diff options
Diffstat (limited to 'arch/h8300/kernel/signal.c')
| -rw-r--r-- | arch/h8300/kernel/signal.c | 552 |
1 files changed, 552 insertions, 0 deletions
diff --git a/arch/h8300/kernel/signal.c b/arch/h8300/kernel/signal.c new file mode 100644 index 00000000000..a4799d633ef --- /dev/null +++ b/arch/h8300/kernel/signal.c @@ -0,0 +1,552 @@ +/* + * linux/arch/h8300/kernel/signal.c + * + * Copyright (C) 1991, 1992 Linus Torvalds + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of this archive + * for more details. + */ + +/* + * uClinux H8/300 support by Yoshinori Sato <ysato@users.sourceforge.jp> + * and David McCullough <davidm@snapgear.com> + * + * Based on + * Linux/m68k by Hamish Macdonald + */ + +/* + * ++roman (07/09/96): implemented signal stacks (specially for tosemu on + * Atari :-) Current limitation: Only one sigstack can be active at one time. + * If a second signal with SA_ONSTACK set arrives while working on a sigstack, + * SA_ONSTACK is ignored. This behaviour avoids lots of trouble with nested + * signal handlers! + */ + +#include <linux/sched.h> +#include <linux/mm.h> +#include <linux/kernel.h> +#include <linux/signal.h> +#include <linux/syscalls.h> +#include <linux/errno.h> +#include <linux/wait.h> +#include <linux/ptrace.h> +#include <linux/unistd.h> +#include <linux/stddef.h> +#include <linux/highuid.h> +#include <linux/personality.h> +#include <linux/tty.h> +#include <linux/binfmts.h> +#include <linux/suspend.h> + +#include <asm/setup.h> +#include <asm/uaccess.h> +#include <asm/pgtable.h> +#include <asm/traps.h> +#include <asm/ucontext.h> + +#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) + +asmlinkage int do_signal(struct pt_regs *regs, sigset_t *oldset); + +/* + * Atomically swap in the new signal mask, and wait for a signal. + */ +asmlinkage int do_sigsuspend(struct pt_regs *regs) +{ + old_sigset_t mask = regs->er3; + sigset_t saveset; + + mask &= _BLOCKABLE; + spin_lock_irq(¤t->sighand->siglock); + saveset = current->blocked; + siginitset(¤t->blocked, mask); + recalc_sigpending(); + spin_unlock_irq(¤t->sighand->siglock); + + regs->er0 = -EINTR; + while (1) { + current->state = TASK_INTERRUPTIBLE; + schedule(); + if (do_signal(regs, &saveset)) + return -EINTR; + } +} + +asmlinkage int +do_rt_sigsuspend(struct pt_regs *regs) +{ + sigset_t *unewset = (sigset_t *)regs->er1; + size_t sigsetsize = (size_t)regs->er2; + sigset_t saveset, newset; + + /* XXX: Don't preclude handling different sized sigset_t's. */ + if (sigsetsize != sizeof(sigset_t)) + return -EINVAL; + + if (copy_from_user(&newset, unewset, sizeof(newset))) + return -EFAULT; + sigdelsetmask(&newset, ~_BLOCKABLE); + + spin_lock_irq(¤t->sighand->siglock); + saveset = current->blocked; + current->blocked = newset; + recalc_sigpending(); + spin_unlock_irq(¤t->sighand->siglock); + + regs->er0 = -EINTR; + while (1) { + current->state = TASK_INTERRUPTIBLE; + schedule(); + if (do_signal(regs, &saveset)) + return -EINTR; + } +} + +asmlinkage int +sys_sigaction(int sig, const struct old_sigaction *act, + struct old_sigaction *oact) +{ + struct k_sigaction new_ka, old_ka; + int ret; + + if (act) { + old_sigset_t mask; + if (!access_ok(VERIFY_READ, act, sizeof(*act)) || + __get_user(new_ka.sa.sa_handler, &act->sa_handler) || + __get_user(new_ka.sa.sa_restorer, &act->sa_restorer)) + return -EFAULT; + __get_user(new_ka.sa.sa_flags, &act->sa_flags); + __get_user(mask, &act->sa_mask); + siginitset(&new_ka.sa.sa_mask, mask); + } + + ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); + + if (!ret && oact) { + if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || + __put_user(old_ka.sa.sa_handler, &oact->sa_handler) || + __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer)) + return -EFAULT; + __put_user(old_ka.sa.sa_flags, &oact->sa_flags); + __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask); + } + + return ret; +} + +asmlinkage int +sys_sigaltstack(const stack_t *uss, stack_t *uoss) +{ + return do_sigaltstack(uss, uoss, rdusp()); +} + + +/* + * Do a signal return; undo the signal stack. + * + * Keep the return code on the stack quadword aligned! + * That makes the cache flush below easier. + */ + +struct sigframe +{ + long dummy_er0; + long dummy_vector; +#if defined(CONFIG_CPU_H8S) + short dummy_exr; +#endif + long dummy_pc; + char *pretcode; + unsigned char retcode[8]; + unsigned long extramask[_NSIG_WORDS-1]; + struct sigcontext sc; + int sig; +} __attribute__((aligned(2),packed)); + +struct rt_sigframe +{ + long dummy_er0; + long dummy_vector; +#if defined(CONFIG_CPU_H8S) + short dummy_exr; +#endif + long dummy_pc; + char *pretcode; + struct siginfo *pinfo; + void *puc; + unsigned char retcode[8]; + struct siginfo info; + struct ucontext uc; + int sig; +} __attribute__((aligned(2),packed)); + +static inline int +restore_sigcontext(struct pt_regs *regs, struct sigcontext *usc, + int *pd0) +{ + int err = 0; + unsigned int ccr; + unsigned int usp; + unsigned int er0; + + /* Always make any pending restarted system calls return -EINTR */ + current_thread_info()->restart_block.fn = do_no_restart_syscall; + +#define COPY(r) err |= __get_user(regs->r, &usc->sc_##r) /* restore passed registers */ + COPY(er1); + COPY(er2); + COPY(er3); + COPY(er5); + COPY(pc); + ccr = regs->ccr & 0x10; + COPY(ccr); +#undef COPY + regs->ccr &= 0xef; + regs->ccr |= ccr; + regs->orig_er0 = -1; /* disable syscall checks */ + err |= __get_user(usp, &usc->sc_usp); + wrusp(usp); + + err |= __get_user(er0, &usc->sc_er0); + *pd0 = er0; + return err; +} + +asmlinkage int do_sigreturn(unsigned long __unused,...) +{ + struct pt_regs *regs = (struct pt_regs *) (&__unused - 1); + unsigned long usp = rdusp(); + struct sigframe *frame = (struct sigframe *)(usp - 4); + sigset_t set; + int er0; + + if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) + goto badframe; + if (__get_user(set.sig[0], &frame->sc.sc_mask) || + (_NSIG_WORDS > 1 && + __copy_from_user(&set.sig[1], &frame->extramask, + sizeof(frame->extramask)))) + goto badframe; + + sigdelsetmask(&set, ~_BLOCKABLE); + spin_lock_irq(¤t->sighand->siglock); + current->blocked = set; + recalc_sigpending(); + spin_unlock_irq(¤t->sighand->siglock); + + if (restore_sigcontext(regs, &frame->sc, &er0)) + goto badframe; + return er0; + +badframe: + force_sig(SIGSEGV, current); + return 0; +} + +asmlinkage int do_rt_sigreturn(unsigned long __unused,...) +{ + struct pt_regs *regs = (struct pt_regs *) &__unused; + unsigned long usp = rdusp(); + struct rt_sigframe *frame = (struct rt_sigframe *)(usp - 4); + sigset_t set; + int er0; + + if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) + goto badframe; + if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) + goto badframe; + + sigdelsetmask(&set, ~_BLOCKABLE); + spin_unlock_irq(¤t->sighand->siglock); + current->blocked = set; + recalc_sigpending(); + spin_lock_irq(¤t->sighand->siglock); + + if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &er0)) + goto badframe; + + if (do_sigaltstack(&frame->uc.uc_stack, NULL, usp) == -EFAULT) + goto badframe; + + return er0; + +badframe: + force_sig(SIGSEGV, current); + return 0; +} + +static int setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, + unsigned long mask) +{ + int err = 0; + + err |= __put_user(regs->er0, &sc->sc_er0); + err |= __put_user(regs->er1, &sc->sc_er1); + err |= __put_user(regs->er2, &sc->sc_er2); + err |= __put_user(regs->er3, &sc->sc_er3); + err |= __put_user(regs->er4, &sc->sc_er4); + err |= __put_user(regs->er5, &sc->sc_er5); + err |= __put_user(regs->er6, &sc->sc_er6); + err |= __put_user(rdusp(), &sc->sc_usp); + err |= __put_user(regs->pc, &sc->sc_pc); + err |= __put_user(regs->ccr, &sc->sc_ccr); + err |= __put_user(mask, &sc->sc_mask); + + return err; +} + +static inline void * +get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size) +{ + unsigned long usp; + + /* Default to using normal stack. */ + usp = rdusp(); + + /* This is the X/Open sanctioned signal stack switching. */ + if (ka->sa.sa_flags & SA_ONSTACK) { + if (!on_sig_stack(usp)) + usp = current->sas_ss_sp + current->sas_ss_size; + } + return (void *)((usp - frame_size) & -8UL); +} + +static void setup_frame (int sig, struct k_sigaction *ka, + sigset_t *set, struct pt_regs *regs) +{ + struct sigframe *frame; + int err = 0; + int usig; + unsigned char *ret; + + frame = get_sigframe(ka, regs, sizeof(*frame)); + + if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) + goto give_sigsegv; + + usig = current_thread_info()->exec_domain + && current_thread_info()->exec_domain->signal_invmap + && sig < 32 + ? current_thread_info()->exec_domain->signal_invmap[sig] + : sig; + + err |= __put_user(usig, &frame->sig); + if (err) + goto give_sigsegv; + + err |= setup_sigcontext(&frame->sc, regs, set->sig[0]); + if (err) + goto give_sigsegv; + + if (_NSIG_WORDS > 1) { + err |= copy_to_user(frame->extramask, &set->sig[1], + sizeof(frame->extramask)); + if (err) + goto give_sigsegv; + } + + ret = frame->retcode; + if (ka->sa.sa_flags & SA_RESTORER) + ret = (unsigned char *)(ka->sa.sa_restorer); + else { + /* sub.l er0,er0; mov.b #__NR_sigreturn,r0l; trapa #0 */ + err != __put_user(0x1a80f800 + (__NR_sigreturn & 0xff), + (unsigned long *)(frame->retcode + 0)); + err |= __put_user(0x5700, (unsigned short *)(frame->retcode + 4)); + } + + /* Set up to return from userspace. */ + err |= __put_user(ret, &frame->pretcode); + + if (err) + goto give_sigsegv; + + /* Set up registers for signal handler */ + wrusp ((unsigned long) frame); + regs->pc = (unsigned long) ka->sa.sa_handler; + regs->er0 = (current_thread_info()->exec_domain + && current_thread_info()->exec_domain->signal_invmap + && sig < 32 + ? current_thread_info()->exec_domain->signal_invmap[sig] + : sig); + regs->er1 = (unsigned long)&(frame->sc); + regs->er5 = current->mm->start_data; /* GOT base */ + + return; + +give_sigsegv: + force_sigsegv(sig, current); +} + +static void setup_rt_frame (int sig, struct k_sigaction *ka, siginfo_t *info, + sigset_t *set, struct pt_regs *regs) +{ + struct rt_sigframe *frame; + int err = 0; + int usig; + unsigned char *ret; + + frame = get_sigframe(ka, regs, sizeof(*frame)); + + if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) + goto give_sigsegv; + + usig = current_thread_info()->exec_domain + && current_thread_info()->exec_domain->signal_invmap + && sig < 32 + ? current_thread_info()->exec_domain->signal_invmap[sig] + : sig; + + err |= __put_user(usig, &frame->sig); + if (err) + goto give_sigsegv; + + err |= __put_user(&frame->info, &frame->pinfo); + err |= __put_user(&frame->uc, &frame->puc); + err |= copy_siginfo_to_user(&frame->info, info); + if (err) + goto give_sigsegv; + + /* Create the ucontext. */ + err |= __put_user(0, &frame->uc.uc_flags); + err |= __put_user(0, &frame->uc.uc_link); + err |= __put_user((void *)current->sas_ss_sp, + &frame->uc.uc_stack.ss_sp); + err |= __put_user(sas_ss_flags(rdusp()), + &frame->uc.uc_stack.ss_flags); + err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size); + err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, set->sig[0]); + err |= copy_to_user (&frame->uc.uc_sigmask, set, sizeof(*set)); + if (err) + goto give_sigsegv; + + /* Set up to return from userspace. */ + ret = frame->retcode; + if (ka->sa.sa_flags & SA_RESTORER) + ret = (unsigned char *)(ka->sa.sa_restorer); + else { + /* sub.l er0,er0; mov.b #__NR_sigreturn,r0l; trapa #0 */ + err != __put_user(0x1a80f800 + (__NR_sigreturn & 0xff), + (unsigned long *)(frame->retcode + 0)); + err |= __put_user(0x5700, (unsigned short *)(frame->retcode + 4)); + } + err |= __put_user(ret, &frame->pretcode); + + if (err) + goto give_sigsegv; + + /* Set up registers for signal handler */ + wrusp ((unsigned long) frame); + regs->pc = (unsigned long) ka->sa.sa_handler; + regs->er0 = (current_thread_info()->exec_domain + && current_thread_info()->exec_domain->signal_invmap + && sig < 32 + ? current_thread_info()->exec_domain->signal_invmap[sig] + : sig); + regs->er1 = (unsigned long)&(frame->info); + regs->er2 = (unsigned long)&frame->uc; + regs->er5 = current->mm->start_data; /* GOT base */ + + return; + +give_sigsegv: + force_sigsegv(sig, current); +} + +/* + * OK, we're invoking a handler + */ +static void +handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka, + sigset_t *oldset, struct pt_regs * regs) +{ + /* are we from a system call? */ + if (regs->orig_er0 >= 0) { + switch (regs->er0) { + case -ERESTART_RESTARTBLOCK: + case -ERESTARTNOHAND: + regs->er0 = -EINTR; + break; + + case -ERESTARTSYS: + if (!(ka->sa.sa_flags & SA_RESTART)) { + regs->er0 = -EINTR; + break; + } + /* fallthrough */ + case -ERESTARTNOINTR: + regs->er0 = regs->orig_er0; + regs->pc -= 2; + } + } + + /* set up the stack frame */ + if (ka->sa.sa_flags & SA_SIGINFO) + setup_rt_frame(sig, ka, info, oldset, regs); + else + setup_frame(sig, ka, oldset, regs); + + if (!(ka->sa.sa_flags & SA_NODEFER)) { + spin_lock_irq(¤t->sighand->siglock); + sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask); + sigaddset(¤t->blocked,sig); + recalc_sigpending(); + spin_unlock_irq(¤t->sighand->siglock); + } +} + +/* + * Note that 'init' is a special process: it doesn't get signals it doesn't + * want to handle. Thus you cannot kill init even with a SIGKILL even by + * mistake. + */ +asmlinkage int do_signal(struct pt_regs *regs, sigset_t *oldset) +{ + siginfo_t info; + int signr; + struct k_sigaction ka; + + /* + * We want the common case to go fast, which + * is why we may in certain cases get here from + * kernel mode. Just return without doing anything + * if so. + */ + if ((regs->ccr & 0x10)) + return 1; + + if (current->flags & PF_FREEZE) { + refrigerator(0); + goto no_signal; + } + + current->thread.esp0 = (unsigned long) regs; + + if (!oldset) + oldset = ¤t->blocked; + + signr = get_signal_to_deliver(&info, &ka, regs, NULL); + if (signr > 0) { + /* Whee! Actually deliver the signal. */ + handle_signal(signr, &info, &ka, oldset, regs); + return 1; + } + no_signal: + /* Did we come from a system call? */ + if (regs->orig_er0 >= 0) { + /* Restart the system call - no handlers present */ + if (regs->er0 == -ERESTARTNOHAND || + regs->er0 == -ERESTARTSYS || + regs->er0 == -ERESTARTNOINTR) { + regs->er0 = regs->orig_er0; + regs->pc -= 2; + } + if (regs->er0 == -ERESTART_RESTARTBLOCK){ + regs->er0 = __NR_restart_syscall; + regs->pc -= 2; + } + } + return 0; +} |