diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/sh/kernel/signal.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/sh/kernel/signal.c')
-rw-r--r-- | arch/sh/kernel/signal.c | 607 |
1 files changed, 607 insertions, 0 deletions
diff --git a/arch/sh/kernel/signal.c b/arch/sh/kernel/signal.c new file mode 100644 index 00000000000..06f1b47eded --- /dev/null +++ b/arch/sh/kernel/signal.c @@ -0,0 +1,607 @@ +/* + * linux/arch/sh/kernel/signal.c + * + * Copyright (C) 1991, 1992 Linus Torvalds + * + * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson + * + * SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima + * + */ + +#include <linux/sched.h> +#include <linux/mm.h> +#include <linux/smp.h> +#include <linux/smp_lock.h> +#include <linux/kernel.h> +#include <linux/signal.h> +#include <linux/errno.h> +#include <linux/wait.h> +#include <linux/ptrace.h> +#include <linux/unistd.h> +#include <linux/stddef.h> +#include <linux/tty.h> +#include <linux/personality.h> +#include <linux/binfmts.h> + +#include <asm/ucontext.h> +#include <asm/uaccess.h> +#include <asm/pgtable.h> +#include <asm/cacheflush.h> + +#define DEBUG_SIG 0 + +#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 +sys_sigsuspend(old_sigset_t mask, + unsigned long r5, unsigned long r6, unsigned long r7, + struct pt_regs regs) +{ + 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.regs[0] = -EINTR; + while (1) { + current->state = TASK_INTERRUPTIBLE; + schedule(); + if (do_signal(®s, &saveset)) + return -EINTR; + } +} + +asmlinkage int +sys_rt_sigsuspend(sigset_t *unewset, size_t sigsetsize, + unsigned long r6, unsigned long r7, + struct pt_regs regs) +{ + 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.regs[0] = -EINTR; + while (1) { + current->state = TASK_INTERRUPTIBLE; + schedule(); + if (do_signal(®s, &saveset)) + return -EINTR; + } +} + +asmlinkage int +sys_sigaction(int sig, const struct old_sigaction __user *act, + struct old_sigaction __user *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 __user *uss, stack_t __user *uoss, + unsigned long r6, unsigned long r7, + struct pt_regs regs) +{ + return do_sigaltstack(uss, uoss, regs.regs[15]); +} + + +/* + * Do a signal return; undo the signal stack. + */ + +#define MOVW(n) (0x9300|((n)-2)) /* Move mem word at PC+n to R3 */ +#define TRAP16 0xc310 /* Syscall w/no args (NR in R3) */ +#define OR_R0_R0 0x200b /* or r0,r0 (insert to avoid hardware bug) */ + +struct sigframe +{ + struct sigcontext sc; + unsigned long extramask[_NSIG_WORDS-1]; + u16 retcode[8]; +}; + +struct rt_sigframe +{ + struct siginfo info; + struct ucontext uc; + u16 retcode[8]; +}; + +#ifdef CONFIG_SH_FPU +static inline int restore_sigcontext_fpu(struct sigcontext __user *sc) +{ + struct task_struct *tsk = current; + + if (!(cpu_data->flags & CPU_HAS_FPU)) + return 0; + + set_used_math(); + return __copy_from_user(&tsk->thread.fpu.hard, &sc->sc_fpregs[0], + sizeof(long)*(16*2+2)); +} + +static inline int save_sigcontext_fpu(struct sigcontext __user *sc, + struct pt_regs *regs) +{ + struct task_struct *tsk = current; + + if (!(cpu_data->flags & CPU_HAS_FPU)) + return 0; + + if (!used_math()) { + __put_user(0, &sc->sc_ownedfp); + return 0; + } + + __put_user(1, &sc->sc_ownedfp); + + /* This will cause a "finit" to be triggered by the next + attempted FPU operation by the 'current' process. + */ + clear_used_math(); + + unlazy_fpu(tsk, regs); + return __copy_to_user(&sc->sc_fpregs[0], &tsk->thread.fpu.hard, + sizeof(long)*(16*2+2)); +} +#endif /* CONFIG_SH_FPU */ + +static int +restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *r0_p) +{ + unsigned int err = 0; + +#define COPY(x) err |= __get_user(regs->x, &sc->sc_##x) + COPY(regs[1]); + COPY(regs[2]); COPY(regs[3]); + COPY(regs[4]); COPY(regs[5]); + COPY(regs[6]); COPY(regs[7]); + COPY(regs[8]); COPY(regs[9]); + COPY(regs[10]); COPY(regs[11]); + COPY(regs[12]); COPY(regs[13]); + COPY(regs[14]); COPY(regs[15]); + COPY(gbr); COPY(mach); + COPY(macl); COPY(pr); + COPY(sr); COPY(pc); +#undef COPY + +#ifdef CONFIG_SH_FPU + if (cpu_data->flags & CPU_HAS_FPU) { + int owned_fp; + struct task_struct *tsk = current; + + regs->sr |= SR_FD; /* Release FPU */ + clear_fpu(tsk, regs); + clear_used_math(); + __get_user (owned_fp, &sc->sc_ownedfp); + if (owned_fp) + err |= restore_sigcontext_fpu(sc); + } +#endif + + regs->tra = -1; /* disable syscall checks */ + err |= __get_user(*r0_p, &sc->sc_regs[0]); + return err; +} + +asmlinkage int sys_sigreturn(unsigned long r4, unsigned long r5, + unsigned long r6, unsigned long r7, + struct pt_regs regs) +{ + struct sigframe __user *frame = (struct sigframe __user *)regs.regs[15]; + sigset_t set; + int r0; + + if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) + goto badframe; + + if (__get_user(set.sig[0], &frame->sc.oldmask) + || (_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(®s, &frame->sc, &r0)) + goto badframe; + return r0; + +badframe: + force_sig(SIGSEGV, current); + return 0; +} + +asmlinkage int sys_rt_sigreturn(unsigned long r4, unsigned long r5, + unsigned long r6, unsigned long r7, + struct pt_regs regs) +{ + struct rt_sigframe __user *frame = (struct rt_sigframe __user *)regs.regs[15]; + sigset_t set; + stack_t st; + int r0; + + 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_lock_irq(¤t->sighand->siglock); + current->blocked = set; + recalc_sigpending(); + spin_unlock_irq(¤t->sighand->siglock); + + if (restore_sigcontext(®s, &frame->uc.uc_mcontext, &r0)) + goto badframe; + + if (__copy_from_user(&st, &frame->uc.uc_stack, sizeof(st))) + goto badframe; + /* It is more difficult to avoid calling this function than to + call it and ignore errors. */ + do_sigaltstack(&st, NULL, regs.regs[15]); + + return r0; + +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(regs[0]); COPY(regs[1]); + COPY(regs[2]); COPY(regs[3]); + COPY(regs[4]); COPY(regs[5]); + COPY(regs[6]); COPY(regs[7]); + COPY(regs[8]); COPY(regs[9]); + COPY(regs[10]); COPY(regs[11]); + COPY(regs[12]); COPY(regs[13]); + COPY(regs[14]); COPY(regs[15]); + COPY(gbr); COPY(mach); + COPY(macl); COPY(pr); + COPY(sr); COPY(pc); +#undef COPY + +#ifdef CONFIG_SH_FPU + err |= save_sigcontext_fpu(sc, regs); +#endif + + /* non-iBCS2 extensions.. */ + err |= __put_user(mask, &sc->oldmask); + + return err; +} + +/* + * Determine which stack to use.. + */ +static inline void __user * +get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size) +{ + if (ka->sa.sa_flags & SA_ONSTACK) { + if (sas_ss_flags(sp) == 0) + sp = current->sas_ss_sp + current->sas_ss_size; + } + + return (void __user *)((sp - frame_size) & -8ul); +} + +static void setup_frame(int sig, struct k_sigaction *ka, + sigset_t *set, struct pt_regs *regs) +{ + struct sigframe __user *frame; + int err = 0; + int signal; + + frame = get_sigframe(ka, regs->regs[15], sizeof(*frame)); + + if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) + goto give_sigsegv; + + signal = current_thread_info()->exec_domain + && current_thread_info()->exec_domain->signal_invmap + && sig < 32 + ? current_thread_info()->exec_domain->signal_invmap[sig] + : sig; + + err |= setup_sigcontext(&frame->sc, regs, set->sig[0]); + + if (_NSIG_WORDS > 1) { + err |= __copy_to_user(frame->extramask, &set->sig[1], + sizeof(frame->extramask)); + } + + /* Set up to return from userspace. If provided, use a stub + already in userspace. */ + if (ka->sa.sa_flags & SA_RESTORER) { + regs->pr = (unsigned long) ka->sa.sa_restorer; + } else { + /* Generate return code (system call to sigreturn) */ + err |= __put_user(MOVW(7), &frame->retcode[0]); + err |= __put_user(TRAP16, &frame->retcode[1]); + err |= __put_user(OR_R0_R0, &frame->retcode[2]); + err |= __put_user(OR_R0_R0, &frame->retcode[3]); + err |= __put_user(OR_R0_R0, &frame->retcode[4]); + err |= __put_user(OR_R0_R0, &frame->retcode[5]); + err |= __put_user(OR_R0_R0, &frame->retcode[6]); + err |= __put_user((__NR_sigreturn), &frame->retcode[7]); + regs->pr = (unsigned long) frame->retcode; + } + + if (err) + goto give_sigsegv; + + /* Set up registers for signal handler */ + regs->regs[15] = (unsigned long) frame; + regs->regs[4] = signal; /* Arg for signal handler */ + regs->regs[5] = 0; + regs->regs[6] = (unsigned long) &frame->sc; + regs->pc = (unsigned long) ka->sa.sa_handler; + + set_fs(USER_DS); + +#if DEBUG_SIG + printk("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n", + current->comm, current->pid, frame, regs->pc, regs->pr); +#endif + + flush_cache_sigtramp(regs->pr); + if ((-regs->pr & (L1_CACHE_BYTES-1)) < sizeof(frame->retcode)) + flush_cache_sigtramp(regs->pr + L1_CACHE_BYTES); + 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 __user *frame; + int err = 0; + int signal; + + frame = get_sigframe(ka, regs->regs[15], sizeof(*frame)); + + if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) + goto give_sigsegv; + + signal = current_thread_info()->exec_domain + && current_thread_info()->exec_domain->signal_invmap + && sig < 32 + ? current_thread_info()->exec_domain->signal_invmap[sig] + : sig; + + err |= copy_siginfo_to_user(&frame->info, info); + + /* 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(regs->regs[15]), + &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)); + + /* Set up to return from userspace. If provided, use a stub + already in userspace. */ + if (ka->sa.sa_flags & SA_RESTORER) { + regs->pr = (unsigned long) ka->sa.sa_restorer; + } else { + /* Generate return code (system call to rt_sigreturn) */ + err |= __put_user(MOVW(7), &frame->retcode[0]); + err |= __put_user(TRAP16, &frame->retcode[1]); + err |= __put_user(OR_R0_R0, &frame->retcode[2]); + err |= __put_user(OR_R0_R0, &frame->retcode[3]); + err |= __put_user(OR_R0_R0, &frame->retcode[4]); + err |= __put_user(OR_R0_R0, &frame->retcode[5]); + err |= __put_user(OR_R0_R0, &frame->retcode[6]); + err |= __put_user((__NR_rt_sigreturn), &frame->retcode[7]); + regs->pr = (unsigned long) frame->retcode; + } + + if (err) + goto give_sigsegv; + + /* Set up registers for signal handler */ + regs->regs[15] = (unsigned long) frame; + regs->regs[4] = signal; /* Arg for signal handler */ + regs->regs[5] = (unsigned long) &frame->info; + regs->regs[6] = (unsigned long) &frame->uc; + regs->pc = (unsigned long) ka->sa.sa_handler; + + set_fs(USER_DS); + +#if DEBUG_SIG + printk("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n", + current->comm, current->pid, frame, regs->pc, regs->pr); +#endif + + flush_cache_sigtramp(regs->pr); + if ((-regs->pr & (L1_CACHE_BYTES-1)) < sizeof(frame->retcode)) + flush_cache_sigtramp(regs->pr + L1_CACHE_BYTES); + return; + +give_sigsegv: + force_sigsegv(sig, current); +} + +/* + * OK, we're invoking a handler + */ + +static void +handle_signal(unsigned long sig, struct k_sigaction *ka, siginfo_t *info, + sigset_t *oldset, struct pt_regs *regs) +{ + /* Are we from a system call? */ + if (regs->tra >= 0) { + /* If so, check system call restarting.. */ + switch (regs->regs[0]) { + case -ERESTARTNOHAND: + regs->regs[0] = -EINTR; + break; + + case -ERESTARTSYS: + if (!(ka->sa.sa_flags & SA_RESTART)) { + regs->regs[0] = -EINTR; + break; + } + /* fallthrough */ + case -ERESTARTNOINTR: + regs->pc -= 2; + } + } else { + /* gUSA handling */ +#ifdef CONFIG_PREEMPT + unsigned long flags; + + local_irq_save(flags); +#endif + if (regs->regs[15] >= 0xc0000000) { + int offset = (int)regs->regs[15]; + + /* Reset stack pointer: clear critical region mark */ + regs->regs[15] = regs->regs[1]; + if (regs->pc < regs->regs[0]) + /* Go to rewind point #1 */ + regs->pc = regs->regs[0] + offset - 2; + } +#ifdef CONFIG_PREEMPT + local_irq_restore(flags); +#endif + } + + /* 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_ONESHOT) + ka->sa.sa_handler = SIG_DFL; + + 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. + * + * Note that we go through the signals twice: once to check the signals that + * the kernel can handle, and then we build all the user-level signal handling + * stack-frames in one go after that. + */ +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 (!user_mode(regs)) + return 1; + + if (try_to_freeze(0)) + goto no_signal; + + 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, &ka, &info, oldset, regs); + return 1; + } + + no_signal: + /* Did we come from a system call? */ + if (regs->tra >= 0) { + /* Restart the system call - no handlers present */ + if (regs->regs[0] == -ERESTARTNOHAND || + regs->regs[0] == -ERESTARTSYS || + regs->regs[0] == -ERESTARTNOINTR || + regs->regs[0] == -ERESTART_RESTARTBLOCK) { + regs->pc -= 2; + } + } + return 0; +} |