syscall_emul.hh revision 11799:e47703369039 
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#define NO_STATFS (defined(__APPLE__) || defined(__OpenBSD__) || \
53  defined(__FreeBSD__) || defined(__NetBSD__))
54
55#define NO_FALLOCATE (defined(__APPLE__) || defined(__OpenBSD__) || \
56  defined(__FreeBSD__) || defined(__NetBSD__))
57
58///
59/// @file syscall_emul.hh
60///
61/// This file defines objects used to emulate syscalls from the target
62/// application on the host machine.
63
64#ifdef __CYGWIN32__
65#include <sys/fcntl.h>  // for O_BINARY
66
67#endif
68#include <fcntl.h>
69#include <sys/mman.h>
70#include <sys/stat.h>
71#if (NO_STATFS == 0)
72#include <sys/statfs.h>
73#endif
74#include <sys/time.h>
75#include <sys/uio.h>
76#include <unistd.h>
77
78#include <cerrno>
79#include <string>
80
81#include "base/chunk_generator.hh"
82#include "base/intmath.hh"      // for RoundUp
83#include "base/loader/object_file.hh"
84#include "base/misc.hh"
85#include "base/trace.hh"
86#include "base/types.hh"
87#include "config/the_isa.hh"
88#include "cpu/base.hh"
89#include "cpu/thread_context.hh"
90#include "mem/page_table.hh"
91#include "sim/byteswap.hh"
92#include "sim/emul_driver.hh"
93#include "sim/process.hh"
94#include "sim/syscall_debug_macros.hh"
95#include "sim/syscall_emul_buf.hh"
96#include "sim/syscall_return.hh"
97#include "sim/system.hh"
98
99class SyscallDesc;
100
101//////////////////////////////////////////////////////////////////////
102//
103// The following emulation functions are generic enough that they
104// don't need to be recompiled for different emulated OS's.  They are
105// defined in sim/syscall_emul.cc.
106//
107//////////////////////////////////////////////////////////////////////
108
109
110/// Handler for unimplemented syscalls that we haven't thought about.
111SyscallReturn unimplementedFunc(SyscallDesc *desc, int num,
112                                LiveProcess *p, ThreadContext *tc);
113
114/// Handler for unimplemented syscalls that we never intend to
115/// implement (signal handling, etc.) and should not affect the correct
116/// behavior of the program.  Print a warning only if the appropriate
117/// trace flag is enabled.  Return success to the target program.
118SyscallReturn ignoreFunc(SyscallDesc *desc, int num,
119                         LiveProcess *p, ThreadContext *tc);
120
121// Target fallocateFunc() handler.
122SyscallReturn fallocateFunc(SyscallDesc *desc, int num,
123                            LiveProcess *p, ThreadContext *tc);
124
125/// Target exit() handler: terminate current context.
126SyscallReturn exitFunc(SyscallDesc *desc, int num,
127                       LiveProcess *p, ThreadContext *tc);
128
129/// Target exit_group() handler: terminate simulation. (exit all threads)
130SyscallReturn exitGroupFunc(SyscallDesc *desc, int num,
131                       LiveProcess *p, ThreadContext *tc);
132
133/// Target getpagesize() handler.
134SyscallReturn getpagesizeFunc(SyscallDesc *desc, int num,
135                              LiveProcess *p, ThreadContext *tc);
136
137/// Target brk() handler: set brk address.
138SyscallReturn brkFunc(SyscallDesc *desc, int num,
139                      LiveProcess *p, ThreadContext *tc);
140
141/// Target close() handler.
142SyscallReturn closeFunc(SyscallDesc *desc, int num,
143                        LiveProcess *p, ThreadContext *tc);
144
145/// Target read() handler.
146SyscallReturn readFunc(SyscallDesc *desc, int num,
147                       LiveProcess *p, ThreadContext *tc);
148
149/// Target write() handler.
150SyscallReturn writeFunc(SyscallDesc *desc, int num,
151                        LiveProcess *p, ThreadContext *tc);
152
153/// Target lseek() handler.
154SyscallReturn lseekFunc(SyscallDesc *desc, int num,
155                        LiveProcess *p, ThreadContext *tc);
156
157/// Target _llseek() handler.
158SyscallReturn _llseekFunc(SyscallDesc *desc, int num,
159                        LiveProcess *p, ThreadContext *tc);
160
161/// Target munmap() handler.
162SyscallReturn munmapFunc(SyscallDesc *desc, int num,
163                         LiveProcess *p, ThreadContext *tc);
164
165/// Target gethostname() handler.
166SyscallReturn gethostnameFunc(SyscallDesc *desc, int num,
167                              LiveProcess *p, ThreadContext *tc);
168
169/// Target getcwd() handler.
170SyscallReturn getcwdFunc(SyscallDesc *desc, int num,
171                         LiveProcess *p, ThreadContext *tc);
172
173/// Target readlink() handler.
174SyscallReturn readlinkFunc(SyscallDesc *desc, int num,
175                           LiveProcess *p, ThreadContext *tc,
176                           int index = 0);
177SyscallReturn readlinkFunc(SyscallDesc *desc, int num,
178                           LiveProcess *p, ThreadContext *tc);
179
180/// Target unlink() handler.
181SyscallReturn unlinkHelper(SyscallDesc *desc, int num,
182                           LiveProcess *p, ThreadContext *tc,
183                           int index);
184SyscallReturn unlinkFunc(SyscallDesc *desc, int num,
185                         LiveProcess *p, ThreadContext *tc);
186
187/// Target mkdir() handler.
188SyscallReturn mkdirFunc(SyscallDesc *desc, int num,
189                        LiveProcess *p, ThreadContext *tc);
190
191/// Target rename() handler.
192SyscallReturn renameFunc(SyscallDesc *desc, int num,
193                         LiveProcess *p, ThreadContext *tc);
194
195
196/// Target truncate() handler.
197SyscallReturn truncateFunc(SyscallDesc *desc, int num,
198                           LiveProcess *p, ThreadContext *tc);
199
200
201/// Target ftruncate() handler.
202SyscallReturn ftruncateFunc(SyscallDesc *desc, int num,
203                            LiveProcess *p, ThreadContext *tc);
204
205
206/// Target truncate64() handler.
207SyscallReturn truncate64Func(SyscallDesc *desc, int num,
208                             LiveProcess *p, ThreadContext *tc);
209
210/// Target ftruncate64() handler.
211SyscallReturn ftruncate64Func(SyscallDesc *desc, int num,
212                              LiveProcess *p, ThreadContext *tc);
213
214
215/// Target umask() handler.
216SyscallReturn umaskFunc(SyscallDesc *desc, int num,
217                        LiveProcess *p, ThreadContext *tc);
218
219
220/// Target chown() handler.
221SyscallReturn chownFunc(SyscallDesc *desc, int num,
222                        LiveProcess *p, ThreadContext *tc);
223
224
225/// Target fchown() handler.
226SyscallReturn fchownFunc(SyscallDesc *desc, int num,
227                         LiveProcess *p, ThreadContext *tc);
228
229/// Target dup() handler.
230SyscallReturn dupFunc(SyscallDesc *desc, int num,
231                      LiveProcess *process, ThreadContext *tc);
232
233/// Target fnctl() handler.
234SyscallReturn fcntlFunc(SyscallDesc *desc, int num,
235                        LiveProcess *process, ThreadContext *tc);
236
237/// Target fcntl64() handler.
238SyscallReturn fcntl64Func(SyscallDesc *desc, int num,
239                        LiveProcess *process, ThreadContext *tc);
240
241/// Target setuid() handler.
242SyscallReturn setuidFunc(SyscallDesc *desc, int num,
243                               LiveProcess *p, ThreadContext *tc);
244
245/// Target getpid() handler.
246SyscallReturn getpidFunc(SyscallDesc *desc, int num,
247                               LiveProcess *p, ThreadContext *tc);
248
249/// Target getuid() handler.
250SyscallReturn getuidFunc(SyscallDesc *desc, int num,
251                               LiveProcess *p, ThreadContext *tc);
252
253/// Target getgid() handler.
254SyscallReturn getgidFunc(SyscallDesc *desc, int num,
255                               LiveProcess *p, ThreadContext *tc);
256
257/// Target getppid() handler.
258SyscallReturn getppidFunc(SyscallDesc *desc, int num,
259                               LiveProcess *p, ThreadContext *tc);
260
261/// Target geteuid() handler.
262SyscallReturn geteuidFunc(SyscallDesc *desc, int num,
263                               LiveProcess *p, ThreadContext *tc);
264
265/// Target getegid() handler.
266SyscallReturn getegidFunc(SyscallDesc *desc, int num,
267                               LiveProcess *p, ThreadContext *tc);
268
269/// Target clone() handler.
270SyscallReturn cloneFunc(SyscallDesc *desc, int num,
271                               LiveProcess *p, ThreadContext *tc);
272
273/// Target access() handler
274SyscallReturn accessFunc(SyscallDesc *desc, int num,
275                               LiveProcess *p, ThreadContext *tc);
276SyscallReturn accessFunc(SyscallDesc *desc, int num,
277                               LiveProcess *p, ThreadContext *tc,
278                               int index);
279
280/// Futex system call
281///  Implemented by Daniel Sanchez
282///  Used by printf's in multi-threaded apps
283template <class OS>
284SyscallReturn
285futexFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
286          ThreadContext *tc)
287{
288    int index_uaddr = 0;
289    int index_op = 1;
290    int index_val = 2;
291    int index_timeout = 3;
292
293    uint64_t uaddr = process->getSyscallArg(tc, index_uaddr);
294    int op = process->getSyscallArg(tc, index_op);
295    int val = process->getSyscallArg(tc, index_val);
296    uint64_t timeout = process->getSyscallArg(tc, index_timeout);
297
298    std::map<uint64_t, std::list<ThreadContext *> * >
299        &futex_map = tc->getSystemPtr()->futexMap;
300
301    DPRINTF(SyscallVerbose, "In sys_futex: Address=%llx, op=%d, val=%d\n",
302            uaddr, op, val);
303
304    op &= ~OS::TGT_FUTEX_PRIVATE_FLAG;
305
306    if (op == OS::TGT_FUTEX_WAIT) {
307        if (timeout != 0) {
308            warn("sys_futex: FUTEX_WAIT with non-null timeout unimplemented;"
309                 "we'll wait indefinitely");
310        }
311
312        uint8_t *buf = new uint8_t[sizeof(int)];
313        tc->getMemProxy().readBlob((Addr)uaddr, buf, (int)sizeof(int));
314        int mem_val = *((int *)buf);
315        delete[] buf;
316
317        if (val != mem_val) {
318            DPRINTF(SyscallVerbose, "sys_futex: FUTEX_WAKE, read: %d, "
319                                    "expected: %d\n", mem_val, val);
320            return -OS::TGT_EWOULDBLOCK;
321        }
322
323        // Queue the thread context
324        std::list<ThreadContext *> * tcWaitList;
325        if (futex_map.count(uaddr)) {
326            tcWaitList = futex_map.find(uaddr)->second;
327        } else {
328            tcWaitList = new std::list<ThreadContext *>();
329            futex_map.insert(std::pair< uint64_t,
330                            std::list<ThreadContext *> * >(uaddr, tcWaitList));
331        }
332        tcWaitList->push_back(tc);
333        DPRINTF(SyscallVerbose, "sys_futex: FUTEX_WAIT, suspending calling "
334                                "thread context\n");
335        tc->suspend();
336        return 0;
337    } else if (op == OS::TGT_FUTEX_WAKE){
338        int wokenUp = 0;
339        std::list<ThreadContext *> * tcWaitList;
340        if (futex_map.count(uaddr)) {
341            tcWaitList = futex_map.find(uaddr)->second;
342            while (tcWaitList->size() > 0 && wokenUp < val) {
343                tcWaitList->front()->activate();
344                tcWaitList->pop_front();
345                wokenUp++;
346            }
347            if (tcWaitList->empty()) {
348                futex_map.erase(uaddr);
349                delete tcWaitList;
350            }
351        }
352        DPRINTF(SyscallVerbose, "sys_futex: FUTEX_WAKE, activated %d waiting "
353                                "thread contexts\n", wokenUp);
354        return wokenUp;
355    } else {
356        warn("sys_futex: op %d is not implemented, just returning...", op);
357        return 0;
358    }
359
360}
361
362
363/// Pseudo Funcs  - These functions use a different return convension,
364/// returning a second value in a register other than the normal return register
365SyscallReturn pipePseudoFunc(SyscallDesc *desc, int num,
366                             LiveProcess *process, ThreadContext *tc);
367
368/// Target getpidPseudo() handler.
369SyscallReturn getpidPseudoFunc(SyscallDesc *desc, int num,
370                               LiveProcess *p, ThreadContext *tc);
371
372/// Target getuidPseudo() handler.
373SyscallReturn getuidPseudoFunc(SyscallDesc *desc, int num,
374                               LiveProcess *p, ThreadContext *tc);
375
376/// Target getgidPseudo() handler.
377SyscallReturn getgidPseudoFunc(SyscallDesc *desc, int num,
378                               LiveProcess *p, ThreadContext *tc);
379
380
381/// A readable name for 1,000,000, for converting microseconds to seconds.
382const int one_million = 1000000;
383/// A readable name for 1,000,000,000, for converting nanoseconds to seconds.
384const int one_billion = 1000000000;
385
386/// Approximate seconds since the epoch (1/1/1970).  About a billion,
387/// by my reckoning.  We want to keep this a constant (not use the
388/// real-world time) to keep simulations repeatable.
389const unsigned seconds_since_epoch = 1000000000;
390
391/// Helper function to convert current elapsed time to seconds and
392/// microseconds.
393template <class T1, class T2>
394void
395getElapsedTimeMicro(T1 &sec, T2 &usec)
396{
397    uint64_t elapsed_usecs = curTick() / SimClock::Int::us;
398    sec = elapsed_usecs / one_million;
399    usec = elapsed_usecs % one_million;
400}
401
402/// Helper function to convert current elapsed time to seconds and
403/// nanoseconds.
404template <class T1, class T2>
405void
406getElapsedTimeNano(T1 &sec, T2 &nsec)
407{
408    uint64_t elapsed_nsecs = curTick() / SimClock::Int::ns;
409    sec = elapsed_nsecs / one_billion;
410    nsec = elapsed_nsecs % one_billion;
411}
412
413//////////////////////////////////////////////////////////////////////
414//
415// The following emulation functions are generic, but need to be
416// templated to account for differences in types, constants, etc.
417//
418//////////////////////////////////////////////////////////////////////
419
420    typedef struct statfs hst_statfs;
421#if NO_STAT64
422    typedef struct stat hst_stat;
423    typedef struct stat hst_stat64;
424#else
425    typedef struct stat hst_stat;
426    typedef struct stat64 hst_stat64;
427#endif
428
429//// Helper function to convert a host stat buffer to a target stat
430//// buffer.  Also copies the target buffer out to the simulated
431//// memory space.  Used by stat(), fstat(), and lstat().
432
433template <typename target_stat, typename host_stat>
434static void
435convertStatBuf(target_stat &tgt, host_stat *host, bool fakeTTY = false)
436{
437    using namespace TheISA;
438
439    if (fakeTTY)
440        tgt->st_dev = 0xA;
441    else
442        tgt->st_dev = host->st_dev;
443    tgt->st_dev = TheISA::htog(tgt->st_dev);
444    tgt->st_ino = host->st_ino;
445    tgt->st_ino = TheISA::htog(tgt->st_ino);
446    tgt->st_mode = host->st_mode;
447    if (fakeTTY) {
448        // Claim to be a character device
449        tgt->st_mode &= ~S_IFMT;    // Clear S_IFMT
450        tgt->st_mode |= S_IFCHR;    // Set S_IFCHR
451    }
452    tgt->st_mode = TheISA::htog(tgt->st_mode);
453    tgt->st_nlink = host->st_nlink;
454    tgt->st_nlink = TheISA::htog(tgt->st_nlink);
455    tgt->st_uid = host->st_uid;
456    tgt->st_uid = TheISA::htog(tgt->st_uid);
457    tgt->st_gid = host->st_gid;
458    tgt->st_gid = TheISA::htog(tgt->st_gid);
459    if (fakeTTY)
460        tgt->st_rdev = 0x880d;
461    else
462        tgt->st_rdev = host->st_rdev;
463    tgt->st_rdev = TheISA::htog(tgt->st_rdev);
464    tgt->st_size = host->st_size;
465    tgt->st_size = TheISA::htog(tgt->st_size);
466    tgt->st_atimeX = host->st_atime;
467    tgt->st_atimeX = TheISA::htog(tgt->st_atimeX);
468    tgt->st_mtimeX = host->st_mtime;
469    tgt->st_mtimeX = TheISA::htog(tgt->st_mtimeX);
470    tgt->st_ctimeX = host->st_ctime;
471    tgt->st_ctimeX = TheISA::htog(tgt->st_ctimeX);
472    // Force the block size to be 8k. This helps to ensure buffered io works
473    // consistently across different hosts.
474    tgt->st_blksize = 0x2000;
475    tgt->st_blksize = TheISA::htog(tgt->st_blksize);
476    tgt->st_blocks = host->st_blocks;
477    tgt->st_blocks = TheISA::htog(tgt->st_blocks);
478}
479
480// Same for stat64
481
482template <typename target_stat, typename host_stat64>
483static void
484convertStat64Buf(target_stat &tgt, host_stat64 *host, bool fakeTTY = false)
485{
486    using namespace TheISA;
487
488    convertStatBuf<target_stat, host_stat64>(tgt, host, fakeTTY);
489#if defined(STAT_HAVE_NSEC)
490    tgt->st_atime_nsec = host->st_atime_nsec;
491    tgt->st_atime_nsec = TheISA::htog(tgt->st_atime_nsec);
492    tgt->st_mtime_nsec = host->st_mtime_nsec;
493    tgt->st_mtime_nsec = TheISA::htog(tgt->st_mtime_nsec);
494    tgt->st_ctime_nsec = host->st_ctime_nsec;
495    tgt->st_ctime_nsec = TheISA::htog(tgt->st_ctime_nsec);
496#else
497    tgt->st_atime_nsec = 0;
498    tgt->st_mtime_nsec = 0;
499    tgt->st_ctime_nsec = 0;
500#endif
501}
502
503//Here are a couple convenience functions
504template<class OS>
505static void
506copyOutStatBuf(SETranslatingPortProxy &mem, Addr addr,
507        hst_stat *host, bool fakeTTY = false)
508{
509    typedef TypedBufferArg<typename OS::tgt_stat> tgt_stat_buf;
510    tgt_stat_buf tgt(addr);
511    convertStatBuf<tgt_stat_buf, hst_stat>(tgt, host, fakeTTY);
512    tgt.copyOut(mem);
513}
514
515template<class OS>
516static void
517copyOutStat64Buf(SETranslatingPortProxy &mem, Addr addr,
518        hst_stat64 *host, bool fakeTTY = false)
519{
520    typedef TypedBufferArg<typename OS::tgt_stat64> tgt_stat_buf;
521    tgt_stat_buf tgt(addr);
522    convertStat64Buf<tgt_stat_buf, hst_stat64>(tgt, host, fakeTTY);
523    tgt.copyOut(mem);
524}
525
526template <class OS>
527static void
528copyOutStatfsBuf(SETranslatingPortProxy &mem, Addr addr,
529                 hst_statfs *host)
530{
531    TypedBufferArg<typename OS::tgt_statfs> tgt(addr);
532
533#if defined(__OpenBSD__) || defined(__APPLE__) || defined(__FreeBSD__)
534    tgt->f_type = 0;
535#else
536    tgt->f_type = TheISA::htog(host->f_type);
537#endif
538    tgt->f_bsize = TheISA::htog(host->f_bsize);
539    tgt->f_blocks = TheISA::htog(host->f_blocks);
540    tgt->f_bfree = TheISA::htog(host->f_bfree);
541    tgt->f_bavail = TheISA::htog(host->f_bavail);
542    tgt->f_files = TheISA::htog(host->f_files);
543    tgt->f_ffree = TheISA::htog(host->f_ffree);
544    memcpy(&tgt->f_fsid, &host->f_fsid, sizeof(host->f_fsid));
545    tgt->f_namelen = TheISA::htog(host->f_namelen);
546    tgt->f_frsize = TheISA::htog(host->f_frsize);
547    memcpy(&tgt->f_spare, &host->f_spare, sizeof(host->f_spare));
548
549    tgt.copyOut(mem);
550}
551
552/// Target ioctl() handler.  For the most part, programs call ioctl()
553/// only to find out if their stdout is a tty, to determine whether to
554/// do line or block buffering.  We always claim that output fds are
555/// not TTYs to provide repeatable results.
556template <class OS>
557SyscallReturn
558ioctlFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
559          ThreadContext *tc)
560{
561    int index = 0;
562    int tgt_fd = process->getSyscallArg(tc, index);
563    unsigned req = process->getSyscallArg(tc, index);
564
565    DPRINTF(SyscallVerbose, "ioctl(%d, 0x%x, ...)\n", tgt_fd, req);
566
567    FDEntry *fde = process->getFDEntry(tgt_fd);
568
569    if (fde == NULL) {
570        // doesn't map to any simulator fd: not a valid target fd
571        return -EBADF;
572    }
573
574    if (fde->driver != NULL) {
575        return fde->driver->ioctl(process, tc, req);
576    }
577
578    if (OS::isTtyReq(req)) {
579        return -ENOTTY;
580    }
581
582    warn("Unsupported ioctl call: ioctl(%d, 0x%x, ...) @ \n",
583         tgt_fd, req, tc->pcState());
584    return -ENOTTY;
585}
586
587template <class OS>
588static SyscallReturn
589openFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
590         ThreadContext *tc, int index)
591{
592    std::string path;
593
594    if (!tc->getMemProxy().tryReadString(path,
595                process->getSyscallArg(tc, index)))
596        return -EFAULT;
597
598    int tgtFlags = process->getSyscallArg(tc, index);
599    int mode = process->getSyscallArg(tc, index);
600    int hostFlags = 0;
601
602    // translate open flags
603    for (int i = 0; i < OS::NUM_OPEN_FLAGS; i++) {
604        if (tgtFlags & OS::openFlagTable[i].tgtFlag) {
605            tgtFlags &= ~OS::openFlagTable[i].tgtFlag;
606            hostFlags |= OS::openFlagTable[i].hostFlag;
607        }
608    }
609
610    // any target flags left?
611    if (tgtFlags != 0)
612        warn("Syscall: open: cannot decode flags 0x%x", tgtFlags);
613
614#ifdef __CYGWIN32__
615    hostFlags |= O_BINARY;
616#endif
617
618    // Adjust path for current working directory
619    path = process->fullPath(path);
620
621    DPRINTF(SyscallVerbose, "opening file %s\n", path.c_str());
622
623    if (startswith(path, "/dev/")) {
624        std::string filename = path.substr(strlen("/dev/"));
625        if (filename == "sysdev0") {
626            // This is a memory-mapped high-resolution timer device on Alpha.
627            // We don't support it, so just punt.
628            warn("Ignoring open(%s, ...)\n", path);
629            return -ENOENT;
630        }
631
632        EmulatedDriver *drv = process->findDriver(filename);
633        if (drv != NULL) {
634            // the driver's open method will allocate a fd from the
635            // process if necessary.
636            return drv->open(process, tc, mode, hostFlags);
637        }
638
639        // fall through here for pass through to host devices, such as
640        // /dev/zero
641    }
642
643    int fd;
644    int local_errno;
645    if (startswith(path, "/proc/") || startswith(path, "/system/") ||
646        startswith(path, "/platform/") || startswith(path, "/sys/")) {
647        // It's a proc/sys entry and requires special handling
648        fd = OS::openSpecialFile(path, process, tc);
649        local_errno = ENOENT;
650     } else {
651        // open the file
652        fd = open(path.c_str(), hostFlags, mode);
653        local_errno = errno;
654     }
655
656    if (fd == -1)
657        return -local_errno;
658
659    return process->allocFD(fd, path.c_str(), hostFlags, mode, false);
660}
661
662/// Target open() handler.
663template <class OS>
664SyscallReturn
665openFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
666         ThreadContext *tc)
667{
668    return openFunc<OS>(desc, callnum, process, tc, 0);
669}
670
671/// Target openat() handler.
672template <class OS>
673SyscallReturn
674openatFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
675         ThreadContext *tc)
676{
677    int index = 0;
678    int dirfd = process->getSyscallArg(tc, index);
679    if (dirfd != OS::TGT_AT_FDCWD)
680        warn("openat: first argument not AT_FDCWD; unlikely to work");
681    return openFunc<OS>(desc, callnum, process, tc, 1);
682}
683
684/// Target unlinkat() handler.
685template <class OS>
686SyscallReturn
687unlinkatFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
688             ThreadContext *tc)
689{
690    int index = 0;
691    int dirfd = process->getSyscallArg(tc, index);
692    if (dirfd != OS::TGT_AT_FDCWD)
693        warn("unlinkat: first argument not AT_FDCWD; unlikely to work");
694
695    return unlinkHelper(desc, callnum, process, tc, 1);
696}
697
698/// Target facessat() handler
699template <class OS>
700SyscallReturn
701faccessatFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
702        ThreadContext *tc)
703{
704    int index = 0;
705    int dirfd = process->getSyscallArg(tc, index);
706    if (dirfd != OS::TGT_AT_FDCWD)
707        warn("faccessat: first argument not AT_FDCWD; unlikely to work");
708    return accessFunc(desc, callnum, process, tc, 1);
709}
710
711/// Target readlinkat() handler
712template <class OS>
713SyscallReturn
714readlinkatFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
715        ThreadContext *tc)
716{
717    int index = 0;
718    int dirfd = process->getSyscallArg(tc, index);
719    if (dirfd != OS::TGT_AT_FDCWD)
720        warn("openat: first argument not AT_FDCWD; unlikely to work");
721    return readlinkFunc(desc, callnum, process, tc, 1);
722}
723
724/// Target renameat() handler.
725template <class OS>
726SyscallReturn
727renameatFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
728             ThreadContext *tc)
729{
730    int index = 0;
731
732    int olddirfd = process->getSyscallArg(tc, index);
733    if (olddirfd != OS::TGT_AT_FDCWD)
734        warn("renameat: first argument not AT_FDCWD; unlikely to work");
735
736    std::string old_name;
737
738    if (!tc->getMemProxy().tryReadString(old_name,
739                                         process->getSyscallArg(tc, index)))
740        return -EFAULT;
741
742    int newdirfd = process->getSyscallArg(tc, index);
743    if (newdirfd != OS::TGT_AT_FDCWD)
744        warn("renameat: third argument not AT_FDCWD; unlikely to work");
745
746    std::string new_name;
747
748    if (!tc->getMemProxy().tryReadString(new_name,
749                                         process->getSyscallArg(tc, index)))
750        return -EFAULT;
751
752    // Adjust path for current working directory
753    old_name = process->fullPath(old_name);
754    new_name = process->fullPath(new_name);
755
756    int result = rename(old_name.c_str(), new_name.c_str());
757    return (result == -1) ? -errno : result;
758}
759
760/// Target sysinfo() handler.
761template <class OS>
762SyscallReturn
763sysinfoFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
764         ThreadContext *tc)
765{
766
767    int index = 0;
768    TypedBufferArg<typename OS::tgt_sysinfo>
769        sysinfo(process->getSyscallArg(tc, index));
770
771    sysinfo->uptime = seconds_since_epoch;
772    sysinfo->totalram = process->system->memSize();
773    sysinfo->mem_unit = 1;
774
775    sysinfo.copyOut(tc->getMemProxy());
776
777    return 0;
778}
779
780/// Target chmod() handler.
781template <class OS>
782SyscallReturn
783chmodFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
784          ThreadContext *tc)
785{
786    std::string path;
787
788    int index = 0;
789    if (!tc->getMemProxy().tryReadString(path,
790                process->getSyscallArg(tc, index))) {
791        return -EFAULT;
792    }
793
794    uint32_t mode = process->getSyscallArg(tc, index);
795    mode_t hostMode = 0;
796
797    // XXX translate mode flags via OS::something???
798    hostMode = mode;
799
800    // Adjust path for current working directory
801    path = process->fullPath(path);
802
803    // do the chmod
804    int result = chmod(path.c_str(), hostMode);
805    if (result < 0)
806        return -errno;
807
808    return 0;
809}
810
811
812/// Target fchmod() handler.
813template <class OS>
814SyscallReturn
815fchmodFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
816           ThreadContext *tc)
817{
818    int index = 0;
819    int tgt_fd = process->getSyscallArg(tc, index);
820    uint32_t mode = process->getSyscallArg(tc, index);
821
822    int sim_fd = process->getSimFD(tgt_fd);
823    if (sim_fd < 0)
824        return -EBADF;
825
826    mode_t hostMode = 0;
827
828    // XXX translate mode flags via OS::someting???
829    hostMode = mode;
830
831    // do the fchmod
832    int result = fchmod(sim_fd, hostMode);
833    if (result < 0)
834        return -errno;
835
836    return 0;
837}
838
839/// Target mremap() handler.
840template <class OS>
841SyscallReturn
842mremapFunc(SyscallDesc *desc, int callnum, LiveProcess *process, ThreadContext *tc)
843{
844    int index = 0;
845    Addr start = process->getSyscallArg(tc, index);
846    uint64_t old_length = process->getSyscallArg(tc, index);
847    uint64_t new_length = process->getSyscallArg(tc, index);
848    uint64_t flags = process->getSyscallArg(tc, index);
849    uint64_t provided_address = 0;
850    bool use_provided_address = flags & OS::TGT_MREMAP_FIXED;
851
852    if (use_provided_address)
853        provided_address = process->getSyscallArg(tc, index);
854
855    if ((start % TheISA::PageBytes != 0) ||
856        (provided_address % TheISA::PageBytes != 0)) {
857        warn("mremap failing: arguments not page aligned");
858        return -EINVAL;
859    }
860
861    new_length = roundUp(new_length, TheISA::PageBytes);
862
863    if (new_length > old_length) {
864        if ((start + old_length) == process->mmap_end &&
865            (!use_provided_address || provided_address == start)) {
866            uint64_t diff = new_length - old_length;
867            process->allocateMem(process->mmap_end, diff);
868            process->mmap_end += diff;
869            return start;
870        } else {
871            if (!use_provided_address && !(flags & OS::TGT_MREMAP_MAYMOVE)) {
872                warn("can't remap here and MREMAP_MAYMOVE flag not set\n");
873                return -ENOMEM;
874            } else {
875                uint64_t new_start = use_provided_address ?
876                    provided_address : process->mmap_end;
877                process->pTable->remap(start, old_length, new_start);
878                warn("mremapping to new vaddr %08p-%08p, adding %d\n",
879                     new_start, new_start + new_length,
880                     new_length - old_length);
881                // add on the remaining unallocated pages
882                process->allocateMem(new_start + old_length,
883                                     new_length - old_length,
884                                     use_provided_address /* clobber */);
885                if (!use_provided_address)
886                    process->mmap_end += new_length;
887                if (use_provided_address &&
888                    new_start + new_length > process->mmap_end) {
889                    // something fishy going on here, at least notify the user
890                    // @todo: increase mmap_end?
891                    warn("mmap region limit exceeded with MREMAP_FIXED\n");
892                }
893                warn("returning %08p as start\n", new_start);
894                return new_start;
895            }
896        }
897    } else {
898        if (use_provided_address && provided_address != start)
899            process->pTable->remap(start, new_length, provided_address);
900        process->pTable->unmap(start + new_length, old_length - new_length);
901        return use_provided_address ? provided_address : start;
902    }
903}
904
905/// Target stat() handler.
906template <class OS>
907SyscallReturn
908statFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
909         ThreadContext *tc)
910{
911    std::string path;
912
913    int index = 0;
914    if (!tc->getMemProxy().tryReadString(path,
915                process->getSyscallArg(tc, index))) {
916        return -EFAULT;
917    }
918    Addr bufPtr = process->getSyscallArg(tc, index);
919
920    // Adjust path for current working directory
921    path = process->fullPath(path);
922
923    struct stat hostBuf;
924    int result = stat(path.c_str(), &hostBuf);
925
926    if (result < 0)
927        return -errno;
928
929    copyOutStatBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
930
931    return 0;
932}
933
934
935/// Target stat64() handler.
936template <class OS>
937SyscallReturn
938stat64Func(SyscallDesc *desc, int callnum, LiveProcess *process,
939           ThreadContext *tc)
940{
941    std::string path;
942
943    int index = 0;
944    if (!tc->getMemProxy().tryReadString(path,
945                process->getSyscallArg(tc, index)))
946        return -EFAULT;
947    Addr bufPtr = process->getSyscallArg(tc, index);
948
949    // Adjust path for current working directory
950    path = process->fullPath(path);
951
952#if NO_STAT64
953    struct stat  hostBuf;
954    int result = stat(path.c_str(), &hostBuf);
955#else
956    struct stat64 hostBuf;
957    int result = stat64(path.c_str(), &hostBuf);
958#endif
959
960    if (result < 0)
961        return -errno;
962
963    copyOutStat64Buf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
964
965    return 0;
966}
967
968
969/// Target fstatat64() handler.
970template <class OS>
971SyscallReturn
972fstatat64Func(SyscallDesc *desc, int callnum, LiveProcess *process,
973              ThreadContext *tc)
974{
975    int index = 0;
976    int dirfd = process->getSyscallArg(tc, index);
977    if (dirfd != OS::TGT_AT_FDCWD)
978        warn("fstatat64: first argument not AT_FDCWD; unlikely to work");
979
980    std::string path;
981    if (!tc->getMemProxy().tryReadString(path,
982                process->getSyscallArg(tc, index)))
983        return -EFAULT;
984    Addr bufPtr = process->getSyscallArg(tc, index);
985
986    // Adjust path for current working directory
987    path = process->fullPath(path);
988
989#if NO_STAT64
990    struct stat  hostBuf;
991    int result = stat(path.c_str(), &hostBuf);
992#else
993    struct stat64 hostBuf;
994    int result = stat64(path.c_str(), &hostBuf);
995#endif
996
997    if (result < 0)
998        return -errno;
999
1000    copyOutStat64Buf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
1001
1002    return 0;
1003}
1004
1005
1006/// Target fstat64() handler.
1007template <class OS>
1008SyscallReturn
1009fstat64Func(SyscallDesc *desc, int callnum, LiveProcess *process,
1010            ThreadContext *tc)
1011{
1012    int index = 0;
1013    int tgt_fd = process->getSyscallArg(tc, index);
1014    Addr bufPtr = process->getSyscallArg(tc, index);
1015
1016    int sim_fd = process->getSimFD(tgt_fd);
1017    if (sim_fd < 0)
1018        return -EBADF;
1019
1020#if NO_STAT64
1021    struct stat  hostBuf;
1022    int result = fstat(sim_fd, &hostBuf);
1023#else
1024    struct stat64  hostBuf;
1025    int result = fstat64(sim_fd, &hostBuf);
1026#endif
1027
1028    if (result < 0)
1029        return -errno;
1030
1031    copyOutStat64Buf<OS>(tc->getMemProxy(), bufPtr, &hostBuf, (sim_fd == 1));
1032
1033    return 0;
1034}
1035
1036
1037/// Target lstat() handler.
1038template <class OS>
1039SyscallReturn
1040lstatFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1041          ThreadContext *tc)
1042{
1043    std::string path;
1044
1045    int index = 0;
1046    if (!tc->getMemProxy().tryReadString(path,
1047                process->getSyscallArg(tc, index))) {
1048        return -EFAULT;
1049    }
1050    Addr bufPtr = process->getSyscallArg(tc, index);
1051
1052    // Adjust path for current working directory
1053    path = process->fullPath(path);
1054
1055    struct stat hostBuf;
1056    int result = lstat(path.c_str(), &hostBuf);
1057
1058    if (result < 0)
1059        return -errno;
1060
1061    copyOutStatBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
1062
1063    return 0;
1064}
1065
1066/// Target lstat64() handler.
1067template <class OS>
1068SyscallReturn
1069lstat64Func(SyscallDesc *desc, int callnum, LiveProcess *process,
1070            ThreadContext *tc)
1071{
1072    std::string path;
1073
1074    int index = 0;
1075    if (!tc->getMemProxy().tryReadString(path,
1076                process->getSyscallArg(tc, index))) {
1077        return -EFAULT;
1078    }
1079    Addr bufPtr = process->getSyscallArg(tc, index);
1080
1081    // Adjust path for current working directory
1082    path = process->fullPath(path);
1083
1084#if NO_STAT64
1085    struct stat hostBuf;
1086    int result = lstat(path.c_str(), &hostBuf);
1087#else
1088    struct stat64 hostBuf;
1089    int result = lstat64(path.c_str(), &hostBuf);
1090#endif
1091
1092    if (result < 0)
1093        return -errno;
1094
1095    copyOutStat64Buf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
1096
1097    return 0;
1098}
1099
1100/// Target fstat() handler.
1101template <class OS>
1102SyscallReturn
1103fstatFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1104          ThreadContext *tc)
1105{
1106    int index = 0;
1107    int tgt_fd = process->getSyscallArg(tc, index);
1108    Addr bufPtr = process->getSyscallArg(tc, index);
1109
1110    DPRINTF_SYSCALL(Verbose, "fstat(%d, ...)\n", tgt_fd);
1111
1112    int sim_fd = process->getSimFD(tgt_fd);
1113    if (sim_fd < 0)
1114        return -EBADF;
1115
1116    struct stat hostBuf;
1117    int result = fstat(sim_fd, &hostBuf);
1118
1119    if (result < 0)
1120        return -errno;
1121
1122    copyOutStatBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf, (sim_fd == 1));
1123
1124    return 0;
1125}
1126
1127
1128/// Target statfs() handler.
1129template <class OS>
1130SyscallReturn
1131statfsFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1132           ThreadContext *tc)
1133{
1134#if NO_STATFS
1135    warn("Host OS cannot support calls to statfs. Ignoring syscall");
1136#else
1137    std::string path;
1138
1139    int index = 0;
1140    if (!tc->getMemProxy().tryReadString(path,
1141                process->getSyscallArg(tc, index))) {
1142        return -EFAULT;
1143    }
1144    Addr bufPtr = process->getSyscallArg(tc, index);
1145
1146    // Adjust path for current working directory
1147    path = process->fullPath(path);
1148
1149    struct statfs hostBuf;
1150    int result = statfs(path.c_str(), &hostBuf);
1151
1152    if (result < 0)
1153        return -errno;
1154
1155    copyOutStatfsBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
1156#endif
1157    return 0;
1158}
1159
1160
1161/// Target fstatfs() handler.
1162template <class OS>
1163SyscallReturn
1164fstatfsFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1165            ThreadContext *tc)
1166{
1167    int index = 0;
1168    int tgt_fd = process->getSyscallArg(tc, index);
1169    Addr bufPtr = process->getSyscallArg(tc, index);
1170
1171    int sim_fd = process->getSimFD(tgt_fd);
1172    if (sim_fd < 0)
1173        return -EBADF;
1174
1175    struct statfs hostBuf;
1176    int result = fstatfs(sim_fd, &hostBuf);
1177
1178    if (result < 0)
1179        return -errno;
1180
1181    copyOutStatfsBuf<OS>(tc->getMemProxy(), bufPtr, &hostBuf);
1182
1183    return 0;
1184}
1185
1186
1187/// Target writev() handler.
1188template <class OS>
1189SyscallReturn
1190writevFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1191           ThreadContext *tc)
1192{
1193    int index = 0;
1194    int tgt_fd = process->getSyscallArg(tc, index);
1195
1196    int sim_fd = process->getSimFD(tgt_fd);
1197    if (sim_fd < 0)
1198        return -EBADF;
1199
1200    SETranslatingPortProxy &p = tc->getMemProxy();
1201    uint64_t tiov_base = process->getSyscallArg(tc, index);
1202    size_t count = process->getSyscallArg(tc, index);
1203    struct iovec hiov[count];
1204    for (size_t i = 0; i < count; ++i) {
1205        typename OS::tgt_iovec tiov;
1206
1207        p.readBlob(tiov_base + i*sizeof(typename OS::tgt_iovec),
1208                   (uint8_t*)&tiov, sizeof(typename OS::tgt_iovec));
1209        hiov[i].iov_len = TheISA::gtoh(tiov.iov_len);
1210        hiov[i].iov_base = new char [hiov[i].iov_len];
1211        p.readBlob(TheISA::gtoh(tiov.iov_base), (uint8_t *)hiov[i].iov_base,
1212                   hiov[i].iov_len);
1213    }
1214
1215    int result = writev(sim_fd, hiov, count);
1216
1217    for (size_t i = 0; i < count; ++i)
1218        delete [] (char *)hiov[i].iov_base;
1219
1220    if (result < 0)
1221        return -errno;
1222
1223    return result;
1224}
1225
1226/// Real mmap handler.
1227template <class OS>
1228SyscallReturn
1229mmapImpl(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc,
1230         bool is_mmap2)
1231{
1232    int index = 0;
1233    Addr start = p->getSyscallArg(tc, index);
1234    uint64_t length = p->getSyscallArg(tc, index);
1235    int prot = p->getSyscallArg(tc, index);
1236    int tgt_flags = p->getSyscallArg(tc, index);
1237    int tgt_fd = p->getSyscallArg(tc, index);
1238    int offset = p->getSyscallArg(tc, index);
1239
1240    if (is_mmap2)
1241        offset *= TheISA::PageBytes;
1242
1243    if (start & (TheISA::PageBytes - 1) ||
1244        offset & (TheISA::PageBytes - 1) ||
1245        (tgt_flags & OS::TGT_MAP_PRIVATE &&
1246         tgt_flags & OS::TGT_MAP_SHARED) ||
1247        (!(tgt_flags & OS::TGT_MAP_PRIVATE) &&
1248         !(tgt_flags & OS::TGT_MAP_SHARED)) ||
1249        !length) {
1250        return -EINVAL;
1251    }
1252
1253    if ((prot & PROT_WRITE) && (tgt_flags & OS::TGT_MAP_SHARED)) {
1254        // With shared mmaps, there are two cases to consider:
1255        // 1) anonymous: writes should modify the mapping and this should be
1256        // visible to observers who share the mapping. Currently, it's
1257        // difficult to update the shared mapping because there's no
1258        // structure which maintains information about the which virtual
1259        // memory areas are shared. If that structure existed, it would be
1260        // possible to make the translations point to the same frames.
1261        // 2) file-backed: writes should modify the mapping and the file
1262        // which is backed by the mapping. The shared mapping problem is the
1263        // same as what was mentioned about the anonymous mappings. For
1264        // file-backed mappings, the writes to the file are difficult
1265        // because it requires syncing what the mapping holds with the file
1266        // that resides on the host system. So, any write on a real system
1267        // would cause the change to be propagated to the file mapping at
1268        // some point in the future (the inode is tracked along with the
1269        // mapping). This isn't guaranteed to always happen, but it usually
1270        // works well enough. The guarantee is provided by the msync system
1271        // call. We could force the change through with shared mappings with
1272        // a call to msync, but that again would require more information
1273        // than we currently maintain.
1274        warn("mmap: writing to shared mmap region is currently "
1275             "unsupported. The write succeeds on the target, but it "
1276             "will not be propagated to the host or shared mappings");
1277    }
1278
1279    length = roundUp(length, TheISA::PageBytes);
1280
1281    int sim_fd = -1;
1282    uint8_t *pmap = nullptr;
1283    if (!(tgt_flags & OS::TGT_MAP_ANONYMOUS)) {
1284        // Check for EmulatedDriver mmap
1285        FDEntry *fde = p->getFDEntry(tgt_fd);
1286        if (fde == NULL)
1287            return -EBADF;
1288
1289        if (fde->driver != NULL) {
1290            return fde->driver->mmap(p, tc, start, length, prot,
1291                                     tgt_flags, tgt_fd, offset);
1292        }
1293        sim_fd = fde->fd;
1294
1295        if (sim_fd < 0)
1296            return -EBADF;
1297
1298        pmap = (decltype(pmap))mmap(NULL, length, PROT_READ, MAP_PRIVATE,
1299                                    sim_fd, offset);
1300
1301        if (pmap == (decltype(pmap))-1) {
1302            warn("mmap: failed to map file into host address space");
1303            return -errno;
1304        }
1305    }
1306
1307    // Extend global mmap region if necessary. Note that we ignore the
1308    // start address unless MAP_FIXED is specified.
1309    if (!(tgt_flags & OS::TGT_MAP_FIXED)) {
1310        start = p->mmapGrowsDown() ? p->mmap_end - length : p->mmap_end;
1311        p->mmap_end = p->mmapGrowsDown() ? start : p->mmap_end + length;
1312    }
1313
1314    DPRINTF_SYSCALL(Verbose, " mmap range is 0x%x - 0x%x\n",
1315                    start, start + length - 1);
1316
1317    // We only allow mappings to overwrite existing mappings if
1318    // TGT_MAP_FIXED is set. Otherwise it shouldn't be a problem
1319    // because we ignore the start hint if TGT_MAP_FIXED is not set.
1320    int clobber = tgt_flags & OS::TGT_MAP_FIXED;
1321    if (clobber) {
1322        for (auto tc : p->system->threadContexts) {
1323            // If we might be overwriting old mappings, we need to
1324            // invalidate potentially stale mappings out of the TLBs.
1325            tc->getDTBPtr()->flushAll();
1326            tc->getITBPtr()->flushAll();
1327        }
1328    }
1329
1330    // Allocate physical memory and map it in. If the page table is already
1331    // mapped and clobber is not set, the simulator will issue throw a
1332    // fatal and bail out of the simulation.
1333    p->allocateMem(start, length, clobber);
1334
1335    // Transfer content into target address space.
1336    SETranslatingPortProxy &tp = tc->getMemProxy();
1337    if (tgt_flags & OS::TGT_MAP_ANONYMOUS) {
1338        // In general, we should zero the mapped area for anonymous mappings,
1339        // with something like:
1340        //     tp.memsetBlob(start, 0, length);
1341        // However, given that we don't support sparse mappings, and
1342        // some applications can map a couple of gigabytes of space
1343        // (intending sparse usage), that can get painfully expensive.
1344        // Fortunately, since we don't properly implement munmap either,
1345        // there's no danger of remapping used memory, so for now all
1346        // newly mapped memory should already be zeroed so we can skip it.
1347    } else {
1348        // It is possible to mmap an area larger than a file, however
1349        // accessing unmapped portions the system triggers a "Bus error"
1350        // on the host. We must know when to stop copying the file from
1351        // the host into the target address space.
1352        struct stat file_stat;
1353        if (fstat(sim_fd, &file_stat) > 0)
1354            fatal("mmap: cannot stat file");
1355
1356        // Copy the portion of the file that is resident. This requires
1357        // checking both the mmap size and the filesize that we are
1358        // trying to mmap into this space; the mmap size also depends
1359        // on the specified offset into the file.
1360        uint64_t size = std::min((uint64_t)file_stat.st_size - offset,
1361                                 length);
1362        tp.writeBlob(start, pmap, size);
1363
1364        // Cleanup the mmap region before exiting this function.
1365        munmap(pmap, length);
1366
1367        // Maintain the symbol table for dynamic executables.
1368        // The loader will call mmap to map the images into its address
1369        // space and we intercept that here. We can verify that we are
1370        // executing inside the loader by checking the program counter value.
1371        // XXX: with multiprogrammed workloads or multi-node configurations,
1372        // this will not work since there is a single global symbol table.
1373        ObjectFile *interpreter = p->getInterpreter();
1374        if (interpreter) {
1375            Addr text_start = interpreter->textBase();
1376            Addr text_end = text_start + interpreter->textSize();
1377
1378            Addr pc = tc->pcState().pc();
1379
1380            if (pc >= text_start && pc < text_end) {
1381                FDEntry *fde = p->getFDEntry(tgt_fd);
1382
1383                ObjectFile *lib = createObjectFile(fde->filename);
1384
1385                if (lib) {
1386                    lib->loadAllSymbols(debugSymbolTable,
1387                                        lib->textBase(), start);
1388                }
1389            }
1390        }
1391
1392        // Note that we do not zero out the remainder of the mapping. This
1393        // is done by a real system, but it probably will not affect
1394        // execution (hopefully).
1395    }
1396
1397    return start;
1398}
1399
1400template <class OS>
1401SyscallReturn
1402pwrite64Func(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
1403{
1404    int index = 0;
1405    int tgt_fd = p->getSyscallArg(tc, index);
1406    Addr bufPtr = p->getSyscallArg(tc, index);
1407    int nbytes = p->getSyscallArg(tc, index);
1408    int offset = p->getSyscallArg(tc, index);
1409
1410    int sim_fd = p->getSimFD(tgt_fd);
1411    if (sim_fd < 0)
1412        return -EBADF;
1413
1414    BufferArg bufArg(bufPtr, nbytes);
1415    bufArg.copyIn(tc->getMemProxy());
1416
1417    int bytes_written = pwrite(sim_fd, bufArg.bufferPtr(), nbytes, offset);
1418
1419    return (bytes_written == -1) ? -errno : bytes_written;
1420}
1421
1422/// Target mmap() handler.
1423template <class OS>
1424SyscallReturn
1425mmapFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
1426{
1427    return mmapImpl<OS>(desc, num, p, tc, false);
1428}
1429
1430/// Target mmap2() handler.
1431template <class OS>
1432SyscallReturn
1433mmap2Func(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
1434{
1435    return mmapImpl<OS>(desc, num, p, tc, true);
1436}
1437
1438/// Target getrlimit() handler.
1439template <class OS>
1440SyscallReturn
1441getrlimitFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1442        ThreadContext *tc)
1443{
1444    int index = 0;
1445    unsigned resource = process->getSyscallArg(tc, index);
1446    TypedBufferArg<typename OS::rlimit> rlp(process->getSyscallArg(tc, index));
1447
1448    switch (resource) {
1449        case OS::TGT_RLIMIT_STACK:
1450            // max stack size in bytes: make up a number (8MB for now)
1451            rlp->rlim_cur = rlp->rlim_max = 8 * 1024 * 1024;
1452            rlp->rlim_cur = TheISA::htog(rlp->rlim_cur);
1453            rlp->rlim_max = TheISA::htog(rlp->rlim_max);
1454            break;
1455
1456        case OS::TGT_RLIMIT_DATA:
1457            // max data segment size in bytes: make up a number
1458            rlp->rlim_cur = rlp->rlim_max = 256 * 1024 * 1024;
1459            rlp->rlim_cur = TheISA::htog(rlp->rlim_cur);
1460            rlp->rlim_max = TheISA::htog(rlp->rlim_max);
1461            break;
1462
1463        default:
1464            warn("getrlimit: unimplemented resource %d", resource);
1465            return -EINVAL;
1466            break;
1467    }
1468
1469    rlp.copyOut(tc->getMemProxy());
1470    return 0;
1471}
1472
1473/// Target clock_gettime() function.
1474template <class OS>
1475SyscallReturn
1476clock_gettimeFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
1477{
1478    int index = 1;
1479    //int clk_id = p->getSyscallArg(tc, index);
1480    TypedBufferArg<typename OS::timespec> tp(p->getSyscallArg(tc, index));
1481
1482    getElapsedTimeNano(tp->tv_sec, tp->tv_nsec);
1483    tp->tv_sec += seconds_since_epoch;
1484    tp->tv_sec = TheISA::htog(tp->tv_sec);
1485    tp->tv_nsec = TheISA::htog(tp->tv_nsec);
1486
1487    tp.copyOut(tc->getMemProxy());
1488
1489    return 0;
1490}
1491
1492/// Target clock_getres() function.
1493template <class OS>
1494SyscallReturn
1495clock_getresFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
1496{
1497    int index = 1;
1498    TypedBufferArg<typename OS::timespec> tp(p->getSyscallArg(tc, index));
1499
1500    // Set resolution at ns, which is what clock_gettime() returns
1501    tp->tv_sec = 0;
1502    tp->tv_nsec = 1;
1503
1504    tp.copyOut(tc->getMemProxy());
1505
1506    return 0;
1507}
1508
1509/// Target gettimeofday() handler.
1510template <class OS>
1511SyscallReturn
1512gettimeofdayFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1513        ThreadContext *tc)
1514{
1515    int index = 0;
1516    TypedBufferArg<typename OS::timeval> tp(process->getSyscallArg(tc, index));
1517
1518    getElapsedTimeMicro(tp->tv_sec, tp->tv_usec);
1519    tp->tv_sec += seconds_since_epoch;
1520    tp->tv_sec = TheISA::htog(tp->tv_sec);
1521    tp->tv_usec = TheISA::htog(tp->tv_usec);
1522
1523    tp.copyOut(tc->getMemProxy());
1524
1525    return 0;
1526}
1527
1528
1529/// Target utimes() handler.
1530template <class OS>
1531SyscallReturn
1532utimesFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1533           ThreadContext *tc)
1534{
1535    std::string path;
1536
1537    int index = 0;
1538    if (!tc->getMemProxy().tryReadString(path,
1539                process->getSyscallArg(tc, index))) {
1540        return -EFAULT;
1541    }
1542
1543    TypedBufferArg<typename OS::timeval [2]>
1544        tp(process->getSyscallArg(tc, index));
1545    tp.copyIn(tc->getMemProxy());
1546
1547    struct timeval hostTimeval[2];
1548    for (int i = 0; i < 2; ++i)
1549    {
1550        hostTimeval[i].tv_sec = TheISA::gtoh((*tp)[i].tv_sec);
1551        hostTimeval[i].tv_usec = TheISA::gtoh((*tp)[i].tv_usec);
1552    }
1553
1554    // Adjust path for current working directory
1555    path = process->fullPath(path);
1556
1557    int result = utimes(path.c_str(), hostTimeval);
1558
1559    if (result < 0)
1560        return -errno;
1561
1562    return 0;
1563}
1564/// Target getrusage() function.
1565template <class OS>
1566SyscallReturn
1567getrusageFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1568              ThreadContext *tc)
1569{
1570    int index = 0;
1571    int who = process->getSyscallArg(tc, index); // THREAD, SELF, or CHILDREN
1572    TypedBufferArg<typename OS::rusage> rup(process->getSyscallArg(tc, index));
1573
1574    rup->ru_utime.tv_sec = 0;
1575    rup->ru_utime.tv_usec = 0;
1576    rup->ru_stime.tv_sec = 0;
1577    rup->ru_stime.tv_usec = 0;
1578    rup->ru_maxrss = 0;
1579    rup->ru_ixrss = 0;
1580    rup->ru_idrss = 0;
1581    rup->ru_isrss = 0;
1582    rup->ru_minflt = 0;
1583    rup->ru_majflt = 0;
1584    rup->ru_nswap = 0;
1585    rup->ru_inblock = 0;
1586    rup->ru_oublock = 0;
1587    rup->ru_msgsnd = 0;
1588    rup->ru_msgrcv = 0;
1589    rup->ru_nsignals = 0;
1590    rup->ru_nvcsw = 0;
1591    rup->ru_nivcsw = 0;
1592
1593    switch (who) {
1594      case OS::TGT_RUSAGE_SELF:
1595        getElapsedTimeMicro(rup->ru_utime.tv_sec, rup->ru_utime.tv_usec);
1596        rup->ru_utime.tv_sec = TheISA::htog(rup->ru_utime.tv_sec);
1597        rup->ru_utime.tv_usec = TheISA::htog(rup->ru_utime.tv_usec);
1598        break;
1599
1600      case OS::TGT_RUSAGE_CHILDREN:
1601        // do nothing.  We have no child processes, so they take no time.
1602        break;
1603
1604      default:
1605        // don't really handle THREAD or CHILDREN, but just warn and
1606        // plow ahead
1607        warn("getrusage() only supports RUSAGE_SELF.  Parameter %d ignored.",
1608             who);
1609    }
1610
1611    rup.copyOut(tc->getMemProxy());
1612
1613    return 0;
1614}
1615
1616/// Target times() function.
1617template <class OS>
1618SyscallReturn
1619timesFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1620           ThreadContext *tc)
1621{
1622    int index = 0;
1623    TypedBufferArg<typename OS::tms> bufp(process->getSyscallArg(tc, index));
1624
1625    // Fill in the time structure (in clocks)
1626    int64_t clocks = curTick() * OS::M5_SC_CLK_TCK / SimClock::Int::s;
1627    bufp->tms_utime = clocks;
1628    bufp->tms_stime = 0;
1629    bufp->tms_cutime = 0;
1630    bufp->tms_cstime = 0;
1631
1632    // Convert to host endianness
1633    bufp->tms_utime = TheISA::htog(bufp->tms_utime);
1634
1635    // Write back
1636    bufp.copyOut(tc->getMemProxy());
1637
1638    // Return clock ticks since system boot
1639    return clocks;
1640}
1641
1642/// Target time() function.
1643template <class OS>
1644SyscallReturn
1645timeFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
1646           ThreadContext *tc)
1647{
1648    typename OS::time_t sec, usec;
1649    getElapsedTimeMicro(sec, usec);
1650    sec += seconds_since_epoch;
1651
1652    int index = 0;
1653    Addr taddr = (Addr)process->getSyscallArg(tc, index);
1654    if (taddr != 0) {
1655        typename OS::time_t t = sec;
1656        t = TheISA::htog(t);
1657        SETranslatingPortProxy &p = tc->getMemProxy();
1658        p.writeBlob(taddr, (uint8_t*)&t, (int)sizeof(typename OS::time_t));
1659    }
1660    return sec;
1661}
1662
1663
1664#endif // __SIM_SYSCALL_EMUL_HH__
1665