1/*
2 * Copyright (c) 2003-2005 The Regents of The University of Michigan
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Authors: Steve Reinhardt
29 * Ali Saidi
30 */
31
32#include <fcntl.h>
33#include <unistd.h>
34
35#include <cstdio>
36#include <iostream>
37#include <string>
38
39#include "arch/utility.hh"
40#include "base/chunk_generator.hh"
41#include "base/trace.hh"
42#include "config/the_isa.hh"
43#include "cpu/base.hh"
44#include "cpu/thread_context.hh"
45#include "debug/SyscallVerbose.hh"
46#include "mem/page_table.hh"
47#include "sim/process.hh"
48#include "sim/sim_exit.hh"
49#include "sim/syscall_emul.hh"
50#include "sim/system.hh"
51
52using namespace std;
53using namespace TheISA;
54
55void
56SyscallDesc::doSyscall(int callnum, LiveProcess *process, ThreadContext *tc)
57{
58#if TRACING_ON
59 int index = 0;
60#endif
61 DPRINTFR(SyscallVerbose,
62 "%d: %s: syscall %s called w/arguments %d,%d,%d,%d\n",
63 curTick(), tc->getCpuPtr()->name(), name,
64 process->getSyscallArg(tc, index),
65 process->getSyscallArg(tc, index),
66 process->getSyscallArg(tc, index),
67 process->getSyscallArg(tc, index));
68
69 SyscallReturn retval = (*funcPtr)(this, callnum, process, tc);
70
71 DPRINTFR(SyscallVerbose, "%d: %s: syscall %s returns %d\n",
72 curTick(),tc->getCpuPtr()->name(), name, retval.value());
73
74 if (!(flags & SyscallDesc::SuppressReturnValue))
75 process->setSyscallReturn(tc, retval);
76}
77
78
79SyscallReturn
80unimplementedFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
81 ThreadContext *tc)
82{
83 fatal("syscall %s (#%d) unimplemented.", desc->name, callnum);
84
85 return 1;
86}
87
88
89SyscallReturn
90ignoreFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
91 ThreadContext *tc)
92{
93 int index = 0;
94 warn("ignoring syscall %s(%d, %d, ...)", desc->name,
95 process->getSyscallArg(tc, index), process->getSyscallArg(tc, index));
96
97 return 0;
98}
99
100
101SyscallReturn
102ignoreWarnOnceFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
103 ThreadContext *tc)
104{
105 int index = 0;
106 warn_once("ignoring syscall %s(%d, %d, ...)", desc->name,
107 process->getSyscallArg(tc, index), process->getSyscallArg(tc, index));
108
109 return 0;
110}
111
112
113SyscallReturn
114exitFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
115 ThreadContext *tc)
116{
117 if (process->system->numRunningContexts() == 1) {
118 // Last running context... exit simulator
119 int index = 0;
120 exitSimLoop("target called exit()",
121 process->getSyscallArg(tc, index) & 0xff);
122 } else {
123 // other running threads... just halt this one
124 tc->halt();
125 }
126
127 return 1;
128}
129
130
131SyscallReturn
132exitGroupFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
133 ThreadContext *tc)
134{
135 // really should just halt all thread contexts belonging to this
136 // process in case there's another process running...
137 int index = 0;
138 exitSimLoop("target called exit()",
139 process->getSyscallArg(tc, index) & 0xff);
140
141 return 1;
142}
143
144
145SyscallReturn
146getpagesizeFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
147{
148 return (int)VMPageSize;
149}
150
151
152SyscallReturn
153brkFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
154{
155 // change brk addr to first arg
156 int index = 0;
157 Addr new_brk = p->getSyscallArg(tc, index);
158
159 // in Linux at least, brk(0) returns the current break value
160 // (note that the syscall and the glibc function have different behavior)
161 if (new_brk == 0)
162 return p->brk_point;
163
164 if (new_brk > p->brk_point) {
165 // might need to allocate some new pages
166 for (ChunkGenerator gen(p->brk_point, new_brk - p->brk_point,
167 VMPageSize); !gen.done(); gen.next()) {
168 if (!p->pTable->translate(gen.addr()))
169 p->allocateMem(roundDown(gen.addr(), VMPageSize), VMPageSize);
170
171 // if the address is already there, zero it out
172 else {
173 uint8_t zero = 0;
174 SETranslatingPortProxy &tp = tc->getMemProxy();
175
176 // split non-page aligned accesses
177 Addr next_page = roundUp(gen.addr(), VMPageSize);
178 uint32_t size_needed = next_page - gen.addr();
179 tp.memsetBlob(gen.addr(), zero, size_needed);
180 if (gen.addr() + VMPageSize > next_page &&
181 next_page < new_brk &&
182 p->pTable->translate(next_page))
183 {
184 size_needed = VMPageSize - size_needed;
185 tp.memsetBlob(next_page, zero, size_needed);
186 }
187 }
188 }
189 }
190
191 p->brk_point = new_brk;
192 DPRINTF(SyscallVerbose, "Break Point changed to: %#X\n", p->brk_point);
193 return p->brk_point;
194}
195
196
197SyscallReturn
198closeFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
199{
200 int index = 0;
201 int target_fd = p->getSyscallArg(tc, index);
202 int sim_fd = p->sim_fd(target_fd);
203 int status = 0;
204 if (sim_fd > 2)
205 status = close(sim_fd);
206 if (status >= 0)
207 p->free_fd(target_fd);
208 return status;
209}
210
211
212SyscallReturn
213readFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
214{
215 int index = 0;
216 int fd = p->sim_fd(p->getSyscallArg(tc, index));
217 Addr bufPtr = p->getSyscallArg(tc, index);
218 int nbytes = p->getSyscallArg(tc, index);
219 BufferArg bufArg(bufPtr, nbytes);
220
221 int bytes_read = read(fd, bufArg.bufferPtr(), nbytes);
222
223 if (bytes_read != -1)
224 bufArg.copyOut(tc->getMemProxy());
225
226 return bytes_read;
227}
228
229SyscallReturn
230writeFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
231{
232 int index = 0;
233 int fd = p->sim_fd(p->getSyscallArg(tc, index));
234 Addr bufPtr = p->getSyscallArg(tc, index);
235 int nbytes = p->getSyscallArg(tc, index);
236 BufferArg bufArg(bufPtr, nbytes);
237
238 bufArg.copyIn(tc->getMemProxy());
239
240 int bytes_written = write(fd, bufArg.bufferPtr(), nbytes);
241
242 fsync(fd);
243
244 return bytes_written;
245}
246
247
248SyscallReturn
249lseekFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
250{
251 int index = 0;
252 int fd = p->sim_fd(p->getSyscallArg(tc, index));
253 uint64_t offs = p->getSyscallArg(tc, index);
254 int whence = p->getSyscallArg(tc, index);
255
256 off_t result = lseek(fd, offs, whence);
257
258 return (result == (off_t)-1) ? -errno : result;
259}
260
261
262SyscallReturn
263_llseekFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
264{
265 int index = 0;
266 int fd = p->sim_fd(p->getSyscallArg(tc, index));
267 uint64_t offset_high = p->getSyscallArg(tc, index);
268 uint32_t offset_low = p->getSyscallArg(tc, index);
269 Addr result_ptr = p->getSyscallArg(tc, index);
270 int whence = p->getSyscallArg(tc, index);
271
272 uint64_t offset = (offset_high << 32) | offset_low;
273
274 uint64_t result = lseek(fd, offset, whence);
275 result = TheISA::htog(result);
276
277 if (result == (off_t)-1) {
278 //The seek failed.
279 return -errno;
280 } else {
281 // The seek succeeded.
282 // Copy "result" to "result_ptr"
283 // XXX We'll assume that the size of loff_t is 64 bits on the
284 // target platform
285 BufferArg result_buf(result_ptr, sizeof(result));
286 memcpy(result_buf.bufferPtr(), &result, sizeof(result));
287 result_buf.copyOut(tc->getMemProxy());
288 return 0;
289 }
290
291
292 return (result == (off_t)-1) ? -errno : result;
293}
294
295
296SyscallReturn
297munmapFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
298{
299 // given that we don't really implement mmap, munmap is really easy
300 return 0;
301}
302
303
304const char *hostname = "m5.eecs.umich.edu";
305
306SyscallReturn
307gethostnameFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
308{
309 int index = 0;
310 Addr bufPtr = p->getSyscallArg(tc, index);
311 int name_len = p->getSyscallArg(tc, index);
312 BufferArg name(bufPtr, name_len);
313
314 strncpy((char *)name.bufferPtr(), hostname, name_len);
315
316 name.copyOut(tc->getMemProxy());
317
318 return 0;
319}
320
321SyscallReturn
322getcwdFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
323{
324 int result = 0;
325 int index = 0;
326 Addr bufPtr = p->getSyscallArg(tc, index);
327 unsigned long size = p->getSyscallArg(tc, index);
328 BufferArg buf(bufPtr, size);
329
330 // Is current working directory defined?
331 string cwd = p->getcwd();
332 if (!cwd.empty()) {
333 if (cwd.length() >= size) {
334 // Buffer too small
335 return -ERANGE;
336 }
337 strncpy((char *)buf.bufferPtr(), cwd.c_str(), size);
338 result = cwd.length();
339 }
340 else {
341 if (getcwd((char *)buf.bufferPtr(), size) != NULL) {
342 result = strlen((char *)buf.bufferPtr());
343 }
344 else {
345 result = -1;
346 }
347 }
348
349 buf.copyOut(tc->getMemProxy());
350
351 return (result == -1) ? -errno : result;
352}
353
354
355SyscallReturn
356readlinkFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
357{
358 string path;
359
360 int index = 0;
361 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index)))
362 return (TheISA::IntReg)-EFAULT;
363
364 // Adjust path for current working directory
365 path = p->fullPath(path);
366
367 Addr bufPtr = p->getSyscallArg(tc, index);
368 size_t bufsiz = p->getSyscallArg(tc, index);
369
370 BufferArg buf(bufPtr, bufsiz);
371
372 int result = readlink(path.c_str(), (char *)buf.bufferPtr(), bufsiz);
373
374 buf.copyOut(tc->getMemProxy());
375
376 return (result == -1) ? -errno : result;
377}
378
379SyscallReturn
380unlinkFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
381{
382 string path;
383
384 int index = 0;
385 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index)))
386 return (TheISA::IntReg)-EFAULT;
387
388 // Adjust path for current working directory
389 path = p->fullPath(path);
390
391 int result = unlink(path.c_str());
392 return (result == -1) ? -errno : result;
393}
394
395
396SyscallReturn
397mkdirFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
398{
399 string path;
400
401 int index = 0;
402 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index)))
403 return (TheISA::IntReg)-EFAULT;
404
405 // Adjust path for current working directory
406 path = p->fullPath(path);
407
408 mode_t mode = p->getSyscallArg(tc, index);
409
410 int result = mkdir(path.c_str(), mode);
411 return (result == -1) ? -errno : result;
412}
413
414SyscallReturn
415renameFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
416{
417 string old_name;
418
419 int index = 0;
420 if (!tc->getMemProxy().tryReadString(old_name, p->getSyscallArg(tc, index)))
421 return -EFAULT;
422
423 string new_name;
424
425 if (!tc->getMemProxy().tryReadString(new_name, p->getSyscallArg(tc, index)))
426 return -EFAULT;
427
428 // Adjust path for current working directory
429 old_name = p->fullPath(old_name);
430 new_name = p->fullPath(new_name);
431
432 int64_t result = rename(old_name.c_str(), new_name.c_str());
433 return (result == -1) ? -errno : result;
434}
435
436SyscallReturn
437truncateFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
438{
439 string path;
440
441 int index = 0;
442 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index)))
443 return -EFAULT;
444
445 off_t length = p->getSyscallArg(tc, index);
446
447 // Adjust path for current working directory
448 path = p->fullPath(path);
449
450 int result = truncate(path.c_str(), length);
451 return (result == -1) ? -errno : result;
452}
453
454SyscallReturn
455ftruncateFunc(SyscallDesc *desc, int num,
456 LiveProcess *process, ThreadContext *tc)
457{
458 int index = 0;
459 int fd = process->sim_fd(process->getSyscallArg(tc, index));
460
461 if (fd < 0)
462 return -EBADF;
463
464 off_t length = process->getSyscallArg(tc, index);
465
466 int result = ftruncate(fd, length);
467 return (result == -1) ? -errno : result;
468}
469
470SyscallReturn
471truncate64Func(SyscallDesc *desc, int num,
472 LiveProcess *process, ThreadContext *tc)
473{
474 int index = 0;
475 string path;
476
477 if (!tc->getMemProxy().tryReadString(path, process->getSyscallArg(tc, index)))
478 return -EFAULT;
479
480 int64_t length = process->getSyscallArg(tc, index, 64);
481
482 // Adjust path for current working directory
483 path = process->fullPath(path);
484
485#if NO_STAT64
486 int result = truncate(path.c_str(), length);
487#else
488 int result = truncate64(path.c_str(), length);
489#endif
490 return (result == -1) ? -errno : result;
491}
492
493SyscallReturn
494ftruncate64Func(SyscallDesc *desc, int num,
495 LiveProcess *process, ThreadContext *tc)
496{
497 int index = 0;
498 int fd = process->sim_fd(process->getSyscallArg(tc, index));
499
500 if (fd < 0)
501 return -EBADF;
502
503 int64_t length = process->getSyscallArg(tc, index, 64);
504
505#if NO_STAT64
506 int result = ftruncate(fd, length);
507#else
508 int result = ftruncate64(fd, length);
509#endif
510 return (result == -1) ? -errno : result;
511}
512
513SyscallReturn
514umaskFunc(SyscallDesc *desc, int num, LiveProcess *process, ThreadContext *tc)
515{
516 // Letting the simulated program change the simulator's umask seems like
517 // a bad idea. Compromise by just returning the current umask but not
518 // changing anything.
519 mode_t oldMask = umask(0);
520 umask(oldMask);
521 return (int)oldMask;
522}
523
524SyscallReturn
525chownFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
526{
527 string path;
528
529 int index = 0;
530 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index)))
531 return -EFAULT;
532
533 /* XXX endianess */
534 uint32_t owner = p->getSyscallArg(tc, index);
535 uid_t hostOwner = owner;
536 uint32_t group = p->getSyscallArg(tc, index);
537 gid_t hostGroup = group;
538
539 // Adjust path for current working directory
540 path = p->fullPath(path);
541
542 int result = chown(path.c_str(), hostOwner, hostGroup);
543 return (result == -1) ? -errno : result;
544}
545
546SyscallReturn
547fchownFunc(SyscallDesc *desc, int num, LiveProcess *process, ThreadContext *tc)
548{
549 int index = 0;
550 int fd = process->sim_fd(process->getSyscallArg(tc, index));
551
552 if (fd < 0)
553 return -EBADF;
554
555 /* XXX endianess */
556 uint32_t owner = process->getSyscallArg(tc, index);
557 uid_t hostOwner = owner;
558 uint32_t group = process->getSyscallArg(tc, index);
559 gid_t hostGroup = group;
560
561 int result = fchown(fd, hostOwner, hostGroup);
562 return (result == -1) ? -errno : result;
563}
564
565
566SyscallReturn
567dupFunc(SyscallDesc *desc, int num, LiveProcess *process, ThreadContext *tc)
568{
569 int index = 0;
570 int fd = process->sim_fd(process->getSyscallArg(tc, index));
571 if (fd < 0)
572 return -EBADF;
573
574 Process::FdMap *fdo = process->sim_fd_obj(fd);
575
576 int result = dup(fd);
577 return (result == -1) ? -errno :
578 process->alloc_fd(result, fdo->filename, fdo->flags, fdo->mode, false);
579}
580
581
582SyscallReturn
583fcntlFunc(SyscallDesc *desc, int num, LiveProcess *process,
584 ThreadContext *tc)
585{
586 int index = 0;
587 int fd = process->getSyscallArg(tc, index);
588
589 if (fd < 0 || process->sim_fd(fd) < 0)
590 return -EBADF;
591
592 int cmd = process->getSyscallArg(tc, index);
593 switch (cmd) {
594 case 0: // F_DUPFD
595 // if we really wanted to support this, we'd need to do it
596 // in the target fd space.
597 warn("fcntl(%d, F_DUPFD) not supported, error returned\n", fd);
598 return -EMFILE;
599
600 case 1: // F_GETFD (get close-on-exec flag)
601 case 2: // F_SETFD (set close-on-exec flag)
602 return 0;
603
604 case 3: // F_GETFL (get file flags)
605 case 4: // F_SETFL (set file flags)
606 // not sure if this is totally valid, but we'll pass it through
607 // to the underlying OS
608 warn("fcntl(%d, %d) passed through to host\n", fd, cmd);
609 return fcntl(process->sim_fd(fd), cmd);
610 // return 0;
611
612 case 7: // F_GETLK (get lock)
613 case 8: // F_SETLK (set lock)
614 case 9: // F_SETLKW (set lock and wait)
615 // don't mess with file locking... just act like it's OK
616 warn("File lock call (fcntl(%d, %d)) ignored.\n", fd, cmd);
617 return 0;
618
619 default:
620 warn("Unknown fcntl command %d\n", cmd);
621 return 0;
622 }
623}
624
625SyscallReturn
626fcntl64Func(SyscallDesc *desc, int num, LiveProcess *process,
627 ThreadContext *tc)
628{
629 int index = 0;
630 int fd = process->getSyscallArg(tc, index);
631
632 if (fd < 0 || process->sim_fd(fd) < 0)
633 return -EBADF;
634
635 int cmd = process->getSyscallArg(tc, index);
636 switch (cmd) {
637 case 33: //F_GETLK64
638 warn("fcntl64(%d, F_GETLK64) not supported, error returned\n", fd);
639 return -EMFILE;
640
641 case 34: // F_SETLK64
642 case 35: // F_SETLKW64
643 warn("fcntl64(%d, F_SETLK(W)64) not supported, error returned\n", fd);
644 return -EMFILE;
645
646 default:
647 // not sure if this is totally valid, but we'll pass it through
648 // to the underlying OS
649 warn("fcntl64(%d, %d) passed through to host\n", fd, cmd);
650 return fcntl(process->sim_fd(fd), cmd);
651 // return 0;
652 }
653}
654
655SyscallReturn
656pipePseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
657 ThreadContext *tc)
658{
659 int fds[2], sim_fds[2];
660 int pipe_retval = pipe(fds);
661
662 if (pipe_retval < 0) {
663 // error
664 return pipe_retval;
665 }
666
667 sim_fds[0] = process->alloc_fd(fds[0], "PIPE-READ", O_WRONLY, -1, true);
668 sim_fds[1] = process->alloc_fd(fds[1], "PIPE-WRITE", O_RDONLY, -1, true);
669
670 process->setReadPipeSource(sim_fds[0], sim_fds[1]);
671 // Alpha Linux convention for pipe() is that fd[0] is returned as
672 // the return value of the function, and fd[1] is returned in r20.
673 tc->setIntReg(SyscallPseudoReturnReg, sim_fds[1]);
674 return sim_fds[0];
675}
676
677
678SyscallReturn
679getpidPseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
680 ThreadContext *tc)
681{
682 // Make up a PID. There's no interprocess communication in
683 // fake_syscall mode, so there's no way for a process to know it's
684 // not getting a unique value.
685
686 tc->setIntReg(SyscallPseudoReturnReg, process->ppid());
687 return process->pid();
688}
689
690
691SyscallReturn
692getuidPseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
693 ThreadContext *tc)
694{
695 // Make up a UID and EUID... it shouldn't matter, and we want the
696 // simulation to be deterministic.
697
698 // EUID goes in r20.
699 tc->setIntReg(SyscallPseudoReturnReg, process->euid()); //EUID
700 return process->uid(); // UID
701}
702
703
704SyscallReturn
705getgidPseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
706 ThreadContext *tc)
707{
708 // Get current group ID. EGID goes in r20.
709 tc->setIntReg(SyscallPseudoReturnReg, process->egid()); //EGID
710 return process->gid();
711}
712
713
714SyscallReturn
715setuidFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
716 ThreadContext *tc)
717{
718 // can't fathom why a benchmark would call this.
719 int index = 0;
720 warn("Ignoring call to setuid(%d)\n", process->getSyscallArg(tc, index));
721 return 0;
722}
723
724SyscallReturn
725getpidFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
726 ThreadContext *tc)
727{
728 // Make up a PID. There's no interprocess communication in
729 // fake_syscall mode, so there's no way for a process to know it's
730 // not getting a unique value.
731
732 tc->setIntReg(SyscallPseudoReturnReg, process->ppid()); //PID
733 return process->pid();
734}
735
736SyscallReturn
737getppidFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
738 ThreadContext *tc)
739{
740 return process->ppid();
741}
742
743SyscallReturn
744getuidFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
745 ThreadContext *tc)
746{
747 return process->uid(); // UID
748}
749
750SyscallReturn
751geteuidFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
752 ThreadContext *tc)
753{
754 return process->euid(); // UID
755}
756
757SyscallReturn
758getgidFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
759 ThreadContext *tc)
760{
761 return process->gid();
762}
763
764SyscallReturn
765getegidFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
766 ThreadContext *tc)
767{
768 return process->egid();
769}
770
771
772SyscallReturn
773cloneFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
774 ThreadContext *tc)
775{
776 int index = 0;
777 IntReg flags = process->getSyscallArg(tc, index);
778 IntReg newStack = process->getSyscallArg(tc, index);
779
780 DPRINTF(SyscallVerbose, "In sys_clone:\n");
781 DPRINTF(SyscallVerbose, " Flags=%llx\n", flags);
782 DPRINTF(SyscallVerbose, " Child stack=%llx\n", newStack);
783
784
785 if (flags != 0x10f00) {
786 warn("This sys_clone implementation assumes flags "
787 "CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD "
788 "(0x10f00), and may not work correctly with given flags "
789 "0x%llx\n", flags);
790 }
791
792 ThreadContext* ctc; // child thread context
793 if ( ( ctc = process->findFreeContext() ) != NULL ) {
794 DPRINTF(SyscallVerbose, " Found unallocated thread context\n");
795
796 ctc->clearArchRegs();
797
798 // Arch-specific cloning code
799 #if THE_ISA == ALPHA_ISA or THE_ISA == X86_ISA
800 // Cloning the misc. regs for these archs is enough
801 TheISA::copyMiscRegs(tc, ctc);
802 #elif THE_ISA == SPARC_ISA
803 TheISA::copyRegs(tc, ctc);
804
805 // TODO: Explain what this code actually does :-)
806 ctc->setIntReg(NumIntArchRegs + 6, 0);
807 ctc->setIntReg(NumIntArchRegs + 4, 0);
808 ctc->setIntReg(NumIntArchRegs + 3, NWindows - 2);
809 ctc->setIntReg(NumIntArchRegs + 5, NWindows);
810 ctc->setMiscReg(MISCREG_CWP, 0);
811 ctc->setIntReg(NumIntArchRegs + 7, 0);
812 ctc->setMiscRegNoEffect(MISCREG_TL, 0);
813 ctc->setMiscReg(MISCREG_ASI, ASI_PRIMARY);
814
815 for (int y = 8; y < 32; y++)
816 ctc->setIntReg(y, tc->readIntReg(y));
817 #elif THE_ISA == ARM_ISA
818 TheISA::copyRegs(tc, ctc);
819 #else
820 fatal("sys_clone is not implemented for this ISA\n");
821 #endif
822
823 // Set up stack register
824 ctc->setIntReg(TheISA::StackPointerReg, newStack);
825
826 // Set up syscall return values in parent and child
827 ctc->setIntReg(ReturnValueReg, 0); // return value, child
828
829 // Alpha needs SyscallSuccessReg=0 in child
830 #if THE_ISA == ALPHA_ISA
831 ctc->setIntReg(TheISA::SyscallSuccessReg, 0);
832 #endif
833
834 // In SPARC/Linux, clone returns 0 on pseudo-return register if
835 // parent, non-zero if child
836 #if THE_ISA == SPARC_ISA
837 tc->setIntReg(TheISA::SyscallPseudoReturnReg, 0);
838 ctc->setIntReg(TheISA::SyscallPseudoReturnReg, 1);
839 #endif
840
841 ctc->pcState(tc->nextInstAddr());
842
843 ctc->activate();
844
845 // Should return nonzero child TID in parent's syscall return register,
846 // but for our pthread library any non-zero value will work
847 return 1;
848 } else {
849 fatal("Called sys_clone, but no unallocated thread contexts found!\n");
850 return 0;
851 }
852}
853
854SyscallReturn
855accessFunc(SyscallDesc *desc, int callnum, LiveProcess *p, ThreadContext *tc)
856{
857 int index = 0;
858
859 string path;
860 if (!tc->getMemProxy().tryReadString(path, p->getSyscallArg(tc, index)))
861 return (TheISA::IntReg)-EFAULT;
862
863 // Adjust path for current working directory
864 path = p->fullPath(path);
865
866 mode_t mode = p->getSyscallArg(tc, index);
867
868 int result = access(path.c_str(), mode);
869 return (result == -1) ? -errno : result;
870}