1
2 /*--------------------------------------------------------------------*/
3 /*--- Doing syscalls. m_syscall.c ---*/
4 /*--------------------------------------------------------------------*/
5
6 /*
7 This file is part of Valgrind, a dynamic binary instrumentation
8 framework.
9
10 Copyright (C) 2000-2017 Julian Seward
11 jseward@acm.org
12
13 This program is free software; you can redistribute it and/or
14 modify it under the terms of the GNU General Public License as
15 published by the Free Software Foundation; either version 2 of the
16 License, or (at your option) any later version.
17
18 This program is distributed in the hope that it will be useful, but
19 WITHOUT ANY WARRANTY; without even the implied warranty of
20 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21 General Public License for more details.
22
23 You should have received a copy of the GNU General Public License
24 along with this program; if not, write to the Free Software
25 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
26 02111-1307, USA.
27
28 The GNU General Public License is contained in the file COPYING.
29 */
30
31 #include "pub_core_basics.h"
32 #include "pub_core_libcassert.h"
33 #include "pub_core_vki.h"
34 #include "pub_core_vkiscnums.h"
35 #include "pub_core_syscall.h"
36
37 /* ---------------------------------------------------------------------
38 Building syscall return values.
39 ------------------------------------------------------------------ */
40
41 /* Make a SysRes value from a syscall return value. This is
42 platform specific. */
43
44 #if defined(VGP_mips32_linux) || defined(VGP_mips64_linux)
45
VG_(mk_SysRes_mips32_linux)46 SysRes VG_(mk_SysRes_mips32_linux) ( UWord v0, UWord v1, UWord a3 ) {
47 /* MIPS uses a3 != 0 to flag an error */
48 SysRes res;
49 res._isError = (a3 != (UWord)0);
50 res._val = v0;
51 res._valEx = v1;
52 return res;
53 }
54
VG_(mk_SysRes_mips64_linux)55 SysRes VG_(mk_SysRes_mips64_linux) ( ULong v0, ULong v1, ULong a3 ) {
56 /* MIPS uses a3 != 0 to flag an error */
57 SysRes res;
58 res._isError = (a3 != (ULong)0);
59 res._val = v0;
60 res._valEx = v1;
61 return res;
62 }
63
64 /* Generic constructors. */
VG_(mk_SysRes_Error)65 SysRes VG_(mk_SysRes_Error) ( UWord err ) {
66 SysRes r;
67 r._isError = True;
68 r._val = err;
69 r._valEx = 0;
70 return r;
71 }
72
VG_(mk_SysRes_Success)73 SysRes VG_(mk_SysRes_Success) ( UWord res ) {
74 SysRes r;
75 r._isError = False;
76 r._val = res;
77 r._valEx = 0;
78 return r;
79 }
80
VG_(mk_SysRes_SuccessEx)81 SysRes VG_(mk_SysRes_SuccessEx) ( UWord res, UWord resEx ) {
82 SysRes r;
83 r._isError = False;
84 r._val = res;
85 r._valEx = resEx;
86 return r;
87 }
88
89
90 #elif defined(VGO_linux) \
91 && !defined(VGP_mips32_linux) && !defined(VGP_mips64_linux)
92
93 /*
94 From:
95 http://sources.redhat.com/cgi-bin/cvsweb.cgi/libc/sysdeps/unix/sysv/
96 linux/i386/sysdep.h?
97 rev=1.28&content-type=text/x-cvsweb-markup&cvsroot=glibc
98
99 Linux uses a negative return value to indicate syscall errors,
100 unlike most Unices, which use the condition codes' carry flag.
101
102 Since version 2.1 the return value of a system call might be
103 negative even if the call succeeded. E.g., the 'lseek' system call
104 might return a large offset. Therefore we must not anymore test
105 for < 0, but test for a real error by making sure the value in %eax
106 is a real error number. Linus said he will make sure the no
107 syscall returns a value in -1 .. -4095 as a valid result so we can
108 safely test with -4095.
109 */
110
VG_(mk_SysRes_x86_linux)111 SysRes VG_(mk_SysRes_x86_linux) ( Int val ) {
112 SysRes res;
113 res._isError = val >= -4095 && val <= -1;
114 if (res._isError) {
115 res._val = (UInt)(-val);
116 } else {
117 res._val = (UInt)val;
118 }
119 return res;
120 }
121
122 /* Similarly .. */
VG_(mk_SysRes_amd64_linux)123 SysRes VG_(mk_SysRes_amd64_linux) ( Long val ) {
124 SysRes res;
125 res._isError = val >= -4095 && val <= -1;
126 if (res._isError) {
127 res._val = (ULong)(-val);
128 } else {
129 res._val = (ULong)val;
130 }
131 return res;
132 }
133
134 /* PPC uses the CR7.SO bit to flag an error (CR0 in IBM-speak) */
135 /* Note this must be in the bottom bit of the second arg */
VG_(mk_SysRes_ppc32_linux)136 SysRes VG_(mk_SysRes_ppc32_linux) ( UInt val, UInt cr0so ) {
137 SysRes res;
138 res._isError = (cr0so & 1) != 0;
139 res._val = val;
140 return res;
141 }
142
143 /* As per ppc32 version, cr0.so must be in l.s.b. of 2nd arg */
VG_(mk_SysRes_ppc64_linux)144 SysRes VG_(mk_SysRes_ppc64_linux) ( ULong val, ULong cr0so ) {
145 SysRes res;
146 res._isError = (cr0so & 1) != 0;
147 res._val = val;
148 return res;
149 }
150
VG_(mk_SysRes_s390x_linux)151 SysRes VG_(mk_SysRes_s390x_linux) ( Long val ) {
152 SysRes res;
153 res._isError = val >= -4095 && val <= -1;
154 if (res._isError) {
155 res._val = -val;
156 } else {
157 res._val = val;
158 }
159 return res;
160 }
161
VG_(mk_SysRes_arm_linux)162 SysRes VG_(mk_SysRes_arm_linux) ( Int val ) {
163 SysRes res;
164 res._isError = val >= -4095 && val <= -1;
165 if (res._isError) {
166 res._val = (UInt)(-val);
167 } else {
168 res._val = (UInt)val;
169 }
170 return res;
171 }
172
VG_(mk_SysRes_arm64_linux)173 SysRes VG_(mk_SysRes_arm64_linux) ( Long val ) {
174 SysRes res;
175 res._isError = val >= -4095 && val <= -1;
176 if (res._isError) {
177 res._val = (ULong)(-val);
178 } else {
179 res._val = (ULong)val;
180 }
181 return res;
182 }
183
184 /* Generic constructors. */
VG_(mk_SysRes_Error)185 SysRes VG_(mk_SysRes_Error) ( UWord err ) {
186 SysRes r;
187 r._isError = True;
188 r._val = err;
189 return r;
190 }
191
VG_(mk_SysRes_Success)192 SysRes VG_(mk_SysRes_Success) ( UWord res ) {
193 SysRes r;
194 r._isError = False;
195 r._val = res;
196 return r;
197 }
198
199
200 #elif defined(VGO_darwin)
201
202 /* Darwin: Some syscalls return a double-word result. */
VG_(mk_SysRes_x86_darwin)203 SysRes VG_(mk_SysRes_x86_darwin) ( UChar scclass, Bool isErr,
204 UInt wHI, UInt wLO )
205 {
206 SysRes res;
207 res._wHI = 0;
208 res._wLO = 0;
209 res._mode = 0; /* invalid */
210 vg_assert(isErr == False || isErr == True);
211 vg_assert(sizeof(UWord) == sizeof(UInt));
212 switch (scclass) {
213 case VG_DARWIN_SYSCALL_CLASS_UNIX:
214 res._wLO = wLO;
215 res._wHI = wHI;
216 res._mode = isErr ? SysRes_UNIX_ERR : SysRes_UNIX_OK;
217 break;
218 case VG_DARWIN_SYSCALL_CLASS_MACH:
219 vg_assert(!isErr);
220 vg_assert(wHI == 0);
221 res._wLO = wLO;
222 res._mode = SysRes_MACH;
223 break;
224 case VG_DARWIN_SYSCALL_CLASS_MDEP:
225 vg_assert(!isErr);
226 vg_assert(wHI == 0);
227 res._wLO = wLO;
228 res._mode = SysRes_MDEP;
229 break;
230 default:
231 vg_assert(0);
232 }
233 return res;
234 }
235
VG_(mk_SysRes_amd64_darwin)236 SysRes VG_(mk_SysRes_amd64_darwin) ( UChar scclass, Bool isErr,
237 ULong wHI, ULong wLO )
238 {
239 SysRes res;
240 res._wHI = 0;
241 res._wLO = 0;
242 res._mode = 0; /* invalid */
243 vg_assert(isErr == False || isErr == True);
244 vg_assert(sizeof(UWord) == sizeof(ULong));
245 switch (scclass) {
246 case VG_DARWIN_SYSCALL_CLASS_UNIX:
247 res._wLO = wLO;
248 res._wHI = wHI;
249 res._mode = isErr ? SysRes_UNIX_ERR : SysRes_UNIX_OK;
250 break;
251 case VG_DARWIN_SYSCALL_CLASS_MACH:
252 vg_assert(!isErr);
253 vg_assert(wHI == 0);
254 res._wLO = wLO;
255 res._mode = SysRes_MACH;
256 break;
257 case VG_DARWIN_SYSCALL_CLASS_MDEP:
258 vg_assert(!isErr);
259 vg_assert(wHI == 0);
260 res._wLO = wLO;
261 res._mode = SysRes_MDEP;
262 break;
263 default:
264 vg_assert(0);
265 }
266 return res;
267 }
268
269 /* Generic constructors. We assume (without checking if this makes
270 any sense, from the caller's point of view) that these are for the
271 UNIX style of syscall. */
VG_(mk_SysRes_Error)272 SysRes VG_(mk_SysRes_Error) ( UWord err ) {
273 SysRes r;
274 r._wHI = 0;
275 r._wLO = err;
276 r._mode = SysRes_UNIX_ERR;
277 return r;
278 }
279
VG_(mk_SysRes_Success)280 SysRes VG_(mk_SysRes_Success) ( UWord res ) {
281 SysRes r;
282 r._wHI = 0;
283 r._wLO = res;
284 r._mode = SysRes_UNIX_OK;
285 return r;
286 }
287
288
289 #elif defined(VGO_solaris)
290
291 /* Generic constructors. */
VG_(mk_SysRes_Error)292 SysRes VG_(mk_SysRes_Error) ( UWord err ) {
293 SysRes r;
294 r._val = err;
295 r._val2 = 0;
296 r._isError = True;
297 return r;
298 }
299
VG_(mk_SysRes_Success)300 SysRes VG_(mk_SysRes_Success) ( UWord res ) {
301 SysRes r;
302 r._val = res;
303 r._val2 = 0;
304 r._isError = False;
305 return r;
306 }
307
VG_(mk_SysRes_x86_solaris)308 SysRes VG_(mk_SysRes_x86_solaris) ( Bool isErr, UInt val, UInt val2 )
309 {
310 SysRes res;
311
312 // stay sane
313 vg_assert(isErr == True || isErr == False);
314
315 res._val = val;
316 res._val2 = val2;
317 res._isError = isErr;
318 return res;
319 }
320
VG_(mk_SysRes_amd64_solaris)321 SysRes VG_(mk_SysRes_amd64_solaris) ( Bool isErr, ULong val, ULong val2 )
322 {
323 SysRes res;
324
325 // stay sane
326 vg_assert(isErr == True || isErr == False);
327
328 res._val = val;
329 res._val2 = val2;
330 res._isError = isErr;
331 return res;
332 }
333
334 #else
335 # error "Unknown OS"
336 #endif
337
338
339 /* ---------------------------------------------------------------------
340 VG_(do_syscall): A function for doing syscalls.
341 ------------------------------------------------------------------ */
342
343 #if defined(VGP_x86_linux)
344 /* Incoming args (syscall number + up to 6 args) come on the stack.
345 (ie. the C calling convention).
346
347 The syscall number goes in %eax. The args are passed to the syscall in
348 the regs %ebx, %ecx, %edx, %esi, %edi, %ebp, ie. the kernel's syscall
349 calling convention.
350
351 %eax gets the return value. Not sure which registers the kernel
352 clobbers, so we preserve all the callee-save regs (%esi, %edi, %ebx,
353 %ebp).
354 */
355 extern UWord do_syscall_WRK (
356 UWord syscall_no,
357 UWord a1, UWord a2, UWord a3,
358 UWord a4, UWord a5, UWord a6
359 );
360 asm(
361 ".text\n"
362 ".globl do_syscall_WRK\n"
363 "do_syscall_WRK:\n"
364 " .cfi_startproc\n"
365 " push %esi\n"
366 " .cfi_adjust_cfa_offset 4\n"
367 " .cfi_offset %esi, -8\n"
368 " push %edi\n"
369 " .cfi_adjust_cfa_offset 4\n"
370 " .cfi_offset %edi, -12\n"
371 " push %ebx\n"
372 " .cfi_adjust_cfa_offset 4\n"
373 " .cfi_offset %ebx, -16\n"
374 " push %ebp\n"
375 " .cfi_adjust_cfa_offset 4\n"
376 " .cfi_offset %ebp, -20\n"
377 " movl 16+ 4(%esp),%eax\n"
378 " movl 16+ 8(%esp),%ebx\n"
379 " movl 16+12(%esp),%ecx\n"
380 " movl 16+16(%esp),%edx\n"
381 " movl 16+20(%esp),%esi\n"
382 " movl 16+24(%esp),%edi\n"
383 " movl 16+28(%esp),%ebp\n"
384 " int $0x80\n"
385 " popl %ebp\n"
386 " .cfi_adjust_cfa_offset -4\n"
387 " .cfi_restore %ebp\n"
388 " popl %ebx\n"
389 " .cfi_adjust_cfa_offset -4\n"
390 " .cfi_restore %ebx\n"
391 " popl %edi\n"
392 " .cfi_adjust_cfa_offset -4\n"
393 " .cfi_restore %edi\n"
394 " popl %esi\n"
395 " .cfi_adjust_cfa_offset -4\n"
396 " .cfi_restore %esi\n"
397 " ret\n"
398 " .cfi_endproc\n"
399 ".previous\n"
400 );
401
402 #elif defined(VGP_amd64_linux)
403 /* Incoming args (syscall number + up to 6 args) come in %rdi, %rsi,
404 %rdx, %rcx, %r8, %r9, and the last one on the stack (ie. the C
405 calling convention).
406
407 The syscall number goes in %rax. The args are passed to the syscall in
408 the regs %rdi, %rsi, %rdx, %r10, %r8, %r9 (yes, really %r10, not %rcx),
409 ie. the kernel's syscall calling convention.
410
411 %rax gets the return value. %rcx and %r11 are clobbered by the syscall;
412 no matter, they are caller-save (the syscall clobbers no callee-save
413 regs, so we don't have to do any register saving/restoring).
414 */
415 extern UWord do_syscall_WRK (
416 UWord syscall_no,
417 UWord a1, UWord a2, UWord a3,
418 UWord a4, UWord a5, UWord a6
419 );
420 asm(
421 ".text\n"
422 ".globl do_syscall_WRK\n"
423 "do_syscall_WRK:\n"
424 /* Convert function calling convention --> syscall calling
425 convention */
426 " movq %rdi, %rax\n"
427 " movq %rsi, %rdi\n"
428 " movq %rdx, %rsi\n"
429 " movq %rcx, %rdx\n"
430 " movq %r8, %r10\n"
431 " movq %r9, %r8\n"
432 " movq 8(%rsp), %r9\n" /* last arg from stack */
433 " syscall\n"
434 " ret\n"
435 ".previous\n"
436 );
437
438 #elif defined(VGP_ppc32_linux)
439 /* Incoming args (syscall number + up to 6 args) come in %r3:%r9.
440
441 The syscall number goes in %r0. The args are passed to the syscall in
442 the regs %r3:%r8, i.e. the kernel's syscall calling convention.
443
444 The %cr0.so bit flags an error.
445 We return the syscall return value in %r3, and the %cr0.so in
446 the lowest bit of %r4.
447 We return a ULong, of which %r3 is the high word, and %r4 the low.
448 No callee-save regs are clobbered, so no saving/restoring is needed.
449 */
450 extern ULong do_syscall_WRK (
451 UWord syscall_no,
452 UWord a1, UWord a2, UWord a3,
453 UWord a4, UWord a5, UWord a6
454 );
455 asm(
456 ".text\n"
457 ".globl do_syscall_WRK\n"
458 "do_syscall_WRK:\n"
459 " mr 0,3\n"
460 " mr 3,4\n"
461 " mr 4,5\n"
462 " mr 5,6\n"
463 " mr 6,7\n"
464 " mr 7,8\n"
465 " mr 8,9\n"
466 " sc\n" /* syscall: sets %cr0.so on error */
467 " mfcr 4\n" /* %cr -> low word of return var */
468 " rlwinm 4,4,4,31,31\n" /* rotate flag bit so to lsb, and mask it */
469 " blr\n" /* and return */
470 ".previous\n"
471 );
472
473 #elif defined(VGP_ppc64be_linux)
474 /* Due to the need to return 65 bits of result, this is completely
475 different from the ppc32 case. The single arg register points to a
476 7-word block containing the syscall # and the 6 args. The syscall
477 result proper is put in [0] of the block, and %cr0.so is in the
478 bottom bit of [1]. */
479 extern void do_syscall_WRK ( ULong* argblock );
480 asm(
481 ".align 2\n"
482 ".globl do_syscall_WRK\n"
483 ".section \".opd\",\"aw\"\n"
484 ".align 3\n"
485 "do_syscall_WRK:\n"
486 ".quad .do_syscall_WRK,.TOC.@tocbase,0\n"
487 ".previous\n"
488 ".type .do_syscall_WRK,@function\n"
489 ".globl .do_syscall_WRK\n"
490 ".do_syscall_WRK:\n"
491 " std 3,-16(1)\n" /* stash arg */
492 " ld 8, 48(3)\n" /* sc arg 6 */
493 " ld 7, 40(3)\n" /* sc arg 5 */
494 " ld 6, 32(3)\n" /* sc arg 4 */
495 " ld 5, 24(3)\n" /* sc arg 3 */
496 " ld 4, 16(3)\n" /* sc arg 2 */
497 " ld 0, 0(3)\n" /* sc number */
498 " ld 3, 8(3)\n" /* sc arg 1 */
499 " sc\n" /* result in r3 and cr0.so */
500 " ld 5,-16(1)\n" /* reacquire argblock ptr (r5 is caller-save) */
501 " std 3,0(5)\n" /* argblock[0] = r3 */
502 " mfcr 3\n"
503 " srwi 3,3,28\n"
504 " andi. 3,3,1\n"
505 " std 3,8(5)\n" /* argblock[1] = cr0.s0 & 1 */
506 " blr\n"
507 );
508
509 #elif defined(VGP_ppc64le_linux)
510 /* Due to the need to return 65 bits of result, this is completely
511 different from the ppc32 case. The single arg register points to a
512 7-word block containing the syscall # and the 6 args. The syscall
513 result proper is put in [0] of the block, and %cr0.so is in the
514 bottom bit of [1]. */
515 extern void do_syscall_WRK ( ULong* argblock );
516 /* Little Endian supports ELF version 2. In the future, it may support
517 * other versions as well.
518 */
519 asm(
520 ".align 2\n"
521 ".globl do_syscall_WRK\n"
522 ".type do_syscall_WRK,@function\n"
523 "do_syscall_WRK:\n"
524 "#if _CALL_ELF == 2" "\n"
525 "0: addis 2,12,.TOC.-0b@ha\n"
526 " addi 2,2,.TOC.-0b@l\n"
527 " .localentry do_syscall_WRK, .-do_syscall_WRK\n"
528 "#endif" "\n"
529 " std 3,-16(1)\n" /* stash arg */
530 " ld 8, 48(3)\n" /* sc arg 6 */
531 " ld 7, 40(3)\n" /* sc arg 5 */
532 " ld 6, 32(3)\n" /* sc arg 4 */
533 " ld 5, 24(3)\n" /* sc arg 3 */
534 " ld 4, 16(3)\n" /* sc arg 2 */
535 " ld 0, 0(3)\n" /* sc number */
536 " ld 3, 8(3)\n" /* sc arg 1 */
537 " sc\n" /* result in r3 and cr0.so */
538 " ld 5,-16(1)\n" /* reacquire argblock ptr (r5 is caller-save) */
539 " std 3,0(5)\n" /* argblock[0] = r3 */
540 " mfcr 3\n"
541 " srwi 3,3,28\n"
542 " andi. 3,3,1\n"
543 " std 3,8(5)\n" /* argblock[1] = cr0.s0 & 1 */
544 " blr\n"
545 " .size do_syscall_WRK, .-do_syscall_WRK\n"
546 );
547
548 #elif defined(VGP_arm_linux)
549 /* I think the conventions are:
550 args in r0 r1 r2 r3 r4 r5
551 sysno in r7
552 return value in r0, w/ same conventions as x86-linux, viz r0 in
553 -4096 .. -1 is an error value. All other values are success
554 values.
555 */
556 extern UWord do_syscall_WRK (
557 UWord a1, UWord a2, UWord a3,
558 UWord a4, UWord a5, UWord a6,
559 UWord syscall_no
560 );
561 asm(
562 ".text\n"
563 ".globl do_syscall_WRK\n"
564 "do_syscall_WRK:\n"
565 " push {r4, r5, r7}\n"
566 " ldr r4, [sp, #12]\n"
567 " ldr r5, [sp, #16]\n"
568 " ldr r7, [sp, #20]\n"
569 " svc 0x0\n"
570 " pop {r4, r5, r7}\n"
571 " bx lr\n"
572 ".previous\n"
573 );
574
575 #elif defined(VGP_arm64_linux)
576 /* I think the conventions are:
577 args in r0 r1 r2 r3 r4 r5
578 sysno in r8
579 return value in r0, w/ same conventions as x86-linux, viz r0 in
580 -4096 .. -1 is an error value. All other values are success
581 values.
582
583 r0 to r5 remain unchanged, but syscall_no is in r6 and needs
584 to be moved to r8 (??)
585 */
586 extern UWord do_syscall_WRK (
587 UWord a1, UWord a2, UWord a3,
588 UWord a4, UWord a5, UWord a6,
589 UWord syscall_no
590 );
591 asm(
592 ".text\n"
593 ".globl do_syscall_WRK\n"
594 "do_syscall_WRK:\n"
595 " mov x8, x6\n"
596 " mov x6, 0\n"
597 " mov x7, 0\n"
598 " svc 0\n"
599 " ret\n"
600 ".previous\n"
601 );
602
603 #elif defined(VGP_x86_darwin)
604
605 /* Incoming args (syscall number + up to 8 args) come in on the stack
606
607 The kernel's syscall calling convention is:
608 * the syscall number goes in eax
609 * the args are passed to the syscall on the stack,
610 pushed onto the stack R->L (that is, the usual x86
611 calling conventions, with the leftmost arg at the lowest
612 address)
613 Call instruction:
614 * UNIX: sysenter
615 * UNIX: int $0x80
616 * MACH: int $0x81
617 * MDEP: int $0x82
618 Note that the call type can be determined from the syscall number;
619 there is no need to inspect the actual instruction. Although obviously
620 the instruction must match.
621 Return value:
622 * MACH,MDEP: the return value comes back in eax
623 * UNIX: the return value comes back in edx:eax (hi32:lo32)
624 Error:
625 * MACH,MDEP: no error is returned
626 * UNIX: the carry flag indicates success or failure
627
628 nb here, sizeof(UWord) == sizeof(UInt)
629 */
630
631 __private_extern__ ULong
632 do_syscall_unix_WRK ( UWord a1, UWord a2, UWord a3, /* 4(esp)..12(esp) */
633 UWord a4, UWord a5, UWord a6, /* 16(esp)..24(esp) */
634 UWord a7, UWord a8, /* 28(esp)..32(esp) */
635 UWord syscall_no, /* 36(esp) */
636 /*OUT*/UInt* errflag /* 40(esp) */ );
637 // Unix syscall: 64-bit return in edx:eax, with LSB in eax
638 // error indicated by carry flag: clear=good, set=bad
639 asm(".private_extern _do_syscall_unix_WRK\n"
640 "_do_syscall_unix_WRK:\n"
641 " movl 40(%esp), %ecx \n" /* assume syscall success */
642 " movl $0, (%ecx) \n"
643 " movl 36(%esp), %eax \n"
644 " int $0x80 \n"
645 " jnc 1f \n" /* jump if success */
646 " movl 40(%esp), %ecx \n" /* syscall failed - set *errflag */
647 " movl $1, (%ecx) \n"
648 " 1: ret \n"
649 );
650
651 __private_extern__ UInt
652 do_syscall_mach_WRK ( UWord a1, UWord a2, UWord a3, /* 4(esp)..12(esp) */
653 UWord a4, UWord a5, UWord a6, /* 16(esp)..24(esp) */
654 UWord a7, UWord a8, /* 28(esp)..32(esp) */
655 UWord syscall_no /* 36(esp) */ );
656 // Mach trap: 32-bit result in %eax, no error flag
657 asm(".private_extern _do_syscall_mach_WRK\n"
658 "_do_syscall_mach_WRK:\n"
659 " movl 36(%esp), %eax \n"
660 " int $0x81 \n"
661 " ret \n"
662 );
663
664 __private_extern__ UInt
665 do_syscall_mdep_WRK ( UWord a1, UWord a2, UWord a3, /* 4(esp)..12(esp) */
666 UWord a4, UWord a5, UWord a6, /* 16(esp)..24(esp) */
667 UWord a7, UWord a8, /* 28(esp)..32(esp) */
668 UWord syscall_no /* 36(esp) */ );
669 // mdep trap: 32-bit result in %eax, no error flag
670 asm(
671 ".private_extern _do_syscall_mdep_WRK\n"
672 "_do_syscall_mdep_WRK:\n"
673 " movl 36(%esp), %eax \n"
674 " int $0x82 \n"
675 " ret \n"
676 );
677
678
679 #elif defined(VGP_amd64_darwin)
680
681 /* Incoming args (syscall number + up to 8 args) come in registers and stack
682
683 The kernel's syscall calling convention is:
684 * the syscall number goes in rax
685 * the args are passed to the syscall in registers and the stack
686 * the call instruction is 'syscall'
687 Return value:
688 * MACH,MDEP: the return value comes back in rax
689 * UNIX: the return value comes back in rdx:rax (hi64:lo64)
690 Error:
691 * MACH,MDEP: no error is returned
692 * UNIX: the carry flag indicates success or failure
693
694 nb here, sizeof(UWord) == sizeof(ULong)
695 */
696
697 __private_extern__ UWord
698 do_syscall_unix_WRK ( UWord a1, UWord a2, UWord a3, /* rdi, rsi, rdx */
699 UWord a4, UWord a5, UWord a6, /* rcx, r8, r9 */
700 UWord a7, UWord a8, /* 8(rsp), 16(rsp) */
701 UWord syscall_no, /* 24(rsp) */
702 /*OUT*/ULong* errflag, /* 32(rsp) */
703 /*OUT*/ULong* res2 ); /* 40(rsp) */
704 // Unix syscall: 128-bit return in rax:rdx, with LSB in rax
705 // error indicated by carry flag: clear=good, set=bad
706 asm(".private_extern _do_syscall_unix_WRK\n"
707 "_do_syscall_unix_WRK:\n"
708 " movq %rcx, %r10 \n" /* pass rcx in r10 instead */
709 " movq 32(%rsp), %rax \n" /* assume syscall success */
710 " movq $0, (%rax) \n"
711 " movq 24(%rsp), %rax \n" /* load syscall_no */
712 " syscall \n"
713 " jnc 1f \n" /* jump if success */
714 " movq 32(%rsp), %rcx \n" /* syscall failed - set *errflag */
715 " movq $1, (%rcx) \n"
716 " 1: movq 40(%rsp), %rcx \n" /* save 2nd result word */
717 " movq %rdx, (%rcx) \n"
718 " retq \n" /* return 1st result word */
719 );
720
721 __private_extern__ UWord
722 do_syscall_mach_WRK ( UWord a1, UWord a2, UWord a3, /* rdi, rsi, rdx */
723 UWord a4, UWord a5, UWord a6, /* rcx, r8, r9 */
724 UWord a7, UWord a8, /* 8(rsp), 16(rsp) */
725 UWord syscall_no ); /* 24(rsp) */
726 // Mach trap: 64-bit result, no error flag
727 asm(".private_extern _do_syscall_mach_WRK\n"
728 "_do_syscall_mach_WRK:\n"
729 " movq %rcx, %r10 \n" /* pass rcx in r10 instead */
730 " movq 24(%rsp), %rax \n" /* load syscall_no */
731 " syscall \n"
732 " retq \n"
733 );
734
735 #elif defined(VGP_s390x_linux)
736
do_syscall_WRK(UWord syscall_no,UWord arg1,UWord arg2,UWord arg3,UWord arg4,UWord arg5,UWord arg6)737 static UWord do_syscall_WRK (
738 UWord syscall_no,
739 UWord arg1, UWord arg2, UWord arg3,
740 UWord arg4, UWord arg5, UWord arg6
741 )
742 {
743 register UWord __arg1 asm("2") = arg1;
744 register UWord __arg2 asm("3") = arg2;
745 register UWord __arg3 asm("4") = arg3;
746 register UWord __arg4 asm("5") = arg4;
747 register UWord __arg5 asm("6") = arg5;
748 register UWord __arg6 asm("7") = arg6;
749 register ULong __svcres asm("2");
750
751 __asm__ __volatile__ (
752 "lgr %%r1,%1\n\t"
753 "svc 0\n\t"
754 : "=d" (__svcres)
755 : "a" (syscall_no),
756 "0" (__arg1),
757 "d" (__arg2),
758 "d" (__arg3),
759 "d" (__arg4),
760 "d" (__arg5),
761 "d" (__arg6)
762 : "1", "cc", "memory");
763
764 return (UWord) (__svcres);
765 }
766
767 #elif defined(VGP_mips32_linux)
768 /* Incoming args (syscall number + up to 6 args) come in a0 - a3 and stack.
769
770 The syscall number goes in v0. The args are passed to the syscall in
771 the regs a0 - a3 and stack, i.e. the kernel's syscall calling convention.
772
773 (a3 != 0) flags an error.
774 We return the syscall return value in v0.
775 MIPS version
776 */
777 extern int do_syscall_WRK (
778 int a1, int a2, int a3,
779 int a4, int a5, int a6, int syscall_no, UWord *err,
780 UWord *valHi, UWord* valLo
781 );
782 asm (
783 ".text \n\t"
784 ".globl do_syscall_WRK \n\t"
785 ".type do_syscall_WRK, @function \n\t"
786 ".set push \n\t"
787 ".set noreorder \n\t"
788 "do_syscall_WRK: \n\t"
789 " lw $2, 24($29) \n\t"
790 " syscall \n\t"
791 " lw $8, 28($29) \n\t"
792 " sw $7, ($8) \n\t"
793 " lw $8, 32($29) \n\t"
794 " sw $3, ($8) \n\t" /* store valHi */
795 " lw $8, 36($29) \n\t"
796 " jr $31 \n\t"
797 " sw $2, ($8) \n\t" /* store valLo */
798 ".size do_syscall_WRK, .-do_syscall_WRK \n\t"
799 ".set pop \n\t"
800 ".previous \n\t"
801 );
802
803 #elif defined(VGP_mips64_linux)
804 extern UWord do_syscall_WRK ( UWord a1, UWord a2, UWord a3, UWord a4, UWord a5,
805 UWord a6, UWord syscall_no, ULong* V1_A3_val );
806 asm (
807 ".text \n\t"
808 ".globl do_syscall_WRK \n\t"
809 ".type do_syscall_WRK, @function \n\t"
810 ".set push \n\t"
811 ".set noreorder \n\t"
812 "do_syscall_WRK: \n\t"
813 " daddiu $29, $29, -8 \n\t"
814 " sd $11, 0($29) \n\t"
815 " move $2, $10 \n\t"
816 " syscall \n\t"
817 " ld $11, 0($29) \n\t"
818 " daddiu $29, $29, 8 \n\t"
819 " sd $3, 0($11) \n\t" /* store v1 in last param */
820 " jr $31 \n\t"
821 " sd $7, 8($11) \n\t" /* store a3 in last param */
822 ".size do_syscall_WRK, .-do_syscall_WRK \n\t"
823 ".set pop \n\t"
824 ".previous \n\t"
825 );
826
827 #elif defined(VGP_x86_solaris)
828
829 extern ULong
830 do_syscall_WRK(UWord a1, UWord a2, UWord a3, /* 4(esp)..12(esp) */
831 UWord a4, UWord a5, UWord a6, /* 16(esp)..24(esp) */
832 UWord a7, UWord a8, /* 28(esp)..32(esp) */
833 UWord syscall_no, /* 36(esp) */
834 /*OUT*/UInt *errflag); /* 40(esp) */
835 /* Classic unix syscall.. parameters on the stack, an unused (by the kernel)
836 return address at 0(esp), a sysno in eax, a result in edx:eax, the carry
837 flag set on error. */
838 __asm__ (
839 ".text\n"
840 ".globl do_syscall_WRK\n"
841 "do_syscall_WRK:\n"
842 " movl 40(%esp), %ecx\n" /* assume syscall success */
843 " movl $0, (%ecx)\n"
844 " movl 36(%esp), %eax\n"
845 " int $0x91\n"
846 " jnc 1f\n" /* jump if success */
847 " movl 40(%esp), %ecx\n" /* syscall failed - set *errflag */
848 " movl $1, (%ecx)\n"
849 "1: ret\n"
850 ".previous\n"
851 );
852
853 extern ULong
854 do_syscall_fast_WRK(UWord syscall_no); /* 4(esp) */
855 /* Fasttrap syscall.. no parameters, a sysno in eax, a result in edx:eax,
856 never fails (if the sysno is valid). */
857 __asm__ (
858 ".text\n"
859 ".globl do_syscall_fast_WRK\n"
860 "do_syscall_fast_WRK:\n"
861 " movl 4(%esp), %eax\n"
862 " int $0xD2\n"
863 " ret\n"
864 ".previous\n"
865 );
866
867 #elif defined(VGP_amd64_solaris)
868
869 extern ULong
870 do_syscall_WRK(UWord a1, UWord a2, UWord a3, /* rdi, rsi, rdx */
871 UWord a4, UWord a5, UWord a6, /* rcx, r8, r9 */
872 UWord a7, UWord a8, /* 8(rsp), 16(rsp) */
873 UWord syscall_no, /* 24(rsp) */
874 /*OUT*/ULong *errflag, /* 32(rsp) */
875 /*OUT*/ULong *res2); /* 40(rsp) */
876 /* First 6 parameters in registers rdi, rsi, rdx, r10, r8, r9, next
877 2 parameters on the stack, an unused (by the kernel) return address at
878 0(rsp), a sysno in rax, a result in rdx:rax, the carry flag set on
879 error. */
880 __asm__ (
881 ".text\n"
882 ".globl do_syscall_WRK\n"
883 "do_syscall_WRK:\n"
884 " movq %rcx, %r10\n" /* pass rcx in r10 instead */
885 " movq 32(%rsp), %rcx\n" /* assume syscall success */
886 " movq $0, (%rcx)\n"
887 " movq 24(%rsp), %rax\n"
888 " syscall\n"
889 " jnc 1f\n" /* jump if success */
890 " movq 32(%rsp), %rcx\n" /* syscall failed - set *errflag */
891 " movq $1, (%rcx)\n"
892 "1: movq 40(%rsp), %rcx\n" /* save 2nd result word */
893 " movq %rdx, (%rcx)\n"
894 " ret\n"
895 ".previous\n"
896 );
897
898 extern ULong
899 do_syscall_fast_WRK(UWord syscall_no, /* rdi */
900 /*OUT*/ULong *res2); /* rsi */
901 /* Fasttrap syscall.. no parameters, a sysno in rax, a result in rdx:rax,
902 never fails (if the sysno is valid). */
903 __asm__ (
904 ".text\n"
905 ".globl do_syscall_fast_WRK\n"
906 "do_syscall_fast_WRK:\n"
907 " movq %rdi, %rax\n"
908 " int $0xD2\n"
909 " movq %rdx, (%rsi)\n" /* save 2nd result word */
910 " ret\n"
911 ".previous\n"
912 );
913
914 #else
915 # error Unknown platform
916 #endif
917
918
919 /* Finally, the generic code. This sends the call to the right
920 helper. */
921
VG_(do_syscall)922 SysRes VG_(do_syscall) ( UWord sysno, UWord a1, UWord a2, UWord a3,
923 UWord a4, UWord a5, UWord a6,
924 UWord a7, UWord a8 )
925 {
926 # if defined(VGP_x86_linux)
927 UWord val = do_syscall_WRK(sysno,a1,a2,a3,a4,a5,a6);
928 return VG_(mk_SysRes_x86_linux)( val );
929
930 # elif defined(VGP_amd64_linux)
931 UWord val = do_syscall_WRK(sysno,a1,a2,a3,a4,a5,a6);
932 return VG_(mk_SysRes_amd64_linux)( val );
933
934 # elif defined(VGP_ppc32_linux)
935 ULong ret = do_syscall_WRK(sysno,a1,a2,a3,a4,a5,a6);
936 UInt val = (UInt)(ret>>32);
937 UInt cr0so = (UInt)(ret);
938 return VG_(mk_SysRes_ppc32_linux)( val, cr0so );
939
940 # elif defined(VGP_ppc64be_linux) || defined(VGP_ppc64le_linux)
941 ULong argblock[7];
942 argblock[0] = sysno;
943 argblock[1] = a1;
944 argblock[2] = a2;
945 argblock[3] = a3;
946 argblock[4] = a4;
947 argblock[5] = a5;
948 argblock[6] = a6;
949 do_syscall_WRK( &argblock[0] );
950 return VG_(mk_SysRes_ppc64_linux)( argblock[0], argblock[1] );
951
952 # elif defined(VGP_arm_linux)
953 UWord val = do_syscall_WRK(a1,a2,a3,a4,a5,a6,sysno);
954 return VG_(mk_SysRes_arm_linux)( val );
955
956 # elif defined(VGP_arm64_linux)
957 UWord val = do_syscall_WRK(a1,a2,a3,a4,a5,a6,sysno);
958 return VG_(mk_SysRes_arm64_linux)( val );
959
960 # elif defined(VGP_x86_darwin)
961 UInt wLO = 0, wHI = 0, err = 0;
962 ULong u64;
963 UChar scclass = VG_DARWIN_SYSNO_CLASS(sysno);
964 switch (scclass) {
965 case VG_DARWIN_SYSCALL_CLASS_UNIX:
966 u64 = do_syscall_unix_WRK(a1,a2,a3,a4,a5,a6,a7,a8,
967 VG_DARWIN_SYSNO_FOR_KERNEL(sysno), &err);
968 wLO = (UInt)u64;
969 wHI = (UInt)(u64 >> 32);
970 break;
971 case VG_DARWIN_SYSCALL_CLASS_MACH:
972 wLO = do_syscall_mach_WRK(a1,a2,a3,a4,a5,a6,a7,a8,
973 VG_DARWIN_SYSNO_FOR_KERNEL(sysno));
974 err = 0;
975 break;
976 case VG_DARWIN_SYSCALL_CLASS_MDEP:
977 wLO = do_syscall_mdep_WRK(a1,a2,a3,a4,a5,a6,a7,a8,
978 VG_DARWIN_SYSNO_FOR_KERNEL(sysno));
979 err = 0;
980 break;
981 default:
982 vg_assert(0);
983 break;
984 }
985 return VG_(mk_SysRes_x86_darwin)( scclass, err ? True : False, wHI, wLO );
986
987 # elif defined(VGP_amd64_darwin)
988 ULong wLO = 0, wHI = 0, err = 0;
989 UChar scclass = VG_DARWIN_SYSNO_CLASS(sysno);
990 switch (scclass) {
991 case VG_DARWIN_SYSCALL_CLASS_UNIX:
992 wLO = do_syscall_unix_WRK(a1,a2,a3,a4,a5,a6,a7,a8,
993 VG_DARWIN_SYSNO_FOR_KERNEL(sysno), &err, &wHI);
994 break;
995 case VG_DARWIN_SYSCALL_CLASS_MACH:
996 case VG_DARWIN_SYSCALL_CLASS_MDEP:
997 wLO = do_syscall_mach_WRK(a1,a2,a3,a4,a5,a6,a7,a8,
998 VG_DARWIN_SYSNO_FOR_KERNEL(sysno));
999 err = 0;
1000 break;
1001 default:
1002 vg_assert(0);
1003 break;
1004 }
1005 return VG_(mk_SysRes_amd64_darwin)( scclass, err ? True : False, wHI, wLO );
1006
1007 #elif defined(VGP_s390x_linux)
1008 UWord val;
1009
1010 if (sysno == __NR_mmap) {
1011 ULong argbuf[6];
1012
1013 argbuf[0] = a1;
1014 argbuf[1] = a2;
1015 argbuf[2] = a3;
1016 argbuf[3] = a4;
1017 argbuf[4] = a5;
1018 argbuf[5] = a6;
1019 val = do_syscall_WRK(sysno,(UWord)&argbuf[0],0,0,0,0,0);
1020 } else {
1021 val = do_syscall_WRK(sysno,a1,a2,a3,a4,a5,a6);
1022 }
1023
1024 return VG_(mk_SysRes_s390x_linux)( val );
1025
1026 #elif defined(VGP_mips32_linux)
1027 UWord err = 0;
1028 UWord valHi = 0;
1029 UWord valLo = 0;
1030 (void) do_syscall_WRK(a1,a2,a3,a4,a5,a6, sysno,&err,&valHi,&valLo);
1031 return VG_(mk_SysRes_mips32_linux)( valLo, valHi, (ULong)err );
1032
1033 #elif defined(VGP_mips64_linux)
1034 ULong v1_a3[2];
1035 v1_a3[0] = 0xFF00;
1036 v1_a3[1] = 0xFF00;
1037 ULong V0 = do_syscall_WRK(a1,a2,a3,a4,a5,a6,sysno,v1_a3);
1038 ULong V1 = (ULong)v1_a3[0];
1039 ULong A3 = (ULong)v1_a3[1];
1040 return VG_(mk_SysRes_mips64_linux)( V0, V1, A3 );
1041
1042 # elif defined(VGP_x86_solaris)
1043 UInt val, val2, err = False;
1044 Bool restart;
1045 ULong u64;
1046 UChar ssclass = VG_SOLARIS_SYSNO_CLASS(sysno);
1047
1048 switch (ssclass) {
1049 case VG_SOLARIS_SYSCALL_CLASS_CLASSIC:
1050 /* The Solaris kernel does not restart syscalls automatically so it
1051 is done here. */
1052 do {
1053 u64 = do_syscall_WRK(a1,a2,a3,a4,a5,a6,a7,a8,
1054 VG_SOLARIS_SYSNO_INDEX(sysno), &err);
1055 val = (UInt)u64;
1056 restart = err && (val == VKI_EINTR || val == VKI_ERESTART);
1057 } while (restart);
1058 break;
1059 case VG_SOLARIS_SYSCALL_CLASS_FASTTRAP:
1060 u64 = do_syscall_fast_WRK(VG_SOLARIS_SYSNO_INDEX(sysno));
1061 break;
1062 default:
1063 vg_assert(0);
1064 break;
1065 }
1066
1067 val = (UInt)u64;
1068 val2 = (UInt)(u64 >> 32);
1069 return VG_(mk_SysRes_x86_solaris)(err ? True : False, val,
1070 err ? 0 : val2);
1071
1072 # elif defined(VGP_amd64_solaris)
1073 ULong val, val2, err = False;
1074 Bool restart;
1075 UChar ssclass = VG_SOLARIS_SYSNO_CLASS(sysno);
1076
1077 switch (ssclass) {
1078 case VG_SOLARIS_SYSCALL_CLASS_CLASSIC:
1079 /* The Solaris kernel does not restart syscalls automatically so it
1080 is done here. */
1081 do {
1082 val = do_syscall_WRK(a1,a2,a3,a4,a5,a6,a7,a8,
1083 VG_SOLARIS_SYSNO_INDEX(sysno), &err, &val2);
1084 restart = err && (val == VKI_EINTR || val == VKI_ERESTART);
1085 } while (restart);
1086 break;
1087 case VG_SOLARIS_SYSCALL_CLASS_FASTTRAP:
1088 val = do_syscall_fast_WRK(VG_SOLARIS_SYSNO_INDEX(sysno), &val2);
1089 break;
1090 default:
1091 vg_assert(0);
1092 break;
1093 }
1094
1095 return VG_(mk_SysRes_amd64_solaris)(err ? True : False, val,
1096 err ? 0 : val2);
1097
1098 #else
1099 # error Unknown platform
1100 #endif
1101 }
1102
1103 /* ---------------------------------------------------------------------
1104 Names of errors.
1105 ------------------------------------------------------------------ */
1106
1107 /* Return a string which gives the name of an error value. Note,
1108 unlike the standard C syserror fn, the returned string is not
1109 malloc-allocated or writable -- treat it as a constant.
1110 TODO: implement this properly. */
1111
VG_(strerror)1112 const HChar* VG_(strerror) ( UWord errnum )
1113 {
1114 switch (errnum) {
1115 case VKI_EPERM: return "Operation not permitted";
1116 case VKI_ENOENT: return "No such file or directory";
1117 case VKI_ESRCH: return "No such process";
1118 case VKI_EINTR: return "Interrupted system call";
1119 case VKI_EIO: return "Input/output error";
1120 case VKI_ENXIO: return "No such device or address";
1121 case VKI_E2BIG: return "Argument list too long";
1122 case VKI_ENOEXEC: return "Exec format error";
1123 case VKI_EBADF: return "Bad file descriptor";
1124 case VKI_ECHILD: return "No child processes";
1125 case VKI_EAGAIN: return "Resource temporarily unavailable";
1126 case VKI_ENOMEM: return "Cannot allocate memory";
1127 case VKI_EACCES: return "Permission denied";
1128 case VKI_EFAULT: return "Bad address";
1129 case VKI_ENOTBLK: return "Block device required";
1130 case VKI_EBUSY: return "Device or resource busy";
1131 case VKI_EEXIST: return "File exists";
1132 case VKI_EXDEV: return "Invalid cross-device link";
1133 case VKI_ENODEV: return "No such device";
1134 case VKI_ENOTDIR: return "Not a directory";
1135 case VKI_EISDIR: return "Is a directory";
1136 case VKI_EINVAL: return "Invalid argument";
1137 case VKI_ENFILE: return "Too many open files in system";
1138 case VKI_EMFILE: return "Too many open files";
1139 case VKI_ENOTTY: return "Inappropriate ioctl for device";
1140 case VKI_ETXTBSY: return "Text file busy";
1141 case VKI_EFBIG: return "File too large";
1142 case VKI_ENOSPC: return "No space left on device";
1143 case VKI_ESPIPE: return "Illegal seek";
1144 case VKI_EROFS: return "Read-only file system";
1145 case VKI_EMLINK: return "Too many links";
1146 case VKI_EPIPE: return "Broken pipe";
1147 case VKI_EDOM: return "Numerical argument out of domain";
1148 case VKI_ERANGE: return "Numerical result out of range";
1149
1150 case VKI_ENOSYS: return "Function not implemented";
1151 case VKI_EOVERFLOW: return "Value too large for defined data type";
1152 # if defined(VKI_ERESTARTSYS)
1153 case VKI_ERESTARTSYS: return "ERESTARTSYS";
1154 # endif
1155 default: return "VG_(strerror): unknown error";
1156 }
1157 }
1158
1159
1160 /*--------------------------------------------------------------------*/
1161 /*--- end ---*/
1162 /*--------------------------------------------------------------------*/
1163