diff options
Diffstat (limited to 'arch/m32r/kernel/signal.c')
-rw-r--r-- | arch/m32r/kernel/signal.c | 335 |
1 files changed, 335 insertions, 0 deletions
diff --git a/arch/m32r/kernel/signal.c b/arch/m32r/kernel/signal.c new file mode 100644 index 000000000..1c81e24fd --- /dev/null +++ b/arch/m32r/kernel/signal.c @@ -0,0 +1,335 @@ +/* + * linux/arch/m32r/kernel/signal.c + * + * Copyright (c) 2003 Hitoshi Yamamoto + * + * Taken from i386 version. + * Copyright (C) 1991, 1992 Linus Torvalds + * + * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson + * 2000-06-20 Pentium III FXSR, SSE support by Gareth Hughes + */ + +#include <linux/sched.h> +#include <linux/mm.h> +#include <linux/smp.h> +#include <linux/kernel.h> +#include <linux/signal.h> +#include <linux/errno.h> +#include <linux/wait.h> +#include <linux/unistd.h> +#include <linux/stddef.h> +#include <linux/personality.h> +#include <linux/tracehook.h> +#include <asm/cacheflush.h> +#include <asm/ucontext.h> +#include <asm/uaccess.h> + +#define DEBUG_SIG 0 + +/* + * Do a signal return; undo the signal stack. + */ + +struct rt_sigframe +{ + int sig; + struct siginfo __user *pinfo; + void __user *puc; + struct siginfo info; + struct ucontext uc; +// struct _fpstate fpstate; +}; + +static int +restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, + int *r0_p) +{ + unsigned int err = 0; + + /* Always make any pending restarted system calls return -EINTR */ + current->restart_block.fn = do_no_restart_syscall; + +#define COPY(x) err |= __get_user(regs->x, &sc->sc_##x) + COPY(r4); + COPY(r5); + COPY(r6); + COPY(pt_regs); + /* COPY(r0); Skip r0 */ + COPY(r1); + COPY(r2); + COPY(r3); + COPY(r7); + COPY(r8); + COPY(r9); + COPY(r10); + COPY(r11); + COPY(r12); + COPY(acc0h); + COPY(acc0l); + COPY(acc1h); /* ISA_DSP_LEVEL2 only */ + COPY(acc1l); /* ISA_DSP_LEVEL2 only */ + COPY(psw); + COPY(bpc); + COPY(bbpsw); + COPY(bbpc); + COPY(spu); + COPY(fp); + COPY(lr); + COPY(spi); +#undef COPY + + regs->syscall_nr = -1; /* disable syscall checks */ + err |= __get_user(*r0_p, &sc->sc_r0); + + return err; +} + +asmlinkage int +sys_rt_sigreturn(unsigned long r0, unsigned long r1, + unsigned long r2, unsigned long r3, unsigned long r4, + unsigned long r5, unsigned long r6, struct pt_regs *regs) +{ + struct rt_sigframe __user *frame = (struct rt_sigframe __user *)regs->spu; + sigset_t set; + int result; + + if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) + goto badframe; + if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) + goto badframe; + + set_current_blocked(&set); + + if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &result)) + goto badframe; + + if (restore_altstack(&frame->uc.uc_stack)) + goto badframe; + + return result; + +badframe: + force_sig(SIGSEGV, current); + return 0; +} + +/* + * Set up a signal frame. + */ + +static int +setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, + unsigned long mask) +{ + int err = 0; + +#define COPY(x) err |= __put_user(regs->x, &sc->sc_##x) + COPY(r4); + COPY(r5); + COPY(r6); + COPY(pt_regs); + COPY(r0); + COPY(r1); + COPY(r2); + COPY(r3); + COPY(r7); + COPY(r8); + COPY(r9); + COPY(r10); + COPY(r11); + COPY(r12); + COPY(acc0h); + COPY(acc0l); + COPY(acc1h); /* ISA_DSP_LEVEL2 only */ + COPY(acc1l); /* ISA_DSP_LEVEL2 only */ + COPY(psw); + COPY(bpc); + COPY(bbpsw); + COPY(bbpc); + COPY(spu); + COPY(fp); + COPY(lr); + COPY(spi); +#undef COPY + + err |= __put_user(mask, &sc->oldmask); + + return err; +} + +/* + * Determine which stack to use.. + */ +static inline void __user * +get_sigframe(struct ksignal *ksig, unsigned long sp, size_t frame_size) +{ + return (void __user *)((sigsp(sp, ksig) - frame_size) & -8ul); +} + +static int setup_rt_frame(struct ksignal *ksig, sigset_t *set, + struct pt_regs *regs) +{ + struct rt_sigframe __user *frame; + int err = 0; + int sig = ksig->sig; + + frame = get_sigframe(ksig, regs->spu, sizeof(*frame)); + + if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) + return -EFAULT; + + err |= __put_user(sig, &frame->sig); + if (err) + return -EFAULT; + + err |= __put_user(&frame->info, &frame->pinfo); + err |= __put_user(&frame->uc, &frame->puc); + err |= copy_siginfo_to_user(&frame->info, &ksig->info); + if (err) + return -EFAULT; + + /* Create the ucontext. */ + err |= __put_user(0, &frame->uc.uc_flags); + err |= __put_user(0, &frame->uc.uc_link); + err |= __save_altstack(&frame->uc.uc_stack, regs->spu); + err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, set->sig[0]); + err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); + if (err) + return -EFAULT; + + /* Set up to return from userspace. */ + regs->lr = (unsigned long)ksig->ka.sa.sa_restorer; + + /* Set up registers for signal handler */ + regs->spu = (unsigned long)frame; + regs->r0 = sig; /* Arg for signal handler */ + regs->r1 = (unsigned long)&frame->info; + regs->r2 = (unsigned long)&frame->uc; + regs->bpc = (unsigned long)ksig->ka.sa.sa_handler; + +#if DEBUG_SIG + printk("SIG deliver (%s:%d): sp=%p pc=%p\n", + current->comm, current->pid, frame, regs->pc); +#endif + + return 0; +} + +static int prev_insn(struct pt_regs *regs) +{ + u16 inst; + if (get_user(inst, (u16 __user *)(regs->bpc - 2))) + return -EFAULT; + if ((inst & 0xfff0) == 0x10f0) /* trap ? */ + regs->bpc -= 2; + else + regs->bpc -= 4; + regs->syscall_nr = -1; + return 0; +} + +/* + * OK, we're invoking a handler + */ + +static void +handle_signal(struct ksignal *ksig, struct pt_regs *regs) +{ + int ret; + + /* Are we from a system call? */ + if (regs->syscall_nr >= 0) { + /* If so, check system call restarting.. */ + switch (regs->r0) { + case -ERESTART_RESTARTBLOCK: + case -ERESTARTNOHAND: + regs->r0 = -EINTR; + break; + + case -ERESTARTSYS: + if (!(ksig->ka.sa.sa_flags & SA_RESTART)) { + regs->r0 = -EINTR; + break; + } + /* fallthrough */ + case -ERESTARTNOINTR: + regs->r0 = regs->orig_r0; + if (prev_insn(regs) < 0) + return; + } + } + + /* Set up the stack frame */ + ret = setup_rt_frame(ksig, sigmask_to_save(), regs); + + signal_setup_done(ret, ksig, 0); +} + +/* + * 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. + */ +static void do_signal(struct pt_regs *regs) +{ + struct ksignal ksig; + + /* + * 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 (!user_mode(regs)) + return; + + if (get_signal(&ksig)) { + /* Re-enable any watchpoints before delivering the + * signal to user space. The processor register will + * have been cleared if the watchpoint triggered + * inside the kernel. + */ + + /* Whee! Actually deliver the signal. */ + handle_signal(&ksig, regs); + + return; + } + + /* Did we come from a system call? */ + if (regs->syscall_nr >= 0) { + /* Restart the system call - no handlers present */ + if (regs->r0 == -ERESTARTNOHAND || + regs->r0 == -ERESTARTSYS || + regs->r0 == -ERESTARTNOINTR) { + regs->r0 = regs->orig_r0; + prev_insn(regs); + } else if (regs->r0 == -ERESTART_RESTARTBLOCK){ + regs->r0 = regs->orig_r0; + regs->r7 = __NR_restart_syscall; + prev_insn(regs); + } + } + restore_saved_sigmask(); +} + +/* + * notification of userspace execution resumption + * - triggered by current->work.notify_resume + */ +void do_notify_resume(struct pt_regs *regs, __u32 thread_info_flags) +{ + /* Pending single-step? */ + if (thread_info_flags & _TIF_SINGLESTEP) + clear_thread_flag(TIF_SINGLESTEP); + + /* deal with pending signal delivery */ + if (thread_info_flags & _TIF_SIGPENDING) + do_signal(regs); + + if (thread_info_flags & _TIF_NOTIFY_RESUME) { + clear_thread_flag(TIF_NOTIFY_RESUME); + tracehook_notify_resume(regs); + } +} |