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(&current->sighand->siglock);
260	current->saved_sigmask = current->blocked;
261	current->blocked = newset;
262	recalc_sigpending();
263	spin_unlock_irq(&current->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(&current->sighand->siglock);
289	current->saved_sigmask = current->blocked;
290	current->blocked = newset;
291	recalc_sigpending();
292	spin_unlock_irq(&current->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(&current->sighand->siglock);
365	current->blocked = blocked;
366	recalc_sigpending();
367	spin_unlock_irq(&current->sighand->siglock);
368
369	sig = restore_sigcontext(&regs, &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" (&regs));
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(&current->sighand->siglock);
404	current->blocked = set;
405	recalc_sigpending();
406	spin_unlock_irq(&current->sighand->siglock);
407
408	sig = restore_sigcontext(&regs, &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" (&regs));
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(&current->sighand->siglock);
583	sigorsets(&current->blocked, &current->blocked, &ka->sa.sa_mask);
584	if (!(ka->sa.sa_flags & SA_NODEFER))
585		sigaddset(&current->blocked, sig);
586	recalc_sigpending();
587	spin_unlock_irq(&current->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 = &current->saved_sigmask;
609	else
610		oldset = &current->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, &current->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);