[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / sparc / kernel / signal_64.c

/*
 *  arch/sparc64/kernel/signal.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 *  Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net)
 *  Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
 *  Copyright (C) 1997 Eddie C. Dost   (ecd@skynet.be)
 *  Copyright (C) 1997,1998 Jakub Jelinek   (jj@sunsite.mff.cuni.cz)
 */

#ifdef CONFIG_COMPAT
#include <linux/compat.h>	/* for compat_old_sigset_t */
#endif
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/signal.h>
#include <linux/errno.h>
#include <linux/wait.h>
#include <linux/ptrace.h>
#include <linux/tracehook.h>
#include <linux/unistd.h>
#include <linux/mm.h>
#include <linux/tty.h>
#include <linux/binfmts.h>
#include <linux/bitops.h>

#include <asm/uaccess.h>
#include <asm/ptrace.h>
#include <asm/pgtable.h>
#include <asm/fpumacro.h>
#include <asm/uctx.h>
#include <asm/siginfo.h>
#include <asm/visasm.h>
#include <asm/switch_to.h>
#include <asm/cacheflush.h>

#include "entry.h"
#include "systbls.h"
#include "sigutil.h"

/* {set, get}context() needed for 64-bit SparcLinux userland. */
asmlinkage void sparc64_set_context(struct pt_regs *regs)
{
	struct ucontext __user *ucp = (struct ucontext __user *)
		regs->u_regs[UREG_I0];
	mc_gregset_t __user *grp;
	unsigned long pc, npc, tstate;
	unsigned long fp, i7;
	unsigned char fenab;
	int err;

	flush_user_windows();
	if (get_thread_wsaved()					||
	    (((unsigned long)ucp) & (sizeof(unsigned long)-1))	||
	    (!__access_ok(ucp, sizeof(*ucp))))
		goto do_sigsegv;
	grp  = &ucp->uc_mcontext.mc_gregs;
	err  = __get_user(pc, &((*grp)[MC_PC]));
	err |= __get_user(npc, &((*grp)[MC_NPC]));
	if (err || ((pc | npc) & 3))
		goto do_sigsegv;
	if (regs->u_regs[UREG_I1]) {
		sigset_t set;

		if (_NSIG_WORDS == 1) {
			if (__get_user(set.sig[0], &ucp->uc_sigmask.sig[0]))
				goto do_sigsegv;
		} else {
			if (__copy_from_user(&set, &ucp->uc_sigmask, sizeof(sigset_t)))
				goto do_sigsegv;
		}
		set_current_blocked(&set);
	}
	if (test_thread_flag(TIF_32BIT)) {
		pc &= 0xffffffff;
		npc &= 0xffffffff;
	}
	regs->tpc = pc;
	regs->tnpc = npc;
	err |= __get_user(regs->y, &((*grp)[MC_Y]));
	err |= __get_user(tstate, &((*grp)[MC_TSTATE]));
	regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
	regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));
	err |= __get_user(regs->u_regs[UREG_G1], (&(*grp)[MC_G1]));
	err |= __get_user(regs->u_regs[UREG_G2], (&(*grp)[MC_G2]));
	err |= __get_user(regs->u_regs[UREG_G3], (&(*grp)[MC_G3]));
	err |= __get_user(regs->u_regs[UREG_G4], (&(*grp)[MC_G4]));
	err |= __get_user(regs->u_regs[UREG_G5], (&(*grp)[MC_G5]));
	err |= __get_user(regs->u_regs[UREG_G6], (&(*grp)[MC_G6]));

	/* Skip %g7 as that's the thread register in userspace.  */

	err |= __get_user(regs->u_regs[UREG_I0], (&(*grp)[MC_O0]));
	err |= __get_user(regs->u_regs[UREG_I1], (&(*grp)[MC_O1]));
	err |= __get_user(regs->u_regs[UREG_I2], (&(*grp)[MC_O2]));
	err |= __get_user(regs->u_regs[UREG_I3], (&(*grp)[MC_O3]));
	err |= __get_user(regs->u_regs[UREG_I4], (&(*grp)[MC_O4]));
	err |= __get_user(regs->u_regs[UREG_I5], (&(*grp)[MC_O5]));
	err |= __get_user(regs->u_regs[UREG_I6], (&(*grp)[MC_O6]));
	err |= __get_user(regs->u_regs[UREG_I7], (&(*grp)[MC_O7]));

	err |= __get_user(fp, &(ucp->uc_mcontext.mc_fp));
	err |= __get_user(i7, &(ucp->uc_mcontext.mc_i7));
	err |= __put_user(fp,
	      (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
	err |= __put_user(i7,
	      (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));

	err |= __get_user(fenab, &(ucp->uc_mcontext.mc_fpregs.mcfpu_enab));
	if (fenab) {
		unsigned long *fpregs = current_thread_info()->fpregs;
		unsigned long fprs;
		
		fprs_write(0);
		err |= __get_user(fprs, &(ucp->uc_mcontext.mc_fpregs.mcfpu_fprs));
		if (fprs & FPRS_DL)
			err |= copy_from_user(fpregs,
					      &(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs),
					      (sizeof(unsigned int) * 32));
		if (fprs & FPRS_DU)
			err |= copy_from_user(fpregs+16,
			 ((unsigned long __user *)&(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs))+16,
			 (sizeof(unsigned int) * 32));
		err |= __get_user(current_thread_info()->xfsr[0],
				  &(ucp->uc_mcontext.mc_fpregs.mcfpu_fsr));
		err |= __get_user(current_thread_info()->gsr[0],
				  &(ucp->uc_mcontext.mc_fpregs.mcfpu_gsr));
		regs->tstate &= ~TSTATE_PEF;
	}
	if (err)
		goto do_sigsegv;

	return;
do_sigsegv:
	force_sig(SIGSEGV, current);
}

asmlinkage void sparc64_get_context(struct pt_regs *regs)
{
	struct ucontext __user *ucp = (struct ucontext __user *)
		regs->u_regs[UREG_I0];
	mc_gregset_t __user *grp;
	mcontext_t __user *mcp;
	unsigned long fp, i7;
	unsigned char fenab;
	int err;

	synchronize_user_stack();
	if (get_thread_wsaved() || clear_user(ucp, sizeof(*ucp)))
		goto do_sigsegv;

#if 1
	fenab = 0; /* IMO get_context is like any other system call, thus modifies FPU state -jj */
#else
	fenab = (current_thread_info()->fpsaved[0] & FPRS_FEF);
#endif
		
	mcp = &ucp->uc_mcontext;
	grp = &mcp->mc_gregs;

	/* Skip over the trap instruction, first. */
	if (test_thread_flag(TIF_32BIT)) {
		regs->tpc   = (regs->tnpc & 0xffffffff);
		regs->tnpc  = (regs->tnpc + 4) & 0xffffffff;
	} else {
		regs->tpc   = regs->tnpc;
		regs->tnpc += 4;
	}
	err = 0;
	if (_NSIG_WORDS == 1)
		err |= __put_user(current->blocked.sig[0],
				  (unsigned long __user *)&ucp->uc_sigmask);
	else
		err |= __copy_to_user(&ucp->uc_sigmask, &current->blocked,
				      sizeof(sigset_t));

	err |= __put_user(regs->tstate, &((*grp)[MC_TSTATE]));
	err |= __put_user(regs->tpc, &((*grp)[MC_PC]));
	err |= __put_user(regs->tnpc, &((*grp)[MC_NPC]));
	err |= __put_user(regs->y, &((*grp)[MC_Y]));
	err |= __put_user(regs->u_regs[UREG_G1], &((*grp)[MC_G1]));
	err |= __put_user(regs->u_regs[UREG_G2], &((*grp)[MC_G2]));
	err |= __put_user(regs->u_regs[UREG_G3], &((*grp)[MC_G3]));
	err |= __put_user(regs->u_regs[UREG_G4], &((*grp)[MC_G4]));
	err |= __put_user(regs->u_regs[UREG_G5], &((*grp)[MC_G5]));
	err |= __put_user(regs->u_regs[UREG_G6], &((*grp)[MC_G6]));
	err |= __put_user(regs->u_regs[UREG_G7], &((*grp)[MC_G7]));
	err |= __put_user(regs->u_regs[UREG_I0], &((*grp)[MC_O0]));
	err |= __put_user(regs->u_regs[UREG_I1], &((*grp)[MC_O1]));
	err |= __put_user(regs->u_regs[UREG_I2], &((*grp)[MC_O2]));
	err |= __put_user(regs->u_regs[UREG_I3], &((*grp)[MC_O3]));
	err |= __put_user(regs->u_regs[UREG_I4], &((*grp)[MC_O4]));
	err |= __put_user(regs->u_regs[UREG_I5], &((*grp)[MC_O5]));
	err |= __put_user(regs->u_regs[UREG_I6], &((*grp)[MC_O6]));
	err |= __put_user(regs->u_regs[UREG_I7], &((*grp)[MC_O7]));

	err |= __get_user(fp,
		 (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
	err |= __get_user(i7,
		 (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
	err |= __put_user(fp, &(mcp->mc_fp));
	err |= __put_user(i7, &(mcp->mc_i7));

	err |= __put_user(fenab, &(mcp->mc_fpregs.mcfpu_enab));
	if (fenab) {
		unsigned long *fpregs = current_thread_info()->fpregs;
		unsigned long fprs;
		
		fprs = current_thread_info()->fpsaved[0];
		if (fprs & FPRS_DL)
			err |= copy_to_user(&(mcp->mc_fpregs.mcfpu_fregs), fpregs,
					    (sizeof(unsigned int) * 32));
		if (fprs & FPRS_DU)
			err |= copy_to_user(
                          ((unsigned long __user *)&(mcp->mc_fpregs.mcfpu_fregs))+16, fpregs+16,
			  (sizeof(unsigned int) * 32));
		err |= __put_user(current_thread_info()->xfsr[0], &(mcp->mc_fpregs.mcfpu_fsr));
		err |= __put_user(current_thread_info()->gsr[0], &(mcp->mc_fpregs.mcfpu_gsr));
		err |= __put_user(fprs, &(mcp->mc_fpregs.mcfpu_fprs));
	}
	if (err)
		goto do_sigsegv;

	return;
do_sigsegv:
	force_sig(SIGSEGV, current);
}

struct rt_signal_frame {
	struct sparc_stackf	ss;
	siginfo_t		info;
	struct pt_regs		regs;
	__siginfo_fpu_t __user	*fpu_save;
	stack_t			stack;
	sigset_t		mask;
	__siginfo_rwin_t	*rwin_save;
};

static long _sigpause_common(old_sigset_t set)
{
	sigset_t blocked;
	siginitset(&blocked, set);
	return sigsuspend(&blocked);
}

asmlinkage long sys_sigpause(unsigned int set)
{
	return _sigpause_common(set);
}

asmlinkage long sys_sigsuspend(old_sigset_t set)
{
	return _sigpause_common(set);
}

void do_rt_sigreturn(struct pt_regs *regs)
{
	struct rt_signal_frame __user *sf;
	unsigned long tpc, tnpc, tstate;
	__siginfo_fpu_t __user *fpu_save;
	__siginfo_rwin_t __user *rwin_save;
	sigset_t set;
	int err;

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

	synchronize_user_stack ();
	sf = (struct rt_signal_frame __user *)
		(regs->u_regs [UREG_FP] + STACK_BIAS);

	/* 1. Make sure we are not getting garbage from the user */
	if (((unsigned long) sf) & 3)
		goto segv;

	err = get_user(tpc, &sf->regs.tpc);
	err |= __get_user(tnpc, &sf->regs.tnpc);
	if (test_thread_flag(TIF_32BIT)) {
		tpc &= 0xffffffff;
		tnpc &= 0xffffffff;
	}
	err |= ((tpc | tnpc) & 3);

	/* 2. Restore the state */
	err |= __get_user(regs->y, &sf->regs.y);
	err |= __get_user(tstate, &sf->regs.tstate);
	err |= copy_from_user(regs->u_regs, sf->regs.u_regs, sizeof(regs->u_regs));

	/* User can only change condition codes and %asi in %tstate. */
	regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
	regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));

	err |= __get_user(fpu_save, &sf->fpu_save);
	if (!err && fpu_save)
		err |= restore_fpu_state(regs, fpu_save);

	err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
	err |= do_sigaltstack(&sf->stack, NULL, (unsigned long)sf);

	if (err)
		goto segv;

	err |= __get_user(rwin_save, &sf->rwin_save);
	if (!err && rwin_save) {
		if (restore_rwin_state(rwin_save))
			goto segv;
	}

	regs->tpc = tpc;
	regs->tnpc = tnpc;

	/* Prevent syscall restart.  */
	pt_regs_clear_syscall(regs);

	set_current_blocked(&set);
	return;
segv:
	force_sig(SIGSEGV, current);
}

/* Checks if the fp is valid */
static int invalid_frame_pointer(void __user *fp)
{
	if (((unsigned long) fp) & 15)
		return 1;
	return 0;
}

static inline void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, unsigned long framesize)
{
	unsigned long sp = regs->u_regs[UREG_FP] + STACK_BIAS;

	/*
	 * If we are on the alternate signal stack and would overflow it, don't.
	 * Return an always-bogus address instead so we will die with SIGSEGV.
	 */
	if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize)))
		return (void __user *) -1L;

	/* This is the X/Open sanctioned signal stack switching.  */
	if (ka->sa.sa_flags & SA_ONSTACK) {
		if (sas_ss_flags(sp) == 0)
			sp = current->sas_ss_sp + current->sas_ss_size;
	}

	sp -= framesize;

	/* Always align the stack frame.  This handles two cases.  First,
	 * sigaltstack need not be mindful of platform specific stack
	 * alignment.  Second, if we took this signal because the stack
	 * is not aligned properly, we'd like to take the signal cleanly
	 * and report that.
	 */
	sp &= ~15UL;

	return (void __user *) sp;
}

static inline int
setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
	       int signo, sigset_t *oldset, siginfo_t *info)
{
	struct rt_signal_frame __user *sf;
	int wsaved, err, sf_size;
	void __user *tail;

	/* 1. Make sure everything is clean */
	synchronize_user_stack();
	save_and_clear_fpu();
	
	wsaved = get_thread_wsaved();

	sf_size = sizeof(struct rt_signal_frame);
	if (current_thread_info()->fpsaved[0] & FPRS_FEF)
		sf_size += sizeof(__siginfo_fpu_t);
	if (wsaved)
		sf_size += sizeof(__siginfo_rwin_t);
	sf = (struct rt_signal_frame __user *)
		get_sigframe(ka, regs, sf_size);

	if (invalid_frame_pointer (sf))
		goto sigill;

	tail = (sf + 1);

	/* 2. Save the current process state */
	err = copy_to_user(&sf->regs, regs, sizeof (*regs));

	if (current_thread_info()->fpsaved[0] & FPRS_FEF) {
		__siginfo_fpu_t __user *fpu_save = tail;
		tail += sizeof(__siginfo_fpu_t);
		err |= save_fpu_state(regs, fpu_save);
		err |= __put_user((u64)fpu_save, &sf->fpu_save);
	} else {
		err |= __put_user(0, &sf->fpu_save);
	}
	if (wsaved) {
		__siginfo_rwin_t __user *rwin_save = tail;
		tail += sizeof(__siginfo_rwin_t);
		err |= save_rwin_state(wsaved, rwin_save);
		err |= __put_user((u64)rwin_save, &sf->rwin_save);
		set_thread_wsaved(0);
	} else {
		err |= __put_user(0, &sf->rwin_save);
	}
	
	/* Setup sigaltstack */
	err |= __put_user(current->sas_ss_sp, &sf->stack.ss_sp);
	err |= __put_user(sas_ss_flags(regs->u_regs[UREG_FP]), &sf->stack.ss_flags);
	err |= __put_user(current->sas_ss_size, &sf->stack.ss_size);

	err |= copy_to_user(&sf->mask, oldset, sizeof(sigset_t));

	if (!wsaved) {
		err |= copy_in_user((u64 __user *)sf,
				    (u64 __user *)(regs->u_regs[UREG_FP] +
						   STACK_BIAS),
				    sizeof(struct reg_window));
	} else {
		struct reg_window *rp;

		rp = &current_thread_info()->reg_window[wsaved - 1];
		err |= copy_to_user(sf, rp, sizeof(struct reg_window));
	}
	if (info)
		err |= copy_siginfo_to_user(&sf->info, info);
	else {
		err |= __put_user(signo, &sf->info.si_signo);
		err |= __put_user(SI_NOINFO, &sf->info.si_code);
	}
	if (err)
		goto sigsegv;
	
	/* 3. signal handler back-trampoline and parameters */
	regs->u_regs[UREG_FP] = ((unsigned long) sf) - STACK_BIAS;
	regs->u_regs[UREG_I0] = signo;
	regs->u_regs[UREG_I1] = (unsigned long) &sf->info;

	/* The sigcontext is passed in this way because of how it
	 * is defined in GLIBC's /usr/include/bits/sigcontext.h
	 * for sparc64.  It includes the 128 bytes of siginfo_t.
	 */
	regs->u_regs[UREG_I2] = (unsigned long) &sf->info;

	/* 5. signal handler */
	regs->tpc = (unsigned long) ka->sa.sa_handler;
	regs->tnpc = (regs->tpc + 4);
	if (test_thread_flag(TIF_32BIT)) {
		regs->tpc &= 0xffffffff;
		regs->tnpc &= 0xffffffff;
	}
	/* 4. return to kernel instructions */
	regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer;
	return 0;

sigill:
	do_exit(SIGILL);
	return -EINVAL;

sigsegv:
	force_sigsegv(signo, current);
	return -EFAULT;
}

static inline void handle_signal(unsigned long signr, struct k_sigaction *ka,
				siginfo_t *info,
				sigset_t *oldset, struct pt_regs *regs)
{
	int err;

	err = setup_rt_frame(ka, regs, signr, oldset,
			     (ka->sa.sa_flags & SA_SIGINFO) ? info : NULL);
	if (err)
		return;

	block_sigmask(ka, signr);
	tracehook_signal_handler(signr, info, ka, regs, 0);
}

static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs,
				   struct sigaction *sa)
{
	switch (regs->u_regs[UREG_I0]) {
	case ERESTART_RESTARTBLOCK:
	case ERESTARTNOHAND:
	no_system_call_restart:
		regs->u_regs[UREG_I0] = EINTR;
		regs->tstate |= (TSTATE_ICARRY|TSTATE_XCARRY);
		break;
	case ERESTARTSYS:
		if (!(sa->sa_flags & SA_RESTART))
			goto no_system_call_restart;
		/* fallthrough */
	case ERESTARTNOINTR:
		regs->u_regs[UREG_I0] = orig_i0;
		regs->tpc -= 4;
		regs->tnpc -= 4;
	}
}

/* Note that 'init' is a special process: it doesn't get signals it doesn't
 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 * mistake.
 */
static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
{
	struct k_sigaction ka;
	int restart_syscall;
	sigset_t *oldset = sigmask_to_save();
	siginfo_t info;
	int signr;
	
	/* It's a lot of work and synchronization to add a new ptrace
	 * register for GDB to save and restore in order to get
	 * orig_i0 correct for syscall restarts when debugging.
	 *
	 * Although it should be the case that most of the global
	 * registers are volatile across a system call, glibc already
	 * depends upon that fact that we preserve them.  So we can't
	 * just use any global register to save away the orig_i0 value.
	 *
	 * In particular %g2, %g3, %g4, and %g5 are all assumed to be
	 * preserved across a system call trap by various pieces of
	 * code in glibc.
	 *
	 * %g7 is used as the "thread register".   %g6 is not used in
	 * any fixed manner.  %g6 is used as a scratch register and
	 * a compiler temporary, but it's value is never used across
	 * a system call.  Therefore %g6 is usable for orig_i0 storage.
	 */
	if (pt_regs_is_syscall(regs) &&
	    (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY)))
		regs->u_regs[UREG_G6] = orig_i0;

#ifdef CONFIG_COMPAT
	if (test_thread_flag(TIF_32BIT)) {
		extern void do_signal32(sigset_t *, struct pt_regs *);
		do_signal32(oldset, regs);
		return;
	}
#endif	

	signr = get_signal_to_deliver(&info, &ka, regs, NULL);

	restart_syscall = 0;
	if (pt_regs_is_syscall(regs) &&
	    (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
		restart_syscall = 1;
		orig_i0 = regs->u_regs[UREG_G6];
	}

	if (signr > 0) {
		if (restart_syscall)
			syscall_restart(orig_i0, regs, &ka.sa);
		handle_signal(signr, &ka, &info, oldset, regs);
		return;
	}
	if (restart_syscall &&
	    (regs->u_regs[UREG_I0] == ERESTARTNOHAND ||
	     regs->u_regs[UREG_I0] == ERESTARTSYS ||
	     regs->u_regs[UREG_I0] == ERESTARTNOINTR)) {
		/* replay the system call when we are done */
		regs->u_regs[UREG_I0] = orig_i0;
		regs->tpc -= 4;
		regs->tnpc -= 4;
		pt_regs_clear_syscall(regs);
	}
	if (restart_syscall &&
	    regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
		regs->u_regs[UREG_G1] = __NR_restart_syscall;
		regs->tpc -= 4;
		regs->tnpc -= 4;
		pt_regs_clear_syscall(regs);
	}

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

void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0, unsigned long thread_info_flags)
{
	if (thread_info_flags & _TIF_SIGPENDING)
		do_signal(regs, orig_i0);
	if (thread_info_flags & _TIF_NOTIFY_RESUME) {
		clear_thread_flag(TIF_NOTIFY_RESUME);
		tracehook_notify_resume(regs);
	}
}
Commit	Line	Data
b00dc837	1	/*
1da177e4 LT	2	* arch/sparc64/kernel/signal.c
	3	*
	4	* Copyright (C) 1991, 1992 Linus Torvalds
0a4949c4	5	* Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net)
1da177e4 LT	6	* Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
	7	* Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
	8	* Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
	9	*/
	10
09337f50	11	#ifdef CONFIG_COMPAT
1da177e4 LT	12	#include <linux/compat.h> /* for compat_old_sigset_t */
	13	#endif
	14	#include <linux/sched.h>
	15	#include <linux/kernel.h>
	16	#include <linux/signal.h>
	17	#include <linux/errno.h>
	18	#include <linux/wait.h>
	19	#include <linux/ptrace.h>
e35a8925	20	#include <linux/tracehook.h>
1da177e4 LT	21	#include <linux/unistd.h>
	22	#include <linux/mm.h>
	23	#include <linux/tty.h>
1da177e4 LT	24	#include <linux/binfmts.h>
	25	#include <linux/bitops.h>
	26
	27	#include <asm/uaccess.h>
	28	#include <asm/ptrace.h>
1da177e4 LT	29	#include <asm/pgtable.h>
	30	#include <asm/fpumacro.h>
	31	#include <asm/uctx.h>
	32	#include <asm/siginfo.h>
	33	#include <asm/visasm.h>
d550bbd4 DH	34	#include <asm/switch_to.h>
d550bbd4 DH	35	#include <asm/cacheflush.h>
1da177e4	36
062ea6d3 DM	37	#include "entry.h"
062ea6d3 DM	38	#include "systbls.h"
5598473a	39	#include "sigutil.h"
062ea6d3	40
1da177e4 LT	41	/* {set, get}context() needed for 64-bit SparcLinux userland. */
	42	asmlinkage void sparc64_set_context(struct pt_regs *regs)
	43	{
	44	struct ucontext __user ucp = (struct ucontext __user )
	45	regs->u_regs[UREG_I0];
	46	mc_gregset_t __user *grp;
	47	unsigned long pc, npc, tstate;
	48	unsigned long fp, i7;
	49	unsigned char fenab;
	50	int err;
	51
	52	flush_user_windows();
	53	if (get_thread_wsaved() \|\|
	54	(((unsigned long)ucp) & (sizeof(unsigned long)-1)) \|\|
	55	(!__access_ok(ucp, sizeof(*ucp))))
	56	goto do_sigsegv;
	57	grp = &ucp->uc_mcontext.mc_gregs;
	58	err = __get_user(pc, &((*grp)[MC_PC]));
	59	err \|= __get_user(npc, &((*grp)[MC_NPC]));
	60	if (err \|\| ((pc \| npc) & 3))
	61	goto do_sigsegv;
	62	if (regs->u_regs[UREG_I1]) {
	63	sigset_t set;
	64
	65	if (_NSIG_WORDS == 1) {
	66	if (__get_user(set.sig[0], &ucp->uc_sigmask.sig[0]))
	67	goto do_sigsegv;
	68	} else {
	69	if (__copy_from_user(&set, &ucp->uc_sigmask, sizeof(sigset_t)))
	70	goto do_sigsegv;
	71	}
faddf598	72	set_current_blocked(&set);
1da177e4 LT	73	}
	74	if (test_thread_flag(TIF_32BIT)) {
	75	pc &= 0xffffffff;
	76	npc &= 0xffffffff;
	77	}
	78	regs->tpc = pc;
	79	regs->tnpc = npc;
	80	err \|= __get_user(regs->y, &((*grp)[MC_Y]));
	81	err \|= __get_user(tstate, &((*grp)[MC_TSTATE]));
	82	regs->tstate &= ~(TSTATE_ASI \| TSTATE_ICC \| TSTATE_XCC);
	83	regs->tstate \|= (tstate & (TSTATE_ASI \| TSTATE_ICC \| TSTATE_XCC));
	84	err \|= __get_user(regs->u_regs[UREG_G1], (&(*grp)[MC_G1]));
	85	err \|= __get_user(regs->u_regs[UREG_G2], (&(*grp)[MC_G2]));
	86	err \|= __get_user(regs->u_regs[UREG_G3], (&(*grp)[MC_G3]));
	87	err \|= __get_user(regs->u_regs[UREG_G4], (&(*grp)[MC_G4]));
	88	err \|= __get_user(regs->u_regs[UREG_G5], (&(*grp)[MC_G5]));
	89	err \|= __get_user(regs->u_regs[UREG_G6], (&(*grp)[MC_G6]));
0a4949c4 DM	90
	91	/* Skip %g7 as that's the thread register in userspace. */
	92
1da177e4 LT	93	err \|= __get_user(regs->u_regs[UREG_I0], (&(*grp)[MC_O0]));
	94	err \|= __get_user(regs->u_regs[UREG_I1], (&(*grp)[MC_O1]));
	95	err \|= __get_user(regs->u_regs[UREG_I2], (&(*grp)[MC_O2]));
	96	err \|= __get_user(regs->u_regs[UREG_I3], (&(*grp)[MC_O3]));
	97	err \|= __get_user(regs->u_regs[UREG_I4], (&(*grp)[MC_O4]));
	98	err \|= __get_user(regs->u_regs[UREG_I5], (&(*grp)[MC_O5]));
	99	err \|= __get_user(regs->u_regs[UREG_I6], (&(*grp)[MC_O6]));
	100	err \|= __get_user(regs->u_regs[UREG_I7], (&(*grp)[MC_O7]));
	101
	102	err \|= __get_user(fp, &(ucp->uc_mcontext.mc_fp));
	103	err \|= __get_user(i7, &(ucp->uc_mcontext.mc_i7));
	104	err \|= __put_user(fp,
	105	(&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
	106	err \|= __put_user(i7,
	107	(&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
	108
	109	err \|= __get_user(fenab, &(ucp->uc_mcontext.mc_fpregs.mcfpu_enab));
	110	if (fenab) {
	111	unsigned long *fpregs = current_thread_info()->fpregs;
	112	unsigned long fprs;
	113
	114	fprs_write(0);
	115	err \|= __get_user(fprs, &(ucp->uc_mcontext.mc_fpregs.mcfpu_fprs));
	116	if (fprs & FPRS_DL)
	117	err \|= copy_from_user(fpregs,
	118	&(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs),
	119	(sizeof(unsigned int) * 32));
	120	if (fprs & FPRS_DU)
	121	err \|= copy_from_user(fpregs+16,
	122	((unsigned long __user *)&(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs))+16,
	123	(sizeof(unsigned int) * 32));
	124	err \|= __get_user(current_thread_info()->xfsr[0],
	125	&(ucp->uc_mcontext.mc_fpregs.mcfpu_fsr));
	126	err \|= __get_user(current_thread_info()->gsr[0],
	127	&(ucp->uc_mcontext.mc_fpregs.mcfpu_gsr));
	128	regs->tstate &= ~TSTATE_PEF;
	129	}
	130	if (err)
	131	goto do_sigsegv;
	132
	133	return;
	134	do_sigsegv:
	135	force_sig(SIGSEGV, current);
	136	}
	137
	138	asmlinkage void sparc64_get_context(struct pt_regs *regs)
	139	{
	140	struct ucontext __user ucp = (struct ucontext __user )
	141	regs->u_regs[UREG_I0];
	142	mc_gregset_t __user *grp;
	143	mcontext_t __user *mcp;
	144	unsigned long fp, i7;
	145	unsigned char fenab;
	146	int err;
	147
	148	synchronize_user_stack();
	149	if (get_thread_wsaved() \|\| clear_user(ucp, sizeof(*ucp)))
	150	goto do_sigsegv;
	151
	152	#if 1
	153	fenab = 0; /* IMO get_context is like any other system call, thus modifies FPU state -jj */
	154	#else
	155	fenab = (current_thread_info()->fpsaved[0] & FPRS_FEF);
	156	#endif
157
158	mcp = &ucp->uc_mcontext;
159	grp = &mcp->mc_gregs;
160
161	/* Skip over the trap instruction, first. */
162	if (test_thread_flag(TIF_32BIT)) {
163	regs->tpc = (regs->tnpc & 0xffffffff);
164	regs->tnpc = (regs->tnpc + 4) & 0xffffffff;
165	} else {
166	regs->tpc = regs->tnpc;
167	regs->tnpc += 4;
168	}
169	err = 0;
170	if (_NSIG_WORDS == 1)
171	err \|= __put_user(current->blocked.sig[0],
172	(unsigned long __user *)&ucp->uc_sigmask);
173	else
174	err \|= __copy_to_user(&ucp->uc_sigmask, &current->blocked,
175	sizeof(sigset_t));
176
177	err \|= __put_user(regs->tstate, &((*grp)[MC_TSTATE]));
178	err \|= __put_user(regs->tpc, &((*grp)[MC_PC]));
179	err \|= __put_user(regs->tnpc, &((*grp)[MC_NPC]));
180	err \|= __put_user(regs->y, &((*grp)[MC_Y]));
181	err \|= __put_user(regs->u_regs[UREG_G1], &((*grp)[MC_G1]));
182	err \|= __put_user(regs->u_regs[UREG_G2], &((*grp)[MC_G2]));
183	err \|= __put_user(regs->u_regs[UREG_G3], &((*grp)[MC_G3]));
184	err \|= __put_user(regs->u_regs[UREG_G4], &((*grp)[MC_G4]));
185	err \|= __put_user(regs->u_regs[UREG_G5], &((*grp)[MC_G5]));
186	err \|= __put_user(regs->u_regs[UREG_G6], &((*grp)[MC_G6]));
187	err \|= __put_user(regs->u_regs[UREG_G7], &((*grp)[MC_G7]));
188	err \|= __put_user(regs->u_regs[UREG_I0], &((*grp)[MC_O0]));
189	err \|= __put_user(regs->u_regs[UREG_I1], &((*grp)[MC_O1]));
190	err \|= __put_user(regs->u_regs[UREG_I2], &((*grp)[MC_O2]));
191	err \|= __put_user(regs->u_regs[UREG_I3], &((*grp)[MC_O3]));
192	err \|= __put_user(regs->u_regs[UREG_I4], &((*grp)[MC_O4]));
193	err \|= __put_user(regs->u_regs[UREG_I5], &((*grp)[MC_O5]));
194	err \|= __put_user(regs->u_regs[UREG_I6], &((*grp)[MC_O6]));
195	err \|= __put_user(regs->u_regs[UREG_I7], &((*grp)[MC_O7]));
196
197	err \|= __get_user(fp,
198	(&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
199	err \|= __get_user(i7,
200	(&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
201	err \|= __put_user(fp, &(mcp->mc_fp));
202	err \|= __put_user(i7, &(mcp->mc_i7));
203
204	err \|= __put_user(fenab, &(mcp->mc_fpregs.mcfpu_enab));
205	if (fenab) {
206	unsigned long *fpregs = current_thread_info()->fpregs;
207	unsigned long fprs;
208
209	fprs = current_thread_info()->fpsaved[0];
210	if (fprs & FPRS_DL)
211	err \|= copy_to_user(&(mcp->mc_fpregs.mcfpu_fregs), fpregs,
212	(sizeof(unsigned int) * 32));
213	if (fprs & FPRS_DU)
214	err \|= copy_to_user(
215	((unsigned long __user *)&(mcp->mc_fpregs.mcfpu_fregs))+16, fpregs+16,
216	(sizeof(unsigned int) * 32));
217	err \|= __put_user(current_thread_info()->xfsr[0], &(mcp->mc_fpregs.mcfpu_fsr));
218	err \|= __put_user(current_thread_info()->gsr[0], &(mcp->mc_fpregs.mcfpu_gsr));
219	err \|= __put_user(fprs, &(mcp->mc_fpregs.mcfpu_fprs));
220	}
221	if (err)
222	goto do_sigsegv;
223
224	return;
225	do_sigsegv:
226	force_sig(SIGSEGV, current);
227	}
228
229	struct rt_signal_frame {
230	struct sparc_stackf ss;
231	siginfo_t info;
232	struct pt_regs regs;
233	__siginfo_fpu_t __user *fpu_save;
234	stack_t stack;
235	sigset_t mask;
5598473a	236	__siginfo_rwin_t *rwin_save;
1da177e4 LT	237	};
1da177e4 LT	238
2d7d5f05	239	static long _sigpause_common(old_sigset_t set)
1da177e4	240	{
faddf598	241	sigset_t blocked;
faddf598	242	siginitset(&blocked, set);
68f3f16d	243	return sigsuspend(&blocked);
1da177e4 LT	244	}
1da177e4 LT	245
2d7d5f05	246	asmlinkage long sys_sigpause(unsigned int set)
1da177e4	247	{
2d7d5f05	248	return _sigpause_common(set);
1da177e4 LT	249	}
1da177e4 LT	250
2d7d5f05	251	asmlinkage long sys_sigsuspend(old_sigset_t set)
1da177e4	252	{
2d7d5f05	253	return _sigpause_common(set);
1da177e4 LT	254	}
1da177e4 LT	255
1da177e4 LT	256	void do_rt_sigreturn(struct pt_regs *regs)
	257	{
	258	struct rt_signal_frame __user *sf;
	259	unsigned long tpc, tnpc, tstate;
	260	__siginfo_fpu_t __user *fpu_save;
5598473a	261	__siginfo_rwin_t __user *rwin_save;
1da177e4	262	sigset_t set;
1da177e4 LT	263	int err;
	264
	265	/* Always make any pending restarted system calls return -EINTR */
	266	current_thread_info()->restart_block.fn = do_no_restart_syscall;
	267
	268	synchronize_user_stack ();
	269	sf = (struct rt_signal_frame __user *)
	270	(regs->u_regs [UREG_FP] + STACK_BIAS);
	271
	272	/* 1. Make sure we are not getting garbage from the user */
	273	if (((unsigned long) sf) & 3)
	274	goto segv;
	275
	276	err = get_user(tpc, &sf->regs.tpc);
	277	err \|= __get_user(tnpc, &sf->regs.tnpc);
	278	if (test_thread_flag(TIF_32BIT)) {
	279	tpc &= 0xffffffff;
	280	tnpc &= 0xffffffff;
	281	}
	282	err \|= ((tpc \| tnpc) & 3);
	283
	284	/* 2. Restore the state */
	285	err \|= __get_user(regs->y, &sf->regs.y);
	286	err \|= __get_user(tstate, &sf->regs.tstate);
	287	err \|= copy_from_user(regs->u_regs, sf->regs.u_regs, sizeof(regs->u_regs));
	288
	289	/* User can only change condition codes and %asi in %tstate. */
	290	regs->tstate &= ~(TSTATE_ASI \| TSTATE_ICC \| TSTATE_XCC);
	291	regs->tstate \|= (tstate & (TSTATE_ASI \| TSTATE_ICC \| TSTATE_XCC));
	292
	293	err \|= __get_user(fpu_save, &sf->fpu_save);
5598473a DM	294	if (!err && fpu_save)
5598473a DM	295	err \|= restore_fpu_state(regs, fpu_save);
1da177e4 LT	296
1da177e4 LT	297	err \|= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
62715ec8 ON	298	err \|= do_sigaltstack(&sf->stack, NULL, (unsigned long)sf);
62715ec8 ON	299
1da177e4 LT	300	if (err)
1da177e4 LT	301	goto segv;
62715ec8	302
5598473a DM	303	err \|= __get_user(rwin_save, &sf->rwin_save);
	304	if (!err && rwin_save) {
	305	if (restore_rwin_state(rwin_save))
	306	goto segv;
	307	}
	308
1da177e4 LT	309	regs->tpc = tpc;
1da177e4 LT	310	regs->tnpc = tnpc;
1da177e4	311
2678fefe	312	/* Prevent syscall restart. */
28e61036	313	pt_regs_clear_syscall(regs);
2678fefe	314
faddf598	315	set_current_blocked(&set);
1da177e4 LT	316	return;
	317	segv:
	318	force_sig(SIGSEGV, current);
	319	}
	320
	321	/* Checks if the fp is valid */
5598473a	322	static int invalid_frame_pointer(void __user *fp)
1da177e4	323	{
f036d9f3	324	if (((unsigned long) fp) & 15)
1da177e4 LT	325	return 1;
	326	return 0;
	327	}
	328
1da177e4 LT	329	static inline void __user get_sigframe(struct k_sigaction ka, struct pt_regs *regs, unsigned long framesize)
1da177e4 LT	330	{
dc5dc7e6	331	unsigned long sp = regs->u_regs[UREG_FP] + STACK_BIAS;
1da177e4	332
dc5dc7e6 DM	333	/*
	334	* If we are on the alternate signal stack and would overflow it, don't.
	335	* Return an always-bogus address instead so we will die with SIGSEGV.
	336	*/
	337	if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize)))
	338	return (void __user *) -1L;
1da177e4 LT	339
	340	/* This is the X/Open sanctioned signal stack switching. */
	341	if (ka->sa.sa_flags & SA_ONSTACK) {
dc5dc7e6	342	if (sas_ss_flags(sp) == 0)
1da177e4 LT	343	sp = current->sas_ss_sp + current->sas_ss_size;
1da177e4 LT	344	}
dc5dc7e6	345
f036d9f3 DM	346	sp -= framesize;
f036d9f3 DM	347
dc5dc7e6 DM	348	/* Always align the stack frame. This handles two cases. First,
	349	* sigaltstack need not be mindful of platform specific stack
	350	* alignment. Second, if we took this signal because the stack
	351	* is not aligned properly, we'd like to take the signal cleanly
	352	* and report that.
	353	*/
f036d9f3	354	sp &= ~15UL;
dc5dc7e6	355
f036d9f3	356	return (void __user *) sp;
1da177e4 LT	357	}
1da177e4 LT	358
392c2180	359	static inline int
1da177e4 LT	360	setup_rt_frame(struct k_sigaction ka, struct pt_regs regs,
	361	int signo, sigset_t oldset, siginfo_t info)
	362	{
	363	struct rt_signal_frame __user *sf;
5598473a DM	364	int wsaved, err, sf_size;
5598473a DM	365	void __user *tail;
1da177e4 LT	366
	367	/* 1. Make sure everything is clean */
	368	synchronize_user_stack();
	369	save_and_clear_fpu();
	370
5598473a	371	wsaved = get_thread_wsaved();
1da177e4	372
5598473a DM	373	sf_size = sizeof(struct rt_signal_frame);
	374	if (current_thread_info()->fpsaved[0] & FPRS_FEF)
	375	sf_size += sizeof(__siginfo_fpu_t);
	376	if (wsaved)
	377	sf_size += sizeof(__siginfo_rwin_t);
1da177e4	378	sf = (struct rt_signal_frame __user *)
5598473a	379	get_sigframe(ka, regs, sf_size);
1da177e4	380
5598473a	381	if (invalid_frame_pointer (sf))
1da177e4 LT	382	goto sigill;
1da177e4 LT	383
5598473a DM	384	tail = (sf + 1);
5598473a DM	385
1da177e4 LT	386	/* 2. Save the current process state */
	387	err = copy_to_user(&sf->regs, regs, sizeof (*regs));
	388
	389	if (current_thread_info()->fpsaved[0] & FPRS_FEF) {
5598473a DM	390	__siginfo_fpu_t __user *fpu_save = tail;
	391	tail += sizeof(__siginfo_fpu_t);
	392	err \|= save_fpu_state(regs, fpu_save);
	393	err \|= __put_user((u64)fpu_save, &sf->fpu_save);
1da177e4 LT	394	} else {
	395	err \|= __put_user(0, &sf->fpu_save);
	396	}
5598473a DM	397	if (wsaved) {
	398	__siginfo_rwin_t __user *rwin_save = tail;
	399	tail += sizeof(__siginfo_rwin_t);
	400	err \|= save_rwin_state(wsaved, rwin_save);
	401	err \|= __put_user((u64)rwin_save, &sf->rwin_save);
	402	set_thread_wsaved(0);
	403	} else {
	404	err \|= __put_user(0, &sf->rwin_save);
	405	}
1da177e4 LT	406
	407	/* Setup sigaltstack */
	408	err \|= __put_user(current->sas_ss_sp, &sf->stack.ss_sp);
	409	err \|= __put_user(sas_ss_flags(regs->u_regs[UREG_FP]), &sf->stack.ss_flags);
	410	err \|= __put_user(current->sas_ss_size, &sf->stack.ss_size);
	411
	412	err \|= copy_to_user(&sf->mask, oldset, sizeof(sigset_t));
	413
5598473a DM	414	if (!wsaved) {
	415	err \|= copy_in_user((u64 __user *)sf,
	416	(u64 __user *)(regs->u_regs[UREG_FP] +
	417	STACK_BIAS),
	418	sizeof(struct reg_window));
	419	} else {
	420	struct reg_window *rp;
1da177e4	421
5598473a DM	422	rp = &current_thread_info()->reg_window[wsaved - 1];
	423	err \|= copy_to_user(sf, rp, sizeof(struct reg_window));
	424	}
1da177e4 LT	425	if (info)
	426	err \|= copy_siginfo_to_user(&sf->info, info);
	427	else {
	428	err \|= __put_user(signo, &sf->info.si_signo);
	429	err \|= __put_user(SI_NOINFO, &sf->info.si_code);
	430	}
	431	if (err)
	432	goto sigsegv;
	433
	434	/* 3. signal handler back-trampoline and parameters */
	435	regs->u_regs[UREG_FP] = ((unsigned long) sf) - STACK_BIAS;
	436	regs->u_regs[UREG_I0] = signo;
	437	regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
	438
	439	/* The sigcontext is passed in this way because of how it
	440	* is defined in GLIBC's /usr/include/bits/sigcontext.h
	441	* for sparc64. It includes the 128 bytes of siginfo_t.
	442	*/
	443	regs->u_regs[UREG_I2] = (unsigned long) &sf->info;
	444
	445	/* 5. signal handler */
	446	regs->tpc = (unsigned long) ka->sa.sa_handler;
	447	regs->tnpc = (regs->tpc + 4);
	448	if (test_thread_flag(TIF_32BIT)) {
	449	regs->tpc &= 0xffffffff;
	450	regs->tnpc &= 0xffffffff;
	451	}
	452	/* 4. return to kernel instructions */
	453	regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer;
392c2180	454	return 0;
1da177e4 LT	455
	456	sigill:
	457	do_exit(SIGILL);
392c2180 DM	458	return -EINVAL;
392c2180 DM	459
1da177e4 LT	460	sigsegv:
1da177e4 LT	461	force_sigsegv(signo, current);
392c2180	462	return -EFAULT;
1da177e4 LT	463	}
1da177e4 LT	464
a610d6e6	465	static inline void handle_signal(unsigned long signr, struct k_sigaction *ka,
392c2180 DM	466	siginfo_t *info,
392c2180 DM	467	sigset_t oldset, struct pt_regs regs)
1da177e4	468	{
392c2180 DM	469	int err;
	470
	471	err = setup_rt_frame(ka, regs, signr, oldset,
	472	(ka->sa.sa_flags & SA_SIGINFO) ? info : NULL);
	473	if (err)
a610d6e6	474	return;
392c2180	475
ce24d8a1	476	block_sigmask(ka, signr);
392c2180	477	tracehook_signal_handler(signr, info, ka, regs, 0);
1da177e4 LT	478	}
	479
	480	static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs,
28e61036	481	struct sigaction *sa)
1da177e4 LT	482	{
	483	switch (regs->u_regs[UREG_I0]) {
	484	case ERESTART_RESTARTBLOCK:
	485	case ERESTARTNOHAND:
	486	no_system_call_restart:
	487	regs->u_regs[UREG_I0] = EINTR;
	488	regs->tstate \|= (TSTATE_ICARRY\|TSTATE_XCARRY);
	489	break;
	490	case ERESTARTSYS:
	491	if (!(sa->sa_flags & SA_RESTART))
	492	goto no_system_call_restart;
	493	/* fallthrough */
	494	case ERESTARTNOINTR:
	495	regs->u_regs[UREG_I0] = orig_i0;
	496	regs->tpc -= 4;
	497	regs->tnpc -= 4;
	498	}
	499	}
	500
	501	/* Note that 'init' is a special process: it doesn't get signals it doesn't
	502	* want to handle. Thus you cannot kill init even with a SIGKILL even by
	503	* mistake.
	504	*/
238468b2	505	static void do_signal(struct pt_regs *regs, unsigned long orig_i0)
1da177e4	506	{
1da177e4	507	struct k_sigaction ka;
28e61036	508	int restart_syscall;
b7f9a11a	509	sigset_t *oldset = sigmask_to_save();
238468b2	510	siginfo_t info;
90888816	511	int signr;
1da177e4	512
1d299bc7 DM	513	/* It's a lot of work and synchronization to add a new ptrace
	514	* register for GDB to save and restore in order to get
	515	* orig_i0 correct for syscall restarts when debugging.
	516	*
e88d2468 DM	517	* Although it should be the case that most of the global
	518	* registers are volatile across a system call, glibc already
	519	* depends upon that fact that we preserve them. So we can't
	520	* just use any global register to save away the orig_i0 value.
	521	*
	522	* In particular %g2, %g3, %g4, and %g5 are all assumed to be
	523	* preserved across a system call trap by various pieces of
	524	* code in glibc.
	525	*
	526	* %g7 is used as the "thread register". %g6 is not used in
	527	* any fixed manner. %g6 is used as a scratch register and
	528	* a compiler temporary, but it's value is never used across
	529	* a system call. Therefore %g6 is usable for orig_i0 storage.
1d299bc7	530	*/
2678fefe	531	if (pt_regs_is_syscall(regs) &&
1d299bc7	532	(regs->tstate & (TSTATE_XCARRY \| TSTATE_ICARRY)))
e88d2468	533	regs->u_regs[UREG_G6] = orig_i0;
1da177e4	534
09337f50	535	#ifdef CONFIG_COMPAT
1da177e4	536	if (test_thread_flag(TIF_32BIT)) {
1d299bc7 DM	537	extern void do_signal32(sigset_t , struct pt_regs );
1d299bc7 DM	538	do_signal32(oldset, regs);
2d7d5f05	539	return;
1da177e4 LT	540	}
	541	#endif
	542
28e61036 DM	543	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
28e61036 DM	544
1d299bc7 DM	545	restart_syscall = 0;
	546	if (pt_regs_is_syscall(regs) &&
	547	(regs->tstate & (TSTATE_XCARRY \| TSTATE_ICARRY))) {
	548	restart_syscall = 1;
e88d2468	549	orig_i0 = regs->u_regs[UREG_G6];
1d299bc7	550	}
28e61036	551
1da177e4	552	if (signr > 0) {
28e61036 DM	553	if (restart_syscall)
28e61036 DM	554	syscall_restart(orig_i0, regs, &ka.sa);
a610d6e6	555	handle_signal(signr, &ka, &info, oldset, regs);
2d7d5f05	556	return;
1da177e4	557	}
28e61036	558	if (restart_syscall &&
1da177e4 LT	559	(regs->u_regs[UREG_I0] == ERESTARTNOHAND \|\|
	560	regs->u_regs[UREG_I0] == ERESTARTSYS \|\|
	561	regs->u_regs[UREG_I0] == ERESTARTNOINTR)) {
	562	/* replay the system call when we are done */
28e61036	563	regs->u_regs[UREG_I0] = orig_i0;
1da177e4 LT	564	regs->tpc -= 4;
1da177e4 LT	565	regs->tnpc -= 4;
c2785259	566	pt_regs_clear_syscall(regs);
1da177e4	567	}
28e61036	568	if (restart_syscall &&
1da177e4 LT	569	regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
	570	regs->u_regs[UREG_G1] = __NR_restart_syscall;
	571	regs->tpc -= 4;
	572	regs->tnpc -= 4;
c2785259	573	pt_regs_clear_syscall(regs);
1da177e4	574	}
2d7d5f05	575
9a28dbf8	576	/* If there's no signal to deliver, we just put the saved sigmask
2d7d5f05 DM	577	* back
2d7d5f05 DM	578	*/
51a7b448	579	restore_saved_sigmask();
1da177e4 LT	580	}
1da177e4 LT	581
7697daaa	582	void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0, unsigned long thread_info_flags)
1da177e4	583	{
9a28dbf8	584	if (thread_info_flags & _TIF_SIGPENDING)
238468b2	585	do_signal(regs, orig_i0);
e35a8925 RM	586	if (thread_info_flags & _TIF_NOTIFY_RESUME) {
	587	clear_thread_flag(TIF_NOTIFY_RESUME);
	588	tracehook_notify_resume(regs);
	589	}
1da177e4	590	}
ee18d64c	591