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spapr: Fix support of POWER5+ processors
[qemu.git] / linux-user / i386 / signal.c
blob4372621a4d206c3488830d5ad6202b9e95e24244
1 /*
2 * Emulation of Linux signals
3 *
4 * Copyright (c) 2003 Fabrice Bellard
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, see <http://www.gnu.org/licenses/>.
18 */
19 #include "qemu/osdep.h"
20 #include "qemu.h"
21 #include "user-internals.h"
22 #include "signal-common.h"
23 #include "linux-user/trace.h"
24
25 /* from the Linux kernel - /arch/x86/include/uapi/asm/sigcontext.h */
26
27 struct target_fpreg {
28 uint16_t significand[4];
29 uint16_t exponent;
30 };
31
32 struct target_fpxreg {
33 uint16_t significand[4];
34 uint16_t exponent;
35 uint16_t padding[3];
36 };
37
38 struct target_xmmreg {
39 uint32_t element[4];
40 };
41
42 struct target_fpstate_32 {
43 /* Regular FPU environment */
44 uint32_t cw;
45 uint32_t sw;
46 uint32_t tag;
47 uint32_t ipoff;
48 uint32_t cssel;
49 uint32_t dataoff;
50 uint32_t datasel;
51 struct target_fpreg st[8];
52 uint16_t status;
53 uint16_t magic; /* 0xffff = regular FPU data only */
54
55 /* FXSR FPU environment */
56 uint32_t _fxsr_env[6]; /* FXSR FPU env is ignored */
57 uint32_t mxcsr;
58 uint32_t reserved;
59 struct target_fpxreg fxsr_st[8]; /* FXSR FPU reg data is ignored */
60 struct target_xmmreg xmm[8];
61 uint32_t padding[56];
62 };
63
64 struct target_fpstate_64 {
65 /* FXSAVE format */
66 uint16_t cw;
67 uint16_t sw;
68 uint16_t twd;
69 uint16_t fop;
70 uint64_t rip;
71 uint64_t rdp;
72 uint32_t mxcsr;
73 uint32_t mxcsr_mask;
74 uint32_t st_space[32];
75 uint32_t xmm_space[64];
76 uint32_t reserved[24];
77 };
78
79 #ifndef TARGET_X86_64
80 # define target_fpstate target_fpstate_32
81 #else
82 # define target_fpstate target_fpstate_64
83 #endif
84
85 struct target_sigcontext_32 {
86 uint16_t gs, __gsh;
87 uint16_t fs, __fsh;
88 uint16_t es, __esh;
89 uint16_t ds, __dsh;
90 uint32_t edi;
91 uint32_t esi;
92 uint32_t ebp;
93 uint32_t esp;
94 uint32_t ebx;
95 uint32_t edx;
96 uint32_t ecx;
97 uint32_t eax;
98 uint32_t trapno;
99 uint32_t err;
100 uint32_t eip;
101 uint16_t cs, __csh;
102 uint32_t eflags;
103 uint32_t esp_at_signal;
104 uint16_t ss, __ssh;
105 uint32_t fpstate; /* pointer */
106 uint32_t oldmask;
107 uint32_t cr2;
108 };
109
110 struct target_sigcontext_64 {
111 uint64_t r8;
112 uint64_t r9;
113 uint64_t r10;
114 uint64_t r11;
115 uint64_t r12;
116 uint64_t r13;
117 uint64_t r14;
118 uint64_t r15;
119
120 uint64_t rdi;
121 uint64_t rsi;
122 uint64_t rbp;
123 uint64_t rbx;
124 uint64_t rdx;
125 uint64_t rax;
126 uint64_t rcx;
127 uint64_t rsp;
128 uint64_t rip;
129
130 uint64_t eflags;
131
132 uint16_t cs;
133 uint16_t gs;
134 uint16_t fs;
135 uint16_t ss;
136
137 uint64_t err;
138 uint64_t trapno;
139 uint64_t oldmask;
140 uint64_t cr2;
141
142 uint64_t fpstate; /* pointer */
143 uint64_t padding[8];
144 };
145
146 #ifndef TARGET_X86_64
147 # define target_sigcontext target_sigcontext_32
148 #else
149 # define target_sigcontext target_sigcontext_64
150 #endif
151
152 /* see Linux/include/uapi/asm-generic/ucontext.h */
153 struct target_ucontext {
154 abi_ulong tuc_flags;
155 abi_ulong tuc_link;
156 target_stack_t tuc_stack;
157 struct target_sigcontext tuc_mcontext;
158 target_sigset_t tuc_sigmask; /* mask last for extensibility */
159 };
160
161 #ifndef TARGET_X86_64
162 struct sigframe {
163 abi_ulong pretcode;
164 int sig;
165 struct target_sigcontext sc;
166 struct target_fpstate fpstate;
167 abi_ulong extramask[TARGET_NSIG_WORDS-1];
168 char retcode[8];
169 };
170
171 struct rt_sigframe {
172 abi_ulong pretcode;
173 int sig;
174 abi_ulong pinfo;
175 abi_ulong puc;
176 struct target_siginfo info;
177 struct target_ucontext uc;
178 struct target_fpstate fpstate;
179 char retcode[8];
180 };
181
182 #else
183
184 struct rt_sigframe {
185 abi_ulong pretcode;
186 struct target_ucontext uc;
187 struct target_siginfo info;
188 struct target_fpstate fpstate;
189 };
190
191 #endif
192
193 /*
194 * Set up a signal frame.
195 */
196
197 /* XXX: save x87 state */
198 static void setup_sigcontext(struct target_sigcontext *sc,
199 struct target_fpstate *fpstate, CPUX86State *env, abi_ulong mask,
200 abi_ulong fpstate_addr)
201 {
202 CPUState *cs = env_cpu(env);
203 #ifndef TARGET_X86_64
204 uint16_t magic;
205
206 /* already locked in setup_frame() */
207 __put_user(env->segs[R_GS].selector, (unsigned int *)&sc->gs);
208 __put_user(env->segs[R_FS].selector, (unsigned int *)&sc->fs);
209 __put_user(env->segs[R_ES].selector, (unsigned int *)&sc->es);
210 __put_user(env->segs[R_DS].selector, (unsigned int *)&sc->ds);
211 __put_user(env->regs[R_EDI], &sc->edi);
212 __put_user(env->regs[R_ESI], &sc->esi);
213 __put_user(env->regs[R_EBP], &sc->ebp);
214 __put_user(env->regs[R_ESP], &sc->esp);
215 __put_user(env->regs[R_EBX], &sc->ebx);
216 __put_user(env->regs[R_EDX], &sc->edx);
217 __put_user(env->regs[R_ECX], &sc->ecx);
218 __put_user(env->regs[R_EAX], &sc->eax);
219 __put_user(cs->exception_index, &sc->trapno);
220 __put_user(env->error_code, &sc->err);
221 __put_user(env->eip, &sc->eip);
222 __put_user(env->segs[R_CS].selector, (unsigned int *)&sc->cs);
223 __put_user(env->eflags, &sc->eflags);
224 __put_user(env->regs[R_ESP], &sc->esp_at_signal);
225 __put_user(env->segs[R_SS].selector, (unsigned int *)&sc->ss);
226
227 cpu_x86_fsave(env, fpstate_addr, 1);
228 fpstate->status = fpstate->sw;
229 magic = 0xffff;
230 __put_user(magic, &fpstate->magic);
231 __put_user(fpstate_addr, &sc->fpstate);
232
233 /* non-iBCS2 extensions.. */
234 __put_user(mask, &sc->oldmask);
235 __put_user(env->cr[2], &sc->cr2);
236 #else
237 __put_user(env->regs[R_EDI], &sc->rdi);
238 __put_user(env->regs[R_ESI], &sc->rsi);
239 __put_user(env->regs[R_EBP], &sc->rbp);
240 __put_user(env->regs[R_ESP], &sc->rsp);
241 __put_user(env->regs[R_EBX], &sc->rbx);
242 __put_user(env->regs[R_EDX], &sc->rdx);
243 __put_user(env->regs[R_ECX], &sc->rcx);
244 __put_user(env->regs[R_EAX], &sc->rax);
245
246 __put_user(env->regs[8], &sc->r8);
247 __put_user(env->regs[9], &sc->r9);
248 __put_user(env->regs[10], &sc->r10);
249 __put_user(env->regs[11], &sc->r11);
250 __put_user(env->regs[12], &sc->r12);
251 __put_user(env->regs[13], &sc->r13);
252 __put_user(env->regs[14], &sc->r14);
253 __put_user(env->regs[15], &sc->r15);
254
255 __put_user(cs->exception_index, &sc->trapno);
256 __put_user(env->error_code, &sc->err);
257 __put_user(env->eip, &sc->rip);
258
259 __put_user(env->eflags, &sc->eflags);
260 __put_user(env->segs[R_CS].selector, &sc->cs);
261 __put_user((uint16_t)0, &sc->gs);
262 __put_user((uint16_t)0, &sc->fs);
263 __put_user(env->segs[R_SS].selector, &sc->ss);
264
265 __put_user(mask, &sc->oldmask);
266 __put_user(env->cr[2], &sc->cr2);
267
268 /* fpstate_addr must be 16 byte aligned for fxsave */
269 assert(!(fpstate_addr & 0xf));
270
271 cpu_x86_fxsave(env, fpstate_addr);
272 __put_user(fpstate_addr, &sc->fpstate);
273 #endif
274 }
275
276 /*
277 * Determine which stack to use..
278 */
279
280 static inline abi_ulong
281 get_sigframe(struct target_sigaction *ka, CPUX86State *env, size_t frame_size)
282 {
283 unsigned long esp;
284
285 /* Default to using normal stack */
286 esp = get_sp_from_cpustate(env);
287 #ifdef TARGET_X86_64
288 esp -= 128; /* this is the redzone */
289 #endif
290
291 /* This is the X/Open sanctioned signal stack switching. */
292 if (ka->sa_flags & TARGET_SA_ONSTACK) {
293 esp = target_sigsp(esp, ka);
294 } else {
295 #ifndef TARGET_X86_64
296 /* This is the legacy signal stack switching. */
297 if ((env->segs[R_SS].selector & 0xffff) != __USER_DS &&
298 !(ka->sa_flags & TARGET_SA_RESTORER) &&
299 ka->sa_restorer) {
300 esp = (unsigned long) ka->sa_restorer;
301 }
302 #endif
303 }
304
305 #ifndef TARGET_X86_64
306 return (esp - frame_size) & -8ul;
307 #else
308 return ((esp - frame_size) & (~15ul)) - 8;
309 #endif
310 }
311
312 #ifndef TARGET_X86_64
313 static void install_sigtramp(void *tramp)
314 {
315 /* This is popl %eax ; movl $syscall,%eax ; int $0x80 */
316 __put_user(0xb858, (uint16_t *)(tramp + 0));
317 __put_user(TARGET_NR_sigreturn, (int32_t *)(tramp + 2));
318 __put_user(0x80cd, (uint16_t *)(tramp + 6));
319 }
320
321 static void install_rt_sigtramp(void *tramp)
322 {
323 /* This is movl $syscall,%eax ; int $0x80 */
324 __put_user(0xb8, (uint8_t *)(tramp + 0));
325 __put_user(TARGET_NR_rt_sigreturn, (int32_t *)(tramp + 1));
326 __put_user(0x80cd, (uint16_t *)(tramp + 5));
327 }
328
329 /* compare linux/arch/i386/kernel/signal.c:setup_frame() */
330 void setup_frame(int sig, struct target_sigaction *ka,
331 target_sigset_t *set, CPUX86State *env)
332 {
333 abi_ulong frame_addr;
334 struct sigframe *frame;
335 int i;
336
337 frame_addr = get_sigframe(ka, env, sizeof(*frame));
338 trace_user_setup_frame(env, frame_addr);
339
340 if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0))
341 goto give_sigsegv;
342
343 __put_user(sig, &frame->sig);
344
345 setup_sigcontext(&frame->sc, &frame->fpstate, env, set->sig[0],
346 frame_addr + offsetof(struct sigframe, fpstate));
347
348 for(i = 1; i < TARGET_NSIG_WORDS; i++) {
349 __put_user(set->sig[i], &frame->extramask[i - 1]);
350 }
351
352 /* Set up to return from userspace. If provided, use a stub
353 already in userspace. */
354 if (ka->sa_flags & TARGET_SA_RESTORER) {
355 __put_user(ka->sa_restorer, &frame->pretcode);
356 } else {
357 /* This is no longer used, but is retained for ABI compatibility. */
358 install_sigtramp(frame->retcode);
359 __put_user(default_sigreturn, &frame->pretcode);
360 }
361
362 /* Set up registers for signal handler */
363 env->regs[R_ESP] = frame_addr;
364 env->eip = ka->_sa_handler;
365
366 cpu_x86_load_seg(env, R_DS, __USER_DS);
367 cpu_x86_load_seg(env, R_ES, __USER_DS);
368 cpu_x86_load_seg(env, R_SS, __USER_DS);
369 cpu_x86_load_seg(env, R_CS, __USER_CS);
370 env->eflags &= ~TF_MASK;
371
372 unlock_user_struct(frame, frame_addr, 1);
373
374 return;
375
376 give_sigsegv:
377 force_sigsegv(sig);
378 }
379 #endif
380
381 /* compare linux/arch/x86/kernel/signal.c:setup_rt_frame() */
382 void setup_rt_frame(int sig, struct target_sigaction *ka,
383 target_siginfo_t *info,
384 target_sigset_t *set, CPUX86State *env)
385 {
386 abi_ulong frame_addr;
387 #ifndef TARGET_X86_64
388 abi_ulong addr;
389 #endif
390 struct rt_sigframe *frame;
391 int i;
392
393 frame_addr = get_sigframe(ka, env, sizeof(*frame));
394 trace_user_setup_rt_frame(env, frame_addr);
395
396 if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0))
397 goto give_sigsegv;
398
399 /* These fields are only in rt_sigframe on 32 bit */
400 #ifndef TARGET_X86_64
401 __put_user(sig, &frame->sig);
402 addr = frame_addr + offsetof(struct rt_sigframe, info);
403 __put_user(addr, &frame->pinfo);
404 addr = frame_addr + offsetof(struct rt_sigframe, uc);
405 __put_user(addr, &frame->puc);
406 #endif
407 if (ka->sa_flags & TARGET_SA_SIGINFO) {
408 tswap_siginfo(&frame->info, info);
409 }
410
411 /* Create the ucontext. */
412 __put_user(0, &frame->uc.tuc_flags);
413 __put_user(0, &frame->uc.tuc_link);
414 target_save_altstack(&frame->uc.tuc_stack, env);
415 setup_sigcontext(&frame->uc.tuc_mcontext, &frame->fpstate, env,
416 set->sig[0], frame_addr + offsetof(struct rt_sigframe, fpstate));
417
418 for(i = 0; i < TARGET_NSIG_WORDS; i++) {
419 __put_user(set->sig[i], &frame->uc.tuc_sigmask.sig[i]);
420 }
421
422 /* Set up to return from userspace. If provided, use a stub
423 already in userspace. */
424 if (ka->sa_flags & TARGET_SA_RESTORER) {
425 __put_user(ka->sa_restorer, &frame->pretcode);
426 } else {
427 #ifdef TARGET_X86_64
428 /* For x86_64, SA_RESTORER is required ABI. */
429 goto give_sigsegv;
430 #else
431 /* This is no longer used, but is retained for ABI compatibility. */
432 install_rt_sigtramp(frame->retcode);
433 __put_user(default_rt_sigreturn, &frame->pretcode);
434 #endif
435 }
436
437 /* Set up registers for signal handler */
438 env->regs[R_ESP] = frame_addr;
439 env->eip = ka->_sa_handler;
440
441 #ifndef TARGET_X86_64
442 env->regs[R_EAX] = sig;
443 env->regs[R_EDX] = frame_addr + offsetof(struct rt_sigframe, info);
444 env->regs[R_ECX] = frame_addr + offsetof(struct rt_sigframe, uc);
445 #else
446 env->regs[R_EAX] = 0;
447 env->regs[R_EDI] = sig;
448 env->regs[R_ESI] = frame_addr + offsetof(struct rt_sigframe, info);
449 env->regs[R_EDX] = frame_addr + offsetof(struct rt_sigframe, uc);
450 #endif
451
452 cpu_x86_load_seg(env, R_DS, __USER_DS);
453 cpu_x86_load_seg(env, R_ES, __USER_DS);
454 cpu_x86_load_seg(env, R_CS, __USER_CS);
455 cpu_x86_load_seg(env, R_SS, __USER_DS);
456 env->eflags &= ~TF_MASK;
457
458 unlock_user_struct(frame, frame_addr, 1);
459
460 return;
461
462 give_sigsegv:
463 force_sigsegv(sig);
464 }
465
466 static int
467 restore_sigcontext(CPUX86State *env, struct target_sigcontext *sc)
468 {
469 unsigned int err = 0;
470 abi_ulong fpstate_addr;
471 unsigned int tmpflags;
472
473 #ifndef TARGET_X86_64
474 cpu_x86_load_seg(env, R_GS, tswap16(sc->gs));
475 cpu_x86_load_seg(env, R_FS, tswap16(sc->fs));
476 cpu_x86_load_seg(env, R_ES, tswap16(sc->es));
477 cpu_x86_load_seg(env, R_DS, tswap16(sc->ds));
478
479 env->regs[R_EDI] = tswapl(sc->edi);
480 env->regs[R_ESI] = tswapl(sc->esi);
481 env->regs[R_EBP] = tswapl(sc->ebp);
482 env->regs[R_ESP] = tswapl(sc->esp);
483 env->regs[R_EBX] = tswapl(sc->ebx);
484 env->regs[R_EDX] = tswapl(sc->edx);
485 env->regs[R_ECX] = tswapl(sc->ecx);
486 env->regs[R_EAX] = tswapl(sc->eax);
487
488 env->eip = tswapl(sc->eip);
489 #else
490 env->regs[8] = tswapl(sc->r8);
491 env->regs[9] = tswapl(sc->r9);
492 env->regs[10] = tswapl(sc->r10);
493 env->regs[11] = tswapl(sc->r11);
494 env->regs[12] = tswapl(sc->r12);
495 env->regs[13] = tswapl(sc->r13);
496 env->regs[14] = tswapl(sc->r14);
497 env->regs[15] = tswapl(sc->r15);
498
499 env->regs[R_EDI] = tswapl(sc->rdi);
500 env->regs[R_ESI] = tswapl(sc->rsi);
501 env->regs[R_EBP] = tswapl(sc->rbp);
502 env->regs[R_EBX] = tswapl(sc->rbx);
503 env->regs[R_EDX] = tswapl(sc->rdx);
504 env->regs[R_EAX] = tswapl(sc->rax);
505 env->regs[R_ECX] = tswapl(sc->rcx);
506 env->regs[R_ESP] = tswapl(sc->rsp);
507
508 env->eip = tswapl(sc->rip);
509 #endif
510
511 cpu_x86_load_seg(env, R_CS, lduw_p(&sc->cs) | 3);
512 cpu_x86_load_seg(env, R_SS, lduw_p(&sc->ss) | 3);
513
514 tmpflags = tswapl(sc->eflags);
515 env->eflags = (env->eflags & ~0x40DD5) | (tmpflags & 0x40DD5);
516 // regs->orig_eax = -1; /* disable syscall checks */
517
518 fpstate_addr = tswapl(sc->fpstate);
519 if (fpstate_addr != 0) {
520 if (!access_ok(env_cpu(env), VERIFY_READ, fpstate_addr,
521 sizeof(struct target_fpstate))) {
522 goto badframe;
523 }
524 #ifndef TARGET_X86_64
525 cpu_x86_frstor(env, fpstate_addr, 1);
526 #else
527 cpu_x86_fxrstor(env, fpstate_addr);
528 #endif
529 }
530
531 return err;
532 badframe:
533 return 1;
534 }
535
536 /* Note: there is no sigreturn on x86_64, there is only rt_sigreturn */
537 #ifndef TARGET_X86_64
538 long do_sigreturn(CPUX86State *env)
539 {
540 struct sigframe *frame;
541 abi_ulong frame_addr = env->regs[R_ESP] - 8;
542 target_sigset_t target_set;
543 sigset_t set;
544 int i;
545
546 trace_user_do_sigreturn(env, frame_addr);
547 if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1))
548 goto badframe;
549 /* set blocked signals */
550 __get_user(target_set.sig[0], &frame->sc.oldmask);
551 for(i = 1; i < TARGET_NSIG_WORDS; i++) {
552 __get_user(target_set.sig[i], &frame->extramask[i - 1]);
553 }
554
555 target_to_host_sigset_internal(&set, &target_set);
556 set_sigmask(&set);
557
558 /* restore registers */
559 if (restore_sigcontext(env, &frame->sc))
560 goto badframe;
561 unlock_user_struct(frame, frame_addr, 0);
562 return -QEMU_ESIGRETURN;
563
564 badframe:
565 unlock_user_struct(frame, frame_addr, 0);
566 force_sig(TARGET_SIGSEGV);
567 return -QEMU_ESIGRETURN;
568 }
569 #endif
570
571 long do_rt_sigreturn(CPUX86State *env)
572 {
573 abi_ulong frame_addr;
574 struct rt_sigframe *frame;
575 sigset_t set;
576
577 frame_addr = env->regs[R_ESP] - sizeof(abi_ulong);
578 trace_user_do_rt_sigreturn(env, frame_addr);
579 if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1))
580 goto badframe;
581 target_to_host_sigset(&set, &frame->uc.tuc_sigmask);
582 set_sigmask(&set);
583
584 if (restore_sigcontext(env, &frame->uc.tuc_mcontext)) {
585 goto badframe;
586 }
587
588 target_restore_altstack(&frame->uc.tuc_stack, env);
589
590 unlock_user_struct(frame, frame_addr, 0);
591 return -QEMU_ESIGRETURN;
592
593 badframe:
594 unlock_user_struct(frame, frame_addr, 0);
595 force_sig(TARGET_SIGSEGV);
596 return -QEMU_ESIGRETURN;
597 }
598
599 #ifndef TARGET_X86_64
600 void setup_sigtramp(abi_ulong sigtramp_page)
601 {
602 uint16_t *tramp = lock_user(VERIFY_WRITE, sigtramp_page, 2 * 8, 0);
603 assert(tramp != NULL);
604
605 default_sigreturn = sigtramp_page;
606 install_sigtramp(tramp);
607
608 default_rt_sigreturn = sigtramp_page + 8;
609 install_rt_sigtramp(tramp + 8);
610
611 unlock_user(tramp, sigtramp_page, 2 * 8);
612 }
613 #endif
QEmu