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10#include <linux/cache.h>
11#include <linux/context_tracking.h>
12#include <linux/irqflags.h>
13#include <linux/sched.h>
14#include <linux/mm.h>
15#include <linux/personality.h>
16#include <linux/smp.h>
17#include <linux/kernel.h>
18#include <linux/signal.h>
19#include <linux/errno.h>
20#include <linux/wait.h>
21#include <linux/ptrace.h>
22#include <linux/unistd.h>
23#include <linux/compiler.h>
24#include <linux/syscalls.h>
25#include <linux/uaccess.h>
26#include <linux/tracehook.h>
27
28#include <asm/abi.h>
29#include <asm/asm.h>
30#include <linux/bitops.h>
31#include <asm/cacheflush.h>
32#include <asm/fpu.h>
33#include <asm/sim.h>
34#include <asm/ucontext.h>
35#include <asm/cpu-features.h>
36#include <asm/war.h>
37#include <asm/vdso.h>
38#include <asm/dsp.h>
39#include <asm/inst.h>
40
41#include "signal-common.h"
42
43static int (*save_fp_context)(struct sigcontext __user *sc);
44static int (*restore_fp_context)(struct sigcontext __user *sc);
45
46extern asmlinkage int _save_fp_context(struct sigcontext __user *sc);
47extern asmlinkage int _restore_fp_context(struct sigcontext __user *sc);
48
49extern asmlinkage int fpu_emulator_save_context(struct sigcontext __user *sc);
50extern asmlinkage int fpu_emulator_restore_context(struct sigcontext __user *sc);
51
52struct sigframe {
53 u32 sf_ass[4];
54 u32 sf_pad[2];
55 struct sigcontext sf_sc;
56 sigset_t sf_mask;
57};
58
59struct rt_sigframe {
60 u32 rs_ass[4];
61 u32 rs_pad[2];
62 struct siginfo rs_info;
63 struct ucontext rs_uc;
64};
65
66
67
68
69static int protected_save_fp_context(struct sigcontext __user *sc)
70{
71 int err;
72 while (1) {
73 lock_fpu_owner();
74 own_fpu_inatomic(1);
75 err = save_fp_context(sc);
76 unlock_fpu_owner();
77 if (likely(!err))
78 break;
79
80 err = __put_user(0, &sc->sc_fpregs[0]) |
81 __put_user(0, &sc->sc_fpregs[31]) |
82 __put_user(0, &sc->sc_fpc_csr);
83 if (err)
84 break;
85 }
86 return err;
87}
88
89static int protected_restore_fp_context(struct sigcontext __user *sc)
90{
91 int err, tmp __maybe_unused;
92 while (1) {
93 lock_fpu_owner();
94 own_fpu_inatomic(0);
95 err = restore_fp_context(sc);
96 unlock_fpu_owner();
97 if (likely(!err))
98 break;
99
100 err = __get_user(tmp, &sc->sc_fpregs[0]) |
101 __get_user(tmp, &sc->sc_fpregs[31]) |
102 __get_user(tmp, &sc->sc_fpc_csr);
103 if (err)
104 break;
105 }
106 return err;
107}
108
109int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
110{
111 int err = 0;
112 int i;
113 unsigned int used_math;
114
115 err |= __put_user(regs->cp0_epc, &sc->sc_pc);
116
117 err |= __put_user(0, &sc->sc_regs[0]);
118 for (i = 1; i < 32; i++)
119 err |= __put_user(regs->regs[i], &sc->sc_regs[i]);
120
121#ifdef CONFIG_CPU_HAS_SMARTMIPS
122 err |= __put_user(regs->acx, &sc->sc_acx);
123#endif
124 err |= __put_user(regs->hi, &sc->sc_mdhi);
125 err |= __put_user(regs->lo, &sc->sc_mdlo);
126 if (cpu_has_dsp) {
127 err |= __put_user(mfhi1(), &sc->sc_hi1);
128 err |= __put_user(mflo1(), &sc->sc_lo1);
129 err |= __put_user(mfhi2(), &sc->sc_hi2);
130 err |= __put_user(mflo2(), &sc->sc_lo2);
131 err |= __put_user(mfhi3(), &sc->sc_hi3);
132 err |= __put_user(mflo3(), &sc->sc_lo3);
133 err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
134 }
135
136 used_math = !!used_math();
137 err |= __put_user(used_math, &sc->sc_used_math);
138
139 if (used_math) {
140
141
142
143
144 err |= protected_save_fp_context(sc);
145 }
146 return err;
147}
148
149int fpcsr_pending(unsigned int __user *fpcsr)
150{
151 int err, sig = 0;
152 unsigned int csr, enabled;
153
154 err = __get_user(csr, fpcsr);
155 enabled = FPU_CSR_UNI_X | ((csr & FPU_CSR_ALL_E) << 5);
156
157
158
159
160 if (csr & enabled) {
161 csr &= ~enabled;
162 err |= __put_user(csr, fpcsr);
163 sig = SIGFPE;
164 }
165 return err ?: sig;
166}
167
168static int
169check_and_restore_fp_context(struct sigcontext __user *sc)
170{
171 int err, sig;
172
173 err = sig = fpcsr_pending(&sc->sc_fpc_csr);
174 if (err > 0)
175 err = 0;
176 err |= protected_restore_fp_context(sc);
177 return err ?: sig;
178}
179
180int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
181{
182 unsigned int used_math;
183 unsigned long treg;
184 int err = 0;
185 int i;
186
187
188 current_thread_info()->restart_block.fn = do_no_restart_syscall;
189
190 err |= __get_user(regs->cp0_epc, &sc->sc_pc);
191
192#ifdef CONFIG_CPU_HAS_SMARTMIPS
193 err |= __get_user(regs->acx, &sc->sc_acx);
194#endif
195 err |= __get_user(regs->hi, &sc->sc_mdhi);
196 err |= __get_user(regs->lo, &sc->sc_mdlo);
197 if (cpu_has_dsp) {
198 err |= __get_user(treg, &sc->sc_hi1); mthi1(treg);
199 err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
200 err |= __get_user(treg, &sc->sc_hi2); mthi2(treg);
201 err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
202 err |= __get_user(treg, &sc->sc_hi3); mthi3(treg);
203 err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
204 err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
205 }
206
207 for (i = 1; i < 32; i++)
208 err |= __get_user(regs->regs[i], &sc->sc_regs[i]);
209
210 err |= __get_user(used_math, &sc->sc_used_math);
211 conditional_used_math(used_math);
212
213 if (used_math) {
214
215 if (!err)
216 err = check_and_restore_fp_context(sc);
217 } else {
218
219 lose_fpu(0);
220 }
221
222 return err;
223}
224
225void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
226 size_t frame_size)
227{
228 unsigned long sp;
229
230
231 sp = regs->regs[29];
232
233
234
235
236
237
238 sp -= 32;
239
240
241 if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags (sp) == 0))
242 sp = current->sas_ss_sp + current->sas_ss_size;
243
244 return (void __user *)((sp - frame_size) & (ICACHE_REFILLS_WORKAROUND_WAR ? ~(cpu_icache_line_size()-1) : ALMASK));
245}
246
247
248
249
250
251#ifdef CONFIG_TRAD_SIGNALS
252SYSCALL_DEFINE1(sigsuspend, sigset_t __user *, uset)
253{
254 return sys_rt_sigsuspend(uset, sizeof(sigset_t));
255}
256#endif
257
258#ifdef CONFIG_TRAD_SIGNALS
259SYSCALL_DEFINE3(sigaction, int, sig, const struct sigaction __user *, act,
260 struct sigaction __user *, oact)
261{
262 struct k_sigaction new_ka, old_ka;
263 int ret;
264 int err = 0;
265
266 if (act) {
267 old_sigset_t mask;
268
269 if (!access_ok(VERIFY_READ, act, sizeof(*act)))
270 return -EFAULT;
271 err |= __get_user(new_ka.sa.sa_handler, &act->sa_handler);
272 err |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
273 err |= __get_user(mask, &act->sa_mask.sig[0]);
274 if (err)
275 return -EFAULT;
276
277 siginitset(&new_ka.sa.sa_mask, mask);
278 }
279
280 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
281
282 if (!ret && oact) {
283 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)))
284 return -EFAULT;
285 err |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
286 err |= __put_user(old_ka.sa.sa_handler, &oact->sa_handler);
287 err |= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig);
288 err |= __put_user(0, &oact->sa_mask.sig[1]);
289 err |= __put_user(0, &oact->sa_mask.sig[2]);
290 err |= __put_user(0, &oact->sa_mask.sig[3]);
291 if (err)
292 return -EFAULT;
293 }
294
295 return ret;
296}
297#endif
298
299#ifdef CONFIG_TRAD_SIGNALS
300asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs)
301{
302 struct sigframe __user *frame;
303 sigset_t blocked;
304 int sig;
305
306 frame = (struct sigframe __user *) regs.regs[29];
307 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
308 goto badframe;
309 if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked)))
310 goto badframe;
311
312 set_current_blocked(&blocked);
313
314 sig = restore_sigcontext(®s, &frame->sf_sc);
315 if (sig < 0)
316 goto badframe;
317 else if (sig)
318 force_sig(sig, current);
319
320
321
322
323 __asm__ __volatile__(
324 "move\t$29, %0\n\t"
325 "j\tsyscall_exit"
326 :
327 :"r" (®s));
328
329
330badframe:
331 force_sig(SIGSEGV, current);
332}
333#endif
334
335asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
336{
337 struct rt_sigframe __user *frame;
338 sigset_t set;
339 int sig;
340
341 frame = (struct rt_sigframe __user *) regs.regs[29];
342 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
343 goto badframe;
344 if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set)))
345 goto badframe;
346
347 set_current_blocked(&set);
348
349 sig = restore_sigcontext(®s, &frame->rs_uc.uc_mcontext);
350 if (sig < 0)
351 goto badframe;
352 else if (sig)
353 force_sig(sig, current);
354
355 if (restore_altstack(&frame->rs_uc.uc_stack))
356 goto badframe;
357
358
359
360
361 __asm__ __volatile__(
362 "move\t$29, %0\n\t"
363 "j\tsyscall_exit"
364 :
365 :"r" (®s));
366
367
368badframe:
369 force_sig(SIGSEGV, current);
370}
371
372#ifdef CONFIG_TRAD_SIGNALS
373static int setup_frame(void *sig_return, struct k_sigaction *ka,
374 struct pt_regs *regs, int signr, sigset_t *set)
375{
376 struct sigframe __user *frame;
377 int err = 0;
378
379 frame = get_sigframe(ka, regs, sizeof(*frame));
380 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
381 goto give_sigsegv;
382
383 err |= setup_sigcontext(regs, &frame->sf_sc);
384 err |= __copy_to_user(&frame->sf_mask, set, sizeof(*set));
385 if (err)
386 goto give_sigsegv;
387
388
389
390
391
392
393
394
395
396
397
398 regs->regs[ 4] = signr;
399 regs->regs[ 5] = 0;
400 regs->regs[ 6] = (unsigned long) &frame->sf_sc;
401 regs->regs[29] = (unsigned long) frame;
402 regs->regs[31] = (unsigned long) sig_return;
403 regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
404
405 DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
406 current->comm, current->pid,
407 frame, regs->cp0_epc, regs->regs[31]);
408 return 0;
409
410give_sigsegv:
411 force_sigsegv(signr, current);
412 return -EFAULT;
413}
414#endif
415
416static int setup_rt_frame(void *sig_return, struct k_sigaction *ka,
417 struct pt_regs *regs, int signr, sigset_t *set,
418 siginfo_t *info)
419{
420 struct rt_sigframe __user *frame;
421 int err = 0;
422
423 frame = get_sigframe(ka, regs, sizeof(*frame));
424 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
425 goto give_sigsegv;
426
427
428 err |= copy_siginfo_to_user(&frame->rs_info, info);
429
430
431 err |= __put_user(0, &frame->rs_uc.uc_flags);
432 err |= __put_user(NULL, &frame->rs_uc.uc_link);
433 err |= __save_altstack(&frame->rs_uc.uc_stack, regs->regs[29]);
434 err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
435 err |= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));
436
437 if (err)
438 goto give_sigsegv;
439
440
441
442
443
444
445
446
447
448
449
450 regs->regs[ 4] = signr;
451 regs->regs[ 5] = (unsigned long) &frame->rs_info;
452 regs->regs[ 6] = (unsigned long) &frame->rs_uc;
453 regs->regs[29] = (unsigned long) frame;
454 regs->regs[31] = (unsigned long) sig_return;
455 regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
456
457 DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
458 current->comm, current->pid,
459 frame, regs->cp0_epc, regs->regs[31]);
460
461 return 0;
462
463give_sigsegv:
464 force_sigsegv(signr, current);
465 return -EFAULT;
466}
467
468struct mips_abi mips_abi = {
469#ifdef CONFIG_TRAD_SIGNALS
470 .setup_frame = setup_frame,
471 .signal_return_offset = offsetof(struct mips_vdso, signal_trampoline),
472#endif
473 .setup_rt_frame = setup_rt_frame,
474 .rt_signal_return_offset =
475 offsetof(struct mips_vdso, rt_signal_trampoline),
476 .restart = __NR_restart_syscall
477};
478
479static void handle_signal(unsigned long sig, siginfo_t *info,
480 struct k_sigaction *ka, struct pt_regs *regs)
481{
482 sigset_t *oldset = sigmask_to_save();
483 int ret;
484 struct mips_abi *abi = current->thread.abi;
485#ifdef CONFIG_CPU_MICROMIPS
486 void *vdso;
487 unsigned int tmp = (unsigned int)current->mm->context.vdso;
488
489 set_isa16_mode(tmp);
490 vdso = (void *)tmp;
491#else
492 void *vdso = current->mm->context.vdso;
493#endif
494
495 if (regs->regs[0]) {
496 switch(regs->regs[2]) {
497 case ERESTART_RESTARTBLOCK:
498 case ERESTARTNOHAND:
499 regs->regs[2] = EINTR;
500 break;
501 case ERESTARTSYS:
502 if (!(ka->sa.sa_flags & SA_RESTART)) {
503 regs->regs[2] = EINTR;
504 break;
505 }
506
507 case ERESTARTNOINTR:
508 regs->regs[7] = regs->regs[26];
509 regs->regs[2] = regs->regs[0];
510 regs->cp0_epc -= 4;
511 }
512
513 regs->regs[0] = 0;
514 }
515
516 if (sig_uses_siginfo(ka))
517 ret = abi->setup_rt_frame(vdso + abi->rt_signal_return_offset,
518 ka, regs, sig, oldset, info);
519 else
520 ret = abi->setup_frame(vdso + abi->signal_return_offset,
521 ka, regs, sig, oldset);
522
523 if (ret)
524 return;
525
526 signal_delivered(sig, info, ka, regs, 0);
527}
528
529static void do_signal(struct pt_regs *regs)
530{
531 struct k_sigaction ka;
532 siginfo_t info;
533 int signr;
534
535 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
536 if (signr > 0) {
537
538 handle_signal(signr, &info, &ka, regs);
539 return;
540 }
541
542 if (regs->regs[0]) {
543 switch (regs->regs[2]) {
544 case ERESTARTNOHAND:
545 case ERESTARTSYS:
546 case ERESTARTNOINTR:
547 regs->regs[2] = regs->regs[0];
548 regs->regs[7] = regs->regs[26];
549 regs->cp0_epc -= 4;
550 break;
551
552 case ERESTART_RESTARTBLOCK:
553 regs->regs[2] = current->thread.abi->restart;
554 regs->regs[7] = regs->regs[26];
555 regs->cp0_epc -= 4;
556 break;
557 }
558 regs->regs[0] = 0;
559 }
560
561
562
563
564
565 restore_saved_sigmask();
566}
567
568
569
570
571
572asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
573 __u32 thread_info_flags)
574{
575 local_irq_enable();
576
577 user_exit();
578
579
580 if (thread_info_flags & _TIF_SIGPENDING)
581 do_signal(regs);
582
583 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
584 clear_thread_flag(TIF_NOTIFY_RESUME);
585 tracehook_notify_resume(regs);
586 }
587
588 user_enter();
589}
590
591#ifdef CONFIG_SMP
592static int smp_save_fp_context(struct sigcontext __user *sc)
593{
594 return raw_cpu_has_fpu
595 ? _save_fp_context(sc)
596 : fpu_emulator_save_context(sc);
597}
598
599static int smp_restore_fp_context(struct sigcontext __user *sc)
600{
601 return raw_cpu_has_fpu
602 ? _restore_fp_context(sc)
603 : fpu_emulator_restore_context(sc);
604}
605#endif
606
607static int signal_setup(void)
608{
609#ifdef CONFIG_SMP
610
611 save_fp_context = smp_save_fp_context;
612 restore_fp_context = smp_restore_fp_context;
613#else
614 if (cpu_has_fpu) {
615 save_fp_context = _save_fp_context;
616 restore_fp_context = _restore_fp_context;
617 } else {
618 save_fp_context = fpu_emulator_save_context;
619 restore_fp_context = fpu_emulator_restore_context;
620 }
621#endif
622
623 return 0;
624}
625
626arch_initcall(signal_setup);
627