syscall_emul.hh revision 11758:104a404d426e 
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#define NO_STAT64 (defined(__APPLE__) || defined(__OpenBSD__) || \
49  defined(__FreeBSD__) || defined(__CYGWIN__) || \
50  defined(__NetBSD__))
51
52///
53/// @file syscall_emul.hh
54///
55/// This file defines objects used to emulate syscalls from the target
56/// application on the host machine.
57
58#ifdef __CYGWIN32__
59#include <sys/fcntl.h>  // for O_BINARY
60
61#endif
62#include <fcntl.h>
63#include <sys/mman.h>
64#include <sys/stat.h>
65#include <sys/time.h>
66#include <sys/uio.h>
67#include <unistd.h>
68
69#include <cerrno>
70#include <string>
71
72#include "base/chunk_generator.hh"
73#include "base/intmath.hh"      // for RoundUp
74#include "base/loader/object_file.hh"
75#include "base/misc.hh"
76#include "base/trace.hh"
77#include "base/types.hh"
78#include "config/the_isa.hh"
79#include "cpu/base.hh"
80#include "cpu/thread_context.hh"
81#include "debug/SyscallBase.hh"
82#include "debug/SyscallVerbose.hh"
83#include "mem/page_table.hh"
84#include "sim/byteswap.hh"
85#include "sim/emul_driver.hh"
86#include "sim/process.hh"
87#include "sim/syscall_emul_buf.hh"
88#include "sim/syscallreturn.hh"
89#include "sim/system.hh"
90
91// This wrapper macro helps out with readability a bit. FLAGEXT specifies
92// the verbosity and FMT is the message to be appended to the syscall
93// header information. The syscall header information contains the cpuid
94// and thread id.
95#define DPRINTF_SYSCALL(FLAGEXT, FMT, ...)                                  \
96    DPRINTFS(Syscall##FLAGEXT, tc->getCpuPtr(), "T%d : syscall " FMT,       \
97             tc->threadId(), __VA_ARGS__)
98
99///
100/// System call descriptor.
101///
102class SyscallDesc {
103
104  public:
105
106    /// Typedef for target syscall handler functions.
107    typedef SyscallReturn (*FuncPtr)(SyscallDesc *, int num,
108                           LiveProcess *, ThreadContext *);
109
110    const char *name;   //!< Syscall name (e.g., "open").
111    FuncPtr funcPtr;    //!< Pointer to emulation function.
112    int flags;          //!< Flags (see Flags enum).
113    bool warned;        //!< Have we warned about unimplemented syscall?
114
115    /// Flag values for controlling syscall behavior.
116    enum Flags {
117        /// Don't set return regs according to funcPtr return value.
118        /// Used for syscalls with non-standard return conventions
119        /// that explicitly set the ThreadContext regs (e.g.,
120        /// sigreturn).
121        SuppressReturnValue = 1,
122        WarnOnce = 2
123    };
124
125    /// Constructor.
126    SyscallDesc(const char *_name, FuncPtr _funcPtr, int _flags = 0)
127        : name(_name), funcPtr(_funcPtr), flags(_flags), warned(false)
128    {
129    }
130
131    /// Emulate the syscall.  Public interface for calling through funcPtr.
132    void doSyscall(int callnum, LiveProcess *proc, ThreadContext *tc);
133
134    /// Is the WarnOnce flag set?
135    bool warnOnce() const {  return (flags & WarnOnce); }
136};
137
138
139//////////////////////////////////////////////////////////////////////
140//
141// The following emulation functions are generic enough that they
142// don't need to be recompiled for different emulated OS's.  They are
143// defined in sim/syscall_emul.cc.
144//
145//////////////////////////////////////////////////////////////////////
146
147
148/// Handler for unimplemented syscalls that we haven't thought about.
149SyscallReturn unimplementedFunc(SyscallDesc *desc, int num,
150                                LiveProcess *p, ThreadContext *tc);
151
152/// Handler for unimplemented syscalls that we never intend to
153/// implement (signal handling, etc.) and should not affect the correct
154/// behavior of the program.  Print a warning only if the appropriate
155/// trace flag is enabled.  Return success to the target program.
156SyscallReturn ignoreFunc(SyscallDesc *desc, int num,
157                         LiveProcess *p, ThreadContext *tc);
158
159/// Target exit() handler: terminate current context.
160SyscallReturn exitFunc(SyscallDesc *desc, int num,
161                       LiveProcess *p, ThreadContext *tc);
162
163/// Target exit_group() handler: terminate simulation. (exit all threads)
164SyscallReturn exitGroupFunc(SyscallDesc *desc, int num,
165                       LiveProcess *p, ThreadContext *tc);
166
167/// Target getpagesize() handler.
168SyscallReturn getpagesizeFunc(SyscallDesc *desc, int num,
169                              LiveProcess *p, ThreadContext *tc);
170
171/// Target brk() handler: set brk address.
172SyscallReturn brkFunc(SyscallDesc *desc, int num,
173                      LiveProcess *p, ThreadContext *tc);
174
175/// Target close() handler.
176SyscallReturn closeFunc(SyscallDesc *desc, int num,
177                        LiveProcess *p, ThreadContext *tc);
178
179/// Target read() handler.
180SyscallReturn readFunc(SyscallDesc *desc, int num,
181                       LiveProcess *p, ThreadContext *tc);
182
183/// Target write() handler.
184SyscallReturn writeFunc(SyscallDesc *desc, int num,
185                        LiveProcess *p, ThreadContext *tc);
186
187/// Target lseek() handler.
188SyscallReturn lseekFunc(SyscallDesc *desc, int num,
189                        LiveProcess *p, ThreadContext *tc);
190
191/// Target _llseek() handler.
192SyscallReturn _llseekFunc(SyscallDesc *desc, int num,
193                        LiveProcess *p, ThreadContext *tc);
194
195/// Target munmap() handler.
196SyscallReturn munmapFunc(SyscallDesc *desc, int num,
197                         LiveProcess *p, ThreadContext *tc);
198
199/// Target gethostname() handler.
200SyscallReturn gethostnameFunc(SyscallDesc *desc, int num,
201                              LiveProcess *p, ThreadContext *tc);
202
203/// Target getcwd() handler.
204SyscallReturn getcwdFunc(SyscallDesc *desc, int num,
205                         LiveProcess *p, ThreadContext *tc);
206
207/// Target readlink() handler.
208SyscallReturn readlinkFunc(SyscallDesc *desc, int num,
209                           LiveProcess *p, ThreadContext *tc,
210                           int index = 0);
211SyscallReturn readlinkFunc(SyscallDesc *desc, int num,
212                           LiveProcess *p, ThreadContext *tc);
213
214/// Target unlink() handler.
215SyscallReturn unlinkHelper(SyscallDesc *desc, int num,
216                           LiveProcess *p, ThreadContext *tc,
217                           int index);
218SyscallReturn unlinkFunc(SyscallDesc *desc, int num,
219                         LiveProcess *p, ThreadContext *tc);
220
221/// Target mkdir() handler.
222SyscallReturn mkdirFunc(SyscallDesc *desc, int num,
223                        LiveProcess *p, ThreadContext *tc);
224
225/// Target rename() handler.
226SyscallReturn renameFunc(SyscallDesc *desc, int num,
227                         LiveProcess *p, ThreadContext *tc);
228
229
230/// Target truncate() handler.
231SyscallReturn truncateFunc(SyscallDesc *desc, int num,
232                           LiveProcess *p, ThreadContext *tc);
233
234
235/// Target ftruncate() handler.
236SyscallReturn ftruncateFunc(SyscallDesc *desc, int num,
237                            LiveProcess *p, ThreadContext *tc);
238
239
240/// Target truncate64() handler.
241SyscallReturn truncate64Func(SyscallDesc *desc, int num,
242                             LiveProcess *p, ThreadContext *tc);
243
244/// Target ftruncate64() handler.
245SyscallReturn ftruncate64Func(SyscallDesc *desc, int num,
246                              LiveProcess *p, ThreadContext *tc);
247
248
249/// Target umask() handler.
250SyscallReturn umaskFunc(SyscallDesc *desc, int num,
251                        LiveProcess *p, ThreadContext *tc);
252
253
254/// Target chown() handler.
255SyscallReturn chownFunc(SyscallDesc *desc, int num,
256                        LiveProcess *p, ThreadContext *tc);
257
258
259/// Target fchown() handler.
260SyscallReturn fchownFunc(SyscallDesc *desc, int num,
261                         LiveProcess *p, ThreadContext *tc);
262
263/// Target dup() handler.
264SyscallReturn dupFunc(SyscallDesc *desc, int num,
265                      LiveProcess *process, ThreadContext *tc);
266
267/// Target fnctl() handler.
268SyscallReturn fcntlFunc(SyscallDesc *desc, int num,
269                        LiveProcess *process, ThreadContext *tc);
270
271/// Target fcntl64() handler.
272SyscallReturn fcntl64Func(SyscallDesc *desc, int num,
273                        LiveProcess *process, ThreadContext *tc);
274
275/// Target setuid() handler.
276SyscallReturn setuidFunc(SyscallDesc *desc, int num,
277                               LiveProcess *p, ThreadContext *tc);
278
279/// Target getpid() handler.
280SyscallReturn getpidFunc(SyscallDesc *desc, int num,
281                               LiveProcess *p, ThreadContext *tc);
282
283/// Target getuid() handler.
284SyscallReturn getuidFunc(SyscallDesc *desc, int num,
285                               LiveProcess *p, ThreadContext *tc);
286
287/// Target getgid() handler.
288SyscallReturn getgidFunc(SyscallDesc *desc, int num,
289                               LiveProcess *p, ThreadContext *tc);
290
291/// Target getppid() handler.
292SyscallReturn getppidFunc(SyscallDesc *desc, int num,
293                               LiveProcess *p, ThreadContext *tc);
294
295/// Target geteuid() handler.
296SyscallReturn geteuidFunc(SyscallDesc *desc, int num,
297                               LiveProcess *p, ThreadContext *tc);
298
299/// Target getegid() handler.
300SyscallReturn getegidFunc(SyscallDesc *desc, int num,
301                               LiveProcess *p, ThreadContext *tc);
302
303/// Target clone() handler.
304SyscallReturn cloneFunc(SyscallDesc *desc, int num,
305                               LiveProcess *p, ThreadContext *tc);
306
307/// Target access() handler
308SyscallReturn accessFunc(SyscallDesc *desc, int num,
309                               LiveProcess *p, ThreadContext *tc);
310SyscallReturn accessFunc(SyscallDesc *desc, int num,
311                               LiveProcess *p, ThreadContext *tc,
312                               int index);
313
314/// Futex system call
315///  Implemented by Daniel Sanchez
316///  Used by printf's in multi-threaded apps
317template <class OS>
318SyscallReturn
319futexFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
320          ThreadContext *tc)
321{
322    int index_uaddr = 0;
323    int index_op = 1;
324    int index_val = 2;
325    int index_timeout = 3;
326
327    uint64_t uaddr = process->getSyscallArg(tc, index_uaddr);
328    int op = process->getSyscallArg(tc, index_op);
329    int val = process->getSyscallArg(tc, index_val);
330    uint64_t timeout = process->getSyscallArg(tc, index_timeout);
331
332    std::map<uint64_t, std::list<ThreadContext *> * >
333        &futex_map = tc->getSystemPtr()->futexMap;
334
335    DPRINTF(SyscallVerbose, "In sys_futex: Address=%llx, op=%d, val=%d\n",
336            uaddr, op, val);
337
338    op &= ~OS::TGT_FUTEX_PRIVATE_FLAG;
339
340    if (op == OS::TGT_FUTEX_WAIT) {
341        if (timeout != 0) {
342            warn("sys_futex: FUTEX_WAIT with non-null timeout unimplemented;"
343                 "we'll wait indefinitely");
344        }
345
346        uint8_t *buf = new uint8_t[sizeof(int)];
347        tc->getMemProxy().readBlob((Addr)uaddr, buf, (int)sizeof(int));
348        int mem_val = *((int *)buf);
349        delete[] buf;
350
351        if (val != mem_val) {
352            DPRINTF(SyscallVerbose, "sys_futex: FUTEX_WAKE, read: %d, "
353                                    "expected: %d\n", mem_val, val);
354            return -OS::TGT_EWOULDBLOCK;
355        }
356
357        // Queue the thread context
358        std::list<ThreadContext *> * tcWaitList;
359        if (futex_map.count(uaddr)) {
360            tcWaitList = futex_map.find(uaddr)->second;
361        } else {
362            tcWaitList = new std::list<ThreadContext *>();
363            futex_map.insert(std::pair< uint64_t,
364                            std::list<ThreadContext *> * >(uaddr, tcWaitList));
365        }
366        tcWaitList->push_back(tc);
367        DPRINTF(SyscallVerbose, "sys_futex: FUTEX_WAIT, suspending calling "
368                                "thread context\n");
369        tc->suspend();
370        return 0;
371    } else if (op == OS::TGT_FUTEX_WAKE){
372        int wokenUp = 0;
373        std::list<ThreadContext *> * tcWaitList;
374        if (futex_map.count(uaddr)) {
375            tcWaitList = futex_map.find(uaddr)->second;
376            while (tcWaitList->size() > 0 && wokenUp < val) {
377                tcWaitList->front()->activate();
378                tcWaitList->pop_front();
379                wokenUp++;
380            }
381            if (tcWaitList->empty()) {
382                futex_map.erase(uaddr);
383                delete tcWaitList;
384            }
385        }
386        DPRINTF(SyscallVerbose, "sys_futex: FUTEX_WAKE, activated %d waiting "
387                                "thread contexts\n", wokenUp);
388        return wokenUp;
389    } else {
390        warn("sys_futex: op %d is not implemented, just returning...", op);
391        return 0;
392    }
393
394}
395
396
397/// Pseudo Funcs  - These functions use a different return convension,
398/// returning a second value in a register other than the normal return register
399SyscallReturn pipePseudoFunc(SyscallDesc *desc, int num,
400                             LiveProcess *process, ThreadContext *tc);
401
402/// Target getpidPseudo() handler.
403SyscallReturn getpidPseudoFunc(SyscallDesc *desc, int num,
404                               LiveProcess *p, ThreadContext *tc);
405
406/// Target getuidPseudo() handler.
407SyscallReturn getuidPseudoFunc(SyscallDesc *desc, int num,
408                               LiveProcess *p, ThreadContext *tc);
409
410/// Target getgidPseudo() handler.
411SyscallReturn getgidPseudoFunc(SyscallDesc *desc, int num,
412                               LiveProcess *p, ThreadContext *tc);
413
414
415/// A readable name for 1,000,000, for converting microseconds to seconds.
416const int one_million = 1000000;
417/// A readable name for 1,000,000,000, for converting nanoseconds to seconds.
418const int one_billion = 1000000000;
419
420/// Approximate seconds since the epoch (1/1/1970).  About a billion,
421/// by my reckoning.  We want to keep this a constant (not use the
422/// real-world time) to keep simulations repeatable.
423const unsigned seconds_since_epoch = 1000000000;
424
425/// Helper function to convert current elapsed time to seconds and
426/// microseconds.
427template <class T1, class T2>
428void
429getElapsedTimeMicro(T1 &sec, T2 &usec)
430{
431    uint64_t elapsed_usecs = curTick() / SimClock::Int::us;
432    sec = elapsed_usecs / one_million;
433    usec = elapsed_usecs % one_million;
434}
435
436/// Helper function to convert current elapsed time to seconds and
437/// nanoseconds.
438template <class T1, class T2>
439void
440getElapsedTimeNano(T1 &sec, T2 &nsec)
441{
442    uint64_t elapsed_nsecs = curTick() / SimClock::Int::ns;
443    sec = elapsed_nsecs / one_billion;
444    nsec = elapsed_nsecs % one_billion;
445}
446
447//////////////////////////////////////////////////////////////////////
448//
449// The following emulation functions are generic, but need to be
450// templated to account for differences in types, constants, etc.
451//
452//////////////////////////////////////////////////////////////////////
453
454#if NO_STAT64
455    typedef struct stat hst_stat;
456    typedef struct stat hst_stat64;
457#else
458    typedef struct stat hst_stat;
459    typedef struct stat64 hst_stat64;
460#endif
461
462//// Helper function to convert a host stat buffer to a target stat
463//// buffer.  Also copies the target buffer out to the simulated
464//// memory space.  Used by stat(), fstat(), and lstat().
465
466template <typename target_stat, typename host_stat>
467static void
468convertStatBuf(target_stat &tgt, host_stat *host, bool fakeTTY = false)
469{
470    using namespace TheISA;
471
472    if (fakeTTY)
473        tgt->st_dev = 0xA;
474    else
475        tgt->st_dev = host->st_dev;
476    tgt->st_dev = TheISA::htog(tgt->st_dev);
477    tgt->st_ino = host->st_ino;
478    tgt->st_ino = TheISA::htog(tgt->st_ino);
479    tgt->st_mode = host->st_mode;
480    if (fakeTTY) {
481        // Claim to be a character device
482        tgt->st_mode &= ~S_IFMT;    // Clear S_IFMT
483        tgt->st_mode |= S_IFCHR;    // Set S_IFCHR
484    }
485    tgt->st_mode = TheISA::htog(tgt->st_mode);
486    tgt->st_nlink = host->st_nlink;
487    tgt->st_nlink = TheISA::htog(tgt->st_nlink);
488    tgt->st_uid = host->st_uid;
489    tgt->st_uid = TheISA::htog(tgt->st_uid);
490    tgt->st_gid = host->st_gid;
491    tgt->st_gid = TheISA::htog(tgt->st_gid);
492    if (fakeTTY)
493        tgt->st_rdev = 0x880d;
494    else
495        tgt->st_rdev = host->st_rdev;
496    tgt->st_rdev = TheISA::htog(tgt->st_rdev);
497    tgt->st_size = host->st_size;
498    tgt->st_size = TheISA::htog(tgt->st_size);
499    tgt->st_atimeX = host->st_atime;
500    tgt->st_atimeX = TheISA::htog(tgt->st_atimeX);
501    tgt->st_mtimeX = host->st_mtime;
502    tgt->st_mtimeX = TheISA::htog(tgt->st_mtimeX);
503    tgt->st_ctimeX = host->st_ctime;
504    tgt->st_ctimeX = TheISA::htog(tgt->st_ctimeX);
505    // Force the block size to be 8k. This helps to ensure buffered io works
506    // consistently across different hosts.
507    tgt->st_blksize = 0x2000;
508    tgt->st_blksize = TheISA::htog(tgt->st_blksize);
509    tgt->st_blocks = host->st_blocks;
510    tgt->st_blocks = TheISA::htog(tgt->st_blocks);
511}
512
513// Same for stat64
514
515template <typename target_stat, typename host_stat64>
516static void
517convertStat64Buf(target_stat &tgt, host_stat64 *host, bool fakeTTY = false)
518{
519    using namespace TheISA;
520
521    convertStatBuf<target_stat, host_stat64>(tgt, host, fakeTTY);
522#if defined(STAT_HAVE_NSEC)
523    tgt->st_atime_nsec = host->st_atime_nsec;
524    tgt->st_atime_nsec = TheISA::htog(tgt->st_atime_nsec);
525    tgt->st_mtime_nsec = host->st_mtime_nsec;
526    tgt->st_mtime_nsec = TheISA::htog(tgt->st_mtime_nsec);
527    tgt->st_ctime_nsec = host->st_ctime_nsec;
528    tgt->st_ctime_nsec = TheISA::htog(tgt->st_ctime_nsec);
529#else
530    tgt->st_atime_nsec = 0;
531    tgt->st_mtime_nsec = 0;
532    tgt->st_ctime_nsec = 0;
533#endif
534}
535
536//Here are a couple convenience functions
537template<class OS>
538static void
539copyOutStatBuf(SETranslatingPortProxy &mem, Addr addr,
540        hst_stat *host, bool fakeTTY = false)
541{
542    typedef TypedBufferArg<typename OS::tgt_stat> tgt_stat_buf;
543    tgt_stat_buf tgt(addr);
544    convertStatBuf<tgt_stat_buf, hst_stat>(tgt, host, fakeTTY);
545    tgt.copyOut(mem);
546}
547
548template<class OS>
549static void
550copyOutStat64Buf(SETranslatingPortProxy &mem, Addr addr,
551        hst_stat64 *host, bool fakeTTY = false)
552{
553    typedef TypedBufferArg<typename OS::tgt_stat64> tgt_stat_buf;
554    tgt_stat_buf tgt(addr);
555    convertStat64Buf<tgt_stat_buf, hst_stat64>(tgt, host, fakeTTY);
556    tgt.copyOut(mem);
557}
558
559/// Target ioctl() handler.  For the most part, programs call ioctl()
560/// only to find out if their stdout is a tty, to determine whether to
561/// do line or block buffering.  We always claim that output fds are
562/// not TTYs to provide repeatable results.
563template <class OS>
564SyscallReturn
565ioctlFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
566          ThreadContext *tc)
567{
568    int index = 0;
569    int tgt_fd = process->getSyscallArg(tc, index);
570    unsigned req = process->getSyscallArg(tc, index);
571
572    DPRINTF(SyscallVerbose, "ioctl(%d, 0x%x, ...)\n", tgt_fd, req);
573
574    FDEntry *fde = process->getFDEntry(tgt_fd);
575
576    if (fde == NULL) {
577        // doesn't map to any simulator fd: not a valid target fd
578        return -EBADF;
579    }
580
581    if (fde->driver != NULL) {
582        return fde->driver->ioctl(process, tc, req);
583    }
584
585    if (OS::isTtyReq(req)) {
586        return -ENOTTY;
587    }
588
589    warn("Unsupported ioctl call: ioctl(%d, 0x%x, ...) @ \n",
590         tgt_fd, req, tc->pcState());
591    return -ENOTTY;
592}
593
594template <class OS>
595static SyscallReturn
596openFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
597         ThreadContext *tc, int index)
598{
599    std::string path;
600
601    if (!tc->getMemProxy().tryReadString(path,
602                process->getSyscallArg(tc, index)))
603        return -EFAULT;
604
605    int tgtFlags = process->getSyscallArg(tc, index);
606    int mode = process->getSyscallArg(tc, index);
607    int hostFlags = 0;
608
609    // translate open flags
610    for (int i = 0; i < OS::NUM_OPEN_FLAGS; i++) {
611        if (tgtFlags & OS::openFlagTable[i].tgtFlag) {
612            tgtFlags &= ~OS::openFlagTable[i].tgtFlag;
613            hostFlags |= OS::openFlagTable[i].hostFlag;
614        }
615    }
616
617    // any target flags left?
618    if (tgtFlags != 0)
619        warn("Syscall: open: cannot decode flags 0x%x", tgtFlags);
620
621#ifdef __CYGWIN32__
622    hostFlags |= O_BINARY;
623#endif
624
625    // Adjust path for current working directory
626    path = process->fullPath(path);
627
628    DPRINTF(SyscallVerbose, "opening file %s\n", path.c_str());
629
630    if (startswith(path, "/dev/")) {
631        std::string filename = path.substr(strlen("/dev/"));
632        if (filename == "sysdev0") {
633            // This is a memory-mapped high-resolution timer device on Alpha.
634            // We don't support it, so just punt.
635            warn("Ignoring open(%s, ...)\n", path);
636            return -ENOENT;
637        }
638
639        EmulatedDriver *drv = process->findDriver(filename);
640        if (drv != NULL) {
641            // the driver's open method will allocate a fd from the
642            // process if necessary.
643            return drv->open(process, tc, mode, hostFlags);
644        }
645
646        // fall through here for pass through to host devices, such as
647        // /dev/zero
648    }
649
650    int fd;
651    int local_errno;
652    if (startswith(path, "/proc/") || startswith(path, "/system/") ||
653        startswith(path, "/platform/") || startswith(path, "/sys/")) {
654        // It's a proc/sys entry and requires special handling
655        fd = OS::openSpecialFile(path, process, tc);
656        local_errno = ENOENT;
657     } else {
658        // open the file
659        fd = open(path.c_str(), hostFlags, mode);
660        local_errno = errno;
661     }
662
663    if (fd == -1)
664        return -local_errno;
665
666    return process->allocFD(fd, path.c_str(), hostFlags, mode, false);
667}
668
669/// Target open() handler.
670template <class OS>
671SyscallReturn
672openFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
673         ThreadContext *tc)
674{
675    return openFunc<OS>(desc, callnum, process, tc, 0);
676}
677
678/// Target openat() handler.
679template <class OS>
680SyscallReturn
681openatFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
682         ThreadContext *tc)
683{
684    int index = 0;
685    int dirfd = process->getSyscallArg(tc, index);
686    if (dirfd != OS::TGT_AT_FDCWD)
687        warn("openat: first argument not AT_FDCWD; unlikely to work");
688    return openFunc<OS>(desc, callnum, process, tc, 1);
689}
690
691/// Target unlinkat() handler.
692template <class OS>
693SyscallReturn
694unlinkatFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
695             ThreadContext *tc)
696{
697    int index = 0;
698    int dirfd = process->getSyscallArg(tc, index);
699    if (dirfd != OS::TGT_AT_FDCWD)
700        warn("unlinkat: first argument not AT_FDCWD; unlikely to work");
701
702    return unlinkHelper(desc, callnum, process, tc, 1);
703}
704
705/// Target facessat() handler
706template <class OS>
707SyscallReturn
708faccessatFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
709        ThreadContext *tc)
710{
711    int index = 0;
712    int dirfd = process->getSyscallArg(tc, index);
713    if (dirfd != OS::TGT_AT_FDCWD)
714        warn("faccessat: first argument not AT_FDCWD; unlikely to work");
715    return accessFunc(desc, callnum, process, tc, 1);
716}
717
718/// Target readlinkat() handler
719template <class OS>
720SyscallReturn
721readlinkatFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
722        ThreadContext *tc)
723{
724    int index = 0;
725    int dirfd = process->getSyscallArg(tc, index);
726    if (dirfd != OS::TGT_AT_FDCWD)
727        warn("openat: first argument not AT_FDCWD; unlikely to work");
728    return readlinkFunc(desc, callnum, process, tc, 1);
729}
730
731/// Target renameat() handler.
732template <class OS>
733SyscallReturn
734renameatFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
735             ThreadContext *tc)
736{
737    int index = 0;
738
739    int olddirfd = process->getSyscallArg(tc, index);
740    if (olddirfd != OS::TGT_AT_FDCWD)
741        warn("renameat: first argument not AT_FDCWD; unlikely to work");
742
743    std::string old_name;
744
745    if (!tc->getMemProxy().tryReadString(old_name,
746                                         process->getSyscallArg(tc, index)))
747        return -EFAULT;
748
749    int newdirfd = process->getSyscallArg(tc, index);
750    if (newdirfd != OS::TGT_AT_FDCWD)
751        warn("renameat: third argument not AT_FDCWD; unlikely to work");
752
753    std::string new_name;
754
755    if (!tc->getMemProxy().tryReadString(new_name,
756                                         process->getSyscallArg(tc, index)))
757        return -EFAULT;
758
759    // Adjust path for current working directory
760    old_name = process->fullPath(old_name);
761    new_name = process->fullPath(new_name);
762
763    int result = rename(old_name.c_str(), new_name.c_str());
764    return (result == -1) ? -errno : result;
765}
766
767/// Target sysinfo() handler.
768template <class OS>
769SyscallReturn
770sysinfoFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
771         ThreadContext *tc)
772{
773
774    int index = 0;
775    TypedBufferArg<typename OS::tgt_sysinfo>
776        sysinfo(process->getSyscallArg(tc, index));
777
778    sysinfo->uptime = seconds_since_epoch;
779    sysinfo->totalram = process->system->memSize();
780    sysinfo->mem_unit = 1;
781
782    sysinfo.copyOut(tc->getMemProxy());
783
784    return 0;
785}
786
787/// Target chmod() handler.
788template <class OS>
789SyscallReturn
790chmodFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
791          ThreadContext *tc)
792{
793    std::string path;
794
795    int index = 0;
796    if (!tc->getMemProxy().tryReadString(path,
797                process->getSyscallArg(tc, index))) {
798        return -EFAULT;
799    }
800
801    uint32_t mode = process->getSyscallArg(tc, index);
802    mode_t hostMode = 0;
803
804    // XXX translate mode flags via OS::something???
805    hostMode = mode;
806
807    // Adjust path for current working directory
808    path = process->fullPath(path);
809
810    // do the chmod
811    int result = chmod(path.c_str(), hostMode);
812    if (result < 0)
813        return -errno;
814
815    return 0;
816}
817
818
819/// Target fchmod() handler.
820template <class OS>
821SyscallReturn
822fchmodFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
823           ThreadContext *tc)
824{
825    int index = 0;
826    int tgt_fd = process->getSyscallArg(tc, index);
827    uint32_t mode = process->getSyscallArg(tc, index);
828
829    int sim_fd = process->getSimFD(tgt_fd);
830    if (sim_fd < 0)
831        return -EBADF;
832
833    mode_t hostMode = 0;
834
835    // XXX translate mode flags via OS::someting???
836    hostMode = mode;
837
838    // do the fchmod
839    int result = fchmod(sim_fd, hostMode);
840    if (result < 0)
841        return -errno;
842
843    return 0;
844}
845
846/// Target mremap() handler.
847template <class OS>
848SyscallReturn
849mremapFunc(SyscallDesc *desc, int callnum, LiveProcess *process, ThreadContext *tc)
850{
851    int index = 0;
852    Addr start = process->getSyscallArg(tc, index);
853    uint64_t old_length = process->getSyscallArg(tc, index);
854    uint64_t new_length = process->getSyscallArg(tc, index);
855    uint64_t flags = process->getSyscallArg(tc, index);
856    uint64_t provided_address = 0;
857    bool use_provided_address = flags & OS::TGT_MREMAP_FIXED;
858
859    if (use_provided_address)
860        provided_address = process->getSyscallArg(tc, index);
861
862    if ((start % TheISA::PageBytes != 0) ||
863        (provided_address % TheISA::PageBytes != 0)) {
864        warn("mremap failing: arguments not page aligned");
865        return -EINVAL;
866    }
867
868    new_length = roundUp(new_length, TheISA::PageBytes);
869
870    if (new_length > old_length) {
871        if ((start + old_length) == process->mmap_end &&
872            (!use_provided_address || provided_address == start)) {
873            uint64_t diff = new_length - old_length;
874            process->allocateMem(process->mmap_end, diff);
875            process->mmap_end += diff;
876            return start;
877        } else {
878            if (!use_provided_address && !(flags & OS::TGT_MREMAP_MAYMOVE)) {
879                warn("can't remap here and MREMAP_MAYMOVE flag not set\n");
880                return -ENOMEM;
881            } else {
882                uint64_t new_start = use_provided_address ?
883                    provided_address : process->mmap_end;
884                process->pTable->remap(start, old_length, new_start);
885                warn("mremapping to new vaddr %08p-%08p, adding %d\n",
886                     new_start, new_start + new_length,
887                     new_length - old_length);
888                // add on the remaining unallocated pages
889                process->allocateMem(new_start + old_length,
890                                     new_length - old_length,
891                                     use_provided_address /* clobber */);
892                if (!use_provided_address)
893                    process->mmap_end += new_length;
894                if (use_provided_address &&
895                    new_start + new_length > process->mmap_end) {
896                    // something fishy going on here, at least notify the user
897                    // @todo: increase mmap_end?
898                    warn("mmap region limit exceeded with MREMAP_FIXED\n");
899                }
900                warn("returning %08p as start\n", new_start);
901                return new_start;
902            }
903        }
904    } else {
905        if (use_provided_address && provided_address != start)
906            process->pTable->remap(start, new_length, provided_address);
907        process->pTable->unmap(start + new_length, old_length - new_length);
908        return use_provided_address ? provided_address : start;
909    }
910}
911
912/// Target stat() handler.
913template <class OS>
914SyscallReturn
915statFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
916         ThreadContext *tc)
917{
918    std::string path;
919
920    int index = 0;
921    if (!tc->getMemProxy().tryReadString(path,
922                process->getSyscallArg(tc, index))) {
923        return -EFAULT;
924    }
925    Addr bufPtr = process->getSyscallArg(tc, index);
926
927    // Adjust path for current working directory
928    path = process->fullPath(path);
929
930    struct stat hostBuf;
931    int result = stat(path.c_str(), &hostBuf);
932
933    if (result < 0)
934        return -errno;
935
936    copyOutStatBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
937
938    return 0;
939}
940
941
942/// Target stat64() handler.
943template <class OS>
944SyscallReturn
945stat64Func(SyscallDesc *desc, int callnum, LiveProcess *process,
946           ThreadContext *tc)
947{
948    std::string path;
949
950    int index = 0;
951    if (!tc->getMemProxy().tryReadString(path,
952                process->getSyscallArg(tc, index)))
953        return -EFAULT;
954    Addr bufPtr = process->getSyscallArg(tc, index);
955
956    // Adjust path for current working directory
957    path = process->fullPath(path);
958
959#if NO_STAT64
960    struct stat  hostBuf;
961    int result = stat(path.c_str(), &hostBuf);
962#else
963    struct stat64 hostBuf;
964    int result = stat64(path.c_str(), &hostBuf);
965#endif
966
967    if (result < 0)
968        return -errno;
969
970    copyOutStat64Buf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
971
972    return 0;
973}
974
975
976/// Target fstatat64() handler.
977template <class OS>
978SyscallReturn
979fstatat64Func(SyscallDesc *desc, int callnum, LiveProcess *process,
980              ThreadContext *tc)
981{
982    int index = 0;
983    int dirfd = process->getSyscallArg(tc, index);
984    if (dirfd != OS::TGT_AT_FDCWD)
985        warn("fstatat64: first argument not AT_FDCWD; unlikely to work");
986
987    std::string path;
988    if (!tc->getMemProxy().tryReadString(path,
989                process->getSyscallArg(tc, index)))
990        return -EFAULT;
991    Addr bufPtr = process->getSyscallArg(tc, index);
992
993    // Adjust path for current working directory
994    path = process->fullPath(path);
995
996#if NO_STAT64
997    struct stat  hostBuf;
998    int result = stat(path.c_str(), &hostBuf);
999#else
1000    struct stat64 hostBuf;
1001    int result = stat64(path.c_str(), &hostBuf);
1002#endif
1003
1004    if (result < 0)
1005        return -errno;
1006
1007    copyOutStat64Buf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
1008
1009    return 0;
1010}
1011
1012
1013/// Target fstat64() handler.
1014template <class OS>
1015SyscallReturn
1016fstat64Func(SyscallDesc *desc, int callnum, LiveProcess *process,
1017            ThreadContext *tc)
1018{
1019    int index = 0;
1020    int tgt_fd = process->getSyscallArg(tc, index);
1021    Addr bufPtr = process->getSyscallArg(tc, index);
1022
1023    int sim_fd = process->getSimFD(tgt_fd);
1024    if (sim_fd < 0)
1025        return -EBADF;
1026
1027#if NO_STAT64
1028    struct stat  hostBuf;
1029    int result = fstat(sim_fd, &hostBuf);
1030#else
1031    struct stat64  hostBuf;
1032    int result = fstat64(sim_fd, &hostBuf);
1033#endif
1034
1035    if (result < 0)
1036        return -errno;
1037
1038    copyOutStat64Buf<OS>(tc->getMemProxy(), bufPtr, &hostBuf, (sim_fd == 1));
1039
1040    return 0;
1041}
1042
1043
1044/// Target lstat() handler.
1045template <class OS>
1046SyscallReturn
1047lstatFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1048          ThreadContext *tc)
1049{
1050    std::string path;
1051
1052    int index = 0;
1053    if (!tc->getMemProxy().tryReadString(path,
1054                process->getSyscallArg(tc, index))) {
1055        return -EFAULT;
1056    }
1057    Addr bufPtr = process->getSyscallArg(tc, index);
1058
1059    // Adjust path for current working directory
1060    path = process->fullPath(path);
1061
1062    struct stat hostBuf;
1063    int result = lstat(path.c_str(), &hostBuf);
1064
1065    if (result < 0)
1066        return -errno;
1067
1068    copyOutStatBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
1069
1070    return 0;
1071}
1072
1073/// Target lstat64() handler.
1074template <class OS>
1075SyscallReturn
1076lstat64Func(SyscallDesc *desc, int callnum, LiveProcess *process,
1077            ThreadContext *tc)
1078{
1079    std::string path;
1080
1081    int index = 0;
1082    if (!tc->getMemProxy().tryReadString(path,
1083                process->getSyscallArg(tc, index))) {
1084        return -EFAULT;
1085    }
1086    Addr bufPtr = process->getSyscallArg(tc, index);
1087
1088    // Adjust path for current working directory
1089    path = process->fullPath(path);
1090
1091#if NO_STAT64
1092    struct stat hostBuf;
1093    int result = lstat(path.c_str(), &hostBuf);
1094#else
1095    struct stat64 hostBuf;
1096    int result = lstat64(path.c_str(), &hostBuf);
1097#endif
1098
1099    if (result < 0)
1100        return -errno;
1101
1102    copyOutStat64Buf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
1103
1104    return 0;
1105}
1106
1107/// Target fstat() handler.
1108template <class OS>
1109SyscallReturn
1110fstatFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1111          ThreadContext *tc)
1112{
1113    int index = 0;
1114    int tgt_fd = process->getSyscallArg(tc, index);
1115    Addr bufPtr = process->getSyscallArg(tc, index);
1116
1117    DPRINTF_SYSCALL(Verbose, "fstat(%d, ...)\n", tgt_fd);
1118
1119    int sim_fd = process->getSimFD(tgt_fd);
1120    if (sim_fd < 0)
1121        return -EBADF;
1122
1123    struct stat hostBuf;
1124    int result = fstat(sim_fd, &hostBuf);
1125
1126    if (result < 0)
1127        return -errno;
1128
1129    copyOutStatBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf, (sim_fd == 1));
1130
1131    return 0;
1132}
1133
1134
1135/// Target statfs() handler.
1136template <class OS>
1137SyscallReturn
1138statfsFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1139           ThreadContext *tc)
1140{
1141    std::string path;
1142
1143    int index = 0;
1144    if (!tc->getMemProxy().tryReadString(path,
1145                process->getSyscallArg(tc, index))) {
1146        return -EFAULT;
1147    }
1148    Addr bufPtr = process->getSyscallArg(tc, index);
1149
1150    // Adjust path for current working directory
1151    path = process->fullPath(path);
1152
1153    struct statfs hostBuf;
1154    int result = statfs(path.c_str(), &hostBuf);
1155
1156    if (result < 0)
1157        return -errno;
1158
1159    OS::copyOutStatfsBuf(tc->getMemProxy(), bufPtr, &hostBuf);
1160
1161    return 0;
1162}
1163
1164
1165/// Target fstatfs() handler.
1166template <class OS>
1167SyscallReturn
1168fstatfsFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1169            ThreadContext *tc)
1170{
1171    int index = 0;
1172    int tgt_fd = process->getSyscallArg(tc, index);
1173    Addr bufPtr = process->getSyscallArg(tc, index);
1174
1175    int sim_fd = process->getSimFD(tgt_fd);
1176    if (sim_fd < 0)
1177        return -EBADF;
1178
1179    struct statfs hostBuf;
1180    int result = fstatfs(sim_fd, &hostBuf);
1181
1182    if (result < 0)
1183        return -errno;
1184
1185    OS::copyOutStatfsBuf(tc->getMemProxy(), bufPtr, &hostBuf);
1186
1187    return 0;
1188}
1189
1190
1191/// Target writev() handler.
1192template <class OS>
1193SyscallReturn
1194writevFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1195           ThreadContext *tc)
1196{
1197    int index = 0;
1198    int tgt_fd = process->getSyscallArg(tc, index);
1199
1200    int sim_fd = process->getSimFD(tgt_fd);
1201    if (sim_fd < 0)
1202        return -EBADF;
1203
1204    SETranslatingPortProxy &p = tc->getMemProxy();
1205    uint64_t tiov_base = process->getSyscallArg(tc, index);
1206    size_t count = process->getSyscallArg(tc, index);
1207    struct iovec hiov[count];
1208    for (size_t i = 0; i < count; ++i) {
1209        typename OS::tgt_iovec tiov;
1210
1211        p.readBlob(tiov_base + i*sizeof(typename OS::tgt_iovec),
1212                   (uint8_t*)&tiov, sizeof(typename OS::tgt_iovec));
1213        hiov[i].iov_len = TheISA::gtoh(tiov.iov_len);
1214        hiov[i].iov_base = new char [hiov[i].iov_len];
1215        p.readBlob(TheISA::gtoh(tiov.iov_base), (uint8_t *)hiov[i].iov_base,
1216                   hiov[i].iov_len);
1217    }
1218
1219    int result = writev(sim_fd, hiov, count);
1220
1221    for (size_t i = 0; i < count; ++i)
1222        delete [] (char *)hiov[i].iov_base;
1223
1224    if (result < 0)
1225        return -errno;
1226
1227    return result;
1228}
1229
1230/// Real mmap handler.
1231template <class OS>
1232SyscallReturn
1233mmapImpl(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc,
1234         bool is_mmap2)
1235{
1236    int index = 0;
1237    Addr start = p->getSyscallArg(tc, index);
1238    uint64_t length = p->getSyscallArg(tc, index);
1239    int prot = p->getSyscallArg(tc, index);
1240    int tgt_flags = p->getSyscallArg(tc, index);
1241    int tgt_fd = p->getSyscallArg(tc, index);
1242    int offset = p->getSyscallArg(tc, index);
1243
1244    if (is_mmap2)
1245        offset *= TheISA::PageBytes;
1246
1247    if (start & (TheISA::PageBytes - 1) ||
1248        offset & (TheISA::PageBytes - 1) ||
1249        (tgt_flags & OS::TGT_MAP_PRIVATE &&
1250         tgt_flags & OS::TGT_MAP_SHARED) ||
1251        (!(tgt_flags & OS::TGT_MAP_PRIVATE) &&
1252         !(tgt_flags & OS::TGT_MAP_SHARED)) ||
1253        !length) {
1254        return -EINVAL;
1255    }
1256
1257    if ((prot & PROT_WRITE) && (tgt_flags & OS::TGT_MAP_SHARED)) {
1258        // With shared mmaps, there are two cases to consider:
1259        // 1) anonymous: writes should modify the mapping and this should be
1260        // visible to observers who share the mapping. Currently, it's
1261        // difficult to update the shared mapping because there's no
1262        // structure which maintains information about the which virtual
1263        // memory areas are shared. If that structure existed, it would be
1264        // possible to make the translations point to the same frames.
1265        // 2) file-backed: writes should modify the mapping and the file
1266        // which is backed by the mapping. The shared mapping problem is the
1267        // same as what was mentioned about the anonymous mappings. For
1268        // file-backed mappings, the writes to the file are difficult
1269        // because it requires syncing what the mapping holds with the file
1270        // that resides on the host system. So, any write on a real system
1271        // would cause the change to be propagated to the file mapping at
1272        // some point in the future (the inode is tracked along with the
1273        // mapping). This isn't guaranteed to always happen, but it usually
1274        // works well enough. The guarantee is provided by the msync system
1275        // call. We could force the change through with shared mappings with
1276        // a call to msync, but that again would require more information
1277        // than we currently maintain.
1278        warn("mmap: writing to shared mmap region is currently "
1279             "unsupported. The write succeeds on the target, but it "
1280             "will not be propagated to the host or shared mappings");
1281    }
1282
1283    length = roundUp(length, TheISA::PageBytes);
1284
1285    int sim_fd = -1;
1286    uint8_t *pmap = nullptr;
1287    if (!(tgt_flags & OS::TGT_MAP_ANONYMOUS)) {
1288        // Check for EmulatedDriver mmap
1289        FDEntry *fde = p->getFDEntry(tgt_fd);
1290        if (fde == NULL)
1291            return -EBADF;
1292
1293        if (fde->driver != NULL) {
1294            return fde->driver->mmap(p, tc, start, length, prot,
1295                                     tgt_flags, tgt_fd, offset);
1296        }
1297        sim_fd = fde->fd;
1298
1299        if (sim_fd < 0)
1300            return -EBADF;
1301
1302        pmap = (decltype(pmap))mmap(NULL, length, PROT_READ, MAP_PRIVATE,
1303                                    sim_fd, offset);
1304
1305        if (pmap == (decltype(pmap))-1) {
1306            warn("mmap: failed to map file into host address space");
1307            return -errno;
1308        }
1309    }
1310
1311    // Extend global mmap region if necessary. Note that we ignore the
1312    // start address unless MAP_FIXED is specified.
1313    if (!(tgt_flags & OS::TGT_MAP_FIXED)) {
1314        start = p->mmapGrowsDown() ? p->mmap_end - length : p->mmap_end;
1315        p->mmap_end = p->mmapGrowsDown() ? start : p->mmap_end + length;
1316    }
1317
1318    DPRINTF_SYSCALL(Verbose, " mmap range is 0x%x - 0x%x\n",
1319                    start, start + length - 1);
1320
1321    // We only allow mappings to overwrite existing mappings if
1322    // TGT_MAP_FIXED is set. Otherwise it shouldn't be a problem
1323    // because we ignore the start hint if TGT_MAP_FIXED is not set.
1324    int clobber = tgt_flags & OS::TGT_MAP_FIXED;
1325    if (clobber) {
1326        for (auto tc : p->system->threadContexts) {
1327            // If we might be overwriting old mappings, we need to
1328            // invalidate potentially stale mappings out of the TLBs.
1329            tc->getDTBPtr()->flushAll();
1330            tc->getITBPtr()->flushAll();
1331        }
1332    }
1333
1334    // Allocate physical memory and map it in. If the page table is already
1335    // mapped and clobber is not set, the simulator will issue throw a
1336    // fatal and bail out of the simulation.
1337    p->allocateMem(start, length, clobber);
1338
1339    // Transfer content into target address space.
1340    SETranslatingPortProxy &tp = tc->getMemProxy();
1341    if (tgt_flags & OS::TGT_MAP_ANONYMOUS) {
1342        // In general, we should zero the mapped area for anonymous mappings,
1343        // with something like:
1344        //     tp.memsetBlob(start, 0, length);
1345        // However, given that we don't support sparse mappings, and
1346        // some applications can map a couple of gigabytes of space
1347        // (intending sparse usage), that can get painfully expensive.
1348        // Fortunately, since we don't properly implement munmap either,
1349        // there's no danger of remapping used memory, so for now all
1350        // newly mapped memory should already be zeroed so we can skip it.
1351    } else {
1352        // It is possible to mmap an area larger than a file, however
1353        // accessing unmapped portions the system triggers a "Bus error"
1354        // on the host. We must know when to stop copying the file from
1355        // the host into the target address space.
1356        struct stat file_stat;
1357        if (fstat(sim_fd, &file_stat) > 0)
1358            fatal("mmap: cannot stat file");
1359
1360        // Copy the portion of the file that is resident. This requires
1361        // checking both the mmap size and the filesize that we are
1362        // trying to mmap into this space; the mmap size also depends
1363        // on the specified offset into the file.
1364        uint64_t size = std::min((uint64_t)file_stat.st_size - offset,
1365                                 length);
1366        tp.writeBlob(start, pmap, size);
1367
1368        // Cleanup the mmap region before exiting this function.
1369        munmap(pmap, length);
1370
1371        // Maintain the symbol table for dynamic executables.
1372        // The loader will call mmap to map the images into its address
1373        // space and we intercept that here. We can verify that we are
1374        // executing inside the loader by checking the program counter value.
1375        // XXX: with multiprogrammed workloads or multi-node configurations,
1376        // this will not work since there is a single global symbol table.
1377        ObjectFile *interpreter = p->getInterpreter();
1378        if (interpreter) {
1379            Addr text_start = interpreter->textBase();
1380            Addr text_end = text_start + interpreter->textSize();
1381
1382            Addr pc = tc->pcState().pc();
1383
1384            if (pc >= text_start && pc < text_end) {
1385                FDEntry *fde = p->getFDEntry(tgt_fd);
1386
1387                ObjectFile *lib = createObjectFile(fde->filename);
1388
1389                if (lib) {
1390                    lib->loadAllSymbols(debugSymbolTable,
1391                                        lib->textBase(), start);
1392                }
1393            }
1394        }
1395
1396        // Note that we do not zero out the remainder of the mapping. This
1397        // is done by a real system, but it probably will not affect
1398        // execution (hopefully).
1399    }
1400
1401    return start;
1402}
1403
1404template <class OS>
1405SyscallReturn
1406pwrite64Func(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
1407{
1408    int index = 0;
1409    int tgt_fd = p->getSyscallArg(tc, index);
1410    Addr bufPtr = p->getSyscallArg(tc, index);
1411    int nbytes = p->getSyscallArg(tc, index);
1412    int offset = p->getSyscallArg(tc, index);
1413
1414    int sim_fd = p->getSimFD(tgt_fd);
1415    if (sim_fd < 0)
1416        return -EBADF;
1417
1418    BufferArg bufArg(bufPtr, nbytes);
1419    bufArg.copyIn(tc->getMemProxy());
1420
1421    int bytes_written = pwrite(sim_fd, bufArg.bufferPtr(), nbytes, offset);
1422
1423    return (bytes_written == -1) ? -errno : bytes_written;
1424}
1425
1426/// Target mmap() handler.
1427template <class OS>
1428SyscallReturn
1429mmapFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
1430{
1431    return mmapImpl<OS>(desc, num, p, tc, false);
1432}
1433
1434/// Target mmap2() handler.
1435template <class OS>
1436SyscallReturn
1437mmap2Func(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
1438{
1439    return mmapImpl<OS>(desc, num, p, tc, true);
1440}
1441
1442/// Target getrlimit() handler.
1443template <class OS>
1444SyscallReturn
1445getrlimitFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1446        ThreadContext *tc)
1447{
1448    int index = 0;
1449    unsigned resource = process->getSyscallArg(tc, index);
1450    TypedBufferArg<typename OS::rlimit> rlp(process->getSyscallArg(tc, index));
1451
1452    switch (resource) {
1453        case OS::TGT_RLIMIT_STACK:
1454            // max stack size in bytes: make up a number (8MB for now)
1455            rlp->rlim_cur = rlp->rlim_max = 8 * 1024 * 1024;
1456            rlp->rlim_cur = TheISA::htog(rlp->rlim_cur);
1457            rlp->rlim_max = TheISA::htog(rlp->rlim_max);
1458            break;
1459
1460        case OS::TGT_RLIMIT_DATA:
1461            // max data segment size in bytes: make up a number
1462            rlp->rlim_cur = rlp->rlim_max = 256 * 1024 * 1024;
1463            rlp->rlim_cur = TheISA::htog(rlp->rlim_cur);
1464            rlp->rlim_max = TheISA::htog(rlp->rlim_max);
1465            break;
1466
1467        default:
1468            warn("getrlimit: unimplemented resource %d", resource);
1469            return -EINVAL;
1470            break;
1471    }
1472
1473    rlp.copyOut(tc->getMemProxy());
1474    return 0;
1475}
1476
1477/// Target clock_gettime() function.
1478template <class OS>
1479SyscallReturn
1480clock_gettimeFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
1481{
1482    int index = 1;
1483    //int clk_id = p->getSyscallArg(tc, index);
1484    TypedBufferArg<typename OS::timespec> tp(p->getSyscallArg(tc, index));
1485
1486    getElapsedTimeNano(tp->tv_sec, tp->tv_nsec);
1487    tp->tv_sec += seconds_since_epoch;
1488    tp->tv_sec = TheISA::htog(tp->tv_sec);
1489    tp->tv_nsec = TheISA::htog(tp->tv_nsec);
1490
1491    tp.copyOut(tc->getMemProxy());
1492
1493    return 0;
1494}
1495
1496/// Target clock_getres() function.
1497template <class OS>
1498SyscallReturn
1499clock_getresFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
1500{
1501    int index = 1;
1502    TypedBufferArg<typename OS::timespec> tp(p->getSyscallArg(tc, index));
1503
1504    // Set resolution at ns, which is what clock_gettime() returns
1505    tp->tv_sec = 0;
1506    tp->tv_nsec = 1;
1507
1508    tp.copyOut(tc->getMemProxy());
1509
1510    return 0;
1511}
1512
1513/// Target gettimeofday() handler.
1514template <class OS>
1515SyscallReturn
1516gettimeofdayFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1517        ThreadContext *tc)
1518{
1519    int index = 0;
1520    TypedBufferArg<typename OS::timeval> tp(process->getSyscallArg(tc, index));
1521
1522    getElapsedTimeMicro(tp->tv_sec, tp->tv_usec);
1523    tp->tv_sec += seconds_since_epoch;
1524    tp->tv_sec = TheISA::htog(tp->tv_sec);
1525    tp->tv_usec = TheISA::htog(tp->tv_usec);
1526
1527    tp.copyOut(tc->getMemProxy());
1528
1529    return 0;
1530}
1531
1532
1533/// Target utimes() handler.
1534template <class OS>
1535SyscallReturn
1536utimesFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1537           ThreadContext *tc)
1538{
1539    std::string path;
1540
1541    int index = 0;
1542    if (!tc->getMemProxy().tryReadString(path,
1543                process->getSyscallArg(tc, index))) {
1544        return -EFAULT;
1545    }
1546
1547    TypedBufferArg<typename OS::timeval [2]>
1548        tp(process->getSyscallArg(tc, index));
1549    tp.copyIn(tc->getMemProxy());
1550
1551    struct timeval hostTimeval[2];
1552    for (int i = 0; i < 2; ++i)
1553    {
1554        hostTimeval[i].tv_sec = TheISA::gtoh((*tp)[i].tv_sec);
1555        hostTimeval[i].tv_usec = TheISA::gtoh((*tp)[i].tv_usec);
1556    }
1557
1558    // Adjust path for current working directory
1559    path = process->fullPath(path);
1560
1561    int result = utimes(path.c_str(), hostTimeval);
1562
1563    if (result < 0)
1564        return -errno;
1565
1566    return 0;
1567}
1568/// Target getrusage() function.
1569template <class OS>
1570SyscallReturn
1571getrusageFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1572              ThreadContext *tc)
1573{
1574    int index = 0;
1575    int who = process->getSyscallArg(tc, index); // THREAD, SELF, or CHILDREN
1576    TypedBufferArg<typename OS::rusage> rup(process->getSyscallArg(tc, index));
1577
1578    rup->ru_utime.tv_sec = 0;
1579    rup->ru_utime.tv_usec = 0;
1580    rup->ru_stime.tv_sec = 0;
1581    rup->ru_stime.tv_usec = 0;
1582    rup->ru_maxrss = 0;
1583    rup->ru_ixrss = 0;
1584    rup->ru_idrss = 0;
1585    rup->ru_isrss = 0;
1586    rup->ru_minflt = 0;
1587    rup->ru_majflt = 0;
1588    rup->ru_nswap = 0;
1589    rup->ru_inblock = 0;
1590    rup->ru_oublock = 0;
1591    rup->ru_msgsnd = 0;
1592    rup->ru_msgrcv = 0;
1593    rup->ru_nsignals = 0;
1594    rup->ru_nvcsw = 0;
1595    rup->ru_nivcsw = 0;
1596
1597    switch (who) {
1598      case OS::TGT_RUSAGE_SELF:
1599        getElapsedTimeMicro(rup->ru_utime.tv_sec, rup->ru_utime.tv_usec);
1600        rup->ru_utime.tv_sec = TheISA::htog(rup->ru_utime.tv_sec);
1601        rup->ru_utime.tv_usec = TheISA::htog(rup->ru_utime.tv_usec);
1602        break;
1603
1604      case OS::TGT_RUSAGE_CHILDREN:
1605        // do nothing.  We have no child processes, so they take no time.
1606        break;
1607
1608      default:
1609        // don't really handle THREAD or CHILDREN, but just warn and
1610        // plow ahead
1611        warn("getrusage() only supports RUSAGE_SELF.  Parameter %d ignored.",
1612             who);
1613    }
1614
1615    rup.copyOut(tc->getMemProxy());
1616
1617    return 0;
1618}
1619
1620/// Target times() function.
1621template <class OS>
1622SyscallReturn
1623timesFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1624           ThreadContext *tc)
1625{
1626    int index = 0;
1627    TypedBufferArg<typename OS::tms> bufp(process->getSyscallArg(tc, index));
1628
1629    // Fill in the time structure (in clocks)
1630    int64_t clocks = curTick() * OS::M5_SC_CLK_TCK / SimClock::Int::s;
1631    bufp->tms_utime = clocks;
1632    bufp->tms_stime = 0;
1633    bufp->tms_cutime = 0;
1634    bufp->tms_cstime = 0;
1635
1636    // Convert to host endianness
1637    bufp->tms_utime = TheISA::htog(bufp->tms_utime);
1638
1639    // Write back
1640    bufp.copyOut(tc->getMemProxy());
1641
1642    // Return clock ticks since system boot
1643    return clocks;
1644}
1645
1646/// Target time() function.
1647template <class OS>
1648SyscallReturn
1649timeFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1650           ThreadContext *tc)
1651{
1652    typename OS::time_t sec, usec;
1653    getElapsedTimeMicro(sec, usec);
1654    sec += seconds_since_epoch;
1655
1656    int index = 0;
1657    Addr taddr = (Addr)process->getSyscallArg(tc, index);
1658    if (taddr != 0) {
1659        typename OS::time_t t = sec;
1660        t = TheISA::htog(t);
1661        SETranslatingPortProxy &p = tc->getMemProxy();
1662        p.writeBlob(taddr, (uint8_t*)&t, (int)sizeof(typename OS::time_t));
1663    }
1664    return sec;
1665}
1666
1667
1668#endif // __SIM_SYSCALL_EMUL_HH__
1669