[GitHub/mt8127/android_kernel_alcatel_ttab.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/io.h>
#include <linux/tracehook.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>

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

/*
 * 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 (!(boot_cpu_data.flags & CPU_HAS_FPU))
		return 0;

	set_used_math();
	return __copy_from_user(&tsk->thread.xstate->hardfpu, &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 (!(boot_cpu_data.flags & CPU_HAS_FPU))
		return 0;

	if (!used_math())
		return __put_user(0, &sc->sc_ownedfp);

	if (__put_user(1, &sc->sc_ownedfp))
		return -EFAULT;

	/* 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.xstate->hardfpu,
			      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 (boot_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();
		err |= __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;

	set_current_blocked(&set);

	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;

	set_current_blocked(&set);

	if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &r0))
		goto badframe;

	if (restore_altstack(&frame->uc.uc_stack))
		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;

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

	if (err)
		goto give_sigsegv;

	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 |= __save_altstack(&frame->uc.uc_stack, regs->regs[15]);
	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;
		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] = (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;

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

	if (err)
		goto give_sigsegv;

	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 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(__raw_readw(regs->pc - 4));
			break;
	}
}

/*
 * OK, we're invoking a handler
 */
static void
handle_signal(unsigned long sig, struct k_sigaction *ka, siginfo_t *info,
	      struct pt_regs *regs, unsigned int save_r0)
{
	sigset_t *oldset = sigmask_to_save();
	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 (ret)
		return;
	signal_delivered(sig, info, ka, regs,
			test_thread_flag(TIF_SINGLESTEP));
}

/*
 * 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;

	/*
	 * 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;

	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.  */
		handle_signal(signr, &ka, &info, regs, save_r0);
		return;
	}

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

	/*
	 * If there's no signal to deliver, we just put the saved sigmask
	 * back.
	 */
	restore_saved_sigmask();
}

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);
	}
}
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>
b66d51cb	25	#include <linux/io.h>
ab99c733	26	#include <linux/tracehook.h>
1da177e4 LT	27	#include <asm/ucontext.h>
	28	#include <asm/uaccess.h>
	29	#include <asm/pgtable.h>
	30	#include <asm/cacheflush.h>
fa43972f	31	#include <asm/syscalls.h>
9bbafce2	32	#include <asm/fpu.h>
1da177e4	33
3bc24a1a PM	34	struct fdpic_func_descriptor {
	35	unsigned long text;
	36	unsigned long GOT;
	37	};
	38
2fc742f8 CS	39	/*
	40	* The following define adds a 64 byte gap between the signal
	41	* stack frame and previous contents of the stack. This allows
	42	* frame unwinding in a function epilogue but only if a frame
	43	* pointer is used in the function. This is necessary because
	44	* current gcc compilers (<4.3) do not generate unwind info on
	45	* SH for function epilogues.
	46	*/
	47	#define UNWINDGUARD 64
	48
1da177e4 LT	49	/*
	50	* Do a signal return; undo the signal stack.
	51	*/
	52
	53	#define MOVW(n) (0x9300\|((n)-2)) /* Move mem word at PC+n to R3 */
11cbb70e	54	#if defined(CONFIG_CPU_SH2)
9d4436a6 YS	55	#define TRAP_NOARG 0xc320 /* Syscall w/no args (NR in R3) */
	56	#else
	57	#define TRAP_NOARG 0xc310 /* Syscall w/no args (NR in R3) */
	58	#endif
1da177e4 LT	59	#define OR_R0_R0 0x200b /* or r0,r0 (insert to avoid hardware bug) */
	60
	61	struct sigframe
	62	{
	63	struct sigcontext sc;
	64	unsigned long extramask[_NSIG_WORDS-1];
	65	u16 retcode[8];
	66	};
	67
	68	struct rt_sigframe
	69	{
	70	struct siginfo info;
	71	struct ucontext uc;
	72	u16 retcode[8];
	73	};
	74
	75	#ifdef CONFIG_SH_FPU
	76	static inline int restore_sigcontext_fpu(struct sigcontext __user *sc)
	77	{
	78	struct task_struct *tsk = current;
	79
eaa47704	80	if (!(boot_cpu_data.flags & CPU_HAS_FPU))
1da177e4 LT	81	return 0;
	82
	83	set_used_math();
0ea820cf	84	return __copy_from_user(&tsk->thread.xstate->hardfpu, &sc->sc_fpregs[0],
1da177e4 LT	85	sizeof(long)(162+2));
	86	}
	87
	88	static inline int save_sigcontext_fpu(struct sigcontext __user *sc,
	89	struct pt_regs *regs)
	90	{
	91	struct task_struct *tsk = current;
	92
eaa47704	93	if (!(boot_cpu_data.flags & CPU_HAS_FPU))
1da177e4 LT	94	return 0;
1da177e4 LT	95
a46808e1 AV	96	if (!used_math())
a46808e1 AV	97	return __put_user(0, &sc->sc_ownedfp);
1da177e4	98
a46808e1 AV	99	if (__put_user(1, &sc->sc_ownedfp))
a46808e1 AV	100	return -EFAULT;
1da177e4 LT	101
	102	/* This will cause a "finit" to be triggered by the next
	103	attempted FPU operation by the 'current' process.
	104	*/
	105	clear_used_math();
	106
	107	unlazy_fpu(tsk, regs);
0ea820cf	108	return __copy_to_user(&sc->sc_fpregs[0], &tsk->thread.xstate->hardfpu,
1da177e4 LT	109	sizeof(long)(162+2));
	110	}
	111	#endif /* CONFIG_SH_FPU */
	112
	113	static int
	114	restore_sigcontext(struct pt_regs regs, struct sigcontext __user sc, int *r0_p)
	115	{
	116	unsigned int err = 0;
	117
	118	#define COPY(x) err \|= __get_user(regs->x, &sc->sc_##x)
	119	COPY(regs[1]);
	120	COPY(regs[2]); COPY(regs[3]);
	121	COPY(regs[4]); COPY(regs[5]);
	122	COPY(regs[6]); COPY(regs[7]);
	123	COPY(regs[8]); COPY(regs[9]);
	124	COPY(regs[10]); COPY(regs[11]);
	125	COPY(regs[12]); COPY(regs[13]);
	126	COPY(regs[14]); COPY(regs[15]);
	127	COPY(gbr); COPY(mach);
	128	COPY(macl); COPY(pr);
	129	COPY(sr); COPY(pc);
	130	#undef COPY
	131
	132	#ifdef CONFIG_SH_FPU
eaa47704	133	if (boot_cpu_data.flags & CPU_HAS_FPU) {
1da177e4 LT	134	int owned_fp;
	135	struct task_struct *tsk = current;
	136
	137	regs->sr \|= SR_FD; /* Release FPU */
	138	clear_fpu(tsk, regs);
	139	clear_used_math();
a46808e1	140	err \|= __get_user (owned_fp, &sc->sc_ownedfp);
1da177e4 LT	141	if (owned_fp)
	142	err \|= restore_sigcontext_fpu(sc);
	143	}
	144	#endif
	145
	146	regs->tra = -1; /* disable syscall checks */
	147	err \|= __get_user(*r0_p, &sc->sc_regs[0]);
	148	return err;
	149	}
	150
	151	asmlinkage int sys_sigreturn(unsigned long r4, unsigned long r5,
	152	unsigned long r6, unsigned long r7,
f0bc814c	153	struct pt_regs __regs)
1da177e4	154	{
f0bc814c SM	155	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
f0bc814c SM	156	struct sigframe __user frame = (struct sigframe __user )regs->regs[15];
1da177e4 LT	157	sigset_t set;
	158	int r0;
	159
1bec157a PM	160	/* Always make any pending restarted system calls return -EINTR */
	161	current_thread_info()->restart_block.fn = do_no_restart_syscall;
	162
1da177e4 LT	163	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	164	goto badframe;
	165
	166	if (__get_user(set.sig[0], &frame->sc.oldmask)
	167	\|\| (_NSIG_WORDS > 1
	168	&& __copy_from_user(&set.sig[1], &frame->extramask,
	169	sizeof(frame->extramask))))
	170	goto badframe;
	171
5e047fa1	172	set_current_blocked(&set);
1da177e4	173
f0bc814c	174	if (restore_sigcontext(regs, &frame->sc, &r0))
1da177e4 LT	175	goto badframe;
	176	return r0;
	177
	178	badframe:
	179	force_sig(SIGSEGV, current);
	180	return 0;
	181	}
	182
	183	asmlinkage int sys_rt_sigreturn(unsigned long r4, unsigned long r5,
	184	unsigned long r6, unsigned long r7,
f0bc814c	185	struct pt_regs __regs)
1da177e4	186	{
f0bc814c SM	187	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
f0bc814c SM	188	struct rt_sigframe __user frame = (struct rt_sigframe __user )regs->regs[15];
1da177e4	189	sigset_t set;
1da177e4 LT	190	int r0;
1da177e4 LT	191
1bec157a PM	192	/* Always make any pending restarted system calls return -EINTR */
	193	current_thread_info()->restart_block.fn = do_no_restart_syscall;
	194
1da177e4 LT	195	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
	196	goto badframe;
	197
	198	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
	199	goto badframe;
	200
5e047fa1	201	set_current_blocked(&set);
1da177e4	202
f0bc814c	203	if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &r0))
1da177e4 LT	204	goto badframe;
1da177e4 LT	205
7a879a94	206	if (restore_altstack(&frame->uc.uc_stack))
1da177e4	207	goto badframe;
1da177e4 LT	208
	209	return r0;
	210
	211	badframe:
	212	force_sig(SIGSEGV, current);
	213	return 0;
3aeb884b	214	}
1da177e4 LT	215
	216	/*
	217	* Set up a signal frame.
	218	*/
	219
	220	static int
	221	setup_sigcontext(struct sigcontext __user sc, struct pt_regs regs,
	222	unsigned long mask)
	223	{
	224	int err = 0;
	225
	226	#define COPY(x) err \|= __put_user(regs->x, &sc->sc_##x)
	227	COPY(regs[0]); COPY(regs[1]);
	228	COPY(regs[2]); COPY(regs[3]);
	229	COPY(regs[4]); COPY(regs[5]);
	230	COPY(regs[6]); COPY(regs[7]);
	231	COPY(regs[8]); COPY(regs[9]);
	232	COPY(regs[10]); COPY(regs[11]);
	233	COPY(regs[12]); COPY(regs[13]);
	234	COPY(regs[14]); COPY(regs[15]);
	235	COPY(gbr); COPY(mach);
	236	COPY(macl); COPY(pr);
	237	COPY(sr); COPY(pc);
	238	#undef COPY
	239
	240	#ifdef CONFIG_SH_FPU
	241	err \|= save_sigcontext_fpu(sc, regs);
	242	#endif
	243
	244	/* non-iBCS2 extensions.. */
	245	err \|= __put_user(mask, &sc->oldmask);
	246
	247	return err;
	248	}
	249
	250	/*
	251	* Determine which stack to use..
	252	*/
	253	static inline void __user *
	254	get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
	255	{
	256	if (ka->sa.sa_flags & SA_ONSTACK) {
	257	if (sas_ss_flags(sp) == 0)
	258	sp = current->sas_ss_sp + current->sas_ss_size;
	259	}
	260
2fc742f8	261	return (void __user *)((sp - (frame_size+UNWINDGUARD)) & -8ul);
1da177e4 LT	262	}
1da177e4 LT	263
19f9a34f PM	264	/* These symbols are defined with the addresses in the vsyscall page.
19f9a34f PM	265	See vsyscall-trapa.S. */
94455711 MF	266	extern void __kernel_sigreturn(void);
94455711 MF	267	extern void __kernel_rt_sigreturn(void);
19f9a34f	268
9f23e7e9	269	static int setup_frame(int sig, struct k_sigaction *ka,
1da177e4 LT	270	sigset_t set, struct pt_regs regs)
	271	{
	272	struct sigframe __user *frame;
	273	int err = 0;
	274	int signal;
	275
	276	frame = get_sigframe(ka, regs->regs[15], sizeof(*frame));
	277
	278	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
	279	goto give_sigsegv;
	280
	281	signal = current_thread_info()->exec_domain
	282	&& current_thread_info()->exec_domain->signal_invmap
	283	&& sig < 32
	284	? current_thread_info()->exec_domain->signal_invmap[sig]
	285	: sig;
	286
	287	err \|= setup_sigcontext(&frame->sc, regs, set->sig[0]);
	288
9f23e7e9	289	if (_NSIG_WORDS > 1)
1da177e4 LT	290	err \|= __copy_to_user(frame->extramask, &set->sig[1],
1da177e4 LT	291	sizeof(frame->extramask));
1da177e4 LT	292
	293	/* Set up to return from userspace. If provided, use a stub
	294	already in userspace. */
	295	if (ka->sa.sa_flags & SA_RESTORER) {
	296	regs->pr = (unsigned long) ka->sa.sa_restorer;
19f9a34f PM	297	#ifdef CONFIG_VSYSCALL
	298	} else if (likely(current->mm->context.vdso)) {
	299	regs->pr = VDSO_SYM(&__kernel_sigreturn);
	300	#endif
1da177e4 LT	301	} else {
	302	/* Generate return code (system call to sigreturn) */
	303	err \|= __put_user(MOVW(7), &frame->retcode[0]);
9d4436a6	304	err \|= __put_user(TRAP_NOARG, &frame->retcode[1]);
1da177e4 LT	305	err \|= __put_user(OR_R0_R0, &frame->retcode[2]);
	306	err \|= __put_user(OR_R0_R0, &frame->retcode[3]);
	307	err \|= __put_user(OR_R0_R0, &frame->retcode[4]);
	308	err \|= __put_user(OR_R0_R0, &frame->retcode[5]);
	309	err \|= __put_user(OR_R0_R0, &frame->retcode[6]);
	310	err \|= __put_user((__NR_sigreturn), &frame->retcode[7]);
	311	regs->pr = (unsigned long) frame->retcode;
f2fb4e4f	312	flush_icache_range(regs->pr, regs->pr + sizeof(frame->retcode));
1da177e4 LT	313	}
	314
	315	if (err)
	316	goto give_sigsegv;
	317
	318	/* Set up registers for signal handler */
	319	regs->regs[15] = (unsigned long) frame;
	320	regs->regs[4] = signal; /* Arg for signal handler */
	321	regs->regs[5] = 0;
	322	regs->regs[6] = (unsigned long) &frame->sc;
3bc24a1a PM	323
	324	if (current->personality & FDPIC_FUNCPTRS) {
	325	struct fdpic_func_descriptor __user *funcptr =
	326	(struct fdpic_func_descriptor __user *)ka->sa.sa_handler;
	327
a46808e1 AV	328	err \|= __get_user(regs->pc, &funcptr->text);
a46808e1 AV	329	err \|= __get_user(regs->regs[12], &funcptr->GOT);
3bc24a1a PM	330	} else
3bc24a1a PM	331	regs->pc = (unsigned long)ka->sa.sa_handler;
1da177e4	332
a46808e1 AV	333	if (err)
	334	goto give_sigsegv;
	335
1da177e4 LT	336	set_fs(USER_DS);
1da177e4 LT	337
9f23e7e9	338	pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n",
19c5870c	339	current->comm, task_pid_nr(current), frame, regs->pc, regs->pr);
1da177e4	340
9f23e7e9	341	return 0;
1da177e4 LT	342
	343	give_sigsegv:
	344	force_sigsegv(sig, current);
9f23e7e9	345	return -EFAULT;
1da177e4 LT	346	}
1da177e4 LT	347
9f23e7e9	348	static int setup_rt_frame(int sig, struct k_sigaction ka, siginfo_t info,
1da177e4 LT	349	sigset_t set, struct pt_regs regs)
	350	{
	351	struct rt_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 \|= copy_siginfo_to_user(&frame->info, info);
	367
	368	/* Create the ucontext. */
	369	err \|= __put_user(0, &frame->uc.uc_flags);
fa43972f	370	err \|= __put_user(NULL, &frame->uc.uc_link);
7a879a94	371	err \|= __save_altstack(&frame->uc.uc_stack, regs->regs[15]);
1da177e4 LT	372	err \|= setup_sigcontext(&frame->uc.uc_mcontext,
	373	regs, set->sig[0]);
	374	err \|= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
	375
	376	/* Set up to return from userspace. If provided, use a stub
	377	already in userspace. */
	378	if (ka->sa.sa_flags & SA_RESTORER) {
	379	regs->pr = (unsigned long) ka->sa.sa_restorer;
19f9a34f PM	380	#ifdef CONFIG_VSYSCALL
	381	} else if (likely(current->mm->context.vdso)) {
	382	regs->pr = VDSO_SYM(&__kernel_rt_sigreturn);
	383	#endif
1da177e4 LT	384	} else {
	385	/* Generate return code (system call to rt_sigreturn) */
	386	err \|= __put_user(MOVW(7), &frame->retcode[0]);
9d4436a6	387	err \|= __put_user(TRAP_NOARG, &frame->retcode[1]);
1da177e4 LT	388	err \|= __put_user(OR_R0_R0, &frame->retcode[2]);
	389	err \|= __put_user(OR_R0_R0, &frame->retcode[3]);
	390	err \|= __put_user(OR_R0_R0, &frame->retcode[4]);
	391	err \|= __put_user(OR_R0_R0, &frame->retcode[5]);
	392	err \|= __put_user(OR_R0_R0, &frame->retcode[6]);
	393	err \|= __put_user((__NR_rt_sigreturn), &frame->retcode[7]);
	394	regs->pr = (unsigned long) frame->retcode;
4d2947f7	395	flush_icache_range(regs->pr, regs->pr + sizeof(frame->retcode));
1da177e4 LT	396	}
	397
	398	if (err)
	399	goto give_sigsegv;
	400
	401	/* Set up registers for signal handler */
	402	regs->regs[15] = (unsigned long) frame;
	403	regs->regs[4] = signal; /* Arg for signal handler */
	404	regs->regs[5] = (unsigned long) &frame->info;
	405	regs->regs[6] = (unsigned long) &frame->uc;
3bc24a1a PM	406
	407	if (current->personality & FDPIC_FUNCPTRS) {
	408	struct fdpic_func_descriptor __user *funcptr =
	409	(struct fdpic_func_descriptor __user *)ka->sa.sa_handler;
	410
a46808e1 AV	411	err \|= __get_user(regs->pc, &funcptr->text);
a46808e1 AV	412	err \|= __get_user(regs->regs[12], &funcptr->GOT);
3bc24a1a PM	413	} else
3bc24a1a PM	414	regs->pc = (unsigned long)ka->sa.sa_handler;
1da177e4	415
a46808e1 AV	416	if (err)
	417	goto give_sigsegv;
	418
1da177e4 LT	419	set_fs(USER_DS);
1da177e4 LT	420
9f23e7e9	421	pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n",
19c5870c	422	current->comm, task_pid_nr(current), frame, regs->pc, regs->pr);
1da177e4	423
9f23e7e9	424	return 0;
1da177e4 LT	425
	426	give_sigsegv:
	427	force_sigsegv(sig, current);
9f23e7e9	428	return -EFAULT;
1da177e4 LT	429	}
1da177e4 LT	430
f8b890ab PM	431	static inline void
	432	handle_syscall_restart(unsigned long save_r0, struct pt_regs *regs,
	433	struct sigaction *sa)
	434	{
	435	/* If we're not from a syscall, bail out */
	436	if (regs->tra < 0)
	437	return;
	438
	439	/* check for system call restart.. */
	440	switch (regs->regs[0]) {
	441	case -ERESTART_RESTARTBLOCK:
	442	case -ERESTARTNOHAND:
	443	no_system_call_restart:
	444	regs->regs[0] = -EINTR;
f8b890ab PM	445	break;
	446
	447	case -ERESTARTSYS:
	448	if (!(sa->sa_flags & SA_RESTART))
	449	goto no_system_call_restart;
	450	/* fallthrough */
	451	case -ERESTARTNOINTR:
	452	regs->regs[0] = save_r0;
9d56dd3b	453	regs->pc -= instruction_size(__raw_readw(regs->pc - 4));
f8b890ab PM	454	break;
	455	}
	456	}
	457
1da177e4 LT	458	/*
	459	* OK, we're invoking a handler
	460	*/
a610d6e6	461	static void
1da177e4	462	handle_signal(unsigned long sig, struct k_sigaction ka, siginfo_t info,
b7f9a11a	463	struct pt_regs *regs, unsigned int save_r0)
1da177e4	464	{
b7f9a11a	465	sigset_t *oldset = sigmask_to_save();
9f23e7e9 PM	466	int ret;
9f23e7e9 PM	467
1da177e4 LT	468	/* Set up the stack frame */
1da177e4 LT	469	if (ka->sa.sa_flags & SA_SIGINFO)
9f23e7e9	470	ret = setup_rt_frame(sig, ka, info, oldset, regs);
1da177e4	471	else
9f23e7e9	472	ret = setup_frame(sig, ka, oldset, regs);
1da177e4	473
a610d6e6 AV	474	if (ret)
a610d6e6 AV	475	return;
efee984c	476	signal_delivered(sig, info, ka, regs,
a610d6e6	477	test_thread_flag(TIF_SINGLESTEP));
1da177e4 LT	478	}
	479
	480	/*
	481	* Note that 'init' is a special process: it doesn't get signals it doesn't
	482	* want to handle. Thus you cannot kill init even with a SIGKILL even by
	483	* mistake.
	484	*
	485	* Note that we go through the signals twice: once to check the signals that
	486	* the kernel can handle, and then we build all the user-level signal handling
	487	* stack-frames in one go after that.
	488	*/
9f23e7e9	489	static void do_signal(struct pt_regs *regs, unsigned int save_r0)
1da177e4 LT	490	{
	491	siginfo_t info;
	492	int signr;
	493	struct k_sigaction ka;
	494
	495	/*
	496	* We want the common case to go fast, which
	497	* is why we may in certain cases get here from
	498	* kernel mode. Just return without doing anything
	499	* if so.
	500	*/
	501	if (!user_mode(regs))
9f23e7e9	502	return;
1da177e4	503
1da177e4 LT	504	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
1da177e4 LT	505	if (signr > 0) {
03f07876	506	handle_syscall_restart(save_r0, regs, &ka.sa);
f8b890ab	507
1da177e4	508	/* Whee! Actually deliver the signal. */
a610d6e6	509	handle_signal(signr, &ka, &info, regs, save_r0);
c8bfa1fd	510	return;
1da177e4 LT	511	}
1da177e4 LT	512
1da177e4 LT	513	/* Did we come from a system call? */
	514	if (regs->tra >= 0) {
	515	/* Restart the system call - no handlers present */
	516	if (regs->regs[0] == -ERESTARTNOHAND \|\|
	517	regs->regs[0] == -ERESTARTSYS \|\|
0b892935	518	regs->regs[0] == -ERESTARTNOINTR) {
c8bfa1fd	519	regs->regs[0] = save_r0;
9d56dd3b	520	regs->pc -= instruction_size(__raw_readw(regs->pc - 4));
0b892935	521	} else if (regs->regs[0] == -ERESTART_RESTARTBLOCK) {
9d56dd3b	522	regs->pc -= instruction_size(__raw_readw(regs->pc - 4));
0b892935	523	regs->regs[3] = __NR_restart_syscall;
1da177e4 LT	524	}
1da177e4 LT	525	}
9f23e7e9	526
56bfc42f PM	527	/*
	528	* If there's no signal to deliver, we just put the saved sigmask
	529	* back.
	530	*/
51a7b448	531	restore_saved_sigmask();
9f23e7e9 PM	532	}
	533
	534	asmlinkage void do_notify_resume(struct pt_regs *regs, unsigned int save_r0,
ab99c733	535	unsigned long thread_info_flags)
9f23e7e9 PM	536	{
9f23e7e9 PM	537	/* deal with pending signal delivery */
ab99c733	538	if (thread_info_flags & _TIF_SIGPENDING)
9f23e7e9	539	do_signal(regs, save_r0);
ab99c733 PM	540
	541	if (thread_info_flags & _TIF_NOTIFY_RESUME) {
	542	clear_thread_flag(TIF_NOTIFY_RESUME);
	543	tracehook_notify_resume(regs);
	544	}
1da177e4	545	}