/* * arch/v850/kernel/signal.c -- Signal handling * *  Copyright (C) 2001,02,03  NEC Electronics Corporation *  Copyright (C) 2001,02,03  Miles Bader <miles@gnu.org> *  Copyright (C) 1999,2000,2002  Niibe Yutaka & Kaz Kojima *  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. * * 1997-11-28  Modified for POSIX.1b signals by Richard Henderson * * This file was derived from the sh version, arch/sh/kernel/signal.c */#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/personality.h>#include <linux/tty.h>#include <asm/ucontext.h>#include <asm/uaccess.h>#include <asm/pgtable.h>#include <asm/pgalloc.h>#include <asm/thread_info.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 intsys_sigsuspend(old_sigset_t mask, struct pt_regs *regs){	sigset_t saveset;	mask &= _BLOCKABLE;	spin_lock_irq(&current->sighand->siglock);	saveset = current->blocked;	siginitset(&current->blocked, mask);	recalc_sigpending();	spin_unlock_irq(&current->sighand->siglock);	regs->gpr[GPR_RVAL] = -EINTR;	while (1) {		current->state = TASK_INTERRUPTIBLE;		schedule();		if (do_signal(regs, &saveset))			return -EINTR;	}}asmlinkage intsys_rt_sigsuspend(sigset_t *unewset, size_t sigsetsize,		  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(&current->sighand->siglock);	saveset = current->blocked;	current->blocked = newset;	recalc_sigpending();	spin_unlock_irq(&current->sighand->siglock);	regs->gpr[GPR_RVAL] = -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 intsys_sigaltstack(const stack_t *uss, stack_t *uoss,		struct pt_regs *regs){	return do_sigaltstack(uss, uoss, regs->gpr[GPR_SP]);}/* * Do a signal return; undo the signal stack. */struct sigframe{	struct sigcontext sc;	unsigned long extramask[_NSIG_WORDS-1];	unsigned long tramp[2];	/* signal trampoline */};struct rt_sigframe{	struct siginfo info;	struct ucontext uc;	unsigned long tramp[2];	/* signal trampoline */};static intrestore_sigcontext(struct pt_regs *regs, struct sigcontext *sc, int *rval_p){	unsigned int err = 0;#define COPY(x)		err |= __get_user(regs->x, &sc->regs.x)	COPY(gpr[0]);	COPY(gpr[1]);	COPY(gpr[2]);	COPY(gpr[3]);	COPY(gpr[4]);	COPY(gpr[5]);	COPY(gpr[6]);	COPY(gpr[7]);	COPY(gpr[8]);	COPY(gpr[9]);	COPY(gpr[10]);	COPY(gpr[11]);	COPY(gpr[12]);	COPY(gpr[13]);	COPY(gpr[14]);	COPY(gpr[15]);	COPY(gpr[16]);	COPY(gpr[17]);	COPY(gpr[18]);	COPY(gpr[19]);	COPY(gpr[20]);	COPY(gpr[21]);	COPY(gpr[22]);	COPY(gpr[23]);	COPY(gpr[24]);	COPY(gpr[25]);	COPY(gpr[26]);	COPY(gpr[27]);	COPY(gpr[28]);	COPY(gpr[29]);	COPY(gpr[30]);	COPY(gpr[31]);	COPY(pc);	COPY(psw);	COPY(ctpc);	COPY(ctpsw);	COPY(ctbp);#undef COPY	return err;}asmlinkage int sys_sigreturn(struct pt_regs *regs){	struct sigframe *frame = (struct sigframe *)regs->gpr[GPR_SP];	sigset_t set;	int rval;	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(&current->sighand->siglock);	current->blocked = set;	recalc_sigpending();	spin_unlock_irq(&current->sighand->siglock);	if (restore_sigcontext(regs, &frame->sc, &rval))		goto badframe;	return rval;badframe:	force_sig(SIGSEGV, current);	return 0;}asmlinkage int sys_rt_sigreturn(struct pt_regs *regs){	struct rt_sigframe *frame = (struct rt_sigframe *)regs->gpr[GPR_SP];	sigset_t set;	stack_t st;	int rval;	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(&current->sighand->siglock);	current->blocked = set;	recalc_sigpending();	spin_unlock_irq(&current->sighand->siglock);	if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &rval))		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->gpr[GPR_SP]);	return rval;badframe:	force_sig(SIGSEGV, current);	return 0;}	/* * Set up a signal frame. */static intsetup_sigcontext(struct sigcontext *sc, struct pt_regs *regs,		 unsigned long mask){	int err = 0;#define COPY(x)		err |= __put_user(regs->x, &sc->regs.x)	COPY(gpr[0]);	COPY(gpr[1]);	COPY(gpr[2]);	COPY(gpr[3]);	COPY(gpr[4]);	COPY(gpr[5]);	COPY(gpr[6]);	COPY(gpr[7]);	COPY(gpr[8]);	COPY(gpr[9]);	COPY(gpr[10]);	COPY(gpr[11]);	COPY(gpr[12]);	COPY(gpr[13]);	COPY(gpr[14]);	COPY(gpr[15]);	COPY(gpr[16]);	COPY(gpr[17]);	COPY(gpr[18]);	COPY(gpr[19]);	COPY(gpr[20]);	COPY(gpr[21]);	COPY(gpr[22]);	COPY(gpr[23]);	COPY(gpr[24]);	COPY(gpr[25]);	COPY(gpr[26]);	COPY(gpr[27]);	COPY(gpr[28]);	COPY(gpr[29]);	COPY(gpr[30]);	COPY(gpr[31]);	COPY(pc);	COPY(psw);	COPY(ctpc);	COPY(ctpsw);	COPY(ctbp);#undef COPY	err |= __put_user(mask, &sc->oldmask);	return err;}/* * Determine which stack to use.. */static inline void *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size){	/* Default to using normal stack */	unsigned long sp = regs->gpr[GPR_SP];	if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! on_sig_stack(sp))		sp = current->sas_ss_sp + current->sas_ss_size;	return (void *)((sp - 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 signal;	frame = get_sigframe(ka, regs, 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->gpr[GPR_LP] = (unsigned long) ka->sa.sa_restorer;	} else {		/* Note, these encodings are _little endian_!  */		/* addi  __NR_sigreturn, r0, r12  */		err |= __put_user(0x6600 | (__NR_sigreturn << 16),				  frame->tramp + 0);		/* trap 0 */		err |= __put_user(0x010007e0,				  frame->tramp + 1);		regs->gpr[GPR_LP] = (unsigned long)frame->tramp;		flush_cache_sigtramp (regs->gpr[GPR_LP]);	}	if (err)		goto give_sigsegv;	/* Set up registers for signal handler.  */	regs->pc = (v850_reg_t) ka->sa.sa_handler;	regs->gpr[GPR_SP] = (v850_reg_t)frame;	/* Signal handler args:  */	regs->gpr[GPR_ARG0] = signal; /* arg 0: signum */	regs->gpr[GPR_ARG1] = (v850_reg_t)&frame->sc;/* arg 1: sigcontext */	set_fs(USER_DS);#if DEBUG_SIG	printk("SIG deliver (%s:%d): sp=%p pc=%08lx ra=%08lx\n",		current->comm, current->pid, frame, regs->pc, );#endif	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 signal;	frame = get_sigframe(ka, regs, 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->gpr[GPR_SP]),			  &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->gpr[GPR_LP] = (unsigned long) ka->sa.sa_restorer;	} else {		/* Note, these encodings are _little endian_!  */		/* addi  __NR_sigreturn, r0, r12  */		err |= __put_user(0x6600 | (__NR_sigreturn << 16),				  frame->tramp + 0);		/* trap 0 */		err |= __put_user(0x010007e0,				  frame->tramp + 1);		regs->gpr[GPR_LP] = (unsigned long)frame->tramp;		flush_cache_sigtramp (regs->gpr[GPR_LP]);	}	if (err)		goto give_sigsegv;	/* Set up registers for signal handler.  */	regs->pc = (v850_reg_t) ka->sa.sa_handler;	regs->gpr[GPR_SP] = (v850_reg_t)frame;	/* Signal handler args:  */	regs->gpr[GPR_ARG0] = signal; /* arg 0: signum */	regs->gpr[GPR_ARG1] = (v850_reg_t)&frame->info; /* arg 1: siginfo */	regs->gpr[GPR_ARG2] = (v850_reg_t)&frame->uc; /* arg 2: ucontext */	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	return;give_sigsegv:	force_sigsegv(sig, current);}/* * OK, we're invoking a handler */	static voidhandle_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 (PT_REGS_SYSCALL (regs)) {		/* If so, check system call restarting.. */		switch (regs->gpr[GPR_RVAL]) {		case -ERESTART_RESTARTBLOCK:			current_thread_info()->restart_block.fn =				do_no_restart_syscall;			/* fall through */		case -ERESTARTNOHAND:			regs->gpr[GPR_RVAL] = -EINTR;			break;		case -ERESTARTSYS:			if (!(ka->sa.sa_flags & SA_RESTART)) {				regs->gpr[GPR_RVAL] = -EINTR;				break;			}			/* fallthrough */		case -ERESTARTNOINTR:			regs->gpr[12] = PT_REGS_SYSCALL (regs);			regs->pc -= 4; /* Size of `trap 0' insn.  */		}		PT_REGS_SET_SYSCALL (regs, 0);	}	/* 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);	spin_lock_irq(&current->sighand->siglock);	sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);	if (!(ka->sa.sa_flags & SA_NODEFER))		sigaddset(&current->blocked,sig);	recalc_sigpending();	spin_unlock_irq(&current->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 (!oldset)		oldset = &current->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;	}	/* Did we come from a system call? */	if (PT_REGS_SYSCALL (regs)) {		int rval = (int)regs->gpr[GPR_RVAL];		/* Restart the system call - no handlers present */		if (rval == -ERESTARTNOHAND		    || rval == -ERESTARTSYS		    || rval == -ERESTARTNOINTR)		{			regs->gpr[12] = PT_REGS_SYSCALL (regs);			regs->pc -= 4; /* Size of `trap 0' insn.  */		}		else if (rval == -ERESTART_RESTARTBLOCK) {			regs->gpr[12] = __NR_restart_syscall;			regs->pc -= 4; /* Size of `trap 0' insn.  */		}	}	return 0;}