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-rw-r--r--arch/sh/kernel/signal_32.c629
1 files changed, 629 insertions, 0 deletions
diff --git a/arch/sh/kernel/signal_32.c b/arch/sh/kernel/signal_32.c
new file mode 100644
index 000000000000..ca754fd42437
--- /dev/null
+++ b/arch/sh/kernel/signal_32.c
@@ -0,0 +1,629 @@
1/*
2 * linux/arch/sh/kernel/signal.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 *
6 * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
7 *
8 * SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
9 *
10 */
11#include <linux/sched.h>
12#include <linux/mm.h>
13#include <linux/smp.h>
14#include <linux/kernel.h>
15#include <linux/signal.h>
16#include <linux/errno.h>
17#include <linux/wait.h>
18#include <linux/ptrace.h>
19#include <linux/unistd.h>
20#include <linux/stddef.h>
21#include <linux/tty.h>
22#include <linux/elf.h>
23#include <linux/personality.h>
24#include <linux/binfmts.h>
25#include <linux/freezer.h>
26#include <linux/io.h>
27#include <asm/system.h>
28#include <asm/ucontext.h>
29#include <asm/uaccess.h>
30#include <asm/pgtable.h>
31#include <asm/cacheflush.h>
32
33#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
34
35/*
36 * Atomically swap in the new signal mask, and wait for a signal.
37 */
38asmlinkage int
39sys_sigsuspend(old_sigset_t mask,
40 unsigned long r5, unsigned long r6, unsigned long r7,
41 struct pt_regs __regs)
42{
43 mask &= _BLOCKABLE;
44 spin_lock_irq(&current->sighand->siglock);
45 current->saved_sigmask = current->blocked;
46 siginitset(&current->blocked, mask);
47 recalc_sigpending();
48 spin_unlock_irq(&current->sighand->siglock);
49
50 current->state = TASK_INTERRUPTIBLE;
51 schedule();
52 set_thread_flag(TIF_RESTORE_SIGMASK);
53 return -ERESTARTNOHAND;
54}
55
56asmlinkage int
57sys_sigaction(int sig, const struct old_sigaction __user *act,
58 struct old_sigaction __user *oact)
59{
60 struct k_sigaction new_ka, old_ka;
61 int ret;
62
63 if (act) {
64 old_sigset_t mask;
65 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
66 __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
67 __get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
68 return -EFAULT;
69 __get_user(new_ka.sa.sa_flags, &act->sa_flags);
70 __get_user(mask, &act->sa_mask);
71 siginitset(&new_ka.sa.sa_mask, mask);
72 }
73
74 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
75
76 if (!ret && oact) {
77 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
78 __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
79 __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
80 return -EFAULT;
81 __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
82 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
83 }
84
85 return ret;
86}
87
88asmlinkage int
89sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
90 unsigned long r6, unsigned long r7,
91 struct pt_regs __regs)
92{
93 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
94
95 return do_sigaltstack(uss, uoss, regs->regs[15]);
96}
97
98
99/*
100 * Do a signal return; undo the signal stack.
101 */
102
103#define MOVW(n) (0x9300|((n)-2)) /* Move mem word at PC+n to R3 */
104#if defined(CONFIG_CPU_SH2)
105#define TRAP_NOARG 0xc320 /* Syscall w/no args (NR in R3) */
106#else
107#define TRAP_NOARG 0xc310 /* Syscall w/no args (NR in R3) */
108#endif
109#define OR_R0_R0 0x200b /* or r0,r0 (insert to avoid hardware bug) */
110
111struct sigframe
112{
113 struct sigcontext sc;
114 unsigned long extramask[_NSIG_WORDS-1];
115 u16 retcode[8];
116};
117
118struct rt_sigframe
119{
120 struct siginfo info;
121 struct ucontext uc;
122 u16 retcode[8];
123};
124
125#ifdef CONFIG_SH_FPU
126static inline int restore_sigcontext_fpu(struct sigcontext __user *sc)
127{
128 struct task_struct *tsk = current;
129
130 if (!(current_cpu_data.flags & CPU_HAS_FPU))
131 return 0;
132
133 set_used_math();
134 return __copy_from_user(&tsk->thread.fpu.hard, &sc->sc_fpregs[0],
135 sizeof(long)*(16*2+2));
136}
137
138static inline int save_sigcontext_fpu(struct sigcontext __user *sc,
139 struct pt_regs *regs)
140{
141 struct task_struct *tsk = current;
142
143 if (!(current_cpu_data.flags & CPU_HAS_FPU))
144 return 0;
145
146 if (!used_math()) {
147 __put_user(0, &sc->sc_ownedfp);
148 return 0;
149 }
150
151 __put_user(1, &sc->sc_ownedfp);
152
153 /* This will cause a "finit" to be triggered by the next
154 attempted FPU operation by the 'current' process.
155 */
156 clear_used_math();
157
158 unlazy_fpu(tsk, regs);
159 return __copy_to_user(&sc->sc_fpregs[0], &tsk->thread.fpu.hard,
160 sizeof(long)*(16*2+2));
161}
162#endif /* CONFIG_SH_FPU */
163
164static int
165restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *r0_p)
166{
167 unsigned int err = 0;
168
169#define COPY(x) err |= __get_user(regs->x, &sc->sc_##x)
170 COPY(regs[1]);
171 COPY(regs[2]); COPY(regs[3]);
172 COPY(regs[4]); COPY(regs[5]);
173 COPY(regs[6]); COPY(regs[7]);
174 COPY(regs[8]); COPY(regs[9]);
175 COPY(regs[10]); COPY(regs[11]);
176 COPY(regs[12]); COPY(regs[13]);
177 COPY(regs[14]); COPY(regs[15]);
178 COPY(gbr); COPY(mach);
179 COPY(macl); COPY(pr);
180 COPY(sr); COPY(pc);
181#undef COPY
182
183#ifdef CONFIG_SH_FPU
184 if (current_cpu_data.flags & CPU_HAS_FPU) {
185 int owned_fp;
186 struct task_struct *tsk = current;
187
188 regs->sr |= SR_FD; /* Release FPU */
189 clear_fpu(tsk, regs);
190 clear_used_math();
191 __get_user (owned_fp, &sc->sc_ownedfp);
192 if (owned_fp)
193 err |= restore_sigcontext_fpu(sc);
194 }
195#endif
196
197 regs->tra = -1; /* disable syscall checks */
198 err |= __get_user(*r0_p, &sc->sc_regs[0]);
199 return err;
200}
201
202asmlinkage int sys_sigreturn(unsigned long r4, unsigned long r5,
203 unsigned long r6, unsigned long r7,
204 struct pt_regs __regs)
205{
206 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
207 struct sigframe __user *frame = (struct sigframe __user *)regs->regs[15];
208 sigset_t set;
209 int r0;
210
211 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
212 goto badframe;
213
214 if (__get_user(set.sig[0], &frame->sc.oldmask)
215 || (_NSIG_WORDS > 1
216 && __copy_from_user(&set.sig[1], &frame->extramask,
217 sizeof(frame->extramask))))
218 goto badframe;
219
220 sigdelsetmask(&set, ~_BLOCKABLE);
221
222 spin_lock_irq(&current->sighand->siglock);
223 current->blocked = set;
224 recalc_sigpending();
225 spin_unlock_irq(&current->sighand->siglock);
226
227 if (restore_sigcontext(regs, &frame->sc, &r0))
228 goto badframe;
229 return r0;
230
231badframe:
232 force_sig(SIGSEGV, current);
233 return 0;
234}
235
236asmlinkage int sys_rt_sigreturn(unsigned long r4, unsigned long r5,
237 unsigned long r6, unsigned long r7,
238 struct pt_regs __regs)
239{
240 struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
241 struct rt_sigframe __user *frame = (struct rt_sigframe __user *)regs->regs[15];
242 sigset_t set;
243 stack_t st;
244 int r0;
245
246 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
247 goto badframe;
248
249 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
250 goto badframe;
251
252 sigdelsetmask(&set, ~_BLOCKABLE);
253 spin_lock_irq(&current->sighand->siglock);
254 current->blocked = set;
255 recalc_sigpending();
256 spin_unlock_irq(&current->sighand->siglock);
257
258 if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &r0))
259 goto badframe;
260
261 if (__copy_from_user(&st, &frame->uc.uc_stack, sizeof(st)))
262 goto badframe;
263 /* It is more difficult to avoid calling this function than to
264 call it and ignore errors. */
265 do_sigaltstack((const stack_t __user *)&st, NULL, (unsigned long)frame);
266
267 return r0;
268
269badframe:
270 force_sig(SIGSEGV, current);
271 return 0;
272}
273
274/*
275 * Set up a signal frame.
276 */
277
278static int
279setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
280 unsigned long mask)
281{
282 int err = 0;
283
284#define COPY(x) err |= __put_user(regs->x, &sc->sc_##x)
285 COPY(regs[0]); COPY(regs[1]);
286 COPY(regs[2]); COPY(regs[3]);
287 COPY(regs[4]); COPY(regs[5]);
288 COPY(regs[6]); COPY(regs[7]);
289 COPY(regs[8]); COPY(regs[9]);
290 COPY(regs[10]); COPY(regs[11]);
291 COPY(regs[12]); COPY(regs[13]);
292 COPY(regs[14]); COPY(regs[15]);
293 COPY(gbr); COPY(mach);
294 COPY(macl); COPY(pr);
295 COPY(sr); COPY(pc);
296#undef COPY
297
298#ifdef CONFIG_SH_FPU
299 err |= save_sigcontext_fpu(sc, regs);
300#endif
301
302 /* non-iBCS2 extensions.. */
303 err |= __put_user(mask, &sc->oldmask);
304
305 return err;
306}
307
308/*
309 * Determine which stack to use..
310 */
311static inline void __user *
312get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
313{
314 if (ka->sa.sa_flags & SA_ONSTACK) {
315 if (sas_ss_flags(sp) == 0)
316 sp = current->sas_ss_sp + current->sas_ss_size;
317 }
318
319 return (void __user *)((sp - frame_size) & -8ul);
320}
321
322/* These symbols are defined with the addresses in the vsyscall page.
323 See vsyscall-trapa.S. */
324extern void __user __kernel_sigreturn;
325extern void __user __kernel_rt_sigreturn;
326
327static int setup_frame(int sig, struct k_sigaction *ka,
328 sigset_t *set, struct pt_regs *regs)
329{
330 struct sigframe __user *frame;
331 int err = 0;
332 int signal;
333
334 frame = get_sigframe(ka, regs->regs[15], sizeof(*frame));
335
336 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
337 goto give_sigsegv;
338
339 signal = current_thread_info()->exec_domain
340 && current_thread_info()->exec_domain->signal_invmap
341 && sig < 32
342 ? current_thread_info()->exec_domain->signal_invmap[sig]
343 : sig;
344
345 err |= setup_sigcontext(&frame->sc, regs, set->sig[0]);
346
347 if (_NSIG_WORDS > 1)
348 err |= __copy_to_user(frame->extramask, &set->sig[1],
349 sizeof(frame->extramask));
350
351 /* Set up to return from userspace. If provided, use a stub
352 already in userspace. */
353 if (ka->sa.sa_flags & SA_RESTORER) {
354 regs->pr = (unsigned long) ka->sa.sa_restorer;
355#ifdef CONFIG_VSYSCALL
356 } else if (likely(current->mm->context.vdso)) {
357 regs->pr = VDSO_SYM(&__kernel_sigreturn);
358#endif
359 } else {
360 /* Generate return code (system call to sigreturn) */
361 err |= __put_user(MOVW(7), &frame->retcode[0]);
362 err |= __put_user(TRAP_NOARG, &frame->retcode[1]);
363 err |= __put_user(OR_R0_R0, &frame->retcode[2]);
364 err |= __put_user(OR_R0_R0, &frame->retcode[3]);
365 err |= __put_user(OR_R0_R0, &frame->retcode[4]);
366 err |= __put_user(OR_R0_R0, &frame->retcode[5]);
367 err |= __put_user(OR_R0_R0, &frame->retcode[6]);
368 err |= __put_user((__NR_sigreturn), &frame->retcode[7]);
369 regs->pr = (unsigned long) frame->retcode;
370 }
371
372 if (err)
373 goto give_sigsegv;
374
375 /* Set up registers for signal handler */
376 regs->regs[15] = (unsigned long) frame;
377 regs->regs[4] = signal; /* Arg for signal handler */
378 regs->regs[5] = 0;
379 regs->regs[6] = (unsigned long) &frame->sc;
380 regs->pc = (unsigned long) ka->sa.sa_handler;
381
382 set_fs(USER_DS);
383
384 pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n",
385 current->comm, task_pid_nr(current), frame, regs->pc, regs->pr);
386
387 flush_cache_sigtramp(regs->pr);
388
389 if ((-regs->pr & (L1_CACHE_BYTES-1)) < sizeof(frame->retcode))
390 flush_cache_sigtramp(regs->pr + L1_CACHE_BYTES);
391
392 return 0;
393
394give_sigsegv:
395 force_sigsegv(sig, current);
396 return -EFAULT;
397}
398
399static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
400 sigset_t *set, struct pt_regs *regs)
401{
402 struct rt_sigframe __user *frame;
403 int err = 0;
404 int signal;
405
406 frame = get_sigframe(ka, regs->regs[15], sizeof(*frame));
407
408 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
409 goto give_sigsegv;
410
411 signal = current_thread_info()->exec_domain
412 && current_thread_info()->exec_domain->signal_invmap
413 && sig < 32
414 ? current_thread_info()->exec_domain->signal_invmap[sig]
415 : sig;
416
417 err |= copy_siginfo_to_user(&frame->info, info);
418
419 /* Create the ucontext. */
420 err |= __put_user(0, &frame->uc.uc_flags);
421 err |= __put_user(0, &frame->uc.uc_link);
422 err |= __put_user((void *)current->sas_ss_sp,
423 &frame->uc.uc_stack.ss_sp);
424 err |= __put_user(sas_ss_flags(regs->regs[15]),
425 &frame->uc.uc_stack.ss_flags);
426 err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
427 err |= setup_sigcontext(&frame->uc.uc_mcontext,
428 regs, set->sig[0]);
429 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
430
431 /* Set up to return from userspace. If provided, use a stub
432 already in userspace. */
433 if (ka->sa.sa_flags & SA_RESTORER) {
434 regs->pr = (unsigned long) ka->sa.sa_restorer;
435#ifdef CONFIG_VSYSCALL
436 } else if (likely(current->mm->context.vdso)) {
437 regs->pr = VDSO_SYM(&__kernel_rt_sigreturn);
438#endif
439 } else {
440 /* Generate return code (system call to rt_sigreturn) */
441 err |= __put_user(MOVW(7), &frame->retcode[0]);
442 err |= __put_user(TRAP_NOARG, &frame->retcode[1]);
443 err |= __put_user(OR_R0_R0, &frame->retcode[2]);
444 err |= __put_user(OR_R0_R0, &frame->retcode[3]);
445 err |= __put_user(OR_R0_R0, &frame->retcode[4]);
446 err |= __put_user(OR_R0_R0, &frame->retcode[5]);
447 err |= __put_user(OR_R0_R0, &frame->retcode[6]);
448 err |= __put_user((__NR_rt_sigreturn), &frame->retcode[7]);
449 regs->pr = (unsigned long) frame->retcode;
450 }
451
452 if (err)
453 goto give_sigsegv;
454
455 /* Set up registers for signal handler */
456 regs->regs[15] = (unsigned long) frame;
457 regs->regs[4] = signal; /* Arg for signal handler */
458 regs->regs[5] = (unsigned long) &frame->info;
459 regs->regs[6] = (unsigned long) &frame->uc;
460 regs->pc = (unsigned long) ka->sa.sa_handler;
461
462 set_fs(USER_DS);
463
464 pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n",
465 current->comm, task_pid_nr(current), frame, regs->pc, regs->pr);
466
467 flush_cache_sigtramp(regs->pr);
468
469 if ((-regs->pr & (L1_CACHE_BYTES-1)) < sizeof(frame->retcode))
470 flush_cache_sigtramp(regs->pr + L1_CACHE_BYTES);
471
472 return 0;
473
474give_sigsegv:
475 force_sigsegv(sig, current);
476 return -EFAULT;
477}
478
479/*
480 * OK, we're invoking a handler
481 */
482
483static int
484handle_signal(unsigned long sig, struct k_sigaction *ka, siginfo_t *info,
485 sigset_t *oldset, struct pt_regs *regs, unsigned int save_r0)
486{
487 int ret;
488
489 /* Are we from a system call? */
490 if (regs->tra >= 0) {
491 /* If so, check system call restarting.. */
492 switch (regs->regs[0]) {
493 case -ERESTART_RESTARTBLOCK:
494 case -ERESTARTNOHAND:
495 regs->regs[0] = -EINTR;
496 break;
497
498 case -ERESTARTSYS:
499 if (!(ka->sa.sa_flags & SA_RESTART)) {
500 regs->regs[0] = -EINTR;
501 break;
502 }
503 /* fallthrough */
504 case -ERESTARTNOINTR:
505 regs->regs[0] = save_r0;
506 regs->pc -= instruction_size(
507 ctrl_inw(regs->pc - 4));
508 break;
509 }
510#ifdef CONFIG_GUSA
511 } else {
512 /* gUSA handling */
513 preempt_disable();
514
515 if (regs->regs[15] >= 0xc0000000) {
516 int offset = (int)regs->regs[15];
517
518 /* Reset stack pointer: clear critical region mark */
519 regs->regs[15] = regs->regs[1];
520 if (regs->pc < regs->regs[0])
521 /* Go to rewind point #1 */
522 regs->pc = regs->regs[0] + offset -
523 instruction_size(ctrl_inw(regs->pc-4));
524 }
525
526 preempt_enable_no_resched();
527#endif
528 }
529
530 /* Set up the stack frame */
531 if (ka->sa.sa_flags & SA_SIGINFO)
532 ret = setup_rt_frame(sig, ka, info, oldset, regs);
533 else
534 ret = setup_frame(sig, ka, oldset, regs);
535
536 if (ka->sa.sa_flags & SA_ONESHOT)
537 ka->sa.sa_handler = SIG_DFL;
538
539 if (ret == 0) {
540 spin_lock_irq(&current->sighand->siglock);
541 sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
542 if (!(ka->sa.sa_flags & SA_NODEFER))
543 sigaddset(&current->blocked,sig);
544 recalc_sigpending();
545 spin_unlock_irq(&current->sighand->siglock);
546 }
547
548 return ret;
549}
550
551/*
552 * Note that 'init' is a special process: it doesn't get signals it doesn't
553 * want to handle. Thus you cannot kill init even with a SIGKILL even by
554 * mistake.
555 *
556 * Note that we go through the signals twice: once to check the signals that
557 * the kernel can handle, and then we build all the user-level signal handling
558 * stack-frames in one go after that.
559 */
560static void do_signal(struct pt_regs *regs, unsigned int save_r0)
561{
562 siginfo_t info;
563 int signr;
564 struct k_sigaction ka;
565 sigset_t *oldset;
566
567 /*
568 * We want the common case to go fast, which
569 * is why we may in certain cases get here from
570 * kernel mode. Just return without doing anything
571 * if so.
572 */
573 if (!user_mode(regs))
574 return;
575
576 if (try_to_freeze())
577 goto no_signal;
578
579 if (test_thread_flag(TIF_RESTORE_SIGMASK))
580 oldset = &current->saved_sigmask;
581 else
582 oldset = &current->blocked;
583
584 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
585 if (signr > 0) {
586 /* Whee! Actually deliver the signal. */
587 if (handle_signal(signr, &ka, &info, oldset,
588 regs, save_r0) == 0) {
589 /* a signal was successfully delivered; the saved
590 * sigmask will have been stored in the signal frame,
591 * and will be restored by sigreturn, so we can simply
592 * clear the TIF_RESTORE_SIGMASK flag */
593 if (test_thread_flag(TIF_RESTORE_SIGMASK))
594 clear_thread_flag(TIF_RESTORE_SIGMASK);
595 }
596
597 return;
598 }
599
600 no_signal:
601 /* Did we come from a system call? */
602 if (regs->tra >= 0) {
603 /* Restart the system call - no handlers present */
604 if (regs->regs[0] == -ERESTARTNOHAND ||
605 regs->regs[0] == -ERESTARTSYS ||
606 regs->regs[0] == -ERESTARTNOINTR) {
607 regs->regs[0] = save_r0;
608 regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
609 } else if (regs->regs[0] == -ERESTART_RESTARTBLOCK) {
610 regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
611 regs->regs[3] = __NR_restart_syscall;
612 }
613 }
614
615 /* if there's no signal to deliver, we just put the saved sigmask
616 * back */
617 if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
618 clear_thread_flag(TIF_RESTORE_SIGMASK);
619 sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
620 }
621}
622
623asmlinkage void do_notify_resume(struct pt_regs *regs, unsigned int save_r0,
624 __u32 thread_info_flags)
625{
626 /* deal with pending signal delivery */
627 if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
628 do_signal(regs, save_r0);
629}