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
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.
11 #include <linux/cache.h>
12 #include <linux/context_tracking.h>
13 #include <linux/irqflags.h>
14 #include <linux/sched.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>
31 #include <linux/bitops.h>
32 #include <asm/cacheflush.h>
35 #include <asm/ucontext.h>
36 #include <asm/cpu-features.h>
42 #include "signal-common.h"
44 static int (*save_fp_context)(struct sigcontext __user *sc);
45 static int (*restore_fp_context)(struct sigcontext __user *sc);
47 extern asmlinkage int _save_fp_context(struct sigcontext __user *sc);
48 extern asmlinkage int _restore_fp_context(struct sigcontext __user *sc);
51 u32 sf_ass[4]; /* argument save space for o32 */
52 u32 sf_pad[2]; /* Was: signal trampoline */
53 struct sigcontext sf_sc;
58 u32 rs_ass[4]; /* argument save space for o32 */
59 u32 rs_pad[2]; /* Was: signal trampoline */
60 struct siginfo rs_info;
61 struct ucontext rs_uc;
65 * Thread saved context copy to/from a signal context presumed to be on the
66 * user stack, and therefore accessed with appropriate macros from uaccess.h.
68 static int copy_fp_to_sigcontext(struct sigcontext __user *sc)
73 for (i = 0; i < NUM_FPU_REGS; i++) {
75 __put_user(get_fpr64(¤t->thread.fpu.fpr[i], 0),
78 err |= __put_user(current->thread.fpu.fcr31, &sc->sc_fpc_csr);
83 static int copy_fp_from_sigcontext(struct sigcontext __user *sc)
89 for (i = 0; i < NUM_FPU_REGS; i++) {
90 err |= __get_user(fpr_val, &sc->sc_fpregs[i]);
91 set_fpr64(¤t->thread.fpu.fpr[i], 0, fpr_val);
93 err |= __get_user(current->thread.fpu.fcr31, &sc->sc_fpc_csr);
101 static int protected_save_fp_context(struct sigcontext __user *sc)
107 if (is_fpu_owner()) {
108 err = save_fp_context(sc);
112 err = copy_fp_to_sigcontext(sc);
116 /* touch the sigcontext and try again */
117 err = __put_user(0, &sc->sc_fpregs[0]) |
118 __put_user(0, &sc->sc_fpregs[31]) |
119 __put_user(0, &sc->sc_fpc_csr);
121 break; /* really bad sigcontext */
125 * EVA does not have FPU EVA instructions so saving fpu context directly
129 err = save_fp_context(sc); /* this might fail */
134 static int protected_restore_fp_context(struct sigcontext __user *sc)
136 int err, tmp __maybe_unused;
140 if (is_fpu_owner()) {
141 err = restore_fp_context(sc);
145 err = copy_fp_from_sigcontext(sc);
149 /* touch the sigcontext and try again */
150 err = __get_user(tmp, &sc->sc_fpregs[0]) |
151 __get_user(tmp, &sc->sc_fpregs[31]) |
152 __get_user(tmp, &sc->sc_fpc_csr);
154 break; /* really bad sigcontext */
158 * EVA does not have FPU EVA instructions so restoring fpu context
159 * directly does not work.
162 err = restore_fp_context(sc); /* this might fail */
167 int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
171 unsigned int used_math;
173 err |= __put_user(regs->cp0_epc, &sc->sc_pc);
175 err |= __put_user(0, &sc->sc_regs[0]);
176 for (i = 1; i < 32; i++)
177 err |= __put_user(regs->regs[i], &sc->sc_regs[i]);
179 #ifdef CONFIG_CPU_HAS_SMARTMIPS
180 err |= __put_user(regs->acx, &sc->sc_acx);
182 err |= __put_user(regs->hi, &sc->sc_mdhi);
183 err |= __put_user(regs->lo, &sc->sc_mdlo);
185 err |= __put_user(mfhi1(), &sc->sc_hi1);
186 err |= __put_user(mflo1(), &sc->sc_lo1);
187 err |= __put_user(mfhi2(), &sc->sc_hi2);
188 err |= __put_user(mflo2(), &sc->sc_lo2);
189 err |= __put_user(mfhi3(), &sc->sc_hi3);
190 err |= __put_user(mflo3(), &sc->sc_lo3);
191 err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
194 used_math = !!used_math();
195 err |= __put_user(used_math, &sc->sc_used_math);
199 * Save FPU state to signal context. Signal handler
200 * will "inherit" current FPU state.
202 err |= protected_save_fp_context(sc);
207 int fpcsr_pending(unsigned int __user *fpcsr)
210 unsigned int csr, enabled;
212 err = __get_user(csr, fpcsr);
213 enabled = FPU_CSR_UNI_X | ((csr & FPU_CSR_ALL_E) << 5);
215 * If the signal handler set some FPU exceptions, clear it and
220 err |= __put_user(csr, fpcsr);
227 check_and_restore_fp_context(struct sigcontext __user *sc)
231 err = sig = fpcsr_pending(&sc->sc_fpc_csr);
234 err |= protected_restore_fp_context(sc);
238 int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
240 unsigned int used_math;
245 /* Always make any pending restarted system calls return -EINTR */
246 current_thread_info()->restart_block.fn = do_no_restart_syscall;
248 err |= __get_user(regs->cp0_epc, &sc->sc_pc);
250 #ifdef CONFIG_CPU_HAS_SMARTMIPS
251 err |= __get_user(regs->acx, &sc->sc_acx);
253 err |= __get_user(regs->hi, &sc->sc_mdhi);
254 err |= __get_user(regs->lo, &sc->sc_mdlo);
256 err |= __get_user(treg, &sc->sc_hi1); mthi1(treg);
257 err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
258 err |= __get_user(treg, &sc->sc_hi2); mthi2(treg);
259 err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
260 err |= __get_user(treg, &sc->sc_hi3); mthi3(treg);
261 err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
262 err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
265 for (i = 1; i < 32; i++)
266 err |= __get_user(regs->regs[i], &sc->sc_regs[i]);
268 err |= __get_user(used_math, &sc->sc_used_math);
269 conditional_used_math(used_math);
272 /* restore fpu context if we have used it before */
274 err = check_and_restore_fp_context(sc);
276 /* signal handler may have used FPU. Give it up. */
283 void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
288 /* Default to using normal stack */
292 * FPU emulator may have it's own trampoline active just
293 * above the user stack, 16-bytes before the next lowest
294 * 16 byte boundary. Try to avoid trashing it.
298 /* This is the X/Open sanctioned signal stack switching. */
299 if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags (sp) == 0))
300 sp = current->sas_ss_sp + current->sas_ss_size;
302 return (void __user *)((sp - frame_size) & (ICACHE_REFILLS_WORKAROUND_WAR ? ~(cpu_icache_line_size()-1) : ALMASK));
306 * Atomically swap in the new signal mask, and wait for a signal.
309 #ifdef CONFIG_TRAD_SIGNALS
310 SYSCALL_DEFINE1(sigsuspend, sigset_t __user *, uset)
312 return sys_rt_sigsuspend(uset, sizeof(sigset_t));
316 #ifdef CONFIG_TRAD_SIGNALS
317 SYSCALL_DEFINE3(sigaction, int, sig, const struct sigaction __user *, act,
318 struct sigaction __user *, oact)
320 struct k_sigaction new_ka, old_ka;
327 if (!access_ok(VERIFY_READ, act, sizeof(*act)))
329 err |= __get_user(new_ka.sa.sa_handler, &act->sa_handler);
330 err |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
331 err |= __get_user(mask, &act->sa_mask.sig[0]);
335 siginitset(&new_ka.sa.sa_mask, mask);
338 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
341 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)))
343 err |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
344 err |= __put_user(old_ka.sa.sa_handler, &oact->sa_handler);
345 err |= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig);
346 err |= __put_user(0, &oact->sa_mask.sig[1]);
347 err |= __put_user(0, &oact->sa_mask.sig[2]);
348 err |= __put_user(0, &oact->sa_mask.sig[3]);
357 #ifdef CONFIG_TRAD_SIGNALS
358 asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs)
360 struct sigframe __user *frame;
364 frame = (struct sigframe __user *) regs.regs[29];
365 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
367 if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked)))
370 set_current_blocked(&blocked);
372 sig = restore_sigcontext(®s, &frame->sf_sc);
376 force_sig(sig, current);
379 * Don't let your children do this ...
381 __asm__ __volatile__(
389 force_sig(SIGSEGV, current);
391 #endif /* CONFIG_TRAD_SIGNALS */
393 asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
395 struct rt_sigframe __user *frame;
399 frame = (struct rt_sigframe __user *) regs.regs[29];
400 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
402 if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set)))
405 set_current_blocked(&set);
407 sig = restore_sigcontext(®s, &frame->rs_uc.uc_mcontext);
411 force_sig(sig, current);
413 if (restore_altstack(&frame->rs_uc.uc_stack))
417 * Don't let your children do this ...
419 __asm__ __volatile__(
427 force_sig(SIGSEGV, current);
430 #ifdef CONFIG_TRAD_SIGNALS
431 static int setup_frame(void *sig_return, struct k_sigaction *ka,
432 struct pt_regs *regs, int signr, sigset_t *set)
434 struct sigframe __user *frame;
437 frame = get_sigframe(ka, regs, sizeof(*frame));
438 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
441 err |= setup_sigcontext(regs, &frame->sf_sc);
442 err |= __copy_to_user(&frame->sf_mask, set, sizeof(*set));
447 * Arguments to signal handler:
450 * a1 = 0 (should be cause)
451 * a2 = pointer to struct sigcontext
453 * $25 and c0_epc point to the signal handler, $29 points to the
456 regs->regs[ 4] = signr;
458 regs->regs[ 6] = (unsigned long) &frame->sf_sc;
459 regs->regs[29] = (unsigned long) frame;
460 regs->regs[31] = (unsigned long) sig_return;
461 regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
463 DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
464 current->comm, current->pid,
465 frame, regs->cp0_epc, regs->regs[31]);
469 force_sigsegv(signr, current);
474 static int setup_rt_frame(void *sig_return, struct k_sigaction *ka,
475 struct pt_regs *regs, int signr, sigset_t *set,
478 struct rt_sigframe __user *frame;
481 frame = get_sigframe(ka, regs, sizeof(*frame));
482 if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
485 /* Create siginfo. */
486 err |= copy_siginfo_to_user(&frame->rs_info, info);
488 /* Create the ucontext. */
489 err |= __put_user(0, &frame->rs_uc.uc_flags);
490 err |= __put_user(NULL, &frame->rs_uc.uc_link);
491 err |= __save_altstack(&frame->rs_uc.uc_stack, regs->regs[29]);
492 err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
493 err |= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));
499 * Arguments to signal handler:
502 * a1 = 0 (should be cause)
503 * a2 = pointer to ucontext
505 * $25 and c0_epc point to the signal handler, $29 points to
506 * the struct rt_sigframe.
508 regs->regs[ 4] = signr;
509 regs->regs[ 5] = (unsigned long) &frame->rs_info;
510 regs->regs[ 6] = (unsigned long) &frame->rs_uc;
511 regs->regs[29] = (unsigned long) frame;
512 regs->regs[31] = (unsigned long) sig_return;
513 regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
515 DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
516 current->comm, current->pid,
517 frame, regs->cp0_epc, regs->regs[31]);
522 force_sigsegv(signr, current);
526 struct mips_abi mips_abi = {
527 #ifdef CONFIG_TRAD_SIGNALS
528 .setup_frame = setup_frame,
529 .signal_return_offset = offsetof(struct mips_vdso, signal_trampoline),
531 .setup_rt_frame = setup_rt_frame,
532 .rt_signal_return_offset =
533 offsetof(struct mips_vdso, rt_signal_trampoline),
534 .restart = __NR_restart_syscall
537 static void handle_signal(unsigned long sig, siginfo_t *info,
538 struct k_sigaction *ka, struct pt_regs *regs)
540 sigset_t *oldset = sigmask_to_save();
542 struct mips_abi *abi = current->thread.abi;
543 #ifdef CONFIG_CPU_MICROMIPS
545 unsigned int tmp = (unsigned int)current->mm->context.vdso;
550 void *vdso = current->mm->context.vdso;
554 switch(regs->regs[2]) {
555 case ERESTART_RESTARTBLOCK:
557 regs->regs[2] = EINTR;
560 if (!(ka->sa.sa_flags & SA_RESTART)) {
561 regs->regs[2] = EINTR;
566 regs->regs[7] = regs->regs[26];
567 regs->regs[2] = regs->regs[0];
571 regs->regs[0] = 0; /* Don't deal with this again. */
574 if (sig_uses_siginfo(ka))
575 ret = abi->setup_rt_frame(vdso + abi->rt_signal_return_offset,
576 ka, regs, sig, oldset, info);
578 ret = abi->setup_frame(vdso + abi->signal_return_offset,
579 ka, regs, sig, oldset);
584 signal_delivered(sig, info, ka, regs, 0);
587 static void do_signal(struct pt_regs *regs)
589 struct k_sigaction ka;
593 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
595 /* Whee! Actually deliver the signal. */
596 handle_signal(signr, &info, &ka, regs);
601 switch (regs->regs[2]) {
605 regs->regs[2] = regs->regs[0];
606 regs->regs[7] = regs->regs[26];
610 case ERESTART_RESTARTBLOCK:
611 regs->regs[2] = current->thread.abi->restart;
612 regs->regs[7] = regs->regs[26];
616 regs->regs[0] = 0; /* Don't deal with this again. */
620 * If there's no signal to deliver, we just put the saved sigmask
623 restore_saved_sigmask();
627 * notification of userspace execution resumption
628 * - triggered by the TIF_WORK_MASK flags
630 asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
631 __u32 thread_info_flags)
637 /* deal with pending signal delivery */
638 if (thread_info_flags & _TIF_SIGPENDING)
641 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
642 clear_thread_flag(TIF_NOTIFY_RESUME);
643 tracehook_notify_resume(regs);
651 static int smp_save_fp_context(struct sigcontext __user *sc)
653 return raw_cpu_has_fpu
654 ? _save_fp_context(sc)
655 : copy_fp_to_sigcontext(sc);
658 static int smp_restore_fp_context(struct sigcontext __user *sc)
660 return raw_cpu_has_fpu
661 ? _restore_fp_context(sc)
662 : copy_fp_from_sigcontext(sc);
664 #endif /* CONFIG_EVA */
667 static int signal_setup(void)
671 /* For now just do the cpu_has_fpu check when the functions are invoked */
672 save_fp_context = smp_save_fp_context;
673 restore_fp_context = smp_restore_fp_context;
676 save_fp_context = _save_fp_context;
677 restore_fp_context = _restore_fp_context;
679 save_fp_context = copy_fp_from_sigcontext;
680 restore_fp_context = copy_fp_to_sigcontext;
682 #endif /* CONFIG_SMP */
684 save_fp_context = copy_fp_from_sigcontext;;
685 restore_fp_context = copy_fp_to_sigcontext;
691 arch_initcall(signal_setup);