[linux-block.git] / arch / sh / kernel / signal_32.c

/*
 *  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/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/elf.h>
#include <linux/personality.h>
#include <linux/binfmts.h>
#include <linux/freezer.h>
#include <linux/io.h>
#include <linux/tracehook.h>
#include <asm/system.h>
#include <asm/ucontext.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/cacheflush.h>
#include <asm/syscalls.h>
#include <asm/fpu.h>

#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))

struct fdpic_func_descriptor {
	unsigned long	text;
	unsigned long	GOT;
};

/*
 * The following define adds a 64 byte gap between the signal
 * stack frame and previous contents of the stack.  This allows
 * frame unwinding in a function epilogue but only if a frame
 * pointer is used in the function.  This is necessary because
 * current gcc compilers (<4.3) do not generate unwind info on
 * SH for function epilogues.
 */
#define UNWINDGUARD 64

/*
 * 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)
{
	mask &= _BLOCKABLE;
	spin_lock_irq(&current->sighand->siglock);
	current->saved_sigmask = current->blocked;
	siginitset(&current->blocked, mask);
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);

	current->state = TASK_INTERRUPTIBLE;
	schedule();
	set_thread_flag(TIF_RESTORE_SIGMASK);
	return -ERESTARTNOHAND;
}

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)
{
	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);

	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 */
#if defined(CONFIG_CPU_SH2)
#define TRAP_NOARG 0xc320		/* Syscall w/no args (NR in R3) */
#else
#define TRAP_NOARG 0xc310		/* Syscall w/no args (NR in R3) */
#endif
#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 (!(current_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 (!(current_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 (current_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 pt_regs *regs = RELOC_HIDE(&__regs, 0);
	struct sigframe __user *frame = (struct sigframe __user *)regs->regs[15];
	sigset_t set;
	int r0;

        /* Always make any pending restarted system calls return -EINTR */
	current_thread_info()->restart_block.fn = do_no_restart_syscall;

	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, &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 pt_regs *regs = RELOC_HIDE(&__regs, 0);
	struct rt_sigframe __user *frame = (struct rt_sigframe __user *)regs->regs[15];
	sigset_t set;
	int r0;

	/* Always make any pending restarted system calls return -EINTR */
	current_thread_info()->restart_block.fn = do_no_restart_syscall;

	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, &r0))
		goto badframe;

	if (do_sigaltstack(&frame->uc.uc_stack, NULL,
			   regs->regs[15]) == -EFAULT)
		goto badframe;

	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+UNWINDGUARD)) & -8ul);
}

/* These symbols are defined with the addresses in the vsyscall page.
   See vsyscall-trapa.S.  */
extern void __kernel_sigreturn(void);
extern void __kernel_rt_sigreturn(void);

static int 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;
#ifdef CONFIG_VSYSCALL
	} else if (likely(current->mm->context.vdso)) {
		regs->pr = VDSO_SYM(&__kernel_sigreturn);
#endif
	} else {
		/* Generate return code (system call to sigreturn) */
		err |= __put_user(MOVW(7), &frame->retcode[0]);
		err |= __put_user(TRAP_NOARG, &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;
		flush_icache_range(regs->pr, regs->pr + sizeof(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;

	if (current->personality & FDPIC_FUNCPTRS) {
		struct fdpic_func_descriptor __user *funcptr =
			(struct fdpic_func_descriptor __user *)ka->sa.sa_handler;

		__get_user(regs->pc, &funcptr->text);
		__get_user(regs->regs[12], &funcptr->GOT);
	} else
		regs->pc = (unsigned long)ka->sa.sa_handler;

	set_fs(USER_DS);

	pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n",
		 current->comm, task_pid_nr(current), frame, regs->pc, regs->pr);

	return 0;

give_sigsegv:
	force_sigsegv(sig, current);
	return -EFAULT;
}

static int 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(NULL, &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;
#ifdef CONFIG_VSYSCALL
	} else if (likely(current->mm->context.vdso)) {
		regs->pr = VDSO_SYM(&__kernel_rt_sigreturn);
#endif
	} else {
		/* Generate return code (system call to rt_sigreturn) */
		err |= __put_user(MOVW(7), &frame->retcode[0]);
		err |= __put_user(TRAP_NOARG, &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;

	if (current->personality & FDPIC_FUNCPTRS) {
		struct fdpic_func_descriptor __user *funcptr =
			(struct fdpic_func_descriptor __user *)ka->sa.sa_handler;

		__get_user(regs->pc, &funcptr->text);
		__get_user(regs->regs[12], &funcptr->GOT);
	} else
		regs->pc = (unsigned long)ka->sa.sa_handler;

	set_fs(USER_DS);

	pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n",
		 current->comm, task_pid_nr(current), frame, regs->pc, regs->pr);

	flush_icache_range(regs->pr, regs->pr + sizeof(frame->retcode));

	return 0;

give_sigsegv:
	force_sigsegv(sig, current);
	return -EFAULT;
}

static inline void
handle_syscall_restart(unsigned long save_r0, struct pt_regs *regs,
		       struct sigaction *sa)
{
	/* If we're not from a syscall, bail out */
	if (regs->tra < 0)
		return;

	/* check for system call restart.. */
	switch (regs->regs[0]) {
		case -ERESTART_RESTARTBLOCK:
		case -ERESTARTNOHAND:
		no_system_call_restart:
			regs->regs[0] = -EINTR;
			break;

		case -ERESTARTSYS:
			if (!(sa->sa_flags & SA_RESTART))
				goto no_system_call_restart;
		/* fallthrough */
		case -ERESTARTNOINTR:
			regs->regs[0] = save_r0;
			regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
			break;
	}
}

/*
 * OK, we're invoking a handler
 */
static int
handle_signal(unsigned long sig, struct k_sigaction *ka, siginfo_t *info,
	      sigset_t *oldset, struct pt_regs *regs, unsigned int save_r0)
{
	int ret;

	/* Set up the stack frame */
	if (ka->sa.sa_flags & SA_SIGINFO)
		ret = setup_rt_frame(sig, ka, info, oldset, regs);
	else
		ret = setup_frame(sig, ka, oldset, regs);

	if (ka->sa.sa_flags & SA_ONESHOT)
		ka->sa.sa_handler = SIG_DFL;

	if (ret == 0) {
		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);
	}

	return ret;
}

/*
 * 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.
 */
static void do_signal(struct pt_regs *regs, unsigned int save_r0)
{
	siginfo_t info;
	int signr;
	struct k_sigaction ka;
	sigset_t *oldset;

	/*
	 * 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 (try_to_freeze())
		goto no_signal;

	if (test_thread_flag(TIF_RESTORE_SIGMASK))
		oldset = &current->saved_sigmask;
	else
		oldset = &current->blocked;

	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
	if (signr > 0) {
		handle_syscall_restart(save_r0, regs, &ka.sa);

		/* Whee!  Actually deliver the signal.  */
		if (handle_signal(signr, &ka, &info, oldset,
				  regs, save_r0) == 0) {
			/* a signal was successfully delivered; the saved
			 * sigmask will have been stored in the signal frame,
			 * and will be restored by sigreturn, so we can simply
			 * clear the TIF_RESTORE_SIGMASK flag */
			if (test_thread_flag(TIF_RESTORE_SIGMASK))
				clear_thread_flag(TIF_RESTORE_SIGMASK);

			tracehook_signal_handler(signr, &info, &ka, regs,
					test_thread_flag(TIF_SINGLESTEP));
		}

		return;
	}

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] = save_r0;
			regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
		} else if (regs->regs[0] == -ERESTART_RESTARTBLOCK) {
			regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
			regs->regs[3] = __NR_restart_syscall;
		}
	}

	/* if there's no signal to deliver, we just put the saved sigmask
	 * back */
	if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
		clear_thread_flag(TIF_RESTORE_SIGMASK);
		sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
	}
}

asmlinkage void do_notify_resume(struct pt_regs *regs, unsigned int save_r0,
				 unsigned long thread_info_flags)
{
	/* deal with pending signal delivery */
	if (thread_info_flags & _TIF_SIGPENDING)
		do_signal(regs, save_r0);

	if (thread_info_flags & _TIF_NOTIFY_RESUME) {
		clear_thread_flag(TIF_NOTIFY_RESUME);
		tracehook_notify_resume(regs);
		if (current->replacement_session_keyring)
			key_replace_session_keyring();
	}
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/arch/sh/kernel/signal.c
	3	*
	4	* Copyright (C) 1991, 1992 Linus Torvalds
	5	*
	6	* 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
	7	*
	8	* SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
	9	*
	10	*/
1da177e4 LT	11	#include <linux/sched.h>
	12	#include <linux/mm.h>
	13	#include <linux/smp.h>
1da177e4 LT	14	#include <linux/kernel.h>
	15	#include <linux/signal.h>
	16	#include <linux/errno.h>
	17	#include <linux/wait.h>
	18	#include <linux/ptrace.h>
	19	#include <linux/unistd.h>
	20	#include <linux/stddef.h>
	21	#include <linux/tty.h>
19f9a34f	22	#include <linux/elf.h>
1da177e4 LT	23	#include <linux/personality.h>
1da177e4 LT	24	#include <linux/binfmts.h>
7dfb7103	25	#include <linux/freezer.h>
b66d51cb	26	#include <linux/io.h>
ab99c733	27	#include <linux/tracehook.h>
bd079997	28	#include <asm/system.h>
1da177e4 LT	29	#include <asm/ucontext.h>
	30	#include <asm/uaccess.h>
	31	#include <asm/pgtable.h>
	32	#include <asm/cacheflush.h>
fa43972f	33	#include <asm/syscalls.h>
9bbafce2	34	#include <asm/fpu.h>
1da177e4	35
1da177e4 LT	36	#define _BLOCKABLE (~(sigmask(SIGKILL) \| sigmask(SIGSTOP)))
1da177e4 LT	37
3bc24a1a PM	38	struct fdpic_func_descriptor {
	39	unsigned long text;
	40	unsigned long GOT;
	41	};
	42
2fc742f8 CS	43	/*
	44	* The following define adds a 64 byte gap between the signal
	45	* stack frame and previous contents of the stack. This allows
	46	* frame unwinding in a function epilogue but only if a frame
	47	* pointer is used in the function. This is necessary because
	48	* current gcc compilers (<4.3) do not generate unwind info on
	49	* SH for function epilogues.
	50	*/
	51	#define UNWINDGUARD 64
	52
1da177e4 LT	53	/*
	54	* Atomically swap in the new signal mask, and wait for a signal.
	55	*/
	56	asmlinkage int
	57	sys_sigsuspend(old_sigset_t mask,
	58	unsigned long r5, unsigned long r6, unsigned long r7,
f0bc814c	59	struct pt_regs __regs)
1da177e4	60	{
1da177e4 LT	61	mask &= _BLOCKABLE;
1da177e4 LT	62	spin_lock_irq(&current->sighand->siglock);
9f23e7e9	63	current->saved_sigmask = current->blocked;
1da177e4 LT	64	siginitset(&current->blocked, mask);
	65	recalc_sigpending();
	66	spin_unlock_irq(&current->sighand->siglock);
	67
9f23e7e9 PM	68	current->state = TASK_INTERRUPTIBLE;
	69	schedule();
	70	set_thread_flag(TIF_RESTORE_SIGMASK);
	71	return -ERESTARTNOHAND;
1da177e4 LT	72	}
1da177e4 LT	73
f0bc814c	74	asmlinkage int
1da177e4 LT	75	sys_sigaction(int sig, const struct old_sigaction __user *act,
	76	struct old_sigaction __user *oact)
	77	{
	78	struct k_sigaction new_ka, old_ka;
	79	int ret;
	80
	81	if (act) {
	82	old_sigset_t mask;
	83	if (!access_ok(VERIFY_READ, act, sizeof(*act)) \|\|
	84	__get_user(new_ka.sa.sa_handler, &act->sa_handler) \|\|
	85	__get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
	86	return -EFAULT;
	87	__get_user(new_ka.sa.sa_flags, &act->sa_flags);
	88	__get_user(mask, &act->sa_mask);
	89	siginitset(&new_ka.sa.sa_mask, mask);
	90	}
	91
	92	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
	93
	94	if (!ret && oact) {
	95	if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) \|\|
	96	__put_user(old_ka.sa.sa_handler, &oact->sa_handler) \|\|
	97	__put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
	98	return -EFAULT;
	99	__put_user(old_ka.sa.sa_flags, &oact->sa_flags);
	100	__put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
	101	}
	102
	103	return ret;
	104	}
	105
	106	asmlinkage int
	107	sys_sigaltstack(const stack_t __user uss, stack_t __user uoss,
	108	unsigned long r6, unsigned long r7,
f0bc814c	109	struct pt_regs __regs)
1da177e4	110	{
f0bc814c SM	111	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
	112
	113	return do_sigaltstack(uss, uoss, regs->regs[15]);
1da177e4 LT	114	}
	115
	116
	117	/*
	118	* Do a signal return; undo the signal stack.
	119	*/
	120
	121	#define MOVW(n) (0x9300\|((n)-2)) /* Move mem word at PC+n to R3 */
11cbb70e	122	#if defined(CONFIG_CPU_SH2)
9d4436a6 YS	123	#define TRAP_NOARG 0xc320 /* Syscall w/no args (NR in R3) */
	124	#else
	125	#define TRAP_NOARG 0xc310 /* Syscall w/no args (NR in R3) */
	126	#endif
1da177e4 LT	127	#define OR_R0_R0 0x200b /* or r0,r0 (insert to avoid hardware bug) */
	128
	129	struct sigframe
	130	{
	131	struct sigcontext sc;
	132	unsigned long extramask[_NSIG_WORDS-1];
	133	u16 retcode[8];
	134	};
	135
	136	struct rt_sigframe
	137	{
	138	struct siginfo info;
	139	struct ucontext uc;
	140	u16 retcode[8];
	141	};
	142
	143	#ifdef CONFIG_SH_FPU
	144	static inline int restore_sigcontext_fpu(struct sigcontext __user *sc)
	145	{
	146	struct task_struct *tsk = current;
	147
11c19656	148	if (!(current_cpu_data.flags & CPU_HAS_FPU))
1da177e4 LT	149	return 0;
	150
	151	set_used_math();
	152	return __copy_from_user(&tsk->thread.fpu.hard, &sc->sc_fpregs[0],
	153	sizeof(long)(162+2));
	154	}
	155
	156	static inline int save_sigcontext_fpu(struct sigcontext __user *sc,
	157	struct pt_regs *regs)
	158	{
	159	struct task_struct *tsk = current;
	160
11c19656	161	if (!(current_cpu_data.flags & CPU_HAS_FPU))
1da177e4 LT	162	return 0;
	163
	164	if (!used_math()) {
	165	__put_user(0, &sc->sc_ownedfp);
	166	return 0;
	167	}
	168
	169	__put_user(1, &sc->sc_ownedfp);
	170
	171	/* This will cause a "finit" to be triggered by the next
	172	attempted FPU operation by the 'current' process.
	173	*/
	174	clear_used_math();
	175
	176	unlazy_fpu(tsk, regs);
	177	return __copy_to_user(&sc->sc_fpregs[0], &tsk->thread.fpu.hard,
	178	sizeof(long)(162+2));
	179	}
	180	#endif /* CONFIG_SH_FPU */
	181
	182	static int
	183	restore_sigcontext(struct pt_regs regs, struct sigcontext __user sc, int *r0_p)
	184	{
	185	unsigned int err = 0;
	186
	187	#define COPY(x) err \|= __get_user(regs->x, &sc->sc_##x)
	188	COPY(regs[1]);
	189	COPY(regs[2]); COPY(regs[3]);
	190	COPY(regs[4]); COPY(regs[5]);
	191	COPY(regs[6]); COPY(regs[7]);
	192	COPY(regs[8]); COPY(regs[9]);
	193	COPY(regs[10]); COPY(regs[11]);
	194	COPY(regs[12]); COPY(regs[13]);
	195	COPY(regs[14]); COPY(regs[15]);
	196	COPY(gbr); COPY(mach);
	197	COPY(macl); COPY(pr);
	198	COPY(sr); COPY(pc);
	199	#undef COPY
	200
	201	#ifdef CONFIG_SH_FPU
11c19656	202	if (current_cpu_data.flags & CPU_HAS_FPU) {
1da177e4 LT	203	int owned_fp;
	204	struct task_struct *tsk = current;
	205
	206	regs->sr \|= SR_FD; /* Release FPU */
	207	clear_fpu(tsk, regs);
	208	clear_used_math();
	209	__get_user (owned_fp, &sc->sc_ownedfp);
	210	if (owned_fp)
	211	err \|= restore_sigcontext_fpu(sc);
	212	}
	213	#endif
	214
	215	regs->tra = -1; /* disable syscall checks */
	216	err \|= __get_user(*r0_p, &sc->sc_regs[0]);
	217	return err;
	218	}
	219
	220	asmlinkage int sys_sigreturn(unsigned long r4, unsigned long r5,
	221	unsigned long r6, unsigned long r7,
f0bc814c	222	struct pt_regs __regs)
1da177e4	223	{
f0bc814c SM	224	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
f0bc814c SM	225	struct sigframe __user frame = (struct sigframe __user )regs->regs[15];
1da177e4 LT	226	sigset_t set;
	227	int r0;
	228
1bec157a PM	229	/* Always make any pending restarted system calls return -EINTR */
	230	current_thread_info()->restart_block.fn = do_no_restart_syscall;
	231
1da177e4 LT	232	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	233	goto badframe;
	234
	235	if (__get_user(set.sig[0], &frame->sc.oldmask)
	236	\|\| (_NSIG_WORDS > 1
	237	&& __copy_from_user(&set.sig[1], &frame->extramask,
	238	sizeof(frame->extramask))))
	239	goto badframe;
	240
	241	sigdelsetmask(&set, ~_BLOCKABLE);
	242
	243	spin_lock_irq(&current->sighand->siglock);
	244	current->blocked = set;
	245	recalc_sigpending();
	246	spin_unlock_irq(&current->sighand->siglock);
	247
f0bc814c	248	if (restore_sigcontext(regs, &frame->sc, &r0))
1da177e4 LT	249	goto badframe;
	250	return r0;
	251
	252	badframe:
	253	force_sig(SIGSEGV, current);
	254	return 0;
	255	}
	256
	257	asmlinkage int sys_rt_sigreturn(unsigned long r4, unsigned long r5,
	258	unsigned long r6, unsigned long r7,
f0bc814c	259	struct pt_regs __regs)
1da177e4	260	{
f0bc814c SM	261	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
f0bc814c SM	262	struct rt_sigframe __user frame = (struct rt_sigframe __user )regs->regs[15];
1da177e4	263	sigset_t set;
1da177e4 LT	264	int r0;
1da177e4 LT	265
1bec157a PM	266	/* Always make any pending restarted system calls return -EINTR */
	267	current_thread_info()->restart_block.fn = do_no_restart_syscall;
	268
1da177e4 LT	269	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	270	goto badframe;
	271
	272	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
	273	goto badframe;
	274
	275	sigdelsetmask(&set, ~_BLOCKABLE);
	276	spin_lock_irq(&current->sighand->siglock);
	277	current->blocked = set;
	278	recalc_sigpending();
	279	spin_unlock_irq(&current->sighand->siglock);
	280
f0bc814c	281	if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &r0))
1da177e4 LT	282	goto badframe;
1da177e4 LT	283
fa43972f PM	284	if (do_sigaltstack(&frame->uc.uc_stack, NULL,
fa43972f PM	285	regs->regs[15]) == -EFAULT)
1da177e4	286	goto badframe;
1da177e4 LT	287
	288	return r0;
	289
	290	badframe:
	291	force_sig(SIGSEGV, current);
	292	return 0;
3aeb884b	293	}
1da177e4 LT	294
	295	/*
	296	* Set up a signal frame.
	297	*/
	298
	299	static int
	300	setup_sigcontext(struct sigcontext __user sc, struct pt_regs regs,
	301	unsigned long mask)
	302	{
	303	int err = 0;
	304
	305	#define COPY(x) err \|= __put_user(regs->x, &sc->sc_##x)
	306	COPY(regs[0]); COPY(regs[1]);
	307	COPY(regs[2]); COPY(regs[3]);
	308	COPY(regs[4]); COPY(regs[5]);
	309	COPY(regs[6]); COPY(regs[7]);
	310	COPY(regs[8]); COPY(regs[9]);
	311	COPY(regs[10]); COPY(regs[11]);
	312	COPY(regs[12]); COPY(regs[13]);
	313	COPY(regs[14]); COPY(regs[15]);
	314	COPY(gbr); COPY(mach);
	315	COPY(macl); COPY(pr);
	316	COPY(sr); COPY(pc);
	317	#undef COPY
	318
	319	#ifdef CONFIG_SH_FPU
	320	err \|= save_sigcontext_fpu(sc, regs);
	321	#endif
	322
	323	/* non-iBCS2 extensions.. */
	324	err \|= __put_user(mask, &sc->oldmask);
	325
	326	return err;
	327	}
	328
	329	/*
	330	* Determine which stack to use..
	331	*/
	332	static inline void __user *
	333	get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
	334	{
	335	if (ka->sa.sa_flags & SA_ONSTACK) {
	336	if (sas_ss_flags(sp) == 0)
	337	sp = current->sas_ss_sp + current->sas_ss_size;
	338	}
	339
2fc742f8	340	return (void __user *)((sp - (frame_size+UNWINDGUARD)) & -8ul);
1da177e4 LT	341	}
1da177e4 LT	342
19f9a34f PM	343	/* These symbols are defined with the addresses in the vsyscall page.
19f9a34f PM	344	See vsyscall-trapa.S. */
94455711 MF	345	extern void __kernel_sigreturn(void);
94455711 MF	346	extern void __kernel_rt_sigreturn(void);
19f9a34f	347
9f23e7e9	348	static int setup_frame(int sig, struct k_sigaction *ka,
1da177e4 LT	349	sigset_t set, struct pt_regs regs)
	350	{
	351	struct sigframe __user *frame;
	352	int err = 0;
	353	int signal;
	354
	355	frame = get_sigframe(ka, regs->regs[15], sizeof(*frame));
	356
	357	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
	358	goto give_sigsegv;
	359
	360	signal = current_thread_info()->exec_domain
	361	&& current_thread_info()->exec_domain->signal_invmap
	362	&& sig < 32
	363	? current_thread_info()->exec_domain->signal_invmap[sig]
	364	: sig;
	365
	366	err \|= setup_sigcontext(&frame->sc, regs, set->sig[0]);
	367
9f23e7e9	368	if (_NSIG_WORDS > 1)
1da177e4 LT	369	err \|= __copy_to_user(frame->extramask, &set->sig[1],
1da177e4 LT	370	sizeof(frame->extramask));
1da177e4 LT	371
	372	/* Set up to return from userspace. If provided, use a stub
	373	already in userspace. */
	374	if (ka->sa.sa_flags & SA_RESTORER) {
	375	regs->pr = (unsigned long) ka->sa.sa_restorer;
19f9a34f PM	376	#ifdef CONFIG_VSYSCALL
	377	} else if (likely(current->mm->context.vdso)) {
	378	regs->pr = VDSO_SYM(&__kernel_sigreturn);
	379	#endif
1da177e4 LT	380	} else {
	381	/* Generate return code (system call to sigreturn) */
	382	err \|= __put_user(MOVW(7), &frame->retcode[0]);
9d4436a6	383	err \|= __put_user(TRAP_NOARG, &frame->retcode[1]);
1da177e4 LT	384	err \|= __put_user(OR_R0_R0, &frame->retcode[2]);
	385	err \|= __put_user(OR_R0_R0, &frame->retcode[3]);
	386	err \|= __put_user(OR_R0_R0, &frame->retcode[4]);
	387	err \|= __put_user(OR_R0_R0, &frame->retcode[5]);
	388	err \|= __put_user(OR_R0_R0, &frame->retcode[6]);
	389	err \|= __put_user((__NR_sigreturn), &frame->retcode[7]);
	390	regs->pr = (unsigned long) frame->retcode;
f2fb4e4f	391	flush_icache_range(regs->pr, regs->pr + sizeof(frame->retcode));
1da177e4 LT	392	}
	393
	394	if (err)
	395	goto give_sigsegv;
	396
	397	/* Set up registers for signal handler */
	398	regs->regs[15] = (unsigned long) frame;
	399	regs->regs[4] = signal; /* Arg for signal handler */
	400	regs->regs[5] = 0;
	401	regs->regs[6] = (unsigned long) &frame->sc;
3bc24a1a PM	402
	403	if (current->personality & FDPIC_FUNCPTRS) {
	404	struct fdpic_func_descriptor __user *funcptr =
	405	(struct fdpic_func_descriptor __user *)ka->sa.sa_handler;
	406
	407	__get_user(regs->pc, &funcptr->text);
	408	__get_user(regs->regs[12], &funcptr->GOT);
	409	} else
	410	regs->pc = (unsigned long)ka->sa.sa_handler;
1da177e4 LT	411
	412	set_fs(USER_DS);
	413
9f23e7e9	414	pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n",
19c5870c	415	current->comm, task_pid_nr(current), frame, regs->pc, regs->pr);
1da177e4	416
9f23e7e9	417	return 0;
1da177e4 LT	418
	419	give_sigsegv:
	420	force_sigsegv(sig, current);
9f23e7e9	421	return -EFAULT;
1da177e4 LT	422	}
1da177e4 LT	423
9f23e7e9	424	static int setup_rt_frame(int sig, struct k_sigaction ka, siginfo_t info,
1da177e4 LT	425	sigset_t set, struct pt_regs regs)
	426	{
	427	struct rt_sigframe __user *frame;
	428	int err = 0;
	429	int signal;
	430
	431	frame = get_sigframe(ka, regs->regs[15], sizeof(*frame));
	432
	433	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
	434	goto give_sigsegv;
	435
	436	signal = current_thread_info()->exec_domain
	437	&& current_thread_info()->exec_domain->signal_invmap
	438	&& sig < 32
	439	? current_thread_info()->exec_domain->signal_invmap[sig]
	440	: sig;
	441
	442	err \|= copy_siginfo_to_user(&frame->info, info);
	443
	444	/* Create the ucontext. */
	445	err \|= __put_user(0, &frame->uc.uc_flags);
fa43972f	446	err \|= __put_user(NULL, &frame->uc.uc_link);
1da177e4 LT	447	err \|= __put_user((void *)current->sas_ss_sp,
	448	&frame->uc.uc_stack.ss_sp);
	449	err \|= __put_user(sas_ss_flags(regs->regs[15]),
	450	&frame->uc.uc_stack.ss_flags);
	451	err \|= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
	452	err \|= setup_sigcontext(&frame->uc.uc_mcontext,
	453	regs, set->sig[0]);
	454	err \|= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
	455
	456	/* Set up to return from userspace. If provided, use a stub
	457	already in userspace. */
	458	if (ka->sa.sa_flags & SA_RESTORER) {
	459	regs->pr = (unsigned long) ka->sa.sa_restorer;
19f9a34f PM	460	#ifdef CONFIG_VSYSCALL
	461	} else if (likely(current->mm->context.vdso)) {
	462	regs->pr = VDSO_SYM(&__kernel_rt_sigreturn);
	463	#endif
1da177e4 LT	464	} else {
	465	/* Generate return code (system call to rt_sigreturn) */
	466	err \|= __put_user(MOVW(7), &frame->retcode[0]);
9d4436a6	467	err \|= __put_user(TRAP_NOARG, &frame->retcode[1]);
1da177e4 LT	468	err \|= __put_user(OR_R0_R0, &frame->retcode[2]);
	469	err \|= __put_user(OR_R0_R0, &frame->retcode[3]);
	470	err \|= __put_user(OR_R0_R0, &frame->retcode[4]);
	471	err \|= __put_user(OR_R0_R0, &frame->retcode[5]);
	472	err \|= __put_user(OR_R0_R0, &frame->retcode[6]);
	473	err \|= __put_user((__NR_rt_sigreturn), &frame->retcode[7]);
	474	regs->pr = (unsigned long) frame->retcode;
	475	}
	476
	477	if (err)
	478	goto give_sigsegv;
	479
	480	/* Set up registers for signal handler */
	481	regs->regs[15] = (unsigned long) frame;
	482	regs->regs[4] = signal; /* Arg for signal handler */
	483	regs->regs[5] = (unsigned long) &frame->info;
	484	regs->regs[6] = (unsigned long) &frame->uc;
3bc24a1a PM	485
	486	if (current->personality & FDPIC_FUNCPTRS) {
	487	struct fdpic_func_descriptor __user *funcptr =
	488	(struct fdpic_func_descriptor __user *)ka->sa.sa_handler;
	489
	490	__get_user(regs->pc, &funcptr->text);
	491	__get_user(regs->regs[12], &funcptr->GOT);
	492	} else
	493	regs->pc = (unsigned long)ka->sa.sa_handler;
1da177e4 LT	494
	495	set_fs(USER_DS);
	496
9f23e7e9	497	pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n",
19c5870c	498	current->comm, task_pid_nr(current), frame, regs->pc, regs->pr);
1da177e4	499
09b5a10c	500	flush_icache_range(regs->pr, regs->pr + sizeof(frame->retcode));
9f23e7e9 PM	501
9f23e7e9 PM	502	return 0;
1da177e4 LT	503
	504	give_sigsegv:
	505	force_sigsegv(sig, current);
9f23e7e9	506	return -EFAULT;
1da177e4 LT	507	}
1da177e4 LT	508
f8b890ab PM	509	static inline void
	510	handle_syscall_restart(unsigned long save_r0, struct pt_regs *regs,
	511	struct sigaction *sa)
	512	{
	513	/* If we're not from a syscall, bail out */
	514	if (regs->tra < 0)
	515	return;
	516
	517	/* check for system call restart.. */
	518	switch (regs->regs[0]) {
	519	case -ERESTART_RESTARTBLOCK:
	520	case -ERESTARTNOHAND:
	521	no_system_call_restart:
	522	regs->regs[0] = -EINTR;
f8b890ab PM	523	break;
	524
	525	case -ERESTARTSYS:
	526	if (!(sa->sa_flags & SA_RESTART))
	527	goto no_system_call_restart;
	528	/* fallthrough */
	529	case -ERESTARTNOINTR:
	530	regs->regs[0] = save_r0;
	531	regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
	532	break;
	533	}
	534	}
	535
1da177e4 LT	536	/*
	537	* OK, we're invoking a handler
	538	*/
9f23e7e9	539	static int
1da177e4	540	handle_signal(unsigned long sig, struct k_sigaction ka, siginfo_t info,
69a33147	541	sigset_t oldset, struct pt_regs regs, unsigned int save_r0)
1da177e4	542	{
9f23e7e9 PM	543	int ret;
9f23e7e9 PM	544
1da177e4 LT	545	/* Set up the stack frame */
1da177e4 LT	546	if (ka->sa.sa_flags & SA_SIGINFO)
9f23e7e9	547	ret = setup_rt_frame(sig, ka, info, oldset, regs);
1da177e4	548	else
9f23e7e9	549	ret = setup_frame(sig, ka, oldset, regs);
1da177e4 LT	550
	551	if (ka->sa.sa_flags & SA_ONESHOT)
	552	ka->sa.sa_handler = SIG_DFL;
	553
9f23e7e9 PM	554	if (ret == 0) {
	555	spin_lock_irq(&current->sighand->siglock);
	556	sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
	557	if (!(ka->sa.sa_flags & SA_NODEFER))
	558	sigaddset(&current->blocked,sig);
	559	recalc_sigpending();
	560	spin_unlock_irq(&current->sighand->siglock);
	561	}
	562
	563	return ret;
1da177e4 LT	564	}
	565
	566	/*
	567	* Note that 'init' is a special process: it doesn't get signals it doesn't
	568	* want to handle. Thus you cannot kill init even with a SIGKILL even by
	569	* mistake.
	570	*
	571	* Note that we go through the signals twice: once to check the signals that
	572	* the kernel can handle, and then we build all the user-level signal handling
	573	* stack-frames in one go after that.
	574	*/
9f23e7e9	575	static void do_signal(struct pt_regs *regs, unsigned int save_r0)
1da177e4 LT	576	{
	577	siginfo_t info;
	578	int signr;
	579	struct k_sigaction ka;
9f23e7e9	580	sigset_t *oldset;
1da177e4 LT	581
	582	/*
	583	* We want the common case to go fast, which
	584	* is why we may in certain cases get here from
	585	* kernel mode. Just return without doing anything
	586	* if so.
	587	*/
	588	if (!user_mode(regs))
9f23e7e9	589	return;
1da177e4	590
0e6c1f5f	591	if (try_to_freeze())
1da177e4 LT	592	goto no_signal;
1da177e4 LT	593
9f23e7e9 PM	594	if (test_thread_flag(TIF_RESTORE_SIGMASK))
	595	oldset = &current->saved_sigmask;
	596	else
1da177e4 LT	597	oldset = &current->blocked;
	598
	599	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
	600	if (signr > 0) {
03f07876	601	handle_syscall_restart(save_r0, regs, &ka.sa);
f8b890ab	602
1da177e4	603	/* Whee! Actually deliver the signal. */
3aeb884b PM	604	if (handle_signal(signr, &ka, &info, oldset,
3aeb884b PM	605	regs, save_r0) == 0) {
9f23e7e9 PM	606	/* a signal was successfully delivered; the saved
	607	* sigmask will have been stored in the signal frame,
	608	* and will be restored by sigreturn, so we can simply
	609	* clear the TIF_RESTORE_SIGMASK flag */
	610	if (test_thread_flag(TIF_RESTORE_SIGMASK))
	611	clear_thread_flag(TIF_RESTORE_SIGMASK);
ab99c733 PM	612
	613	tracehook_signal_handler(signr, &info, &ka, regs,
	614	test_thread_flag(TIF_SINGLESTEP));
9f23e7e9	615	}
c8bfa1fd RS	616
c8bfa1fd RS	617	return;
1da177e4 LT	618	}
1da177e4 LT	619
ab99c733	620	no_signal:
1da177e4 LT	621	/* Did we come from a system call? */
	622	if (regs->tra >= 0) {
	623	/* Restart the system call - no handlers present */
	624	if (regs->regs[0] == -ERESTARTNOHAND \|\|
	625	regs->regs[0] == -ERESTARTSYS \|\|
0b892935	626	regs->regs[0] == -ERESTARTNOINTR) {
c8bfa1fd	627	regs->regs[0] = save_r0;
53f983a9	628	regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
0b892935	629	} else if (regs->regs[0] == -ERESTART_RESTARTBLOCK) {
53f983a9	630	regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
0b892935	631	regs->regs[3] = __NR_restart_syscall;
1da177e4 LT	632	}
1da177e4 LT	633	}
9f23e7e9 PM	634
	635	/* if there's no signal to deliver, we just put the saved sigmask
	636	* back */
	637	if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
	638	clear_thread_flag(TIF_RESTORE_SIGMASK);
	639	sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
	640	}
	641	}
	642
	643	asmlinkage void do_notify_resume(struct pt_regs *regs, unsigned int save_r0,
ab99c733	644	unsigned long thread_info_flags)
9f23e7e9 PM	645	{
9f23e7e9 PM	646	/* deal with pending signal delivery */
ab99c733	647	if (thread_info_flags & _TIF_SIGPENDING)
9f23e7e9	648	do_signal(regs, save_r0);
ab99c733 PM	649
	650	if (thread_info_flags & _TIF_NOTIFY_RESUME) {
	651	clear_thread_flag(TIF_NOTIFY_RESUME);
	652	tracehook_notify_resume(regs);
ee18d64c DH	653	if (current->replacement_session_keyring)
ee18d64c DH	654	key_replace_session_keyring();
ab99c733	655	}
1da177e4	656	}