patch-2.4.21 linux-2.4.21/arch/ppc64/kernel/signal.c

• Lines: 989
• Date: 2003-06-13 07:51:32.000000000 -0700
• Orig file: linux-2.4.20/arch/ppc64/kernel/signal.c
• Orig date: 2002-11-28 15:53:11.000000000 -0800

diff -urN linux-2.4.20/arch/ppc64/kernel/signal.c linux-2.4.21/arch/ppc64/kernel/signal.c
@@ -43,24 +43,44 @@
 #endif
 
 #define GP_REGS_SIZE	MIN(sizeof(elf_gregset_t), sizeof(struct pt_regs))
+#define FP_REGS_SIZE	sizeof(elf_fpregset_t)
 
-/* 
- * These are the flags in the MSR that the user is allowed to change
- * by modifying the saved value of the MSR on the stack.  SE and BE
- * should not be in this list since gdb may want to change these.  I.e,
- * you should be able to step out of a signal handler to see what
- * instruction executes next after the signal handler completes.
- * Alternately, if you stepped into a signal handler, you should be
- * able to continue 'til the next breakpoint from within the signal
- * handler, even if the handler returns.
+#define TRAMP_TRACEBACK	3
+#define TRAMP_SIZE	6
+
+/*
+ * When we have signals to deliver, we set up on the user stack,
+ * going down from the original stack pointer:
+ *	1) a sigframe/rt_sigframe struct which contains the sigcontext/ucontext	
+ *	2) a gap of __SIGNAL_FRAMESIZE bytes which acts as a dummy caller
+ *	   frame for the signal handler.
  */
-#define MSR_USERCHANGE	(MSR_FE0 | MSR_FE1)
 
-int do_signal(sigset_t *oldset, struct pt_regs *regs);
+struct sigframe {
+	/* sys_sigreturn requires the sigcontext be the first field */
+	struct sigcontext sc;
+	unsigned int tramp[TRAMP_SIZE];
+	/* 64 bit ABI allows for 288 bytes below sp before decrementing it. */
+	char abigap[288];
+};
+
+struct rt_sigframe {
+	/* sys_rt_sigreturn requires the ucontext be the first field */
+	struct ucontext uc;
+	unsigned long _unused[2];
+	unsigned int tramp[TRAMP_SIZE];
+	struct siginfo *pinfo;
+	void *puc;
+	struct siginfo info;
+	/* 64 bit ABI allows for 288 bytes below sp before decrementing it. */
+	char abigap[288];
+};
+
 extern long sys_wait4(pid_t pid, unsigned int *stat_addr,
 		     int options, /*unsigned long*/ struct rusage *ru);
 
-int copy_siginfo_to_user(siginfo_t *to, siginfo_t *from)
+int
+copy_siginfo_to_user(siginfo_t *to, siginfo_t *from)
 {
 	if (!access_ok (VERIFY_WRITE, to, sizeof(siginfo_t)))
 		return -EFAULT;
@@ -95,18 +115,16 @@
 	}
 }
 
+int do_signal(sigset_t *oldset, struct pt_regs *regs);
+
 /*
  * Atomically swap in the new signal mask, and wait for a signal.
  */
-long sys_sigsuspend(old_sigset_t mask, int p2, int p3, int p4, int p6, int p7,
+asmlinkage long
+sys_sigsuspend(old_sigset_t mask, int p2, int p3, int p4, int p6, int p7,
 	       struct pt_regs *regs)
 {
 	sigset_t saveset;
-  
-        PPCDBG(PPCDBG_SYS64X, "sys_sigsuspend - running - pid=%ld current=%lx comm=%s \n",
-                current->pid, current, current->comm);
-
-
 
 	mask &= _BLOCKABLE;
 	spin_lock_irq(&current->sigmask_lock);
@@ -115,7 +133,9 @@
 	recalc_sigpending(current);
 	spin_unlock_irq(&current->sigmask_lock);
 
-	regs->gpr[3] = -EINTR;
+	regs->result = -EINTR;
+	regs->gpr[3] = EINTR;
+	regs->ccr |= 0x10000000;
 	while (1) {
 		current->state = TASK_INTERRUPTIBLE;
 		schedule();
@@ -132,16 +152,13 @@
 	}
 }
 
-long sys_rt_sigsuspend(sigset_t *unewset, size_t sigsetsize, int p3, int p4, int p6,
+asmlinkage long
+sys_rt_sigsuspend(sigset_t *unewset, size_t sigsetsize, int p3, int p4, int p6,
 		  int p7, struct pt_regs *regs)
 {
 	sigset_t saveset, newset;
 
-  
-        PPCDBG(PPCDBG_SYS64X, "sys_rt_sigsuspend - running - pid=%ld current=%lx comm=%s \n",
-                current->pid, current, current->comm);
-	
-  /* XXX: Don't preclude handling different sized sigset_t's.  */
+	/* XXX: Don't preclude handling different sized sigset_t's.  */
 	if (sigsetsize != sizeof(sigset_t))
 		return -EINVAL;
 
@@ -155,7 +172,9 @@
 	recalc_sigpending(current);
 	spin_unlock_irq(&current->sigmask_lock);
 
-	regs->gpr[3] = -EINTR;
+	regs->result = -EINTR;
+	regs->gpr[3] = EINTR;
+	regs->ccr |= 0x10000000;
 	while (1) {
 		current->state = TASK_INTERRUPTIBLE;
 		schedule();
@@ -164,31 +183,24 @@
 	}
 }
 
-
-
-asmlinkage long sys_sigaltstack(const stack_t *uss, stack_t *uoss)
+asmlinkage long
+sys_sigaltstack(const stack_t *uss, stack_t *uoss, unsigned long r5,
+		unsigned long r6, unsigned long r7, unsigned long r8,
+		struct pt_regs *regs)
 {
-  struct pt_regs *regs = (struct pt_regs *) &uss;
-  
-  PPCDBG(PPCDBG_SYS64X, "sys_sigaltstack - running - pid=%ld current=%lx comm=%s \n",
-          current->pid, current, current->comm);
-
-  return do_sigaltstack(uss, uoss, regs->gpr[1]);
+        return do_sigaltstack(uss, uoss, regs->gpr[1]);
 }
 
-long sys_sigaction(int sig, const struct old_sigaction *act,
+asmlinkage long
+sys_sigaction(int sig, const struct old_sigaction *act,
 	      struct old_sigaction *oact)
 {
 	struct k_sigaction new_ka, old_ka;
 	int ret;
 
-        PPCDBG(PPCDBG_SYS64X, "sys_sigaction - running - pid=%ld current=%lx comm=%s \n",
-                current->pid, current, current->comm);
-
- 
-
 	if (act) {
 		old_sigset_t mask;
+
 		if (verify_area(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))
@@ -199,7 +211,6 @@
 	}
 
 	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
-
 	if (!ret && oact) {
 		if (verify_area(VERIFY_WRITE, oact, sizeof(*oact)) ||
 		    __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
@@ -209,193 +220,212 @@
 		__put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
 	}
 
-
- 
-
 	return ret;
 }
 
 /*
- * When we have signals to deliver, we set up on the
- * user stack, going down from the original stack pointer:
- *	a sigregs struct
- *	one or more sigcontext structs
- *	a gap of __SIGNAL_FRAMESIZE bytes
- *
- * Each of these things must be a multiple of 16 bytes in size.
- *
- * XXX ultimately we will have to stack up a siginfo and ucontext
- * for each rt signal.
+ * Set up the sigcontext for the signal frame.
  */
-struct sigregs {
-	elf_gregset_t	gp_regs;
-	double		fp_regs[ELF_NFPREG];
-	unsigned int	tramp[2];
-	/* 64 bit API allows for 288 bytes below sp before 
-	   decrementing it. */
-	int		abigap[72];
-};
 
+static int
+setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs,
+		 int signr, sigset_t *set, unsigned long handler)
+{
+	int err = 0;
+
+	if (regs->msr & MSR_FP)
+		giveup_fpu(current);
+
+	current->thread.saved_msr = regs->msr & ~(MSR_FP | MSR_FE0 | MSR_FE1);
+	regs->msr = current->thread.saved_msr | current->thread.fpexc_mode;
+	current->thread.saved_softe = regs->softe;
+
+	err |= __put_user(&sc->gp_regs, &sc->regs);
+	err |= __copy_to_user(&sc->gp_regs, regs, GP_REGS_SIZE);
+	err |= __copy_to_user(&sc->fp_regs, &current->thread.fpr, FP_REGS_SIZE);
+	err |= __put_user(signr, &sc->signal);
+	err |= __put_user(handler, &sc->handler);
+	if (set != NULL)
+		err |=  __put_user(set->sig[0], &sc->oldmask);
 
+	regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
+	current->thread.fpscr = 0;
 
-struct rt_sigframe
+	return err;
+}
+
+/*
+ * Restore the sigcontext from the signal frame.
+ */
+
+static int
+restore_sigcontext(struct pt_regs *regs, sigset_t *set, struct sigcontext *sc)
 {
-	unsigned long	_unused[2];
-	struct siginfo *pinfo;
-	void *puc;
-	struct siginfo info;
-	struct ucontext uc;
-};
+	unsigned int err = 0;
 
+	if (regs->msr & MSR_FP)
+		giveup_fpu(current);
+
+	err |= __copy_from_user(regs, &sc->gp_regs, GP_REGS_SIZE);
+	err |= __copy_from_user(&current->thread.fpr, &sc->fp_regs, FP_REGS_SIZE);
+	current->thread.fpexc_mode = regs->msr & (MSR_FE0 | MSR_FE1);
+	if (set != NULL)
+		err |=  __get_user(set->sig[0], &sc->oldmask);
+
+	/* Don't allow the signal handler to change these modulo FE{0,1} */
+	regs->msr = current->thread.saved_msr & ~(MSR_FP | MSR_FE0 | MSR_FE1);
+	regs->softe = current->thread.saved_softe;
+
+	return err;
+}
 
 /*
- *  When we have rt signals to deliver, we set up on the
- *  user stack, going down from the original stack pointer:
- *	   a sigregs struct
- *	   one rt_sigframe struct (siginfo + ucontext)
- *	   a gap of __SIGNAL_FRAMESIZE bytes
- *
- *  Each of these things must be a multiple of 16 bytes in size.
- *
+ * Allocate space for the signal frame
  */
+static inline void *
+get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size)
+{
+        unsigned long newsp;
 
-int sys_rt_sigreturn(unsigned long r3, unsigned long r4, unsigned long r5,
-		     unsigned long r6, unsigned long r7, unsigned long r8,
-		     struct pt_regs *regs)
-{
-	struct rt_sigframe *rt_sf;
-	struct sigcontext_struct sigctx;
-	struct sigregs *sr;
-	int ret;
-	elf_gregset_t saved_regs;  /* an array of ELF_NGREG unsigned longs */
+        /* Default to using normal stack */
+        newsp = regs->gpr[1];
+
+	if (ka->sa.sa_flags & SA_ONSTACK) {
+		if (! on_sig_stack(regs->gpr[1]))
+			newsp = (current->sas_ss_sp + current->sas_ss_size);
+	}
+
+        return (void *)((newsp - frame_size) & -8ul);
+}
+
+static int
+setup_trampoline(unsigned int syscall, unsigned int *tramp)
+{
+	int i, err = 0;
+
+	/* addi r1, r1, __SIGNAL_FRAMESIZE  # Pop the dummy stackframe */
+	err |= __put_user(0x38210000UL | (__SIGNAL_FRAMESIZE & 0xffff), &tramp[0]);
+	/* li r0, __NR_[rt_]sigreturn| */
+	err |= __put_user(0x38000000UL | (syscall & 0xffff), &tramp[1]);
+	/* sc */
+	err |= __put_user(0x44000002UL, &tramp[2]);
+
+	/* Minimal traceback info */
+	for (i=TRAMP_TRACEBACK; i < TRAMP_SIZE ;i++)
+		err |= __put_user(0, &tramp[i]);
+
+	if (!err)
+		flush_icache_range((unsigned long) &tramp[0],
+			   (unsigned long) &tramp[TRAMP_SIZE]);
+
+	return err;
+}
+
+
+asmlinkage int
+sys_rt_sigreturn(unsigned long r3, unsigned long r4, unsigned long r5,
+		 unsigned long r6, unsigned long r7, unsigned long r8,
+		 struct pt_regs *regs)
+{
+	struct ucontext *uc = (struct ucontext *)regs->gpr[1];
 	sigset_t set;
 	stack_t st;
-	unsigned long prevsp;
 
-	rt_sf = (struct rt_sigframe *)(regs->gpr[1] + __SIGNAL_FRAMESIZE);
-	if (copy_from_user(&sigctx, &rt_sf->uc.uc_mcontext, sizeof(sigctx))
-	    || copy_from_user(&set, &rt_sf->uc.uc_sigmask, sizeof(set))
-	    || copy_from_user(&st, &rt_sf->uc.uc_stack, sizeof(st)))
+	if (verify_area(VERIFY_READ, uc, sizeof(*uc)))
 		goto badframe;
+
+	if (__copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
+		goto badframe;
+
 	sigdelsetmask(&set, ~_BLOCKABLE);
 	spin_lock_irq(&current->sigmask_lock);
 	current->blocked = set;
 	recalc_sigpending(current);
 	spin_unlock_irq(&current->sigmask_lock);
 
-	rt_sf++;			/* Look at next rt_sigframe */
-	if (rt_sf == (struct rt_sigframe *)(sigctx.regs)) {
-		/* Last stacked signal - restore registers -
-		 * sigctx is initialized to point to the 
-		 * preamble frame (where registers are stored) 
-		 * see handle_signal()
-		 */
-		sr = (struct sigregs *) sigctx.regs;
-		if (regs->msr & MSR_FP )
-			giveup_fpu(current);
-		if (copy_from_user(saved_regs, &sr->gp_regs,
-				   sizeof(sr->gp_regs)))
-			goto badframe;
-		saved_regs[PT_MSR] = (regs->msr & ~MSR_USERCHANGE)
-			| (saved_regs[PT_MSR] & MSR_USERCHANGE);
-		saved_regs[PT_SOFTE] = regs->softe;
-		memcpy(regs, saved_regs, GP_REGS_SIZE);
-		if (copy_from_user(current->thread.fpr, &sr->fp_regs,
-				   sizeof(sr->fp_regs)))
-			goto badframe;
-		/* This function sets back the stack flags into
-		   the current task structure.  */
-		sys_sigaltstack(&st, NULL);
-
-		ret = regs->result;
-	} else {
-		/* More signals to go */
-		/* Set up registers for next signal handler */
-		regs->gpr[1] = (unsigned long)rt_sf - __SIGNAL_FRAMESIZE;
-		if (copy_from_user(&sigctx, &rt_sf->uc.uc_mcontext, sizeof(sigctx)))
-			goto badframe;
-		sr = (struct sigregs *) sigctx.regs;
-		regs->gpr[3] = ret = sigctx.signal;
-		/* Get the siginfo   */
-		get_user(regs->gpr[4], (unsigned long *)&rt_sf->pinfo);
-		/* Get the ucontext */
-		get_user(regs->gpr[5], (unsigned long *)&rt_sf->puc);
-		regs->gpr[6] = (unsigned long) rt_sf;
-
-		regs->link = (unsigned long) &sr->tramp;
-		regs->nip = sigctx.handler;
-		if (get_user(prevsp, &sr->gp_regs[PT_R1])
-		    || put_user(prevsp, (unsigned long *) regs->gpr[1]))
-			goto badframe;
-	}
-	return ret;
+	if (restore_sigcontext(regs, NULL, &uc->uc_mcontext))
+		goto badframe;
+
+	if (__copy_from_user(&st, &uc->uc_stack, sizeof(st)))
+		goto badframe;
+
+	/* This function sets back the stack flags into
+	   the current task structure.  */
+	sys_sigaltstack(&st, NULL, 0, 0, 0, 0, regs);
+
+	return regs->result;
 
 badframe:
 	do_exit(SIGSEGV);
 }
 
 static void
-setup_rt_frame(struct pt_regs *regs, struct sigregs *frame,
-	       signed long newsp)
+setup_rt_frame(int signr, struct k_sigaction *ka, siginfo_t *info,
+		sigset_t *set, struct pt_regs *regs)
 {
-	struct rt_sigframe *rt_sf = (struct rt_sigframe *) newsp;
 	/* Handler is *really* a pointer to the function descriptor for
 	 * the signal routine.  The first entry in the function
 	 * descriptor is the entry address of signal and the second
 	 * entry is the TOC value we need to use.
 	 */
-        struct funct_descr_entry {
-                     unsigned long entry;
-                     unsigned long toc;
-	};
-  
-	struct funct_descr_entry * funct_desc_ptr;
-	unsigned long temp_ptr;
+	func_descr_t *funct_desc_ptr;
+	struct rt_sigframe *frame;
+	unsigned long newsp;
+	int err = 0;
 
-	/* Set up preamble frame */
-	if (verify_area(VERIFY_WRITE, frame, sizeof(*frame)))
-		goto badframe;
-	if (regs->msr & MSR_FP)
-		giveup_fpu(current);
-	if (__copy_to_user(&frame->gp_regs, regs, GP_REGS_SIZE)
-	    || __copy_to_user(&frame->fp_regs, current->thread.fpr,
-			      ELF_NFPREG * sizeof(double))
-	    || __put_user(0x38000000UL + __NR_rt_sigreturn, &frame->tramp[0])	/* li r0, __NR_rt_sigreturn */
-	    || __put_user(0x44000002UL, &frame->tramp[1]))	/* sc */
-		goto badframe;
-	flush_icache_range((unsigned long) &frame->tramp[0],
-			   (unsigned long) &frame->tramp[2]);
+	frame = get_sigframe(ka, regs, sizeof(*frame));
 
-	/* Retrieve rt_sigframe from stack and
-	   set up registers for signal handler
-	*/
-	newsp -= __SIGNAL_FRAMESIZE;
-
-        if ( get_user(temp_ptr, &rt_sf->uc.uc_mcontext.handler)) {
-		goto badframe;
-	}
-
-        funct_desc_ptr = ( struct funct_descr_entry *) temp_ptr;
-        
-	if (put_user(regs->gpr[1], (unsigned long *)newsp)
-	    || get_user(regs->nip, &funct_desc_ptr->entry)
-            || get_user(regs->gpr[2], &funct_desc_ptr->toc)
-	    || get_user(regs->gpr[3], &rt_sf->uc.uc_mcontext.signal)
-	    || get_user(regs->gpr[4], (unsigned long *)&rt_sf->pinfo)
-	    || get_user(regs->gpr[5], (unsigned long *)&rt_sf->puc))
-		goto badframe;
+	if (verify_area(VERIFY_WRITE, frame, sizeof(*frame)))
+		goto give_sigsegv;
 
+	err |= __put_user(&frame->info, &frame->pinfo);
+	err |= __put_user(&frame->uc, &frame->puc);
+	err |= copy_siginfo_to_user(&frame->info, info);
+	if (err)
+		goto give_sigsegv;
+
+	/* Create the ucontext.  */
+	err |= __put_user(0, &frame->uc.uc_flags);
+	err |= __put_user(0, &frame->uc.uc_link);
+	err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
+	err |= __put_user(sas_ss_flags(regs->gpr[1]),
+			  &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, signr, NULL,
+				(unsigned long)ka->sa.sa_handler);
+	err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+	if (err)
+		goto give_sigsegv;
+
+	/* Set up to return from userspace. */
+	err |= setup_trampoline(__NR_rt_sigreturn, &frame->tramp[0]);
+	if (err)
+		goto give_sigsegv;
+
+	funct_desc_ptr = (func_descr_t *) ka->sa.sa_handler;
+
+	/* Allocate a dummy caller frame for the signal handler. */
+	newsp = (unsigned long)frame - __SIGNAL_FRAMESIZE;
+	err |= put_user(0, (unsigned long *)newsp);
+
+	/* Set up "regs" so we "return" to the signal handler. */
+	err |= get_user(regs->nip, &funct_desc_ptr->entry);
+	regs->link = (unsigned long) &frame->tramp[0];
 	regs->gpr[1] = newsp;
-	regs->gpr[6] = (unsigned long) rt_sf;
-	regs->link = (unsigned long) frame->tramp;
+	err |= get_user(regs->gpr[2], &funct_desc_ptr->toc);
+	regs->gpr[3] = signr;
+	err |= get_user(regs->gpr[4], (unsigned long *)&frame->pinfo);
+	err |= get_user(regs->gpr[5], (unsigned long *)&frame->puc);
+	regs->gpr[6] = (unsigned long) frame;
+	if (err)
+		goto give_sigsegv;
 
-	
 	return;
 
-badframe:
+give_sigsegv:
 #if DEBUG_SIG
-	printk("badframe in setup_rt_frame, regs=%p frame=%p newsp=%lx\n",
-	       regs, frame, newsp);
+	printk("badframe in setup_rt_frame, regs=%p frame=%p, newsp=0x%lx\n",
+		regs, frame, newsp);
 #endif
 	do_exit(SIGSEGV);
 }
@@ -403,131 +433,79 @@
 /*
  * Do a signal return; undo the signal stack.
  */
-long sys_sigreturn(unsigned long r3, unsigned long r4, unsigned long r5,
-		   unsigned long r6, unsigned long r7, unsigned long r8,
-		   struct pt_regs *regs)
-{
-	struct sigcontext_struct *sc, sigctx;
-	struct sigregs *sr;
-	long ret;
-	elf_gregset_t saved_regs;  /* an array of ELF_NGREG unsigned longs */
+asmlinkage long
+sys_sigreturn(unsigned long r3, unsigned long r4, unsigned long r5,
+	      unsigned long r6, unsigned long r7, unsigned long r8,
+	      struct pt_regs *regs)
+{
+	struct sigcontext *sc = (struct sigcontext *)regs->gpr[1];
 	sigset_t set;
-	unsigned long prevsp;
 
-        sc = (struct sigcontext_struct *)(regs->gpr[1] + __SIGNAL_FRAMESIZE);
-	if (copy_from_user(&sigctx, sc, sizeof(sigctx)))
+	if (verify_area(VERIFY_READ, sc, sizeof(*sc)))
+		goto badframe;
+
+	if (restore_sigcontext(regs, &set, sc))
 		goto badframe;
 
-	set.sig[0] = sigctx.oldmask;
-#if _NSIG_WORDS > 1
-	set.sig[1] = sigctx._unused[3];
-#endif
 	sigdelsetmask(&set, ~_BLOCKABLE);
 	spin_lock_irq(&current->sigmask_lock);
 	current->blocked = set;
 	recalc_sigpending(current);
 	spin_unlock_irq(&current->sigmask_lock);
 
-	sc++;			/* Look at next sigcontext */
-	if (sc == (struct sigcontext_struct *)(sigctx.regs)) {
-		/* Last stacked signal - restore registers */
-		sr = (struct sigregs *) sigctx.regs;
-		if (regs->msr & MSR_FP )
-			giveup_fpu(current);
-		if (copy_from_user(saved_regs, &sr->gp_regs,
-				   sizeof(sr->gp_regs)))
-			goto badframe;
-		saved_regs[PT_MSR] = (regs->msr & ~MSR_USERCHANGE)
-			| (saved_regs[PT_MSR] & MSR_USERCHANGE);
-		saved_regs[PT_SOFTE] = regs->softe;
-		memcpy(regs, saved_regs, GP_REGS_SIZE);
-
-		if (copy_from_user(current->thread.fpr, &sr->fp_regs,
-				   sizeof(sr->fp_regs)))
-			goto badframe;
-
-		ret = regs->result;
-
-	} else {
-		/* More signals to go */
-		regs->gpr[1] = (unsigned long)sc - __SIGNAL_FRAMESIZE;
-		if (copy_from_user(&sigctx, sc, sizeof(sigctx)))
-			goto badframe;
-		sr = (struct sigregs *) sigctx.regs;
-		regs->gpr[3] = ret = sigctx.signal;
-		regs->gpr[4] = (unsigned long) sc;
-		regs->link = (unsigned long) &sr->tramp;
-		regs->nip = sigctx.handler;
-
-		if (get_user(prevsp, &sr->gp_regs[PT_R1])
-		    || put_user(prevsp, (unsigned long *) regs->gpr[1]))
-			goto badframe;
-	}
-	return ret;
+	return regs->result;
 
 badframe:
 	do_exit(SIGSEGV);
 }	
 
-/*
- * Set up a signal frame.
- */
+
 static void
-setup_frame(struct pt_regs *regs, struct sigregs *frame,
-            unsigned long newsp)
+setup_frame(int signr, struct k_sigaction *ka, sigset_t *set,
+	    struct pt_regs *regs)
 {
-
 	/* Handler is *really* a pointer to the function descriptor for
 	 * the signal routine.  The first entry in the function
 	 * descriptor is the entry address of signal and the second
 	 * entry is the TOC value we need to use.
 	 */
-	struct funct_descr_entry {
-		unsigned long entry;
-		unsigned long toc;
-	};
-  
-	struct funct_descr_entry * funct_desc_ptr;
-	unsigned long temp_ptr;
+	func_descr_t *funct_desc_ptr;
+	struct sigframe *frame;
+	unsigned long newsp;
+	int err = 0;
+
+	frame = get_sigframe(ka, regs, sizeof(*frame));
 
-	struct sigcontext_struct *sc = (struct sigcontext_struct *) newsp;
-  
 	if (verify_area(VERIFY_WRITE, frame, sizeof(*frame)))
 		goto badframe;
-	if (regs->msr & MSR_FP)
-		giveup_fpu(current);
-	if (__copy_to_user(&frame->gp_regs, regs, GP_REGS_SIZE)
-	    || __copy_to_user(&frame->fp_regs, current->thread.fpr,
-			      ELF_NFPREG * sizeof(double))
-	    || __put_user(0x38000000UL + __NR_sigreturn, &frame->tramp[0])    /* li r0, __NR_sigreturn */
-	    || __put_user(0x44000002UL, &frame->tramp[1]))   /* sc */
-		goto badframe;
-	flush_icache_range((unsigned long) &frame->tramp[0],
-			   (unsigned long) &frame->tramp[2]);
 
-	newsp -= __SIGNAL_FRAMESIZE;
-	if ( get_user(temp_ptr, &sc->handler))
-		goto badframe;
-  
-	funct_desc_ptr = ( struct funct_descr_entry *) temp_ptr;
+	err |= setup_sigcontext(&frame->sc, regs, signr, set,
+				(unsigned long)ka->sa.sa_handler);
 
-	if (put_user(regs->gpr[1], (unsigned long *)newsp)
-	    || get_user(regs->nip, & funct_desc_ptr ->entry)
-	    || get_user(regs->gpr[2],& funct_desc_ptr->toc)
-	    || get_user(regs->gpr[3], &sc->signal))
+	/* Set up to return from userspace. */
+	err |= setup_trampoline(__NR_sigreturn, &frame->tramp[0]);
+	if (err)
 		goto badframe;
-	regs->gpr[1] = newsp;
-	regs->gpr[4] = (unsigned long) sc;
-	regs->link = (unsigned long) frame->tramp;
 
+	funct_desc_ptr = (func_descr_t *) ka->sa.sa_handler;
 
-	PPCDBG(PPCDBG_SIGNAL, "setup_frame - returning - regs->gpr[1]=%lx, regs->gpr[4]=%lx, regs->link=%lx \n",
-	       regs->gpr[1], regs->gpr[4], regs->link);
+	/* Allocate a dummy caller frame for the signal handler. */
+	newsp = (unsigned long)frame - __SIGNAL_FRAMESIZE;
+	err |= put_user(0, (unsigned long *)newsp);
+
+	/* Set up "regs" so we "return" to the signal handler. */
+	err |= get_user(regs->nip, &funct_desc_ptr->entry);
+	regs->link = (unsigned long) &frame->tramp[0];
+	regs->gpr[1] = newsp;
+	err |= get_user(regs->gpr[2], &funct_desc_ptr->toc);
+	regs->gpr[3] = signr;
+	regs->gpr[4] = (unsigned long) &frame->sc;
+	if (err)
+		goto badframe;
 
 	return;
 
- badframe:
-	PPCDBG(PPCDBG_SIGNAL, "setup_frame - badframe in setup_frame, regs=%p frame=%p newsp=%lx\n", regs, frame, newsp);  PPCDBG_ENTER_DEBUGGER();
+badframe:
 #if DEBUG_SIG
 	printk("badframe in setup_frame, regs=%p frame=%p newsp=%lx\n",
 	       regs, frame, newsp);
@@ -540,61 +518,13 @@
  */
 static void
 handle_signal(unsigned long sig, struct k_sigaction *ka,
-	      siginfo_t *info, sigset_t *oldset, struct pt_regs * regs,
-	      unsigned long *newspp, unsigned long frame)
+	      siginfo_t *info, sigset_t *oldset, struct pt_regs *regs)
 {
-	struct sigcontext_struct *sc;
-        struct rt_sigframe *rt_sf;
-
-	if (regs->trap == 0x0C00 /* System Call! */
-	    && ((int)regs->result == -ERESTARTNOHAND ||
-		((int)regs->result == -ERESTARTSYS &&
-		 !(ka->sa.sa_flags & SA_RESTART))))
-		regs->result = -EINTR;
-        /* Set up Signal Frame */
-     
-	if (ka->sa.sa_flags & SA_SIGINFO) {
-		/* Put a Real Time Context onto stack */
-		*newspp -= sizeof(*rt_sf);
-		rt_sf = (struct rt_sigframe *) *newspp;
-		if (verify_area(VERIFY_WRITE, rt_sf, sizeof(*rt_sf)))
-			goto badframe;
-                
-
-		if (__put_user((unsigned long) ka->sa.sa_handler, &rt_sf->uc.uc_mcontext.handler)
-		    || __put_user(&rt_sf->info, &rt_sf->pinfo)
-		    || __put_user(&rt_sf->uc, &rt_sf->puc)
-		    /* Put the siginfo */
-		    || __copy_to_user(&rt_sf->info, info, sizeof(*info))
-		    /* Create the ucontext */
-		    || __put_user(0, &rt_sf->uc.uc_flags)
-		    || __put_user(0, &rt_sf->uc.uc_link)
-		    || __put_user(current->sas_ss_sp, &rt_sf->uc.uc_stack.ss_sp)
-		    || __put_user(sas_ss_flags(regs->gpr[1]), 
-				  &rt_sf->uc.uc_stack.ss_flags)
-		    || __put_user(current->sas_ss_size, &rt_sf->uc.uc_stack.ss_size)
-		    || __copy_to_user(&rt_sf->uc.uc_sigmask, oldset, sizeof(*oldset))
-		    /* mcontext.regs points to preamble register frame */
-		    || __put_user((struct pt_regs *)frame, &rt_sf->uc.uc_mcontext.regs)
-		    || __put_user(sig, &rt_sf->uc.uc_mcontext.signal))
-			goto badframe;
-               
-	} else {
-	        /* Put another sigcontext on the stack */
-                *newspp -= sizeof(*sc);
-        	sc = (struct sigcontext_struct *) *newspp;
-        	if (verify_area(VERIFY_WRITE, sc, sizeof(*sc)))
-	        	goto badframe;
-
-        	if (__put_user((unsigned long) ka->sa.sa_handler, &sc->handler)
-	           || __put_user(oldset->sig[0], &sc->oldmask)
-#if _NSIG_WORDS > 1
-	           || __put_user(oldset->sig[1], &sc->_unused[3])
-#endif
-	           || __put_user((struct pt_regs *)frame, &sc->regs)
-	           || __put_user(sig, &sc->signal))
-	        	goto badframe;
-	}
+	/* Set up Signal Frame */
+	if (ka->sa.sa_flags & SA_SIGINFO)
+		setup_rt_frame(sig, ka, info, oldset, regs);
+	else
+		setup_frame(sig, ka, oldset, regs);
 
 	if (ka->sa.sa_flags & SA_ONESHOT)
 		ka->sa.sa_handler = SIG_DFL;
@@ -606,49 +536,47 @@
 		recalc_sigpending(current);
 		spin_unlock_irq(&current->sigmask_lock);
 	}
-	return;
-
-badframe:
-#if DEBUG_SIG
-	printk("badframe in handle_signal, regs=%p frame=%lx newsp=%lx\n",
-	       regs, frame, *newspp);
-	printk("sc=%p sig=%d ka=%p info=%p oldset=%p\n", sc, sig, ka, info, oldset);
-#endif
-	do_exit(SIGSEGV);
 }
 
-/*
- * 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.
- */
-extern int do_signal32(sigset_t *oldset, struct pt_regs *regs);
-int do_signal(sigset_t *oldset, struct pt_regs *regs)
+static inline void
+syscall_restart(struct pt_regs *regs, struct k_sigaction *ka)
 {
-	siginfo_t info;
-	struct k_sigaction *ka;
-	unsigned long frame, newsp;
-
-	/*
-	 * If the current thread is 32 bit - invoke the
-	 * 32 bit signal handling code
-	 */
-	if (current->thread.flags & PPC_FLAG_32BIT)
-		return do_signal32(oldset, regs);
-
-        if (!oldset)
-		oldset = &current->blocked;
+	switch ((int)regs->result) {
+		case -ERESTARTNOHAND:
+			/* ERESTARTNOHAND means that the syscall should only
+			   be restarted if there was no handler for the signal,
+			   and since we only get here if there is a handler,
+			   we dont restart */
+			regs->result = -EINTR;
+			break;
 
-	newsp = frame = 0;
+		case -ERESTARTSYS:
+			/* ERESTARTSYS means to restart the syscall if there is
+			   no handler or the handler was registered with SA_RESTART */
+			if (!(ka->sa.sa_flags & SA_RESTART)) {
+				regs->result = -EINTR;
+				break;
+			}
+		/* fallthrough */
+		case -ERESTARTNOINTR:
+			/* ERESTARTNOINTR means that the syscall should be
+			   called again after the signal handler returns */
+			regs->gpr[3] = regs->orig_gpr3;
+			regs->nip -= 4;
+			regs->result = 0;
+	}
+}
 
+static int
+get_signal_to_deliver(siginfo_t *info, struct pt_regs *regs)
+{
 	for (;;) {
 		unsigned long signr;
+		struct k_sigaction *ka;
 
-                PPCDBG(PPCDBG_SIGNAL, "do_signal - (pre) dequeueing signal - pid=%ld current=%lx comm=%s \n", current->pid, current, current->comm);
 		spin_lock_irq(&current->sigmask_lock);
-		signr = dequeue_signal(&current->blocked, &info);
+		signr = dequeue_signal(&current->blocked, info);
 		spin_unlock_irq(&current->sigmask_lock);
-                PPCDBG(PPCDBG_SIGNAL, "do_signal - (aft) dequeueing signal - signal=%lx - pid=%ld current=%lx comm=%s \n", signr, current->pid, current, current->comm);
 
 		if (!signr)
 			break;
@@ -661,7 +589,8 @@
 			schedule();
 
 			/* We're back.  Did the debugger cancel the sig?  */
-			if (!(signr = current->exit_code))
+			signr = current->exit_code;
+			if (signr == 0)
 				continue;
 			current->exit_code = 0;
 
@@ -670,28 +599,24 @@
 				continue;
 
 			/* Update the siginfo structure.  Is this good?  */
-			if (signr != info.si_signo) {
-				info.si_signo = signr;
-				info.si_errno = 0;
-				info.si_code = SI_USER;
-				info.si_pid = current->p_pptr->pid;
-				info.si_uid = current->p_pptr->uid;
+			if (signr != info->si_signo) {
+				info->si_signo = signr;
+				info->si_errno = 0;
+				info->si_code = SI_USER;
+				info->si_pid = current->p_pptr->pid;
+				info->si_uid = current->p_pptr->uid;
 			}
 
 			/* If the (new) signal is now blocked, requeue it.  */
 			if (sigismember(&current->blocked, signr)) {
-				send_sig_info(signr, &info, current);
+				send_sig_info(signr, info, current);
 				continue;
 			}
 		}
 
 		ka = &current->sig->action[signr-1];
 
-  
-                PPCDBG(PPCDBG_SIGNAL, "do_signal - ka=%p, action handler=%lx \n", ka, ka->sa.sa_handler);
-
 		if (ka->sa.sa_handler == SIG_IGN) {
-                        PPCDBG(PPCDBG_SIGNAL, "do_signal - into SIG_IGN logic \n");
 			if (signr != SIGCHLD)
 				continue;
 			/* Check for SIGCHLD: it's special.  */
@@ -702,7 +627,6 @@
 
 		if (ka->sa.sa_handler == SIG_DFL) {
 			int exit_code = signr;
-                        PPCDBG(PPCDBG_SIGNAL, "do_signal - into SIG_DFL logic \n");
 
 			/* Init gets no signals it doesn't want.  */
 			if (current->pid == 1)
@@ -736,48 +660,60 @@
 				/* FALLTHRU */
 
 			default:
-				sig_exit(signr, exit_code, &info);
+				sig_exit(signr, exit_code, info);
 				/* NOTREACHED */
 			}
 		}
+		return signr;
+	}
+	return 0;
+}
 
-		if ( (ka->sa.sa_flags & SA_ONSTACK)
-		     && (! on_sig_stack(regs->gpr[1])))
-			newsp = (current->sas_ss_sp + current->sas_ss_size);
-		else
-			newsp = regs->gpr[1];
-		newsp = frame = newsp - sizeof(struct sigregs);
+/*
+ * 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.
+ */
+extern int do_signal32(sigset_t *oldset, struct pt_regs *regs);
+
+int
+do_signal(sigset_t *oldset, struct pt_regs *regs)
+{
+	siginfo_t info;
+	int signr;
+
+	/*
+	 * If the current thread is 32 bit - invoke the
+	 * 32 bit signal handling code
+	 */
+	if (current->thread.flags & PPC_FLAG_32BIT)
+		return do_signal32(oldset, regs);
+
+        if (!oldset)
+		oldset = &current->blocked;
+
+	signr = get_signal_to_deliver(&info, regs);
+	if (signr > 0) {
+		struct k_sigaction *ka = &current->sig->action[signr-1];
 
 		/* Whee!  Actually deliver the signal.  */
-  
-                PPCDBG(PPCDBG_SIGNAL, "do_signal - GOING TO RUN SIGNAL HANDLER - pid=%ld current=%lx comm=%s \n", current->pid, current, current->comm);
-		handle_signal(signr, ka, &info, oldset, regs, &newsp, frame);
-                PPCDBG(PPCDBG_SIGNAL, "do_signal - after running signal handler - pid=%ld current=%lx comm=%s \n", current->pid, current, current->comm);
-                break;
+		if (regs->trap == 0x0C00)
+			syscall_restart(regs, ka);
+		handle_signal(signr, ka, &info, oldset, regs);
+		return 1;
 	}
 
 	if (regs->trap == 0x0C00 /* System Call! */ &&
 	    ((int)regs->result == -ERESTARTNOHAND ||
 	     (int)regs->result == -ERESTARTSYS ||
 	     (int)regs->result == -ERESTARTNOINTR)) {
-                PPCDBG(PPCDBG_SIGNAL, "do_signal - going to back up & retry system call \n");
 		regs->gpr[3] = regs->orig_gpr3;
 		regs->nip -= 4;		/* Back up & retry system call */
 		regs->result = 0;
 	}
 
-	if (newsp == frame)
-          {
-             PPCDBG(PPCDBG_SIGNAL, "do_signal - returning w/ no signal delivered \n");
-             return 0;		/* no signals delivered */
-           }
-  
-     
-
-        if (ka->sa.sa_flags & SA_SIGINFO)
-             setup_rt_frame(regs, (struct sigregs *) frame, newsp);
-        else        
-	    setup_frame(regs, (struct sigregs *) frame, newsp);
-        PPCDBG(PPCDBG_SIGNAL, "do_signal - returning a signal was delivered \n");
-	return 1;
+	return 0;
 }
+
+
+