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1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 1991, 1992 Linus Torvalds
7 * Copyright (C) 1994 - 2000 Ralf Baechle
8 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
9 */
10#include <linux/cache.h>
11#include <linux/irqflags.h>
12#include <linux/sched.h>
13#include <linux/mm.h>
14#include <linux/personality.h>
15#include <linux/smp.h>
16#include <linux/kernel.h>
17#include <linux/signal.h>
18#include <linux/errno.h>
19#include <linux/wait.h>
20#include <linux/ptrace.h>
21#include <linux/unistd.h>
22#include <linux/compiler.h>
23#include <linux/syscalls.h>
24#include <linux/uaccess.h>
25#include <linux/tracehook.h>
26
27#include <asm/abi.h>
28#include <asm/asm.h>
29#include <linux/bitops.h>
30#include <asm/cacheflush.h>
31#include <asm/fpu.h>
32#include <asm/sim.h>
33#include <asm/ucontext.h>
34#include <asm/cpu-features.h>
35#include <asm/war.h>
36#include <asm/vdso.h>
37
38#include "signal-common.h"
39
40static int (*save_fp_context)(struct sigcontext __user *sc);
41static int (*restore_fp_context)(struct sigcontext __user *sc);
42
43extern asmlinkage int _save_fp_context(struct sigcontext __user *sc);
44extern asmlinkage int _restore_fp_context(struct sigcontext __user *sc);
45
46extern asmlinkage int fpu_emulator_save_context(struct sigcontext __user *sc);
47extern asmlinkage int fpu_emulator_restore_context(struct sigcontext __user *sc);
48
49struct sigframe {
50 u32 sf_ass[4]; /* argument save space for o32 */
51 u32 sf_pad[2]; /* Was: signal trampoline */
52 struct sigcontext sf_sc;
53 sigset_t sf_mask;
54};
55
56struct rt_sigframe {
57 u32 rs_ass[4]; /* argument save space for o32 */
58 u32 rs_pad[2]; /* Was: signal trampoline */
59 struct siginfo rs_info;
60 struct ucontext rs_uc;
61};
62
63/*
64 * Helper routines
65 */
66static int protected_save_fp_context(struct sigcontext __user *sc)
67{
68 int err;
69 while (1) {
70 lock_fpu_owner();
71 own_fpu_inatomic(1);
72 err = save_fp_context(sc); /* this might fail */
73 unlock_fpu_owner();
74 if (likely(!err))
75 break;
76 /* touch the sigcontext and try again */
77 err = __put_user(0, &sc->sc_fpregs[0]) |
78 __put_user(0, &sc->sc_fpregs[31]) |
79 __put_user(0, &sc->sc_fpc_csr);
80 if (err)
81 break; /* really bad sigcontext */
82 }
83 return err;
84}
85
86static int protected_restore_fp_context(struct sigcontext __user *sc)
87{
88 int err, tmp __maybe_unused;
89 while (1) {
90 lock_fpu_owner();
91 own_fpu_inatomic(0);
92 err = restore_fp_context(sc); /* this might fail */
93 unlock_fpu_owner();
94 if (likely(!err))
95 break;
96 /* touch the sigcontext and try again */
97 err = __get_user(tmp, &sc->sc_fpregs[0]) |
98 __get_user(tmp, &sc->sc_fpregs[31]) |
99 __get_user(tmp, &sc->sc_fpc_csr);
100 if (err)
101 break; /* really bad sigcontext */
102 }
103 return err;
104}
105
106int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
107{
108 int err = 0;
109 int i;
110 unsigned int used_math;
111
112 err |= __put_user(regs->cp0_epc, &sc->sc_pc);
113
114 err |= __put_user(0, &sc->sc_regs[0]);
115 for (i = 1; i < 32; i++)
116 err |= __put_user(regs->regs[i], &sc->sc_regs[i]);
117
118#ifdef CONFIG_CPU_HAS_SMARTMIPS
119 err |= __put_user(regs->acx, &sc->sc_acx);
120#endif
121 err |= __put_user(regs->hi, &sc->sc_mdhi);
122 err |= __put_user(regs->lo, &sc->sc_mdlo);
123 if (cpu_has_dsp) {
124 err |= __put_user(mfhi1(), &sc->sc_hi1);
125 err |= __put_user(mflo1(), &sc->sc_lo1);
126 err |= __put_user(mfhi2(), &sc->sc_hi2);
127 err |= __put_user(mflo2(), &sc->sc_lo2);
128 err |= __put_user(mfhi3(), &sc->sc_hi3);
129 err |= __put_user(mflo3(), &sc->sc_lo3);
130 err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
131 }
132
133 used_math = !!used_math();
134 err |= __put_user(used_math, &sc->sc_used_math);
135
136 if (used_math) {
137 /*
138 * Save FPU state to signal context. Signal handler
139 * will "inherit" current FPU state.
140 */
141 err |= protected_save_fp_context(sc);
142 }
143 return err;
144}
145
146int fpcsr_pending(unsigned int __user *fpcsr)
147{
148 int err, sig = 0;
149 unsigned int csr, enabled;
150
151 err = __get_user(csr, fpcsr);
152 enabled = FPU_CSR_UNI_X | ((csr & FPU_CSR_ALL_E) << 5);
153 /*
154 * If the signal handler set some FPU exceptions, clear it and
155 * send SIGFPE.
156 */
157 if (csr & enabled) {
158 csr &= ~enabled;
159 err |= __put_user(csr, fpcsr);
160 sig = SIGFPE;
161 }
162 return err ?: sig;
163}
164
165static int
166check_and_restore_fp_context(struct sigcontext __user *sc)
167{
168 int err, sig;
169
170 err = sig = fpcsr_pending(&sc->sc_fpc_csr);
171 if (err > 0)
172 err = 0;
173 err |= protected_restore_fp_context(sc);
174 return err ?: sig;
175}
176
177int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
178{
179 unsigned int used_math;
180 unsigned long treg;
181 int err = 0;
182 int i;
183
184 /* Always make any pending restarted system calls return -EINTR */
185 current_thread_info()->restart_block.fn = do_no_restart_syscall;
186
187 err |= __get_user(regs->cp0_epc, &sc->sc_pc);
188
189#ifdef CONFIG_CPU_HAS_SMARTMIPS
190 err |= __get_user(regs->acx, &sc->sc_acx);
191#endif
192 err |= __get_user(regs->hi, &sc->sc_mdhi);
193 err |= __get_user(regs->lo, &sc->sc_mdlo);
194 if (cpu_has_dsp) {
195 err |= __get_user(treg, &sc->sc_hi1); mthi1(treg);
196 err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
197 err |= __get_user(treg, &sc->sc_hi2); mthi2(treg);
198 err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
199 err |= __get_user(treg, &sc->sc_hi3); mthi3(treg);
200 err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
201 err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
202 }
203
204 for (i = 1; i < 32; i++)
205 err |= __get_user(regs->regs[i], &sc->sc_regs[i]);
206
207 err |= __get_user(used_math, &sc->sc_used_math);
208 conditional_used_math(used_math);
209
210 if (used_math) {
211 /* restore fpu context if we have used it before */
212 if (!err)
213 err = check_and_restore_fp_context(sc);
214 } else {
215 /* signal handler may have used FPU. Give it up. */
216 lose_fpu(0);
217 }
218
219 return err;
220}
221
222void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
223 size_t frame_size)
224{
225 unsigned long sp;
226
227 /* Default to using normal stack */
228 sp = regs->regs[29];
229
230 /*
231 * FPU emulator may have it's own trampoline active just
232 * above the user stack, 16-bytes before the next lowest
233 * 16 byte boundary. Try to avoid trashing it.
234 */
235 sp -= 32;
236
237 /* This is the X/Open sanctioned signal stack switching. */
238 if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags (sp) == 0))
239 sp = current->sas_ss_sp + current->sas_ss_size;
240
241 return (void __user *)((sp - frame_size) & (ICACHE_REFILLS_WORKAROUND_WAR ? ~(cpu_icache_line_size()-1) : ALMASK));
242}
243
244/*
245 * Atomically swap in the new signal mask, and wait for a signal.
246 */
247
248#ifdef CONFIG_TRAD_SIGNALS
249asmlinkage int sys_sigsuspend(nabi_no_regargs struct pt_regs regs)
250{
251 sigset_t newset;
252 sigset_t __user *uset;
253
254 uset = (sigset_t __user *) regs.regs[4];
255 if (copy_from_user(&newset, uset, sizeof(sigset_t)))
256 return -EFAULT;
257 sigdelsetmask(&newset, ~_BLOCKABLE);
258
259 spin_lock_irq(¤t->sighand->siglock);
260 current->saved_sigmask = current->blocked;
261 current->blocked = newset;
262 recalc_sigpending();
263 spin_unlock_irq(¤t->sighand->siglock);
264
265 current->state = TASK_INTERRUPTIBLE;
266 schedule();
267 set_thread_flag(TIF_RESTORE_SIGMASK);
268 return -ERESTARTNOHAND;
269}
270#endif
271
272asmlinkage int sys_rt_sigsuspend(nabi_no_regargs struct pt_regs regs)
273{
274 sigset_t newset;
275 sigset_t __user *unewset;
276 size_t sigsetsize;
277
278 /* XXX Don't preclude handling different sized sigset_t's. */
279 sigsetsize = regs.regs[5];
280 if (sigsetsize != sizeof(sigset_t))
281 return -EINVAL;
282
283 unewset = (sigset_t __user *) regs.regs[4];
284 if (copy_from_user(&newset, unewset, sizeof(newset)))
285 return -EFAULT;
286 sigdelsetmask(&newset, ~_BLOCKABLE);
287
288 spin_lock_irq(¤t->sighand->siglock);
289 current->saved_sigmask = current->blocked;
290 current->blocked = newset;
291 recalc_sigpending();
292 spin_unlock_irq(¤t->sighand->siglock);
293
294 current->state = TASK_INTERRUPTIBLE;
295 schedule();
296 set_thread_flag(TIF_RESTORE_SIGMASK);
297 return -ERESTARTNOHAND;
298}
299
300#ifdef CONFIG_TRAD_SIGNALS
301SYSCALL_DEFINE3(sigaction, int, sig, const struct sigaction __user *, act,
302 struct sigaction __user *, oact)
303{
304 struct k_sigaction new_ka, old_ka;
305 int ret;
306 int err = 0;
307
308 if (act) {
309 old_sigset_t mask;
310
311 if (!access_ok(VERIFY_READ, act, sizeof(*act)))
312 return -EFAULT;
313 err |= __get_user(new_ka.sa.sa_handler, &act->sa_handler);
314 err |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
315 err |= __get_user(mask, &act->sa_mask.sig[0]);
316 if (err)
317 return -EFAULT;
318
319 siginitset(&new_ka.sa.sa_mask, mask);
320 }
321
322 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
323
324 if (!ret && oact) {
325 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)))
326 return -EFAULT;
327 err |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
328 err |= __put_user(old_ka.sa.sa_handler, &oact->sa_handler);
329 err |= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig);
330 err |= __put_user(0, &oact->sa_mask.sig[1]);
331 err |= __put_user(0, &oact->sa_mask.sig[2]);
332 err |= __put_user(0, &oact->sa_mask.sig[3]);
333 if (err)
334 return -EFAULT;
335 }
336
337 return ret;
338}
339#endif
340
341asmlinkage int sys_sigaltstack(nabi_no_regargs struct pt_regs regs)
342{
343 const stack_t __user *uss = (const stack_t __user *) regs.regs[4];
344 stack_t __user *uoss = (stack_t __user *) regs.regs[5];
345 unsigned long usp = regs.regs[29];
346
347 return do_sigaltstack(uss, uoss, usp);
348}
349
350#ifdef CONFIG_TRAD_SIGNALS
351asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs)
352{
353 struct sigframe __user *frame;
354 sigset_t blocked;
355 int sig;
356
357 frame = (struct sigframe __user *) regs.regs[29];
358 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
359 goto badframe;
360 if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked)))
361 goto badframe;
362
363 sigdelsetmask(&blocked, ~_BLOCKABLE);
364 spin_lock_irq(¤t->sighand->siglock);
365 current->blocked = blocked;
366 recalc_sigpending();
367 spin_unlock_irq(¤t->sighand->siglock);
368
369 sig = restore_sigcontext(®s, &frame->sf_sc);
370 if (sig < 0)
371 goto badframe;
372 else if (sig)
373 force_sig(sig, current);
374
375 /*
376 * Don't let your children do this ...
377 */
378 __asm__ __volatile__(
379 "move\t$29, %0\n\t"
380 "j\tsyscall_exit"
381 :/* no outputs */
382 :"r" (®s));
383 /* Unreached */
384
385badframe:
386 force_sig(SIGSEGV, current);
387}
388#endif /* CONFIG_TRAD_SIGNALS */
389
390asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
391{
392 struct rt_sigframe __user *frame;
393 sigset_t set;
394 int sig;
395
396 frame = (struct rt_sigframe __user *) regs.regs[29];
397 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
398 goto badframe;
399 if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set)))
400 goto badframe;
401
402 sigdelsetmask(&set, ~_BLOCKABLE);
403 spin_lock_irq(¤t->sighand->siglock);
404 current->blocked = set;
405 recalc_sigpending();
406 spin_unlock_irq(¤t->sighand->siglock);
407
408 sig = restore_sigcontext(®s, &frame->rs_uc.uc_mcontext);
409 if (sig < 0)
410 goto badframe;
411 else if (sig)
412 force_sig(sig, current);
413
414 /* It is more difficult to avoid calling this function than to
415 call it and ignore errors. */
416 do_sigaltstack(&frame->rs_uc.uc_stack, NULL, regs.regs[29]);
417
418 /*
419 * Don't let your children do this ...
420 */
421 __asm__ __volatile__(
422 "move\t$29, %0\n\t"
423 "j\tsyscall_exit"
424 :/* no outputs */
425 :"r" (®s));
426 /* Unreached */
427
428badframe:
429 force_sig(SIGSEGV, current);
430}
431
432#ifdef CONFIG_TRAD_SIGNALS
433static int setup_frame(void *sig_return, struct k_sigaction *ka,
434 struct pt_regs *regs, int signr, sigset_t *set)
435{
436 struct sigframe __user *frame;
437 int err = 0;
438
439 frame = get_sigframe(ka, regs, sizeof(*frame));
440 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
441 goto give_sigsegv;
442
443 err |= setup_sigcontext(regs, &frame->sf_sc);
444 err |= __copy_to_user(&frame->sf_mask, set, sizeof(*set));
445 if (err)
446 goto give_sigsegv;
447
448 /*
449 * Arguments to signal handler:
450 *
451 * a0 = signal number
452 * a1 = 0 (should be cause)
453 * a2 = pointer to struct sigcontext
454 *
455 * $25 and c0_epc point to the signal handler, $29 points to the
456 * struct sigframe.
457 */
458 regs->regs[ 4] = signr;
459 regs->regs[ 5] = 0;
460 regs->regs[ 6] = (unsigned long) &frame->sf_sc;
461 regs->regs[29] = (unsigned long) frame;
462 regs->regs[31] = (unsigned long) sig_return;
463 regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
464
465 DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
466 current->comm, current->pid,
467 frame, regs->cp0_epc, regs->regs[31]);
468 return 0;
469
470give_sigsegv:
471 force_sigsegv(signr, current);
472 return -EFAULT;
473}
474#endif
475
476static int setup_rt_frame(void *sig_return, struct k_sigaction *ka,
477 struct pt_regs *regs, int signr, sigset_t *set,
478 siginfo_t *info)
479{
480 struct rt_sigframe __user *frame;
481 int err = 0;
482
483 frame = get_sigframe(ka, regs, sizeof(*frame));
484 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
485 goto give_sigsegv;
486
487 /* Create siginfo. */
488 err |= copy_siginfo_to_user(&frame->rs_info, info);
489
490 /* Create the ucontext. */
491 err |= __put_user(0, &frame->rs_uc.uc_flags);
492 err |= __put_user(NULL, &frame->rs_uc.uc_link);
493 err |= __put_user((void __user *)current->sas_ss_sp,
494 &frame->rs_uc.uc_stack.ss_sp);
495 err |= __put_user(sas_ss_flags(regs->regs[29]),
496 &frame->rs_uc.uc_stack.ss_flags);
497 err |= __put_user(current->sas_ss_size,
498 &frame->rs_uc.uc_stack.ss_size);
499 err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
500 err |= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));
501
502 if (err)
503 goto give_sigsegv;
504
505 /*
506 * Arguments to signal handler:
507 *
508 * a0 = signal number
509 * a1 = 0 (should be cause)
510 * a2 = pointer to ucontext
511 *
512 * $25 and c0_epc point to the signal handler, $29 points to
513 * the struct rt_sigframe.
514 */
515 regs->regs[ 4] = signr;
516 regs->regs[ 5] = (unsigned long) &frame->rs_info;
517 regs->regs[ 6] = (unsigned long) &frame->rs_uc;
518 regs->regs[29] = (unsigned long) frame;
519 regs->regs[31] = (unsigned long) sig_return;
520 regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
521
522 DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
523 current->comm, current->pid,
524 frame, regs->cp0_epc, regs->regs[31]);
525
526 return 0;
527
528give_sigsegv:
529 force_sigsegv(signr, current);
530 return -EFAULT;
531}
532
533struct mips_abi mips_abi = {
534#ifdef CONFIG_TRAD_SIGNALS
535 .setup_frame = setup_frame,
536 .signal_return_offset = offsetof(struct mips_vdso, signal_trampoline),
537#endif
538 .setup_rt_frame = setup_rt_frame,
539 .rt_signal_return_offset =
540 offsetof(struct mips_vdso, rt_signal_trampoline),
541 .restart = __NR_restart_syscall
542};
543
544static int handle_signal(unsigned long sig, siginfo_t *info,
545 struct k_sigaction *ka, sigset_t *oldset, struct pt_regs *regs)
546{
547 int ret;
548 struct mips_abi *abi = current->thread.abi;
549 void *vdso = current->mm->context.vdso;
550
551 if (regs->regs[0]) {
552 switch(regs->regs[2]) {
553 case ERESTART_RESTARTBLOCK:
554 case ERESTARTNOHAND:
555 regs->regs[2] = EINTR;
556 break;
557 case ERESTARTSYS:
558 if (!(ka->sa.sa_flags & SA_RESTART)) {
559 regs->regs[2] = EINTR;
560 break;
561 }
562 /* fallthrough */
563 case ERESTARTNOINTR:
564 regs->regs[7] = regs->regs[26];
565 regs->regs[2] = regs->regs[0];
566 regs->cp0_epc -= 4;
567 }
568
569 regs->regs[0] = 0; /* Don't deal with this again. */
570 }
571
572 if (sig_uses_siginfo(ka))
573 ret = abi->setup_rt_frame(vdso + abi->rt_signal_return_offset,
574 ka, regs, sig, oldset, info);
575 else
576 ret = abi->setup_frame(vdso + abi->signal_return_offset,
577 ka, regs, sig, oldset);
578
579 if (ret)
580 return ret;
581
582 spin_lock_irq(¤t->sighand->siglock);
583 sigorsets(¤t->blocked, ¤t->blocked, &ka->sa.sa_mask);
584 if (!(ka->sa.sa_flags & SA_NODEFER))
585 sigaddset(¤t->blocked, sig);
586 recalc_sigpending();
587 spin_unlock_irq(¤t->sighand->siglock);
588
589 return ret;
590}
591
592static void do_signal(struct pt_regs *regs)
593{
594 struct k_sigaction ka;
595 sigset_t *oldset;
596 siginfo_t info;
597 int signr;
598
599 /*
600 * We want the common case to go fast, which is why we may in certain
601 * cases get here from kernel mode. Just return without doing anything
602 * if so.
603 */
604 if (!user_mode(regs))
605 return;
606
607 if (test_thread_flag(TIF_RESTORE_SIGMASK))
608 oldset = ¤t->saved_sigmask;
609 else
610 oldset = ¤t->blocked;
611
612 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
613 if (signr > 0) {
614 /* Whee! Actually deliver the signal. */
615 if (handle_signal(signr, &info, &ka, oldset, regs) == 0) {
616 /*
617 * A signal was successfully delivered; the saved
618 * sigmask will have been stored in the signal frame,
619 * and will be restored by sigreturn, so we can simply
620 * clear the TIF_RESTORE_SIGMASK flag.
621 */
622 if (test_thread_flag(TIF_RESTORE_SIGMASK))
623 clear_thread_flag(TIF_RESTORE_SIGMASK);
624 }
625
626 return;
627 }
628
629 if (regs->regs[0]) {
630 if (regs->regs[2] == ERESTARTNOHAND ||
631 regs->regs[2] == ERESTARTSYS ||
632 regs->regs[2] == ERESTARTNOINTR) {
633 regs->regs[2] = regs->regs[0];
634 regs->regs[7] = regs->regs[26];
635 regs->cp0_epc -= 4;
636 }
637 if (regs->regs[2] == ERESTART_RESTARTBLOCK) {
638 regs->regs[2] = current->thread.abi->restart;
639 regs->regs[7] = regs->regs[26];
640 regs->cp0_epc -= 4;
641 }
642 regs->regs[0] = 0; /* Don't deal with this again. */
643 }
644
645 /*
646 * If there's no signal to deliver, we just put the saved sigmask
647 * back
648 */
649 if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
650 clear_thread_flag(TIF_RESTORE_SIGMASK);
651 sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL);
652 }
653}
654
655/*
656 * notification of userspace execution resumption
657 * - triggered by the TIF_WORK_MASK flags
658 */
659asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
660 __u32 thread_info_flags)
661{
662 local_irq_enable();
663
664 /* deal with pending signal delivery */
665 if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
666 do_signal(regs);
667
668 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
669 clear_thread_flag(TIF_NOTIFY_RESUME);
670 tracehook_notify_resume(regs);
671 if (current->replacement_session_keyring)
672 key_replace_session_keyring();
673 }
674}
675
676#ifdef CONFIG_SMP
677static int smp_save_fp_context(struct sigcontext __user *sc)
678{
679 return raw_cpu_has_fpu
680 ? _save_fp_context(sc)
681 : fpu_emulator_save_context(sc);
682}
683
684static int smp_restore_fp_context(struct sigcontext __user *sc)
685{
686 return raw_cpu_has_fpu
687 ? _restore_fp_context(sc)
688 : fpu_emulator_restore_context(sc);
689}
690#endif
691
692static int signal_setup(void)
693{
694#ifdef CONFIG_SMP
695 /* For now just do the cpu_has_fpu check when the functions are invoked */
696 save_fp_context = smp_save_fp_context;
697 restore_fp_context = smp_restore_fp_context;
698#else
699 if (cpu_has_fpu) {
700 save_fp_context = _save_fp_context;
701 restore_fp_context = _restore_fp_context;
702 } else {
703 save_fp_context = fpu_emulator_save_context;
704 restore_fp_context = fpu_emulator_restore_context;
705 }
706#endif
707
708 return 0;
709}
710
711arch_initcall(signal_setup);
1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 1991, 1992 Linus Torvalds
7 * Copyright (C) 1994 - 2000 Ralf Baechle
8 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
9 * Copyright (C) 2014, Imagination Technologies Ltd.
10 */
11#include <linux/cache.h>
12#include <linux/context_tracking.h>
13#include <linux/irqflags.h>
14#include <linux/sched.h>
15#include <linux/mm.h>
16#include <linux/personality.h>
17#include <linux/smp.h>
18#include <linux/kernel.h>
19#include <linux/signal.h>
20#include <linux/errno.h>
21#include <linux/wait.h>
22#include <linux/ptrace.h>
23#include <linux/unistd.h>
24#include <linux/compiler.h>
25#include <linux/syscalls.h>
26#include <linux/uaccess.h>
27#include <linux/tracehook.h>
28
29#include <asm/abi.h>
30#include <asm/asm.h>
31#include <linux/bitops.h>
32#include <asm/cacheflush.h>
33#include <asm/fpu.h>
34#include <asm/msa.h>
35#include <asm/sim.h>
36#include <asm/ucontext.h>
37#include <asm/cpu-features.h>
38#include <asm/war.h>
39#include <asm/vdso.h>
40#include <asm/dsp.h>
41#include <asm/inst.h>
42
43#include "signal-common.h"
44
45static int (*save_fp_context)(struct sigcontext __user *sc);
46static int (*restore_fp_context)(struct sigcontext __user *sc);
47
48extern asmlinkage int _save_fp_context(struct sigcontext __user *sc);
49extern asmlinkage int _restore_fp_context(struct sigcontext __user *sc);
50
51extern asmlinkage int _save_msa_context(struct sigcontext __user *sc);
52extern asmlinkage int _restore_msa_context(struct sigcontext __user *sc);
53
54struct sigframe {
55 u32 sf_ass[4]; /* argument save space for o32 */
56 u32 sf_pad[2]; /* Was: signal trampoline */
57 struct sigcontext sf_sc;
58 sigset_t sf_mask;
59};
60
61struct rt_sigframe {
62 u32 rs_ass[4]; /* argument save space for o32 */
63 u32 rs_pad[2]; /* Was: signal trampoline */
64 struct siginfo rs_info;
65 struct ucontext rs_uc;
66};
67
68/*
69 * Thread saved context copy to/from a signal context presumed to be on the
70 * user stack, and therefore accessed with appropriate macros from uaccess.h.
71 */
72static int copy_fp_to_sigcontext(struct sigcontext __user *sc)
73{
74 int i;
75 int err = 0;
76
77 for (i = 0; i < NUM_FPU_REGS; i++) {
78 err |=
79 __put_user(get_fpr64(¤t->thread.fpu.fpr[i], 0),
80 &sc->sc_fpregs[i]);
81 }
82 err |= __put_user(current->thread.fpu.fcr31, &sc->sc_fpc_csr);
83
84 return err;
85}
86
87static int copy_fp_from_sigcontext(struct sigcontext __user *sc)
88{
89 int i;
90 int err = 0;
91 u64 fpr_val;
92
93 for (i = 0; i < NUM_FPU_REGS; i++) {
94 err |= __get_user(fpr_val, &sc->sc_fpregs[i]);
95 set_fpr64(¤t->thread.fpu.fpr[i], 0, fpr_val);
96 }
97 err |= __get_user(current->thread.fpu.fcr31, &sc->sc_fpc_csr);
98
99 return err;
100}
101
102/*
103 * These functions will save only the upper 64 bits of the vector registers,
104 * since the lower 64 bits have already been saved as the scalar FP context.
105 */
106static int copy_msa_to_sigcontext(struct sigcontext __user *sc)
107{
108 int i;
109 int err = 0;
110
111 for (i = 0; i < NUM_FPU_REGS; i++) {
112 err |=
113 __put_user(get_fpr64(¤t->thread.fpu.fpr[i], 1),
114 &sc->sc_msaregs[i]);
115 }
116 err |= __put_user(current->thread.fpu.msacsr, &sc->sc_msa_csr);
117
118 return err;
119}
120
121static int copy_msa_from_sigcontext(struct sigcontext __user *sc)
122{
123 int i;
124 int err = 0;
125 u64 val;
126
127 for (i = 0; i < NUM_FPU_REGS; i++) {
128 err |= __get_user(val, &sc->sc_msaregs[i]);
129 set_fpr64(¤t->thread.fpu.fpr[i], 1, val);
130 }
131 err |= __get_user(current->thread.fpu.msacsr, &sc->sc_msa_csr);
132
133 return err;
134}
135
136/*
137 * Helper routines
138 */
139static int protected_save_fp_context(struct sigcontext __user *sc,
140 unsigned used_math)
141{
142 int err;
143 bool save_msa = cpu_has_msa && (used_math & USEDMATH_MSA);
144#ifndef CONFIG_EVA
145 while (1) {
146 lock_fpu_owner();
147 if (is_fpu_owner()) {
148 err = save_fp_context(sc);
149 if (save_msa && !err)
150 err = _save_msa_context(sc);
151 unlock_fpu_owner();
152 } else {
153 unlock_fpu_owner();
154 err = copy_fp_to_sigcontext(sc);
155 if (save_msa && !err)
156 err = copy_msa_to_sigcontext(sc);
157 }
158 if (likely(!err))
159 break;
160 /* touch the sigcontext and try again */
161 err = __put_user(0, &sc->sc_fpregs[0]) |
162 __put_user(0, &sc->sc_fpregs[31]) |
163 __put_user(0, &sc->sc_fpc_csr);
164 if (err)
165 break; /* really bad sigcontext */
166 }
167#else
168 /*
169 * EVA does not have FPU EVA instructions so saving fpu context directly
170 * does not work.
171 */
172 disable_msa();
173 lose_fpu(1);
174 err = save_fp_context(sc); /* this might fail */
175 if (save_msa && !err)
176 err = copy_msa_to_sigcontext(sc);
177#endif
178 return err;
179}
180
181static int protected_restore_fp_context(struct sigcontext __user *sc,
182 unsigned used_math)
183{
184 int err, tmp __maybe_unused;
185 bool restore_msa = cpu_has_msa && (used_math & USEDMATH_MSA);
186#ifndef CONFIG_EVA
187 while (1) {
188 lock_fpu_owner();
189 if (is_fpu_owner()) {
190 err = restore_fp_context(sc);
191 if (restore_msa && !err) {
192 enable_msa();
193 err = _restore_msa_context(sc);
194 } else {
195 /* signal handler may have used MSA */
196 disable_msa();
197 }
198 unlock_fpu_owner();
199 } else {
200 unlock_fpu_owner();
201 err = copy_fp_from_sigcontext(sc);
202 if (!err && (used_math & USEDMATH_MSA))
203 err = copy_msa_from_sigcontext(sc);
204 }
205 if (likely(!err))
206 break;
207 /* touch the sigcontext and try again */
208 err = __get_user(tmp, &sc->sc_fpregs[0]) |
209 __get_user(tmp, &sc->sc_fpregs[31]) |
210 __get_user(tmp, &sc->sc_fpc_csr);
211 if (err)
212 break; /* really bad sigcontext */
213 }
214#else
215 /*
216 * EVA does not have FPU EVA instructions so restoring fpu context
217 * directly does not work.
218 */
219 enable_msa();
220 lose_fpu(0);
221 err = restore_fp_context(sc); /* this might fail */
222 if (restore_msa && !err)
223 err = copy_msa_from_sigcontext(sc);
224#endif
225 return err;
226}
227
228int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
229{
230 int err = 0;
231 int i;
232 unsigned int used_math;
233
234 err |= __put_user(regs->cp0_epc, &sc->sc_pc);
235
236 err |= __put_user(0, &sc->sc_regs[0]);
237 for (i = 1; i < 32; i++)
238 err |= __put_user(regs->regs[i], &sc->sc_regs[i]);
239
240#ifdef CONFIG_CPU_HAS_SMARTMIPS
241 err |= __put_user(regs->acx, &sc->sc_acx);
242#endif
243 err |= __put_user(regs->hi, &sc->sc_mdhi);
244 err |= __put_user(regs->lo, &sc->sc_mdlo);
245 if (cpu_has_dsp) {
246 err |= __put_user(mfhi1(), &sc->sc_hi1);
247 err |= __put_user(mflo1(), &sc->sc_lo1);
248 err |= __put_user(mfhi2(), &sc->sc_hi2);
249 err |= __put_user(mflo2(), &sc->sc_lo2);
250 err |= __put_user(mfhi3(), &sc->sc_hi3);
251 err |= __put_user(mflo3(), &sc->sc_lo3);
252 err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
253 }
254
255 used_math = used_math() ? USEDMATH_FP : 0;
256 used_math |= thread_msa_context_live() ? USEDMATH_MSA : 0;
257 err |= __put_user(used_math, &sc->sc_used_math);
258
259 if (used_math) {
260 /*
261 * Save FPU state to signal context. Signal handler
262 * will "inherit" current FPU state.
263 */
264 err |= protected_save_fp_context(sc, used_math);
265 }
266 return err;
267}
268
269int fpcsr_pending(unsigned int __user *fpcsr)
270{
271 int err, sig = 0;
272 unsigned int csr, enabled;
273
274 err = __get_user(csr, fpcsr);
275 enabled = FPU_CSR_UNI_X | ((csr & FPU_CSR_ALL_E) << 5);
276 /*
277 * If the signal handler set some FPU exceptions, clear it and
278 * send SIGFPE.
279 */
280 if (csr & enabled) {
281 csr &= ~enabled;
282 err |= __put_user(csr, fpcsr);
283 sig = SIGFPE;
284 }
285 return err ?: sig;
286}
287
288static int
289check_and_restore_fp_context(struct sigcontext __user *sc, unsigned used_math)
290{
291 int err, sig;
292
293 err = sig = fpcsr_pending(&sc->sc_fpc_csr);
294 if (err > 0)
295 err = 0;
296 err |= protected_restore_fp_context(sc, used_math);
297 return err ?: sig;
298}
299
300int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
301{
302 unsigned int used_math;
303 unsigned long treg;
304 int err = 0;
305 int i;
306
307 /* Always make any pending restarted system calls return -EINTR */
308 current_thread_info()->restart_block.fn = do_no_restart_syscall;
309
310 err |= __get_user(regs->cp0_epc, &sc->sc_pc);
311
312#ifdef CONFIG_CPU_HAS_SMARTMIPS
313 err |= __get_user(regs->acx, &sc->sc_acx);
314#endif
315 err |= __get_user(regs->hi, &sc->sc_mdhi);
316 err |= __get_user(regs->lo, &sc->sc_mdlo);
317 if (cpu_has_dsp) {
318 err |= __get_user(treg, &sc->sc_hi1); mthi1(treg);
319 err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
320 err |= __get_user(treg, &sc->sc_hi2); mthi2(treg);
321 err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
322 err |= __get_user(treg, &sc->sc_hi3); mthi3(treg);
323 err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
324 err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
325 }
326
327 for (i = 1; i < 32; i++)
328 err |= __get_user(regs->regs[i], &sc->sc_regs[i]);
329
330 err |= __get_user(used_math, &sc->sc_used_math);
331 conditional_used_math(used_math);
332
333 if (used_math) {
334 /* restore fpu context if we have used it before */
335 if (!err)
336 err = check_and_restore_fp_context(sc, used_math);
337 } else {
338 /* signal handler may have used FPU or MSA. Disable them. */
339 disable_msa();
340 lose_fpu(0);
341 }
342
343 return err;
344}
345
346void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
347 size_t frame_size)
348{
349 unsigned long sp;
350
351 /* Default to using normal stack */
352 sp = regs->regs[29];
353
354 /*
355 * FPU emulator may have it's own trampoline active just
356 * above the user stack, 16-bytes before the next lowest
357 * 16 byte boundary. Try to avoid trashing it.
358 */
359 sp -= 32;
360
361 /* This is the X/Open sanctioned signal stack switching. */
362 if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags (sp) == 0))
363 sp = current->sas_ss_sp + current->sas_ss_size;
364
365 return (void __user *)((sp - frame_size) & (ICACHE_REFILLS_WORKAROUND_WAR ? ~(cpu_icache_line_size()-1) : ALMASK));
366}
367
368/*
369 * Atomically swap in the new signal mask, and wait for a signal.
370 */
371
372#ifdef CONFIG_TRAD_SIGNALS
373SYSCALL_DEFINE1(sigsuspend, sigset_t __user *, uset)
374{
375 return sys_rt_sigsuspend(uset, sizeof(sigset_t));
376}
377#endif
378
379#ifdef CONFIG_TRAD_SIGNALS
380SYSCALL_DEFINE3(sigaction, int, sig, const struct sigaction __user *, act,
381 struct sigaction __user *, oact)
382{
383 struct k_sigaction new_ka, old_ka;
384 int ret;
385 int err = 0;
386
387 if (act) {
388 old_sigset_t mask;
389
390 if (!access_ok(VERIFY_READ, act, sizeof(*act)))
391 return -EFAULT;
392 err |= __get_user(new_ka.sa.sa_handler, &act->sa_handler);
393 err |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
394 err |= __get_user(mask, &act->sa_mask.sig[0]);
395 if (err)
396 return -EFAULT;
397
398 siginitset(&new_ka.sa.sa_mask, mask);
399 }
400
401 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
402
403 if (!ret && oact) {
404 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)))
405 return -EFAULT;
406 err |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
407 err |= __put_user(old_ka.sa.sa_handler, &oact->sa_handler);
408 err |= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig);
409 err |= __put_user(0, &oact->sa_mask.sig[1]);
410 err |= __put_user(0, &oact->sa_mask.sig[2]);
411 err |= __put_user(0, &oact->sa_mask.sig[3]);
412 if (err)
413 return -EFAULT;
414 }
415
416 return ret;
417}
418#endif
419
420#ifdef CONFIG_TRAD_SIGNALS
421asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs)
422{
423 struct sigframe __user *frame;
424 sigset_t blocked;
425 int sig;
426
427 frame = (struct sigframe __user *) regs.regs[29];
428 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
429 goto badframe;
430 if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked)))
431 goto badframe;
432
433 set_current_blocked(&blocked);
434
435 sig = restore_sigcontext(®s, &frame->sf_sc);
436 if (sig < 0)
437 goto badframe;
438 else if (sig)
439 force_sig(sig, current);
440
441 /*
442 * Don't let your children do this ...
443 */
444 __asm__ __volatile__(
445 "move\t$29, %0\n\t"
446 "j\tsyscall_exit"
447 :/* no outputs */
448 :"r" (®s));
449 /* Unreached */
450
451badframe:
452 force_sig(SIGSEGV, current);
453}
454#endif /* CONFIG_TRAD_SIGNALS */
455
456asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
457{
458 struct rt_sigframe __user *frame;
459 sigset_t set;
460 int sig;
461
462 frame = (struct rt_sigframe __user *) regs.regs[29];
463 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
464 goto badframe;
465 if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set)))
466 goto badframe;
467
468 set_current_blocked(&set);
469
470 sig = restore_sigcontext(®s, &frame->rs_uc.uc_mcontext);
471 if (sig < 0)
472 goto badframe;
473 else if (sig)
474 force_sig(sig, current);
475
476 if (restore_altstack(&frame->rs_uc.uc_stack))
477 goto badframe;
478
479 /*
480 * Don't let your children do this ...
481 */
482 __asm__ __volatile__(
483 "move\t$29, %0\n\t"
484 "j\tsyscall_exit"
485 :/* no outputs */
486 :"r" (®s));
487 /* Unreached */
488
489badframe:
490 force_sig(SIGSEGV, current);
491}
492
493#ifdef CONFIG_TRAD_SIGNALS
494static int setup_frame(void *sig_return, struct k_sigaction *ka,
495 struct pt_regs *regs, int signr, sigset_t *set)
496{
497 struct sigframe __user *frame;
498 int err = 0;
499
500 frame = get_sigframe(ka, regs, sizeof(*frame));
501 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
502 goto give_sigsegv;
503
504 err |= setup_sigcontext(regs, &frame->sf_sc);
505 err |= __copy_to_user(&frame->sf_mask, set, sizeof(*set));
506 if (err)
507 goto give_sigsegv;
508
509 /*
510 * Arguments to signal handler:
511 *
512 * a0 = signal number
513 * a1 = 0 (should be cause)
514 * a2 = pointer to struct sigcontext
515 *
516 * $25 and c0_epc point to the signal handler, $29 points to the
517 * struct sigframe.
518 */
519 regs->regs[ 4] = signr;
520 regs->regs[ 5] = 0;
521 regs->regs[ 6] = (unsigned long) &frame->sf_sc;
522 regs->regs[29] = (unsigned long) frame;
523 regs->regs[31] = (unsigned long) sig_return;
524 regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
525
526 DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
527 current->comm, current->pid,
528 frame, regs->cp0_epc, regs->regs[31]);
529 return 0;
530
531give_sigsegv:
532 force_sigsegv(signr, current);
533 return -EFAULT;
534}
535#endif
536
537static int setup_rt_frame(void *sig_return, struct k_sigaction *ka,
538 struct pt_regs *regs, int signr, sigset_t *set,
539 siginfo_t *info)
540{
541 struct rt_sigframe __user *frame;
542 int err = 0;
543
544 frame = get_sigframe(ka, regs, sizeof(*frame));
545 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
546 goto give_sigsegv;
547
548 /* Create siginfo. */
549 err |= copy_siginfo_to_user(&frame->rs_info, info);
550
551 /* Create the ucontext. */
552 err |= __put_user(0, &frame->rs_uc.uc_flags);
553 err |= __put_user(NULL, &frame->rs_uc.uc_link);
554 err |= __save_altstack(&frame->rs_uc.uc_stack, regs->regs[29]);
555 err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
556 err |= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));
557
558 if (err)
559 goto give_sigsegv;
560
561 /*
562 * Arguments to signal handler:
563 *
564 * a0 = signal number
565 * a1 = 0 (should be cause)
566 * a2 = pointer to ucontext
567 *
568 * $25 and c0_epc point to the signal handler, $29 points to
569 * the struct rt_sigframe.
570 */
571 regs->regs[ 4] = signr;
572 regs->regs[ 5] = (unsigned long) &frame->rs_info;
573 regs->regs[ 6] = (unsigned long) &frame->rs_uc;
574 regs->regs[29] = (unsigned long) frame;
575 regs->regs[31] = (unsigned long) sig_return;
576 regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
577
578 DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
579 current->comm, current->pid,
580 frame, regs->cp0_epc, regs->regs[31]);
581
582 return 0;
583
584give_sigsegv:
585 force_sigsegv(signr, current);
586 return -EFAULT;
587}
588
589struct mips_abi mips_abi = {
590#ifdef CONFIG_TRAD_SIGNALS
591 .setup_frame = setup_frame,
592 .signal_return_offset = offsetof(struct mips_vdso, signal_trampoline),
593#endif
594 .setup_rt_frame = setup_rt_frame,
595 .rt_signal_return_offset =
596 offsetof(struct mips_vdso, rt_signal_trampoline),
597 .restart = __NR_restart_syscall
598};
599
600static void handle_signal(unsigned long sig, siginfo_t *info,
601 struct k_sigaction *ka, struct pt_regs *regs)
602{
603 sigset_t *oldset = sigmask_to_save();
604 int ret;
605 struct mips_abi *abi = current->thread.abi;
606#ifdef CONFIG_CPU_MICROMIPS
607 void *vdso;
608 unsigned int tmp = (unsigned int)current->mm->context.vdso;
609
610 set_isa16_mode(tmp);
611 vdso = (void *)tmp;
612#else
613 void *vdso = current->mm->context.vdso;
614#endif
615
616 if (regs->regs[0]) {
617 switch(regs->regs[2]) {
618 case ERESTART_RESTARTBLOCK:
619 case ERESTARTNOHAND:
620 regs->regs[2] = EINTR;
621 break;
622 case ERESTARTSYS:
623 if (!(ka->sa.sa_flags & SA_RESTART)) {
624 regs->regs[2] = EINTR;
625 break;
626 }
627 /* fallthrough */
628 case ERESTARTNOINTR:
629 regs->regs[7] = regs->regs[26];
630 regs->regs[2] = regs->regs[0];
631 regs->cp0_epc -= 4;
632 }
633
634 regs->regs[0] = 0; /* Don't deal with this again. */
635 }
636
637 if (sig_uses_siginfo(ka))
638 ret = abi->setup_rt_frame(vdso + abi->rt_signal_return_offset,
639 ka, regs, sig, oldset, info);
640 else
641 ret = abi->setup_frame(vdso + abi->signal_return_offset,
642 ka, regs, sig, oldset);
643
644 if (ret)
645 return;
646
647 signal_delivered(sig, info, ka, regs, 0);
648}
649
650static void do_signal(struct pt_regs *regs)
651{
652 struct k_sigaction ka;
653 siginfo_t info;
654 int signr;
655
656 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
657 if (signr > 0) {
658 /* Whee! Actually deliver the signal. */
659 handle_signal(signr, &info, &ka, regs);
660 return;
661 }
662
663 if (regs->regs[0]) {
664 switch (regs->regs[2]) {
665 case ERESTARTNOHAND:
666 case ERESTARTSYS:
667 case ERESTARTNOINTR:
668 regs->regs[2] = regs->regs[0];
669 regs->regs[7] = regs->regs[26];
670 regs->cp0_epc -= 4;
671 break;
672
673 case ERESTART_RESTARTBLOCK:
674 regs->regs[2] = current->thread.abi->restart;
675 regs->regs[7] = regs->regs[26];
676 regs->cp0_epc -= 4;
677 break;
678 }
679 regs->regs[0] = 0; /* Don't deal with this again. */
680 }
681
682 /*
683 * If there's no signal to deliver, we just put the saved sigmask
684 * back
685 */
686 restore_saved_sigmask();
687}
688
689/*
690 * notification of userspace execution resumption
691 * - triggered by the TIF_WORK_MASK flags
692 */
693asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
694 __u32 thread_info_flags)
695{
696 local_irq_enable();
697
698 user_exit();
699
700 /* deal with pending signal delivery */
701 if (thread_info_flags & _TIF_SIGPENDING)
702 do_signal(regs);
703
704 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
705 clear_thread_flag(TIF_NOTIFY_RESUME);
706 tracehook_notify_resume(regs);
707 }
708
709 user_enter();
710}
711
712#ifdef CONFIG_SMP
713#ifndef CONFIG_EVA
714static int smp_save_fp_context(struct sigcontext __user *sc)
715{
716 return raw_cpu_has_fpu
717 ? _save_fp_context(sc)
718 : copy_fp_to_sigcontext(sc);
719}
720
721static int smp_restore_fp_context(struct sigcontext __user *sc)
722{
723 return raw_cpu_has_fpu
724 ? _restore_fp_context(sc)
725 : copy_fp_from_sigcontext(sc);
726}
727#endif /* CONFIG_EVA */
728#endif
729
730static int signal_setup(void)
731{
732#ifndef CONFIG_EVA
733#ifdef CONFIG_SMP
734 /* For now just do the cpu_has_fpu check when the functions are invoked */
735 save_fp_context = smp_save_fp_context;
736 restore_fp_context = smp_restore_fp_context;
737#else
738 if (cpu_has_fpu) {
739 save_fp_context = _save_fp_context;
740 restore_fp_context = _restore_fp_context;
741 } else {
742 save_fp_context = copy_fp_from_sigcontext;
743 restore_fp_context = copy_fp_to_sigcontext;
744 }
745#endif /* CONFIG_SMP */
746#else
747 save_fp_context = copy_fp_from_sigcontext;;
748 restore_fp_context = copy_fp_to_sigcontext;
749#endif
750
751 return 0;
752}
753
754arch_initcall(signal_setup);