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 <string>
36#include <iostream>
37
38#include "sim/syscall_emul.hh"
39#include "base/chunk_generator.hh"
40#include "base/trace.hh"
41#include "cpu/thread_context.hh"
42#include "cpu/base.hh"
43#include "mem/page_table.hh"
44#include "sim/process.hh"
45
46#include "sim/sim_exit.hh"
47
48using namespace std;
49using namespace TheISA;
50
51void
52SyscallDesc::doSyscall(int callnum, LiveProcess *process, ThreadContext *tc)
53{
54 DPRINTFR(SyscallVerbose, "%d: %s: syscall %s called w/arguments %d,%d,%d,%d\n",
55 curTick,tc->getCpuPtr()->name(), name,
56 tc->getSyscallArg(0),tc->getSyscallArg(1),
57 tc->getSyscallArg(2),tc->getSyscallArg(3));
58
59 SyscallReturn retval = (*funcPtr)(this, callnum, process, tc);
60
61 DPRINTFR(SyscallVerbose, "%d: %s: syscall %s returns %d\n",
62 curTick,tc->getCpuPtr()->name(), name, retval.value());
63
64 if (!(flags & SyscallDesc::SuppressReturnValue))
65 tc->setSyscallReturn(retval);
66}
67
68
69SyscallReturn
70unimplementedFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
71 ThreadContext *tc)
72{
73 fatal("syscall %s (#%d) unimplemented.", desc->name, callnum);
74
75 return 1;
76}
77
78
79SyscallReturn
80ignoreFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
81 ThreadContext *tc)
82{
83 warn("ignoring syscall %s(%d, %d, ...)", desc->name,
84 tc->getSyscallArg(0), tc->getSyscallArg(1));
85
86 return 0;
87}
88
89
90SyscallReturn
91exitFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
92 ThreadContext *tc)
93{
94 if (tc->exit()) {
95 exitSimLoop("target called exit()", tc->getSyscallArg(0) & 0xff);
96 }
97
98 return 1;
99}
100
101
102SyscallReturn
103getpagesizeFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
104{
105 return (int)VMPageSize;
106}
107
108
109SyscallReturn
110obreakFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
111{
112 Addr junk;
113
114 // change brk addr to first arg
115 Addr new_brk = tc->getSyscallArg(0);
116 if (new_brk != 0) {
117 for (ChunkGenerator gen(p->brk_point, new_brk - p->brk_point,
118 VMPageSize); !gen.done(); gen.next()) {
119 if (!p->pTable->translate(gen.addr(), junk))
120 p->pTable->allocate(roundDown(gen.addr(), VMPageSize),
121 VMPageSize);
122 }
123 p->brk_point = new_brk;
124 }
125 DPRINTF(SyscallVerbose, "Break Point changed to: %#X\n", p->brk_point);
126 return p->brk_point;
127}
128
129
130SyscallReturn
131closeFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
132{
133 int target_fd = tc->getSyscallArg(0);
134 int status = close(p->sim_fd(target_fd));
135 if (status >= 0)
136 p->free_fd(target_fd);
137 return status;
138}
139
140
141SyscallReturn
142readFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
143{
144 int fd = p->sim_fd(tc->getSyscallArg(0));
145 int nbytes = tc->getSyscallArg(2);
146 BufferArg bufArg(tc->getSyscallArg(1), nbytes);
147
148 int bytes_read = read(fd, bufArg.bufferPtr(), nbytes);
149
150 if (bytes_read != -1)
151 bufArg.copyOut(tc->getMemPort());
152
153 return bytes_read;
154}
155
156SyscallReturn
157writeFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
158{
159 int fd = p->sim_fd(tc->getSyscallArg(0));
160 int nbytes = tc->getSyscallArg(2);
161 BufferArg bufArg(tc->getSyscallArg(1), nbytes);
162
163 bufArg.copyIn(tc->getMemPort());
164
165 int bytes_written = write(fd, bufArg.bufferPtr(), nbytes);
166
167 fsync(fd);
168
169 return bytes_written;
170}
171
172
173SyscallReturn
174lseekFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
175{
176 int fd = p->sim_fd(tc->getSyscallArg(0));
177 uint64_t offs = tc->getSyscallArg(1);
178 int whence = tc->getSyscallArg(2);
179
180 off_t result = lseek(fd, offs, whence);
181
182 return (result == (off_t)-1) ? -errno : result;
183}
184
185
186SyscallReturn
187_llseekFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
188{
189 int fd = p->sim_fd(tc->getSyscallArg(0));
190 uint64_t offset_high = tc->getSyscallArg(1);
191 uint32_t offset_low = tc->getSyscallArg(2);
192 Addr result_ptr = tc->getSyscallArg(3);
193 int whence = tc->getSyscallArg(4);
194
195 uint64_t offset = (offset_high << 32) | offset_low;
196
197 uint64_t result = lseek(fd, offset, whence);
198 result = TheISA::htog(result);
199
200 if (result == (off_t)-1) {
201 //The seek failed.
202 return -errno;
203 } else {
204 //The seek succeeded.
205 //Copy "result" to "result_ptr"
206 //XXX We'll assume that the size of loff_t is 64 bits on the
207 //target platform
208 BufferArg result_buf(result_ptr, sizeof(result));
209 memcpy(result_buf.bufferPtr(), &result, sizeof(result));
210 result_buf.copyOut(tc->getMemPort());
211 return 0;
212 }
213
214
215 return (result == (off_t)-1) ? -errno : result;
216}
217
218
219SyscallReturn
220munmapFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
221{
222 // given that we don't really implement mmap, munmap is really easy
223 return 0;
224}
225
226
227const char *hostname = "m5.eecs.umich.edu";
228
229SyscallReturn
230gethostnameFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
231{
232 int name_len = tc->getSyscallArg(1);
233 BufferArg name(tc->getSyscallArg(0), name_len);
234
235 strncpy((char *)name.bufferPtr(), hostname, name_len);
236
237 name.copyOut(tc->getMemPort());
238
239 return 0;
240}
241
242SyscallReturn
243getcwdFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
244{
245 int result = 0;
246 unsigned long size = tc->getSyscallArg(1);
247 BufferArg buf(tc->getSyscallArg(0), size);
248
249 // Is current working directory defined?
250 string cwd = p->getcwd();
251 if (!cwd.empty()) {
252 if (cwd.length() >= size) {
253 // Buffer too small
254 return -ERANGE;
255 }
256 strncpy((char *)buf.bufferPtr(), cwd.c_str(), size);
257 result = cwd.length();
258 }
259 else {
260 if (getcwd((char *)buf.bufferPtr(), size) != NULL) {
261 result = strlen((char *)buf.bufferPtr());
262 }
263 else {
264 result = -1;
265 }
266 }
267
268 buf.copyOut(tc->getMemPort());
269
270 return (result == -1) ? -errno : result;
271}
272
273
274SyscallReturn
275readlinkFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
276{
277 string path;
278
279 if (!tc->getMemPort()->tryReadString(path, tc->getSyscallArg(0)))
280 return (TheISA::IntReg)-EFAULT;
281
282 // Adjust path for current working directory
283 path = p->fullPath(path);
284
285 size_t bufsiz = tc->getSyscallArg(2);
286 BufferArg buf(tc->getSyscallArg(1), bufsiz);
287
288 int result = readlink(path.c_str(), (char *)buf.bufferPtr(), bufsiz);
289
290 buf.copyOut(tc->getMemPort());
291
292 return (result == -1) ? -errno : result;
293}
294
295SyscallReturn
296unlinkFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
297{
298 string path;
299
300 if (!tc->getMemPort()->tryReadString(path, tc->getSyscallArg(0)))
301 return (TheISA::IntReg)-EFAULT;
302
303 // Adjust path for current working directory
304 path = p->fullPath(path);
305
306 int result = unlink(path.c_str());
307 return (result == -1) ? -errno : result;
308}
309
310
311SyscallReturn
312mkdirFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
313{
314 string path;
315
316 if (!tc->getMemPort()->tryReadString(path, tc->getSyscallArg(0)))
317 return (TheISA::IntReg)-EFAULT;
318
319 // Adjust path for current working directory
320 path = p->fullPath(path);
321
322 mode_t mode = tc->getSyscallArg(1);
323
324 int result = mkdir(path.c_str(), mode);
325 return (result == -1) ? -errno : result;
326}
327
328SyscallReturn
329renameFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
330{
331 string old_name;
332
333 if (!tc->getMemPort()->tryReadString(old_name, tc->getSyscallArg(0)))
334 return -EFAULT;
335
336 string new_name;
337
338 if (!tc->getMemPort()->tryReadString(new_name, tc->getSyscallArg(1)))
339 return -EFAULT;
340
341 // Adjust path for current working directory
342 old_name = p->fullPath(old_name);
343 new_name = p->fullPath(new_name);
344
345 int64_t result = rename(old_name.c_str(), new_name.c_str());
346 return (result == -1) ? -errno : result;
347}
348
349SyscallReturn
350truncateFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
351{
352 string path;
353
354 if (!tc->getMemPort()->tryReadString(path, tc->getSyscallArg(0)))
355 return -EFAULT;
356
357 off_t length = tc->getSyscallArg(1);
358
359 // Adjust path for current working directory
360 path = p->fullPath(path);
361
362 int result = truncate(path.c_str(), length);
363 return (result == -1) ? -errno : result;
364}
365
366SyscallReturn
367ftruncateFunc(SyscallDesc *desc, int num, LiveProcess *process, ThreadContext *tc)
368{
369 int fd = process->sim_fd(tc->getSyscallArg(0));
370
371 if (fd < 0)
372 return -EBADF;
373
374 off_t length = tc->getSyscallArg(1);
375
376 int result = ftruncate(fd, length);
377 return (result == -1) ? -errno : result;
378}
379
380SyscallReturn
381umaskFunc(SyscallDesc *desc, int num, LiveProcess *process, ThreadContext *tc)
382{
383 // Letting the simulated program change the simulator's umask seems like
384 // a bad idea. Compromise by just returning the current umask but not
385 // changing anything.
386 mode_t oldMask = umask(0);
387 umask(oldMask);
388 return oldMask;
389}
390
391SyscallReturn
392chownFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
393{
394 string path;
395
396 if (!tc->getMemPort()->tryReadString(path, tc->getSyscallArg(0)))
397 return -EFAULT;
398
399 /* XXX endianess */
400 uint32_t owner = tc->getSyscallArg(1);
401 uid_t hostOwner = owner;
402 uint32_t group = tc->getSyscallArg(2);
403 gid_t hostGroup = group;
404
405 // Adjust path for current working directory
406 path = p->fullPath(path);
407
408 int result = chown(path.c_str(), hostOwner, hostGroup);
409 return (result == -1) ? -errno : result;
410}
411
412SyscallReturn
413fchownFunc(SyscallDesc *desc, int num, LiveProcess *process, ThreadContext *tc)
414{
415 int fd = process->sim_fd(tc->getSyscallArg(0));
416
417 if (fd < 0)
418 return -EBADF;
419
420 /* XXX endianess */
421 uint32_t owner = tc->getSyscallArg(1);
422 uid_t hostOwner = owner;
423 uint32_t group = tc->getSyscallArg(2);
424 gid_t hostGroup = group;
425
426 int result = fchown(fd, hostOwner, hostGroup);
427 return (result == -1) ? -errno : result;
428}
429
430
431SyscallReturn
432dupFunc(SyscallDesc *desc, int num, LiveProcess *process, ThreadContext *tc)
433{
434 int fd = process->sim_fd(tc->getSyscallArg(0));
435 if (fd < 0)
436 return -EBADF;
437
438 Process::FdMap *fdo = process->sim_fd_obj(tc->getSyscallArg(0));
439
440 int result = dup(fd);
441 return (result == -1) ? -errno : process->alloc_fd(result, fdo->filename, fdo->flags, fdo->mode, false);
442}
443
444
445SyscallReturn
446fcntlFunc(SyscallDesc *desc, int num, LiveProcess *process,
447 ThreadContext *tc)
448{
449 int fd = tc->getSyscallArg(0);
450
451 if (fd < 0 || process->sim_fd(fd) < 0)
452 return -EBADF;
453
454 int cmd = tc->getSyscallArg(1);
455 switch (cmd) {
456 case 0: // F_DUPFD
457 // if we really wanted to support this, we'd need to do it
458 // in the target fd space.
459 warn("fcntl(%d, F_DUPFD) not supported, error returned\n", fd);
460 return -EMFILE;
461
462 case 1: // F_GETFD (get close-on-exec flag)
463 case 2: // F_SETFD (set close-on-exec flag)
464 return 0;
465
466 case 3: // F_GETFL (get file flags)
467 case 4: // F_SETFL (set file flags)
468 // not sure if this is totally valid, but we'll pass it through
469 // to the underlying OS
470 warn("fcntl(%d, %d) passed through to host\n", fd, cmd);
471 return fcntl(process->sim_fd(fd), cmd);
472 // return 0;
473
474 case 7: // F_GETLK (get lock)
475 case 8: // F_SETLK (set lock)
476 case 9: // F_SETLKW (set lock and wait)
477 // don't mess with file locking... just act like it's OK
478 warn("File lock call (fcntl(%d, %d)) ignored.\n", fd, cmd);
479 return 0;
480
481 default:
482 warn("Unknown fcntl command %d\n", cmd);
483 return 0;
484 }
485}
486
487SyscallReturn
488fcntl64Func(SyscallDesc *desc, int num, LiveProcess *process,
489 ThreadContext *tc)
490{
491 int fd = tc->getSyscallArg(0);
492
493 if (fd < 0 || process->sim_fd(fd) < 0)
494 return -EBADF;
495
496 int cmd = tc->getSyscallArg(1);
497 switch (cmd) {
498 case 33: //F_GETLK64
499 warn("fcntl64(%d, F_GETLK64) not supported, error returned\n", fd);
500 return -EMFILE;
501
502 case 34: // F_SETLK64
503 case 35: // F_SETLKW64
504 warn("fcntl64(%d, F_SETLK(W)64) not supported, error returned\n", fd);
505 return -EMFILE;
506
507 default:
508 // not sure if this is totally valid, but we'll pass it through
509 // to the underlying OS
510 warn("fcntl64(%d, %d) passed through to host\n", fd, cmd);
511 return fcntl(process->sim_fd(fd), cmd);
512 // return 0;
513 }
514}
515
516SyscallReturn
517pipePseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
518 ThreadContext *tc)
519{
520 int fds[2], sim_fds[2];
521 int pipe_retval = pipe(fds);
522
523 if (pipe_retval < 0) {
524 // error
525 return pipe_retval;
526 }
527
528 sim_fds[0] = process->alloc_fd(fds[0], "PIPE-READ", O_WRONLY, -1, true);
529 sim_fds[1] = process->alloc_fd(fds[1], "PIPE-WRITE", O_RDONLY, -1, true);
530
531 process->setReadPipeSource(sim_fds[0], sim_fds[1]);
532 // Alpha Linux convention for pipe() is that fd[0] is returned as
533 // the return value of the function, and fd[1] is returned in r20.
534 tc->setIntReg(SyscallPseudoReturnReg, sim_fds[1]);
535 return sim_fds[0];
536}
537
538
539SyscallReturn
540getpidPseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
541 ThreadContext *tc)
542{
543 // Make up a PID. There's no interprocess communication in
544 // fake_syscall mode, so there's no way for a process to know it's
545 // not getting a unique value.
546
547 tc->setIntReg(SyscallPseudoReturnReg, process->ppid());
548 return process->pid();
549}
550
551
552SyscallReturn
553getuidPseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
554 ThreadContext *tc)
555{
556 // Make up a UID and EUID... it shouldn't matter, and we want the
557 // simulation to be deterministic.
558
559 // EUID goes in r20.
560 tc->setIntReg(SyscallPseudoReturnReg, process->euid()); //EUID
561 return process->uid(); // UID
562}
563
564
565SyscallReturn
566getgidPseudoFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
567 ThreadContext *tc)
568{
569 // Get current group ID. EGID goes in r20.
570 tc->setIntReg(SyscallPseudoReturnReg, process->egid()); //EGID
571 return process->gid();
572}
573
574
575SyscallReturn
576setuidFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
577 ThreadContext *tc)
578{
579 // can't fathom why a benchmark would call this.
580 warn("Ignoring call to setuid(%d)\n", tc->getSyscallArg(0));
581 return 0;
582}
583
584SyscallReturn
585getpidFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
586 ThreadContext *tc)
587{
588 // Make up a PID. There's no interprocess communication in
589 // fake_syscall mode, so there's no way for a process to know it's
590 // not getting a unique value.
591
592 tc->setIntReg(SyscallPseudoReturnReg, process->ppid()); //PID
593 return process->pid();
594}
595
596SyscallReturn
597getppidFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
598 ThreadContext *tc)
599{
600 return process->ppid();
601}
602
603SyscallReturn
604getuidFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
605 ThreadContext *tc)
606{
607 return process->uid(); // UID
608}
609
610SyscallReturn
611geteuidFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
612 ThreadContext *tc)
613{
614 return process->euid(); // UID
615}
616
617SyscallReturn
618getgidFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
619 ThreadContext *tc)
620{
621 return process->gid();
622}
623
624SyscallReturn
625getegidFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
626 ThreadContext *tc)
627{
628 return process->egid();
629}
630
631