uid();
1277    pp->euid = p->euid();
1278    pp->gid = p->gid();
1279    pp->egid = p->egid();
1280
1281    /* Find the first free PID that's less than the maximum */
1282    std::set<int> const& pids = p->system->PIDs;
1283    int temp_pid = *pids.begin();
1284    do {
1285        temp_pid++;
1286    } while (pids.find(temp_pid) != pids.end());
1287    if (temp_pid >= System::maxPID)
1288        fatal("temp_pid is too large: %d", temp_pid);
1289
1290    pp->pid = temp_pid;
1291    pp->ppid = (flags & OS::TGT_CLONE_THREAD) ? p->ppid() : p->pid();
1292    Process *cp = pp->create();
1293    delete pp;
1294
1295    Process *owner = ctc->getProcessPtr();
1296    ctc->setProcessPtr(cp);
1297    cp->assignThreadContext(ctc->contextId());
1298    owner->revokeThreadContext(ctc->contextId());
1299
1300    if (flags & OS::TGT_CLONE_PARENT_SETTID) {
1301        BufferArg ptidBuf(ptidPtr, sizeof(long));
1302        long *ptid = (long *)ptidBuf.bufferPtr();
1303        *ptid = cp->pid();
1304        ptidBuf.copyOut(tc->getMemProxy());
1305    }
1306
1307    cp->initState();
1308    p->clone(tc, ctc, cp, flags);
1309
1310    if (flags & OS::TGT_CLONE_THREAD) {
1311        delete cp->sigchld;
1312        cp->sigchld = p->sigchld;
1313    } else if (flags & OS::TGT_SIGCHLD) {
1314        *cp->sigchld = true;
1315    }
1316
1317    if (flags & OS::TGT_CLONE_CHILD_SETTID) {
1318        BufferArg ctidBuf(ctidPtr, sizeof(long));
1319        long *ctid = (long *)ctidBuf.bufferPtr();
1320        *ctid = cp->pid();
1321        ctidBuf.copyOut(ctc->getMemProxy());
1322    }
1323
1324    if (flags & OS::TGT_CLONE_CHILD_CLEARTID)
1325        cp->childClearTID = (uint64_t)ctidPtr;
1326
1327    ctc->clearArchRegs();
1328
1329#if THE_ISA == ALPHA_ISA
1330    TheISA::copyMiscRegs(tc, ctc);
1331#elif THE_ISA == SPARC_ISA
1332    TheISA::copyRegs(tc, ctc);
1333    ctc->setIntReg(TheISA::NumIntArchRegs + 6, 0);
1334    ctc->setIntReg(TheISA::NumIntArchRegs + 4, 0);
1335    ctc->setIntReg(TheISA::NumIntArchRegs + 3, TheISA::NWindows - 2);
1336    ctc->setIntReg(TheISA::NumIntArchRegs + 5, TheISA::NWindows);
1337    ctc->setMiscReg(TheISA::MISCREG_CWP, 0);
1338    ctc->setIntReg(TheISA::NumIntArchRegs + 7, 0);
1339    ctc->setMiscRegNoEffect(TheISA::MISCREG_TL, 0);
1340    ctc->setMiscReg(TheISA::MISCREG_ASI, TheISA::ASI_PRIMARY);
1341    for (int y = 8; y < 32; y++)
1342        ctc->setIntReg(y, tc->readIntReg(y));
1343#elif THE_ISA == ARM_ISA or THE_ISA == X86_ISA
1344    TheISA::copyRegs(tc, ctc);
1345#endif
1346
1347#if THE_ISA == X86_ISA
1348    if (flags & OS::TGT_CLONE_SETTLS) {
1349        ctc->setMiscRegNoEffect(TheISA::MISCREG_FS_BASE, tlsPtr);
1350        ctc->setMiscRegNoEffect(TheISA::MISCREG_FS_EFF_BASE, tlsPtr);
1351    }
1352#endif
1353
1354    if (newStack)
1355        ctc->setIntReg(TheISA::StackPointerReg, newStack);
1356
1357    cp->setSyscallReturn(ctc, 0);
1358
1359#if THE_ISA == ALPHA_ISA
1360    ctc->setIntReg(TheISA::SyscallSuccessReg, 0);
1361#elif THE_ISA == SPARC_ISA
1362    tc->setIntReg(TheISA::SyscallPseudoReturnReg, 0);
1363    ctc->setIntReg(TheISA::SyscallPseudoReturnReg, 1);
1364#endif
1365
1366    ctc->pcState(tc->nextInstAddr());
1367    ctc->activate();
1368
1369    return cp->pid();
1370}
1371
1372/// Target fstatfs() handler.
1373template <class OS>
1374SyscallReturn
1375fstatfsFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc)
1376{
1377    int index = 0;
1378    int tgt_fd = p->getSyscallArg(tc, index);
1379    Addr bufPtr = p->getSyscallArg(tc, index);
1380
1381    auto ffdp = std::dynamic_pointer_cast<FileFDEntry>((*p->fds)[tgt_fd]);
1382    if (!ffdp)
1383        return -EBADF;
1384    int sim_fd = ffdp->getSimFD();
1385
1386    struct statfs hostBuf;
1387    int result = fstatfs(sim_fd, &hostBuf);
1388
1389    if (result < 0)
1390        return -errno;
1391
1392    copyOutStatfsBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
1393
1394    return 0;
1395}
1396
1397
1398/// Target writev() handler.
1399template <class OS>
1400SyscallReturn
1401writevFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc)
1402{
1403    int index = 0;
1404    int tgt_fd = p->getSyscallArg(tc, index);
1405
1406    auto hbfdp = std::dynamic_pointer_cast<HBFDEntry>((*p->fds)[tgt_fd]);
1407    if (!hbfdp)
1408        return -EBADF;
1409    int sim_fd = hbfdp->getSimFD();
1410
1411    SETranslatingPortProxy &prox = tc->getMemProxy();
1412    uint64_t tiov_base = p->getSyscallArg(tc, index);
1413    size_t count = p->getSyscallArg(tc, index);
1414    struct iovec hiov[count];
1415    for (size_t i = 0; i < count; ++i) {
1416        typename OS::tgt_iovec tiov;
1417
1418        prox.readBlob(tiov_base + i*sizeof(typename OS::tgt_iovec),
1419                      (uint8_t*)&tiov, sizeof(typename OS::tgt_iovec));
1420        hiov[i].iov_len = TheISA::gtoh(tiov.iov_len);
1421        hiov[i].iov_base = new char [hiov[i].iov_len];
1422        prox.readBlob(TheISA::gtoh(tiov.iov_base), (uint8_t *)hiov[i].iov_base,
1423                      hiov[i].iov_len);
1424    }
1425
1426    int result = writev(sim_fd, hiov, count);
1427
1428    for (size_t i = 0; i < count; ++i)
1429        delete [] (char *)hiov[i].iov_base;
1430
1431    if (result < 0)
1432        return -errno;
1433
1434    return result;
1435}
1436
1437/// Real mmap handler.
1438template <class OS>
1439SyscallReturn
1440mmapImpl(SyscallDesc *desc, int num, Process *p, ThreadContext *tc,
1441         bool is_mmap2)
1442{
1443    int index = 0;
1444    Addr start = p->getSyscallArg(tc, index);
1445    uint64_t length = p->getSyscallArg(tc, index);
1446    int prot = p->getSyscallArg(tc, index);
1447    int tgt_flags = p->getSyscallArg(tc, index);
1448    int tgt_fd = p->getSyscallArg(tc, index);
1449    int offset = p->getSyscallArg(tc, index);
1450
1451    if (is_mmap2)
1452        offset *= TheISA::PageBytes;
1453
1454    if (start & (TheISA::PageBytes - 1) ||
1455        offset & (TheISA::PageBytes - 1) ||
1456        (tgt_flags & OS::TGT_MAP_PRIVATE &&
1457         tgt_flags & OS::TGT_MAP_SHARED) ||
1458        (!(tgt_flags & OS::TGT_MAP_PRIVATE) &&
1459         !(tgt_flags & OS::TGT_MAP_SHARED)) ||
1460        !length) {
1461        return -EINVAL;
1462    }
1463
1464    if ((prot & PROT_WRITE) && (tgt_flags & OS::TGT_MAP_SHARED)) {
1465        // With shared mmaps, there are two cases to consider:
1466        // 1) anonymous: writes should modify the mapping and this should be
1467        // visible to observers who share the mapping. Currently, it's
1468        // difficult to update the shared mapping because there's no
1469        // structure which maintains information about the which virtual
1470        // memory areas are shared. If that structure existed, it would be
1471        // possible to make the translations point to the same frames.
1472        // 2) file-backed: writes should modify the mapping and the file
1473        // which is backed by the mapping. The shared mapping problem is the
1474        // same as what was mentioned about the anonymous mappings. For
1475        // file-backed mappings, the writes to the file are difficult
1476        // because it requires syncing what the mapping holds with the file
1477        // that resides on the host system. So, any write on a real system
1478        // would cause the change to be propagated to the file mapping at
1479        // some point in the future (the inode is tracked along with the
1480        // mapping). This isn't guaranteed to always happen, but it usually
1481        // works well enough. The guarantee is provided by the msync system
1482        // call. We could force the change through with shared mappings with
1483        // a call to msync, but that again would require more information
1484        // than we currently maintain.
1485        warn("mmap: writing to shared mmap region is currently "
1486             "unsupported. The write succeeds on the target, but it "
1487             "will not be propagated to the host or shared mappings");
1488    }
1489
1490    length = roundUp(length, TheISA::PageBytes);
1491
1492    int sim_fd = -1;
1493    uint8_t *pmap = nullptr;
1494    if (!(tgt_flags & OS::TGT_MAP_ANONYMOUS)) {
1495        std::shared_ptr<FDEntry> fdep = (*p->fds)[tgt_fd];
1496
1497        auto dfdp = std::dynamic_pointer_cast<DeviceFDEntry>(fdep);
1498        if (dfdp) {
1499            EmulatedDriver *emul_driver = dfdp->getDriver();
1500            return emul_driver->mmap(p, tc, start, length, prot,
1501                                     tgt_flags, tgt_fd, offset);
1502        }
1503
1504        auto ffdp = std::dynamic_pointer_cast<FileFDEntry>(fdep);
1505        if (!ffdp)
1506            return -EBADF;
1507        sim_fd = ffdp->getSimFD();
1508
1509        pmap = (decltype(pmap))mmap(nullptr, length, PROT_READ, MAP_PRIVATE,
1510                                    sim_fd, offset);
1511
1512        if (pmap == (decltype(pmap))-1) {
1513            warn("mmap: failed to map file into host address space");
1514            return -errno;
1515        }
1516    }
1517
1518    // Extend global mmap region if necessary. Note that we ignore the
1519    // start address unless MAP_FIXED is specified.
1520    if (!(tgt_flags & OS::TGT_MAP_FIXED)) {
1521        std::shared_ptr<MemState> mem_state = p->memState;
1522        Addr mmap_end = mem_state->getMmapEnd();
1523
1524        start = p->mmapGrowsDown() ? mmap_end - length : mmap_end;
1525        mmap_end = p->mmapGrowsDown() ? start : mmap_end + length;
1526
1527        mem_state->setMmapEnd(mmap_end);
1528    }
1529
1530    DPRINTF_SYSCALL(Verbose, " mmap range is 0x%x - 0x%x\n",
1531                    start, start + length - 1);
1532
1533    // We only allow mappings to overwrite existing mappings if
1534    // TGT_MAP_FIXED is set. Otherwise it shouldn't be a problem
1535    // because we ignore the start hint if TGT_MAP_FIXED is not set.
1536    int clobber = tgt_flags & OS::TGT_MAP_FIXED;
1537    if (clobber) {
1538        for (auto tc : p->system->threadContexts) {
1539            // If we might be overwriting old mappings, we need to
1540            // invalidate potentially stale mappings out of the TLBs.
1541            tc->getDTBPtr()->flushAll();
1542            tc->getITBPtr()->flushAll();
1543        }
1544    }
1545
1546    // Allocate physical memory and map it in. If the page table is already
1547    // mapped and clobber is not set, the simulator will issue throw a
1548    // fatal and bail out of the simulation.
1549    p->allocateMem(start, length, clobber);
1550
1551    // Transfer content into target address space.
1552    SETranslatingPortProxy &tp = tc->getMemProxy();
1553    if (tgt_flags & OS::TGT_MAP_ANONYMOUS) {
1554        // In general, we should zero the mapped area for anonymous mappings,
1555        // with something like:
1556        //     tp.memsetBlob(start, 0, length);
1557        // However, given that we don't support sparse mappings, and
1558        // some applications can map a couple of gigabytes of space
1559        // (intending sparse usage), that can get painfully expensive.
1560        // Fortunately, since we don't properly implement munmap either,
1561        // there's no danger of remapping used memory, so for now all
1562        // newly mapped memory should already be zeroed so we can skip it.
1563    } else {
1564        // It is possible to mmap an area larger than a file, however
1565        // accessing unmapped portions the system triggers a "Bus error"
1566        // on the host. We must know when to stop copying the file from
1567        // the host into the target address space.
1568        struct stat file_stat;
1569        if (fstat(sim_fd, &file_stat) > 0)
1570            fatal("mmap: cannot stat file");
1571
1572        // Copy the portion of the file that is resident. This requires
1573        // checking both the mmap size and the filesize that we are
1574        // trying to mmap into this space; the mmap size also depends
1575        // on the specified offset into the file.
1576        uint64_t size = std::min((uint64_t)file_stat.st_size - offset,
1577                                 length);
1578        tp.writeBlob(start, pmap, size);
1579
1580        // Cleanup the mmap region before exiting this function.
1581        munmap(pmap, length);
1582
1583        // Maintain the symbol table for dynamic executables.
1584        // The loader will call mmap to map the images into its address
1585        // space and we intercept that here. We can verify that we are
1586        // executing inside the loader by checking the program counter value.
1587        // XXX: with multiprogrammed workloads or multi-node configurations,
1588        // this will not work since there is a single global symbol table.
1589        ObjectFile *interpreter = p->getInterpreter();
1590        if (interpreter) {
1591            Addr text_start = interpreter->textBase();
1592            Addr text_end = text_start + interpreter->textSize();
1593
1594            Addr pc = tc->pcState().pc();
1595
1596            if (pc >= text_start && pc < text_end) {
1597                std::shared_ptr<FDEntry> fdep = (*p->fds)[tgt_fd];
1598                auto ffdp = std::dynamic_pointer_cast<FileFDEntry>(fdep);
1599                ObjectFile *lib = createObjectFile(ffdp->getFileName());
1600
1601                if (lib) {
1602                    lib->loadAllSymbols(debugSymbolTable,
1603                                        lib->textBase(), start);
1604                }
1605            }
1606        }
1607
1608        // Note that we do not zero out the remainder of the mapping. This
1609        // is done by a real system, but it probably will not affect
1610        // execution (hopefully).
1611    }
1612
1613    return start;
1614}
1615
1616template <class OS>
1617SyscallReturn
1618pwrite64Func(SyscallDesc *desc, int num, Process *p, ThreadContext *tc)
1619{
1620    int index = 0;
1621    int tgt_fd = p->getSyscallArg(tc, index);
1622    Addr bufPtr = p->getSyscallArg(tc, index);
1623    int nbytes = p->getSyscallArg(tc, index);
1624    int offset = p->getSyscallArg(tc, index);
1625
1626    auto ffdp = std::dynamic_pointer_cast<FileFDEntry>((*p->fds)[tgt_fd]);
1627    if (!ffdp)
1628        return -EBADF;
1629    int sim_fd = ffdp->getSimFD();
1630
1631    BufferArg bufArg(bufPtr, nbytes);
1632    bufArg.copyIn(tc->getMemProxy());
1633
1634    int bytes_written = pwrite(sim_fd, bufArg.bufferPtr(), nbytes, offset);
1635
1636    return (bytes_written == -1) ? -errno : bytes_written;
1637}
1638
1639/// Target mmap() handler.
1640template <class OS>
1641SyscallReturn
1642mmapFunc(SyscallDesc *desc, int num, Process *p, ThreadContext *tc)
1643{
1644    return mmapImpl<OS>(desc, num, p, tc, false);
1645}
1646
1647/// Target mmap2() handler.
1648template <class OS>
1649SyscallReturn
1650mmap2Func(SyscallDesc *desc, int num, Process *p, ThreadContext *tc)
1651{
1652    return mmapImpl<OS>(desc, num, p, tc, true);
1653}
1654
1655/// Target getrlimit() handler.
1656template <class OS>
1657SyscallReturn
1658getrlimitFunc(SyscallDesc *desc, int callnum, Process *process,
1659              ThreadContext *tc)
1660{
1661    int index = 0;
1662    unsigned resource = process->getSyscallArg(tc, index);
1663    TypedBufferArg<typename OS::rlimit> rlp(process->getSyscallArg(tc, index));
1664
1665    switch (resource) {
1666      case OS::TGT_RLIMIT_STACK:
1667        // max stack size in bytes: make up a number (8MB for now)
1668        rlp->rlim_cur = rlp->rlim_max = 8 * 1024 * 1024;
1669        rlp->rlim_cur = TheISA::htog(rlp->rlim_cur);
1670        rlp->rlim_max = TheISA::htog(rlp->rlim_max);
1671        break;
1672
1673      case OS::TGT_RLIMIT_DATA:
1674        // max data segment size in bytes: make up a number
1675        rlp->rlim_cur = rlp->rlim_max = 256 * 1024 * 1024;
1676        rlp->rlim_cur = TheISA::htog(rlp->rlim_cur);
1677        rlp->rlim_max = TheISA::htog(rlp->rlim_max);
1678        break;
1679
1680      default:
1681        warn("getrlimit: unimplemented resource %d", resource);
1682        return -EINVAL;
1683        break;
1684    }
1685
1686    rlp.copyOut(tc->getMemProxy());
1687    return 0;
1688}
1689
1690template <class OS>
1691SyscallReturn
1692prlimitFunc(SyscallDesc *desc, int callnum, Process *process,
1693            ThreadContext *tc)
1694{
1695    int index = 0;
1696    if (process->getSyscallArg(tc, index) != 0)
1697    {
1698        warn("prlimit: ignoring rlimits for nonzero pid");
1699        return -EPERM;
1700    }
1701    int resource = process->getSyscallArg(tc, index);
1702    Addr n = process->getSyscallArg(tc, index);
1703    if (n != 0)
1704        warn("prlimit: ignoring new rlimit");
1705    Addr o = process->getSyscallArg(tc, index);
1706    if (o != 0)
1707    {
1708        TypedBufferArg<typename OS::rlimit> rlp(
1709                process->getSyscallArg(tc, index));
1710        switch (resource) {
1711          case OS::TGT_RLIMIT_STACK:
1712            // max stack size in bytes: make up a number (8MB for now)
1713            rlp->rlim_cur = rlp->rlim_max = 8 * 1024 * 1024;
1714            rlp->rlim_cur = TheISA::htog(rlp->rlim_cur);
1715            rlp->rlim_max = TheISA::htog(rlp->rlim_max);
1716            break;
1717          case OS::TGT_RLIMIT_DATA:
1718            // max data segment size in bytes: make up a number
1719            rlp->rlim_cur = rlp->rlim_max = 256*1024*1024;
1720            rlp->rlim_cur = TheISA::htog(rlp->rlim_cur);
1721            rlp->rlim_max = TheISA::htog(rlp->rlim_max);
1722          default:
1723            warn("prlimit: unimplemented resource %d", resource);
1724            return -EINVAL;
1725            break;
1726        }
1727        rlp.copyOut(tc->getMemProxy());
1728    }
1729    return 0;
1730}
1731
1732/// Target clock_gettime() function.
1733template <class OS>
1734SyscallReturn
1735clock_gettimeFunc(SyscallDesc *desc, int num, Process *p, ThreadContext *tc)
1736{
1737    int index = 1;
1738    //int clk_id = p->getSyscallArg(tc, index);
1739    TypedBufferArg<typename OS::timespec> tp(p->getSyscallArg(tc, index));
1740
1741    getElapsedTimeNano(tp->tv_sec, tp->tv_nsec);
1742    tp->tv_sec += seconds_since_epoch;
1743    tp->tv_sec = TheISA::htog(tp->tv_sec);
1744    tp->tv_nsec = TheISA::htog(tp->tv_nsec);
1745
1746    tp.copyOut(tc->getMemProxy());
1747
1748    return 0;
1749}
1750
1751/// Target clock_getres() function.
1752template <class OS>
1753SyscallReturn
1754clock_getresFunc(SyscallDesc *desc, int num, Process *p, ThreadContext *tc)
1755{
1756    int index = 1;
1757    TypedBufferArg<typename OS::timespec> tp(p->getSyscallArg(tc, index));
1758
1759    // Set resolution at ns, which is what clock_gettime() returns
1760    tp->tv_sec = 0;
1761    tp->tv_nsec = 1;
1762
1763    tp.copyOut(tc->getMemProxy());
1764
1765    return 0;
1766}
1767
1768/// Target gettimeofday() handler.
1769template <class OS>
1770SyscallReturn
1771gettimeofdayFunc(SyscallDesc *desc, int callnum, Process *process,
1772                 ThreadContext *tc)
1773{
1774    int index = 0;
1775    TypedBufferArg<typename OS::timeval> tp(process->getSyscallArg(tc, index));
1776
1777    getElapsedTimeMicro(tp->tv_sec, tp->tv_usec);
1778    tp->tv_sec += seconds_since_epoch;
1779    tp->tv_sec = TheISA::htog(tp->tv_sec);
1780    tp->tv_usec = TheISA::htog(tp->tv_usec);
1781
1782    tp.copyOut(tc->getMemProxy());
1783
1784    return 0;
1785}
1786
1787
1788/// Target utimes() handler.
1789template <class OS>
1790SyscallReturn
1791utimesFunc(SyscallDesc *desc, int callnum, Process *process,
1792           ThreadContext *tc)
1793{
1794    std::string path;
1795
1796    int index = 0;
1797    if (!tc->getMemProxy().tryReadString(path,
1798                process->getSyscallArg(tc, index))) {
1799        return -EFAULT;
1800    }
1801
1802    TypedBufferArg<typename OS::timeval [2]>
1803        tp(process->getSyscallArg(tc, index));
1804    tp.copyIn(tc->getMemProxy());
1805
1806    struct timeval hostTimeval[2];
1807    for (int i = 0; i < 2; ++i) {
1808        hostTimeval[i].tv_sec = TheISA::gtoh((*tp)[i].tv_sec);
1809        hostTimeval[i].tv_usec = TheISA::gtoh((*tp)[i].tv_usec);
1810    }
1811
1812    // Adjust path for current working directory
1813    path = process->fullPath(path);
1814
1815    int result = utimes(path.c_str(), hostTimeval);
1816
1817    if (result < 0)
1818        return -errno;
1819
1820    return 0;
1821}
1822
1823template <class OS>
1824SyscallReturn
1825execveFunc(SyscallDesc *desc, int callnum, Process *p, ThreadContext *tc)
1826{
1827    desc->setFlags(0);
1828
1829    int index = 0;
1830    std::string path;
1831    SETranslatingPortProxy & mem_proxy = tc->getMemProxy();
1832    if (!mem_proxy.tryReadString(path, p->getSyscallArg(tc, index)))
1833        return -EFAULT;
1834
1835    if (access(path.c_str(), F_OK) == -1)
1836        return -EACCES;
1837
1838    auto read_in = [](std::vector<std::string> & vect,
1839                      SETranslatingPortProxy & mem_proxy,
1840                      Addr mem_loc)
1841    {
1842        for (int inc = 0; ; inc++) {
1843            BufferArg b((mem_loc + sizeof(Addr) * inc), sizeof(Addr));
1844            b.copyIn(mem_proxy);
1845
1846            if (!*(Addr*)b.bufferPtr())
1847                break;
1848
1849            vect.push_back(std::string());
1850            mem_proxy.tryReadString(vect[inc], *(Addr*)b.bufferPtr());
1851        }
1852    };
1853
1854    /**
1855     * Note that ProcessParams is generated by swig and there are no other
1856     * examples of how to create anything but this default constructor. The
1857     * fields are manually initialized instead of passing parameters to the
1858     * constructor.
1859     */
1860    ProcessParams *pp = new ProcessParams();
1861    pp->executable = path;
1862    Addr argv_mem_loc = p->getSyscallArg(tc, index);
1863    read_in(pp->cmd, mem_proxy, argv_mem_loc);
1864    Addr envp_mem_loc = p->getSyscallArg(tc, index);
1865    read_in(pp->env, mem_proxy, envp_mem_loc);
1866    pp->uid = p->uid();
1867    pp->egid = p->egid();
1868    pp->euid = p->euid();
1869    pp->gid = p->gid();
1870    pp->ppid = p->ppid();
1871    pp->pid = p->pid();
1872    pp->input.assign("cin");
1873    pp->output.assign("cout");
1874    pp->errout.assign("cerr");
1875    pp->cwd.assign(p->getcwd());
1876    pp->system = p->system;
1877    /**
1878     * Prevent process object creation with identical PIDs (which will trip
1879     * a fatal check in Process constructor). The execve call is supposed to
1880     * take over the currently executing process' identity but replace
1881     * whatever it is doing with a new process image. Instead of hijacking
1882     * the process object in the simulator, we create a new process object
1883     * and bind to the previous process' thread below (hijacking the thread).
1884     */
1885    p->system->PIDs.erase(p->pid());
1886    Process *new_p = pp->create();
1887    delete pp;
1888
1889    /**
1890     * Work through the file descriptor array and close any files marked
1891     * close-on-exec.
1892     */
1893    new_p->fds = p->fds;
1894    for (int i = 0; i < new_p->fds->getSize(); i++) {
1895        std::shared_ptr<FDEntry> fdep = (*new_p->fds)[i];
1896        if (fdep && fdep->getCOE())
1897            new_p->fds->closeFDEntry(i);
1898    }
1899
1900    *new_p->sigchld = true;
1901
1902    delete p;
1903    tc->clearArchRegs();
1904    tc->setProcessPtr(new_p);
1905    new_p->assignThreadContext(tc->contextId());
1906    new_p->initState();
1907    tc->activate();
1908    TheISA::PCState pcState = tc->pcState();
1909    tc->setNPC(pcState.instAddr());
1910
1911    desc->setFlags(SyscallDesc::SuppressReturnValue);
1912    return 0;
1913}
1914
1915/// Target getrusage() function.
1916template <class OS>
1917SyscallReturn
1918getrusageFunc(SyscallDesc *desc, int callnum, Process *process,
1919              ThreadContext *tc)
1920{
1921    int index = 0;
1922    int who = process->getSyscallArg(tc, index); // THREAD, SELF, or CHILDREN
1923    TypedBufferArg<typename OS::rusage> rup(process->getSyscallArg(tc, index));
1924
1925    rup->ru_utime.tv_sec = 0;
1926    rup->ru_utime.tv_usec = 0;
1927    rup->ru_stime.tv_sec = 0;
1928    rup->ru_stime.tv_usec = 0;
1929    rup->ru_maxrss = 0;
1930    rup->ru_ixrss = 0;
1931    rup->ru_idrss = 0;
1932    rup->ru_isrss = 0;
1933    rup->ru_minflt = 0;
1934    rup->ru_majflt = 0;
1935    rup->ru_nswap = 0;
1936    rup->ru_inblock = 0;
1937    rup->ru_oublock = 0;
1938    rup->ru_msgsnd = 0;
1939    rup->ru_msgrcv = 0;
1940    rup->ru_nsignals = 0;
1941    rup->ru_nvcsw = 0;
1942    rup->ru_nivcsw = 0;
1943
1944    switch (who) {
1945      case OS::TGT_RUSAGE_SELF:
1946        getElapsedTimeMicro(rup->ru_utime.tv_sec, rup->ru_utime.tv_usec);
1947        rup->ru_utime.tv_sec = TheISA::htog(rup->ru_utime.tv_sec);
1948        rup->ru_utime.tv_usec = TheISA::htog(rup->ru_utime.tv_usec);
1949        break;
1950
1951      case OS::TGT_RUSAGE_CHILDREN:
1952        // do nothing.  We have no child processes, so they take no time.
1953        break;
1954
1955      default:
1956        // don't really handle THREAD or CHILDREN, but just warn and
1957        // plow ahead
1958        warn("getrusage() only supports RUSAGE_SELF.  Parameter %d ignored.",
1959             who);
1960    }
1961
1962    rup.copyOut(tc->getMemProxy());
1963
1964    return 0;
1965}
1966
1967/// Target times() function.
1968template <class OS>
1969SyscallReturn
1970timesFunc(SyscallDesc *desc, int callnum, Process *process,
1971          ThreadContext *tc)
1972{
1973    int index = 0;
1974    TypedBufferArg<typename OS::tms> bufp(process->getSyscallArg(tc, index));
1975
1976    // Fill in the time structure (in clocks)
1977    int64_t clocks = curTick() * OS::M5_SC_CLK_TCK / SimClock::Int::s;
1978    bufp->tms_utime = clocks;
1979    bufp->tms_stime = 0;
1980    bufp->tms_cutime = 0;
1981    bufp->tms_cstime = 0;
1982
1983    // Convert to host endianness
1984    bufp->tms_utime = TheISA::htog(bufp->tms_utime);
1985
1986    // Write back
1987    bufp.copyOut(tc->getMemProxy());
1988
1989    // Return clock ticks since system boot
1990    return clocks;
1991}
1992
1993/// Target time() function.
1994template <class OS>
1995SyscallReturn
1996timeFunc(SyscallDesc *desc, int callnum, Process *process, ThreadContext *tc)
1997{
1998    typename OS::time_t sec, usec;
1999    getElapsedTimeMicro(sec, usec);
2000    sec += seconds_since_epoch;
2001
2002    int index = 0;
2003    Addr taddr = (Addr)process->getSyscallArg(tc, index);
2004    if (taddr != 0) {
2005        typename OS::time_t t = sec;
2006        t = TheISA::htog(t);
2007        SETranslatingPortProxy &p = tc->getMemProxy();
2008        p.writeBlob(taddr, (uint8_t*)&t, (int)sizeof(typename OS::time_t));
2009    }
2010    return sec;
2011}
2012
2013template <class OS>
2014SyscallReturn
2015tgkillFunc(SyscallDesc *desc, int num, Process *process, ThreadContext *tc)
2016{
2017    int index = 0;
2018    int tgid = process->getSyscallArg(tc, index);
2019    int tid = process->getSyscallArg(tc, index);
2020    int sig = process->getSyscallArg(tc, index);
2021
2022    /**
2023     * This system call is intended to allow killing a specific thread
2024     * within an arbitrary thread group if sanctioned with permission checks.
2025     * It's usually true that threads share the termination signal as pointed
2026     * out by the pthread_kill man page and this seems to be the intended
2027     * usage. Due to this being an emulated environment, assume the following:
2028     * Threads are allowed to call tgkill because the EUID for all threads
2029     * should be the same. There is no signal handling mechanism for kernel
2030     * registration of signal handlers since signals are poorly supported in
2031     * emulation mode. Since signal handlers cannot be registered, all
2032     * threads within in a thread group must share the termination signal.
2033     * We never exhaust PIDs so there's no chance of finding the wrong one
2034     * due to PID rollover.
2035     */
2036
2037    System *sys = tc->getSystemPtr();
2038    Process *tgt_proc = nullptr;
2039    for (int i = 0; i < sys->numContexts(); i++) {
2040        Process *temp = sys->threadContexts[i]->getProcessPtr();
2041        if (temp->pid() == tid) {
2042            tgt_proc = temp;
2043            break;
2044        }
2045    }
2046
2047    if (sig != 0 || sig != OS::TGT_SIGABRT)
2048        return -EINVAL;
2049
2050    if (tgt_proc == nullptr)
2051        return -ESRCH;
2052
2053    if (tgid != -1 && tgt_proc->tgid() != tgid)
2054        return -ESRCH;
2055
2056    if (sig == OS::TGT_SIGABRT)
2057        exitGroupFunc(desc, 252, process, tc);
2058
2059    return 0;
2060}
2061
2062
2063#endif // __SIM_SYSCALL_EMUL_HH__
2064