powerpc: merge ppc signal.c and ppc64 signal32.c

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>

1 files changed, 1269 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
new file mode 100644
index 000000000000..e53127ec373d
--- /dev/null
+++ b/arch/powerpc/kernel/signal_32.c
@@ -0,0 +1,1269 @@
+/*
+ * Signal handling for 32bit PPC and 32bit tasks on 64bit PPC
+ *
+ *  PowerPC version
+ *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ * Copyright (C) 2001 IBM
+ * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
+ * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
+ *
+ *  Derived from "arch/i386/kernel/signal.c"
+ *    Copyright (C) 1991, 1992 Linus Torvalds
+ *    1997-11-28  Modified for POSIX.1b signals by Richard Henderson
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; either version
+ *  2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/config.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/errno.h>
+#include <linux/elf.h>
+#ifdef CONFIG_PPC64
+#include <linux/syscalls.h>
+#include <linux/compat.h>
+#include <linux/ptrace.h>
+#else
+#include <linux/wait.h>
+#include <linux/ptrace.h>
+#include <linux/unistd.h>
+#include <linux/stddef.h>
+#include <linux/tty.h>
+#include <linux/binfmts.h>
+#include <linux/suspend.h>
+#endif
+
+#include <asm/uaccess.h>
+#include <asm/cacheflush.h>
+#ifdef CONFIG_PPC64
+#include <asm/ppc32.h>
+#include <asm/ppcdebug.h>
+#include <asm/unistd.h>
+#include <asm/vdso.h>
+#else
+#include <asm/ucontext.h>
+#include <asm/pgtable.h>
+#endif
+
+#undef DEBUG_SIG
+
+#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
+
+#ifdef CONFIG_PPC64
+#define do_signal	do_signal32
+#define sys_sigsuspend	sys32_sigsuspend
+#define sys_rt_sigsuspend	sys32_rt_sigsuspend
+#define sys_rt_sigreturn	sys32_rt_sigreturn
+#define sys_sigaction	sys32_sigaction
+#define sys_swapcontext	sys32_swapcontext
+#define sys_sigreturn	sys32_sigreturn
+
+#define old_sigaction	old_sigaction32
+#define sigcontext	sigcontext32
+#define mcontext	mcontext32
+#define ucontext	ucontext32
+
+/*
+ * Returning 0 means we return to userspace via
+ * ret_from_except and thus restore all user
+ * registers from *regs.  This is what we need
+ * to do when a signal has been delivered.
+ */
+#define sigreturn_exit(regs)	return 0
+
+#define GP_REGS_SIZE	min(sizeof(elf_gregset_t32), sizeof(struct pt_regs32))
+#undef __SIGNAL_FRAMESIZE
+#define __SIGNAL_FRAMESIZE	__SIGNAL_FRAMESIZE32
+#undef ELF_NVRREG
+#define ELF_NVRREG	ELF_NVRREG32
+
+/*
+ * Functions for flipping sigsets (thanks to brain dead generic
+ * implementation that makes things simple for little endian only)
+ */
+static inline int put_sigset_t(compat_sigset_t __user *uset, sigset_t *set)
+{
+	compat_sigset_t	cset;
+
+	switch (_NSIG_WORDS) {
+	case 4: cset.sig[5] = set->sig[3] & 0xffffffffull;
+		cset.sig[7] = set->sig[3] >> 32;
+	case 3: cset.sig[4] = set->sig[2] & 0xffffffffull;
+		cset.sig[5] = set->sig[2] >> 32;
+	case 2: cset.sig[2] = set->sig[1] & 0xffffffffull;
+		cset.sig[3] = set->sig[1] >> 32;
+	case 1: cset.sig[0] = set->sig[0] & 0xffffffffull;
+		cset.sig[1] = set->sig[0] >> 32;
+	}
+	return copy_to_user(uset, &cset, sizeof(*uset));
+}
+
+static inline int get_sigset_t(sigset_t *set, compat_sigset_t __user *uset)
+{
+	compat_sigset_t s32;
+
+	if (copy_from_user(&s32, uset, sizeof(*uset)))
+		return -EFAULT;
+
+	/*
+	 * Swap the 2 words of the 64-bit sigset_t (they are stored
+	 * in the "wrong" endian in 32-bit user storage).
+	 */
+	switch (_NSIG_WORDS) {
+	case 4: set->sig[3] = s32.sig[6] | (((long)s32.sig[7]) << 32);
+	case 3: set->sig[2] = s32.sig[4] | (((long)s32.sig[5]) << 32);
+	case 2: set->sig[1] = s32.sig[2] | (((long)s32.sig[3]) << 32);
+	case 1: set->sig[0] = s32.sig[0] | (((long)s32.sig[1]) << 32);
+	}
+	return 0;
+}
+
+static inline int get_old_sigaction(struct k_sigaction *new_ka,
+		struct old_sigaction __user *act)
+{
+	compat_old_sigset_t mask;
+	compat_uptr_t handler, restorer;
+
+	if (get_user(handler, &act->sa_handler) ||
+	    __get_user(restorer, &act->sa_restorer) ||
+	    __get_user(new_ka->sa.sa_flags, &act->sa_flags) ||
+	    __get_user(mask, &act->sa_mask))
+		return -EFAULT;
+	new_ka->sa.sa_handler = compat_ptr(handler);
+	new_ka->sa.sa_restorer = compat_ptr(restorer);
+	siginitset(&new_ka->sa.sa_mask, mask);
+	return 0;
+}
+
+static inline compat_uptr_t to_user_ptr(void *kp)
+{
+	return (compat_uptr_t)(u64)kp;
+}
+
+#define from_user_ptr(p)	compat_ptr(p)
+
+static inline int save_general_regs(struct pt_regs *regs,
+		struct mcontext __user *frame)
+{
+	elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
+	int i;
+
+	for (i = 0; i <= PT_RESULT; i ++)
+		if (__put_user((unsigned int)gregs[i], &frame->mc_gregs[i]))
+			return -EFAULT;
+	return 0;
+}
+
+static inline int restore_general_regs(struct pt_regs *regs,
+		struct mcontext __user *sr)
+{
+	elf_greg_t64 *gregs = (elf_greg_t64 *)regs;
+	int i;
+
+	for (i = 0; i <= PT_RESULT; i++) {
+		if ((i == PT_MSR) || (i == PT_SOFTE))
+			continue;
+		if (__get_user(gregs[i], &sr->mc_gregs[i]))
+			return -EFAULT;
+	}
+	return 0;
+}
+
+#else /* CONFIG_PPC64 */
+
+extern void sigreturn_exit(struct pt_regs *);
+
+#define GP_REGS_SIZE	min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
+
+static inline int put_sigset_t(sigset_t __user *uset, sigset_t *set)
+{
+	return copy_to_user(uset, set, sizeof(*uset));
+}
+
+static inline int get_sigset_t(sigset_t *set, sigset_t __user *uset)
+{
+	return copy_from_user(set, uset, sizeof(*uset));
+}
+
+static inline int get_old_sigaction(struct k_sigaction *new_ka,
+		struct old_sigaction __user *act)
+{
+	old_sigset_t mask;
+
+	if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
+			__get_user(new_ka->sa.sa_handler, &act->sa_handler) ||
+			__get_user(new_ka->sa.sa_restorer, &act->sa_restorer))
+		return -EFAULT;
+	__get_user(new_ka->sa.sa_flags, &act->sa_flags);
+	__get_user(mask, &act->sa_mask);
+	siginitset(&new_ka->sa.sa_mask, mask);
+	return 0;
+}
+
+#define to_user_ptr(p)		(p)
+#define from_user_ptr(p)	(p)
+
+static inline int save_general_regs(struct pt_regs *regs,
+		struct mcontext __user *frame)
+{
+	return __copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE);
+}
+
+static inline int restore_general_regs(struct pt_regs *regs,
+		struct mcontext __user *sr)
+{
+	/* copy up to but not including MSR */
+	if (__copy_from_user(regs, &sr->mc_gregs,
+				PT_MSR * sizeof(elf_greg_t)))
+		return -EFAULT;
+	/* copy from orig_r3 (the word after the MSR) up to the end */
+	if (__copy_from_user(&regs->orig_gpr3, &sr->mc_gregs[PT_ORIG_R3],
+				GP_REGS_SIZE - PT_ORIG_R3 * sizeof(elf_greg_t)))
+		return -EFAULT;
+	return 0;
+}
+
+#endif /* CONFIG_PPC64 */
+
+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,
+	       struct pt_regs *regs)
+{
+	sigset_t saveset;
+
+	mask &= _BLOCKABLE;
+	spin_lock_irq(&current->sighand->siglock);
+	saveset = current->blocked;
+	siginitset(&current->blocked, mask);
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
+
+	regs->result = -EINTR;
+	regs->gpr[3] = EINTR;
+	regs->ccr |= 0x10000000;
+	while (1) {
+		current->state = TASK_INTERRUPTIBLE;
+		schedule();
+		if (do_signal(&saveset, regs))
+			sigreturn_exit(regs);
+	}
+}
+
+long sys_rt_sigsuspend(
+#ifdef CONFIG_PPC64
+		compat_sigset_t __user *unewset,
+#else
+		sigset_t __user *unewset,
+#endif
+		size_t sigsetsize, int p3, int p4,
+		int p6, int p7, struct pt_regs *regs)
+{
+	sigset_t saveset, newset;
+
+	/* XXX: Don't preclude handling different sized sigset_t's.  */
+	if (sigsetsize != sizeof(sigset_t))
+		return -EINVAL;
+
+	if (get_sigset_t(&newset, unewset))
+		return -EFAULT;
+	sigdelsetmask(&newset, ~_BLOCKABLE);
+
+	spin_lock_irq(&current->sighand->siglock);
+	saveset = current->blocked;
+	current->blocked = newset;
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
+
+	regs->result = -EINTR;
+	regs->gpr[3] = EINTR;
+	regs->ccr |= 0x10000000;
+	while (1) {
+		current->state = TASK_INTERRUPTIBLE;
+		schedule();
+		if (do_signal(&saveset, regs))
+			sigreturn_exit(regs);
+	}
+}
+
+#ifdef CONFIG_PPC32
+long sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss, int r5,
+		int r6, int r7, int r8, struct pt_regs *regs)
+{
+	return do_sigaltstack(uss, uoss, regs->gpr[1]);
+}
+#endif
+
+long sys_sigaction(int sig, struct old_sigaction __user *act,
+		struct old_sigaction __user *oact)
+{
+	struct k_sigaction new_ka, old_ka;
+	int ret;
+
+#ifdef CONFIG_PPC64
+	if (sig < 0)
+		sig = -sig;
+#endif
+
+	if (act) {
+		if (get_old_sigaction(&new_ka, act))
+			return -EFAULT;
+	}
+
+	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
+	if (!ret && oact) {
+		if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
+		    __put_user(to_user_ptr(old_ka.sa.sa_handler),
+			    &oact->sa_handler) ||
+		    __put_user(to_user_ptr(old_ka.sa.sa_restorer),
+			    &oact->sa_restorer) ||
+		    __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
+		    __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
+			return -EFAULT;
+	}
+
+	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
+ *	a sigcontext struct
+ *	a gap of __SIGNAL_FRAMESIZE bytes
+ *
+ * Each of these things must be a multiple of 16 bytes in size.
+ *
+ */
+struct sigregs {
+	struct mcontext	mctx;		/* all the register values */
+	/*
+	 * Programs using the rs6000/xcoff abi can save up to 19 gp
+	 * regs and 18 fp regs below sp before decrementing it.
+	 */
+	int			abigap[56];
+};
+
+/* We use the mc_pad field for the signal return trampoline. */
+#define tramp	mc_pad
+
+/*
+ *  When we have rt signals to deliver, we set up on the
+ *  user stack, going down from the original stack pointer:
+ *	one rt_sigframe struct (siginfo + ucontext + ABI gap)
+ *	a gap of __SIGNAL_FRAMESIZE+16 bytes
+ *  (the +16 is to get the siginfo and ucontext in the same
+ *  positions as in older kernels).
+ *
+ *  Each of these things must be a multiple of 16 bytes in size.
+ *
+ */
+struct rt_sigframe {
+#ifdef CONFIG_PPC64
+	compat_siginfo_t info;
+#else
+	struct siginfo info;
+#endif
+	struct ucontext	uc;
+	/*
+	 * Programs using the rs6000/xcoff abi can save up to 19 gp
+	 * regs and 18 fp regs below sp before decrementing it.
+	 */
+	int			abigap[56];
+};
+
+/*
+ * Save the current user registers on the user stack.
+ * We only save the altivec/spe registers if the process has used
+ * altivec/spe instructions at some point.
+ */
+static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
+		int sigret)
+{
+#ifdef CONFIG_PPC32
+	CHECK_FULL_REGS(regs);
+#endif
+	/* Make sure floating point registers are stored in regs */
+	flush_fp_to_thread(current);
+
+	/* save general and floating-point registers */
+	if (save_general_regs(regs, frame) ||
+	    __copy_to_user(&frame->mc_fregs, current->thread.fpr,
+		    ELF_NFPREG * sizeof(double)))
+		return 1;
+
+	current->thread.fpscr = 0;	/* turn off all fp exceptions */
+
+#ifdef CONFIG_ALTIVEC
+	/* save altivec registers */
+	if (current->thread.used_vr) {
+		flush_altivec_to_thread(current);
+		if (__copy_to_user(&frame->mc_vregs, current->thread.vr,
+				   ELF_NVRREG * sizeof(vector128)))
+			return 1;
+		/* set MSR_VEC in the saved MSR value to indicate that
+		   frame->mc_vregs contains valid data */
+		if (__put_user(regs->msr | MSR_VEC, &frame->mc_gregs[PT_MSR]))
+			return 1;
+	}
+	/* else assert((regs->msr & MSR_VEC) == 0) */
+
+	/* We always copy to/from vrsave, it's 0 if we don't have or don't
+	 * use altivec. Since VSCR only contains 32 bits saved in the least
+	 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
+	 * most significant bits of that same vector. --BenH
+	 */
+	if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32]))
+		return 1;
+#endif /* CONFIG_ALTIVEC */
+
+#ifdef CONFIG_SPE
+	/* save spe registers */
+	if (current->thread.used_spe) {
+		flush_spe_to_thread(current);
+		if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
+				   ELF_NEVRREG * sizeof(u32)))
+			return 1;
+		/* set MSR_SPE in the saved MSR value to indicate that
+		   frame->mc_vregs contains valid data */
+		if (__put_user(regs->msr | MSR_SPE, &frame->mc_gregs[PT_MSR]))
+			return 1;
+	}
+	/* else assert((regs->msr & MSR_SPE) == 0) */
+
+	/* We always copy to/from spefscr */
+	if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
+		return 1;
+#endif /* CONFIG_SPE */
+
+	if (sigret) {
+		/* Set up the sigreturn trampoline: li r0,sigret; sc */
+		if (__put_user(0x38000000UL + sigret, &frame->tramp[0])
+		    || __put_user(0x44000002UL, &frame->tramp[1]))
+			return 1;
+		flush_icache_range((unsigned long) &frame->tramp[0],
+				   (unsigned long) &frame->tramp[2]);
+	}
+
+	return 0;
+}
+
+/*
+ * Restore the current user register values from the user stack,
+ * (except for MSR).
+ */
+static long restore_user_regs(struct pt_regs *regs,
+			      struct mcontext __user *sr, int sig)
+{
+	long err;
+	unsigned int save_r2 = 0;
+#if defined(CONFIG_ALTIVEC) || defined(CONFIG_SPE)
+	unsigned long msr;
+#endif
+
+	/*
+	 * restore general registers but not including MSR or SOFTE. Also
+	 * take care of keeping r2 (TLS) intact if not a signal
+	 */
+	if (!sig)
+		save_r2 = (unsigned int)regs->gpr[2];
+	err = restore_general_regs(regs, sr);
+	if (!sig)
+		regs->gpr[2] = (unsigned long) save_r2;
+	if (err)
+		return 1;
+
+	/* force the process to reload the FP registers from
+	   current->thread when it next does FP instructions */
+	regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
+	if (__copy_from_user(current->thread.fpr, &sr->mc_fregs,
+			     sizeof(sr->mc_fregs)))
+		return 1;
+
+#ifdef CONFIG_ALTIVEC
+	/* force the process to reload the altivec registers from
+	   current->thread when it next does altivec instructions */
+	regs->msr &= ~MSR_VEC;
+	if (!__get_user(msr, &sr->mc_gregs[PT_MSR]) && (msr & MSR_VEC) != 0) {
+		/* restore altivec registers from the stack */
+		if (__copy_from_user(current->thread.vr, &sr->mc_vregs,
+				     sizeof(sr->mc_vregs)))
+			return 1;
+	} else if (current->thread.used_vr)
+		memset(current->thread.vr, 0, ELF_NVRREG * sizeof(vector128));
+
+	/* Always get VRSAVE back */
+	if (__get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32]))
+		return 1;
+#endif /* CONFIG_ALTIVEC */
+
+#ifdef CONFIG_SPE
+	/* force the process to reload the spe registers from
+	   current->thread when it next does spe instructions */
+	regs->msr &= ~MSR_SPE;
+	if (!__get_user(msr, &sr->mc_gregs[PT_MSR]) && (msr & MSR_SPE) != 0) {
+		/* restore spe registers from the stack */
+		if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
+				     ELF_NEVRREG * sizeof(u32)))
+			return 1;
+	} else if (current->thread.used_spe)
+		memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
+
+	/* Always get SPEFSCR back */
+	if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs + ELF_NEVRREG))
+		return 1;
+#endif /* CONFIG_SPE */
+
+#ifndef CONFIG_SMP
+	preempt_disable();
+	if (last_task_used_math == current)
+		last_task_used_math = NULL;
+	if (last_task_used_altivec == current)
+		last_task_used_altivec = NULL;
+#ifdef CONFIG_SPE
+	if (last_task_used_spe == current)
+		last_task_used_spe = NULL;
+#endif
+	preempt_enable();
+#endif
+	return 0;
+}
+
+#ifdef CONFIG_PPC64
+long sys32_rt_sigaction(int sig, const struct sigaction32 __user *act,
+		struct sigaction32 __user *oact, size_t sigsetsize)
+{
+	struct k_sigaction new_ka, old_ka;
+	int ret;
+
+	/* XXX: Don't preclude handling different sized sigset_t's.  */
+	if (sigsetsize != sizeof(compat_sigset_t))
+		return -EINVAL;
+
+	if (act) {
+		compat_uptr_t handler;
+
+		ret = get_user(handler, &act->sa_handler);
+		new_ka.sa.sa_handler = compat_ptr(handler);
+		ret |= get_sigset_t(&new_ka.sa.sa_mask, &act->sa_mask);
+		ret |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
+		if (ret)
+			return -EFAULT;
+	}
+
+	ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
+	if (!ret && oact) {
+		ret = put_user((long)old_ka.sa.sa_handler, &oact->sa_handler);
+		ret |= put_sigset_t(&oact->sa_mask, &old_ka.sa.sa_mask);
+		ret |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
+	}
+	return ret;
+}
+
+/*
+ * Note: it is necessary to treat how as an unsigned int, with the
+ * corresponding cast to a signed int to insure that the proper
+ * conversion (sign extension) between the register representation
+ * of a signed int (msr in 32-bit mode) and the register representation
+ * of a signed int (msr in 64-bit mode) is performed.
+ */
+long sys32_rt_sigprocmask(u32 how, compat_sigset_t __user *set,
+		compat_sigset_t __user *oset, size_t sigsetsize)
+{
+	sigset_t s;
+	sigset_t __user *up;
+	int ret;
+	mm_segment_t old_fs = get_fs();
+
+	if (set) {
+		if (get_sigset_t(&s, set))
+			return -EFAULT;
+	}
+
+	set_fs(KERNEL_DS);
+	/* This is valid because of the set_fs() */
+	up = (sigset_t __user *) &s;
+	ret = sys_rt_sigprocmask((int)how, set ? up : NULL, oset ? up : NULL,
+				 sigsetsize);
+	set_fs(old_fs);
+	if (ret)
+		return ret;
+	if (oset) {
+		if (put_sigset_t(oset, &s))
+			return -EFAULT;
+	}
+	return 0;
+}
+
+long sys32_rt_sigpending(compat_sigset_t __user *set, compat_size_t sigsetsize)
+{
+	sigset_t s;
+	int ret;
+	mm_segment_t old_fs = get_fs();
+
+	set_fs(KERNEL_DS);
+	/* The __user pointer cast is valid because of the set_fs() */
+	ret = sys_rt_sigpending((sigset_t __user *) &s, sigsetsize);
+	set_fs(old_fs);
+	if (!ret) {
+		if (put_sigset_t(set, &s))
+			return -EFAULT;
+	}
+	return ret;
+}
+
+
+int copy_siginfo_to_user32(struct compat_siginfo __user *d, siginfo_t *s)
+{
+	int err;
+
+	if (!access_ok (VERIFY_WRITE, d, sizeof(*d)))
+		return -EFAULT;
+
+	/* If you change siginfo_t structure, please be sure
+	 * this code is fixed accordingly.
+	 * It should never copy any pad contained in the structure
+	 * to avoid security leaks, but must copy the generic
+	 * 3 ints plus the relevant union member.
+	 * This routine must convert siginfo from 64bit to 32bit as well
+	 * at the same time.
+	 */
+	err = __put_user(s->si_signo, &d->si_signo);
+	err |= __put_user(s->si_errno, &d->si_errno);
+	err |= __put_user((short)s->si_code, &d->si_code);
+	if (s->si_code < 0)
+		err |= __copy_to_user(&d->_sifields._pad, &s->_sifields._pad,
+				      SI_PAD_SIZE32);
+	else switch(s->si_code >> 16) {
+	case __SI_CHLD >> 16:
+		err |= __put_user(s->si_pid, &d->si_pid);
+		err |= __put_user(s->si_uid, &d->si_uid);
+		err |= __put_user(s->si_utime, &d->si_utime);
+		err |= __put_user(s->si_stime, &d->si_stime);
+		err |= __put_user(s->si_status, &d->si_status);
+		break;
+	case __SI_FAULT >> 16:
+		err |= __put_user((unsigned int)(unsigned long)s->si_addr,
+				  &d->si_addr);
+		break;
+	case __SI_POLL >> 16:
+		err |= __put_user(s->si_band, &d->si_band);
+		err |= __put_user(s->si_fd, &d->si_fd);
+		break;
+	case __SI_TIMER >> 16:
+		err |= __put_user(s->si_tid, &d->si_tid);
+		err |= __put_user(s->si_overrun, &d->si_overrun);
+		err |= __put_user(s->si_int, &d->si_int);
+		break;
+	case __SI_RT >> 16: /* This is not generated by the kernel as of now.  */
+	case __SI_MESGQ >> 16:
+		err |= __put_user(s->si_int, &d->si_int);
+		/* fallthrough */
+	case __SI_KILL >> 16:
+	default:
+		err |= __put_user(s->si_pid, &d->si_pid);
+		err |= __put_user(s->si_uid, &d->si_uid);
+		break;
+	}
+	return err;
+}
+
+#define copy_siginfo_to_user	copy_siginfo_to_user32
+
+/*
+ * Note: it is necessary to treat pid and sig as unsigned ints, with the
+ * corresponding cast to a signed int to insure that the proper conversion
+ * (sign extension) between the register representation of a signed int
+ * (msr in 32-bit mode) and the register representation of a signed int
+ * (msr in 64-bit mode) is performed.
+ */
+long sys32_rt_sigqueueinfo(u32 pid, u32 sig, compat_siginfo_t __user *uinfo)
+{
+	siginfo_t info;
+	int ret;
+	mm_segment_t old_fs = get_fs();
+
+	if (copy_from_user (&info, uinfo, 3*sizeof(int)) ||
+	    copy_from_user (info._sifields._pad, uinfo->_sifields._pad, SI_PAD_SIZE32))
+		return -EFAULT;
+	set_fs (KERNEL_DS);
+	/* The __user pointer cast is valid becasuse of the set_fs() */
+	ret = sys_rt_sigqueueinfo((int)pid, (int)sig, (siginfo_t __user *) &info);
+	set_fs (old_fs);
+	return ret;
+}
+/*
+ *  Start Alternate signal stack support
+ *
+ *  System Calls
+ *       sigaltatck               sys32_sigaltstack
+ */
+
+int sys32_sigaltstack(u32 __new, u32 __old, int r5,
+		      int r6, int r7, int r8, struct pt_regs *regs)
+{
+	stack_32_t __user * newstack = (stack_32_t __user *)(long) __new;
+	stack_32_t __user * oldstack = (stack_32_t __user *)(long) __old;
+	stack_t uss, uoss;
+	int ret;
+	mm_segment_t old_fs;
+	unsigned long sp;
+	compat_uptr_t ss_sp;
+
+	/*
+	 * set sp to the user stack on entry to the system call
+	 * the system call router sets R9 to the saved registers
+	 */
+	sp = regs->gpr[1];
+
+	/* Put new stack info in local 64 bit stack struct */
+	if (newstack) {
+		if (get_user(ss_sp, &newstack->ss_sp) ||
+		    __get_user(uss.ss_flags, &newstack->ss_flags) ||
+		    __get_user(uss.ss_size, &newstack->ss_size))
+			return -EFAULT;
+		uss.ss_sp = compat_ptr(ss_sp);
+	}
+
+	old_fs = get_fs();
+	set_fs(KERNEL_DS);
+	/* The __user pointer casts are valid because of the set_fs() */
+	ret = do_sigaltstack(
+		newstack ? (stack_t __user *) &uss : NULL,
+		oldstack ? (stack_t __user *) &uoss : NULL,
+		sp);
+	set_fs(old_fs);
+	/* Copy the stack information to the user output buffer */
+	if (!ret && oldstack  &&
+		(put_user((long)uoss.ss_sp, &oldstack->ss_sp) ||
+		 __put_user(uoss.ss_flags, &oldstack->ss_flags) ||
+		 __put_user(uoss.ss_size, &oldstack->ss_size)))
+		return -EFAULT;
+	return ret;
+}
+#endif /* CONFIG_PPC64 */
+
+
+/*
+ * Restore the user process's signal mask
+ */
+#ifdef CONFIG_PPC64
+extern void restore_sigmask(sigset_t *set);
+#else /* CONFIG_PPC64 */
+static void restore_sigmask(sigset_t *set)
+{
+	sigdelsetmask(set, ~_BLOCKABLE);
+	spin_lock_irq(&current->sighand->siglock);
+	current->blocked = *set;
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
+}
+#endif
+
+/*
+ * Set up a signal frame for a "real-time" signal handler
+ * (one which gets siginfo).
+ */
+static int handle_rt_signal(unsigned long sig, struct k_sigaction *ka,
+		siginfo_t *info, sigset_t *oldset,
+		struct pt_regs *regs, unsigned long newsp)
+{
+	struct rt_sigframe __user *rt_sf;
+	struct mcontext __user *frame;
+	unsigned long origsp = newsp;
+
+	/* Set up Signal Frame */
+	/* Put a Real Time Context onto stack */
+	newsp -= sizeof(*rt_sf);
+	rt_sf = (struct rt_sigframe __user *)newsp;
+
+	/* create a stack frame for the caller of the handler */
+	newsp -= __SIGNAL_FRAMESIZE + 16;
+
+	if (!access_ok(VERIFY_WRITE, (void __user *)newsp, origsp - newsp))
+		goto badframe;
+
+	/* Put the siginfo & fill in most of the ucontext */
+	if (copy_siginfo_to_user(&rt_sf->info, info)
+	    || __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)
+	    || __put_user(to_user_ptr(&rt_sf->uc.uc_mcontext),
+		    &rt_sf->uc.uc_regs)
+	    || put_sigset_t(&rt_sf->uc.uc_sigmask, oldset))
+		goto badframe;
+
+	/* Save user registers on the stack */
+	frame = &rt_sf->uc.uc_mcontext;
+#ifdef CONFIG_PPC64
+	if (vdso32_rt_sigtramp && current->thread.vdso_base) {
+		if (save_user_regs(regs, frame, 0))
+			goto badframe;
+		regs->link = current->thread.vdso_base + vdso32_rt_sigtramp;
+	} else
+#endif
+	{
+		if (save_user_regs(regs, frame, __NR_rt_sigreturn))
+			goto badframe;
+		regs->link = (unsigned long) frame->tramp;
+	}
+	if (put_user(regs->gpr[1], (unsigned long __user *)newsp))
+		goto badframe;
+	regs->gpr[1] = newsp;
+	regs->gpr[3] = sig;
+	regs->gpr[4] = (unsigned long) &rt_sf->info;
+	regs->gpr[5] = (unsigned long) &rt_sf->uc;
+	regs->gpr[6] = (unsigned long) rt_sf;
+	regs->nip = (unsigned long) ka->sa.sa_handler;
+	regs->link = (unsigned long) frame->tramp;
+	regs->trap = 0;
+#ifdef CONFIG_PPC64
+	regs->result = 0;
+
+	if (test_thread_flag(TIF_SINGLESTEP))
+		ptrace_notify(SIGTRAP);
+#endif
+	return 1;
+
+badframe:
+#ifdef DEBUG_SIG
+	printk("badframe in handle_rt_signal, regs=%p frame=%p newsp=%lx\n",
+	       regs, frame, newsp);
+#endif
+	force_sigsegv(sig, current);
+	return 0;
+}
+
+static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int sig)
+{
+	sigset_t set;
+	struct mcontext __user *mcp;
+
+	if (get_sigset_t(&set, &ucp->uc_sigmask))
+		return -EFAULT;
+#ifdef CONFIG_PPC64
+	{
+		u32 cmcp;
+
+		if (__get_user(cmcp, &ucp->uc_regs))
+			return -EFAULT;
+		mcp = (struct mcontext __user *)(u64)cmcp;
+	}
+#else
+	if (__get_user(mcp, &ucp->uc_regs))
+		return -EFAULT;
+#endif
+	restore_sigmask(&set);
+	if (restore_user_regs(regs, mcp, sig))
+		return -EFAULT;
+
+	return 0;
+}
+
+long sys_swapcontext(struct ucontext __user *old_ctx,
+		       struct ucontext __user *new_ctx,
+		       int ctx_size, int r6, int r7, int r8, struct pt_regs *regs)
+{
+	unsigned char tmp;
+
+	/* Context size is for future use. Right now, we only make sure
+	 * we are passed something we understand
+	 */
+	if (ctx_size < sizeof(struct ucontext))
+		return -EINVAL;
+
+	if (old_ctx != NULL) {
+		if (!access_ok(VERIFY_WRITE, old_ctx, sizeof(*old_ctx))
+		    || save_user_regs(regs, &old_ctx->uc_mcontext, 0)
+		    || put_sigset_t(&old_ctx->uc_sigmask, &current->blocked)
+		    || __put_user(to_user_ptr(&old_ctx->uc_mcontext),
+			    &old_ctx->uc_regs))
+			return -EFAULT;
+	}
+	if (new_ctx == NULL)
+		return 0;
+	if (!access_ok(VERIFY_READ, new_ctx, sizeof(*new_ctx))
+	    || __get_user(tmp, (u8 __user *) new_ctx)
+	    || __get_user(tmp, (u8 __user *) (new_ctx + 1) - 1))
+		return -EFAULT;
+
+	/*
+	 * If we get a fault copying the context into the kernel's
+	 * image of the user's registers, we can't just return -EFAULT
+	 * because the user's registers will be corrupted.  For instance
+	 * the NIP value may have been updated but not some of the
+	 * other registers.  Given that we have done the access_ok
+	 * and successfully read the first and last bytes of the region
+	 * above, this should only happen in an out-of-memory situation
+	 * or if another thread unmaps the region containing the context.
+	 * We kill the task with a SIGSEGV in this situation.
+	 */
+	if (do_setcontext(new_ctx, regs, 0))
+		do_exit(SIGSEGV);
+	sigreturn_exit(regs);
+	/* doesn't actually return back to here */
+	return 0;
+}
+
+long sys_rt_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8,
+		     struct pt_regs *regs)
+{
+	struct rt_sigframe __user *rt_sf;
+
+	/* Always make any pending restarted system calls return -EINTR */
+	current_thread_info()->restart_block.fn = do_no_restart_syscall;
+
+	rt_sf = (struct rt_sigframe __user *)
+		(regs->gpr[1] + __SIGNAL_FRAMESIZE + 16);
+	if (!access_ok(VERIFY_READ, rt_sf, sizeof(*rt_sf)))
+		goto bad;
+	if (do_setcontext(&rt_sf->uc, regs, 1))
+		goto bad;
+
+	/*
+	 * It's not clear whether or why it is desirable to save the
+	 * sigaltstack setting on signal delivery and restore it on
+	 * signal return.  But other architectures do this and we have
+	 * always done it up until now so it is probably better not to
+	 * change it.  -- paulus
+	 */
+#ifdef CONFIG_PPC64
+	/*
+	 * We use the sys32_ version that does the 32/64 bits conversion
+	 * and takes userland pointer directly. What about error checking ?
+	 * nobody does any...
+	 */
+	sys32_sigaltstack((u32)(u64)&rt_sf->uc.uc_stack, 0, 0, 0, 0, 0, regs);
+	return (int)regs->result;
+#else
+	do_sigaltstack(&rt_sf->uc.uc_stack, NULL, regs->gpr[1]);
+	sigreturn_exit(regs);		/* doesn't return here */
+	return 0;
+#endif
+
+ bad:
+	force_sig(SIGSEGV, current);
+	return 0;
+}
+
+#ifdef CONFIG_PPC32
+int sys_debug_setcontext(struct ucontext __user *ctx,
+			 int ndbg, struct sig_dbg_op __user *dbg,
+			 int r6, int r7, int r8,
+			 struct pt_regs *regs)
+{
+	struct sig_dbg_op op;
+	int i;
+	unsigned long new_msr = regs->msr;
+#if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
+	unsigned long new_dbcr0 = current->thread.dbcr0;
+#endif
+
+	for (i=0; i<ndbg; i++) {
+		if (__copy_from_user(&op, dbg, sizeof(op)))
+			return -EFAULT;
+		switch (op.dbg_type) {
+		case SIG_DBG_SINGLE_STEPPING:
+#if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
+			if (op.dbg_value) {
+				new_msr |= MSR_DE;
+				new_dbcr0 |= (DBCR0_IDM | DBCR0_IC);
+			} else {
+				new_msr &= ~MSR_DE;
+				new_dbcr0 &= ~(DBCR0_IDM | DBCR0_IC);
+			}
+#else
+			if (op.dbg_value)
+				new_msr |= MSR_SE;
+			else
+				new_msr &= ~MSR_SE;
+#endif
+			break;
+		case SIG_DBG_BRANCH_TRACING:
+#if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
+			return -EINVAL;
+#else
+			if (op.dbg_value)
+				new_msr |= MSR_BE;
+			else
+				new_msr &= ~MSR_BE;
+#endif
+			break;
+
+		default:
+			return -EINVAL;
+		}
+	}
+
+	/* We wait until here to actually install the values in the
+	   registers so if we fail in the above loop, it will not
+	   affect the contents of these registers.  After this point,
+	   failure is a problem, anyway, and it's very unlikely unless
+	   the user is really doing something wrong. */
+	regs->msr = new_msr;
+#if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
+	current->thread.dbcr0 = new_dbcr0;
+#endif
+
+	/*
+	 * If we get a fault copying the context into the kernel's
+	 * image of the user's registers, we can't just return -EFAULT
+	 * because the user's registers will be corrupted.  For instance
+	 * the NIP value may have been updated but not some of the
+	 * other registers.  Given that we have done the access_ok
+	 * and successfully read the first and last bytes of the region
+	 * above, this should only happen in an out-of-memory situation
+	 * or if another thread unmaps the region containing the context.
+	 * We kill the task with a SIGSEGV in this situation.
+	 */
+	if (do_setcontext(ctx, regs, 1)) {
+		force_sig(SIGSEGV, current);
+		goto out;
+	}
+
+	/*
+	 * It's not clear whether or why it is desirable to save the
+	 * sigaltstack setting on signal delivery and restore it on
+	 * signal return.  But other architectures do this and we have
+	 * always done it up until now so it is probably better not to
+	 * change it.  -- paulus
+	 */
+	do_sigaltstack(&ctx->uc_stack, NULL, regs->gpr[1]);
+
+	sigreturn_exit(regs);
+	/* doesn't actually return back to here */
+
+ out:
+	return 0;
+}
+#endif
+
+/*
+ * OK, we're invoking a handler
+ */
+static int handle_signal(unsigned long sig, struct k_sigaction *ka,
+		siginfo_t *info, sigset_t *oldset, struct pt_regs *regs,
+		unsigned long newsp)
+{
+	struct sigcontext __user *sc;
+	struct sigregs __user *frame;
+	unsigned long origsp = newsp;
+
+	/* Set up Signal Frame */
+	newsp -= sizeof(struct sigregs);
+	frame = (struct sigregs __user *) newsp;
+
+	/* Put a sigcontext on the stack */
+	newsp -= sizeof(*sc);
+	sc = (struct sigcontext __user *) newsp;
+
+	/* create a stack frame for the caller of the handler */
+	newsp -= __SIGNAL_FRAMESIZE;
+
+	if (!access_ok(VERIFY_WRITE, (void __user *) newsp, origsp - newsp))
+		goto badframe;
+
+#if _NSIG != 64
+#error "Please adjust handle_signal()"
+#endif
+	if (__put_user(to_user_ptr(ka->sa.sa_handler), &sc->handler)
+	    || __put_user(oldset->sig[0], &sc->oldmask)
+#ifdef CONFIG_PPC64
+	    || __put_user((oldset->sig[0] >> 32), &sc->_unused[3])
+#else
+	    || __put_user(oldset->sig[1], &sc->_unused[3])
+#endif
+	    || __put_user(to_user_ptr(frame), &sc->regs)
+	    || __put_user(sig, &sc->signal))
+		goto badframe;
+
+#ifdef CONFIG_PPC64
+	if (vdso32_sigtramp && current->thread.vdso_base) {
+		if (save_user_regs(regs, &frame->mctx, 0))
+			goto badframe;
+		regs->link = current->thread.vdso_base + vdso32_sigtramp;
+	} else
+#endif
+	{
+		if (save_user_regs(regs, &frame->mctx, __NR_sigreturn))
+			goto badframe;
+		regs->link = (unsigned long) frame->mctx.tramp;
+	}
+
+	if (put_user(regs->gpr[1], (u32 __user *)newsp))
+		goto badframe;
+	regs->gpr[1] = newsp;
+	regs->gpr[3] = sig;
+	regs->gpr[4] = (unsigned long) sc;
+	regs->nip = (unsigned long) ka->sa.sa_handler;
+	regs->trap = 0;
+#ifdef CONFIG_PPC64
+	regs->result = 0;
+
+	if (test_thread_flag(TIF_SINGLESTEP))
+		ptrace_notify(SIGTRAP);
+#endif
+
+	return 1;
+
+badframe:
+#ifdef DEBUG_SIG
+	printk("badframe in handle_signal, regs=%p frame=%p newsp=%lx\n",
+	       regs, frame, newsp);
+#endif
+	force_sigsegv(sig, current);
+	return 0;
+}
+
+/*
+ * Do a signal return; undo the signal stack.
+ */
+long sys_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8,
+		       struct pt_regs *regs)
+{
+	struct sigcontext __user *sc;
+	struct sigcontext sigctx;
+	struct mcontext __user *sr;
+	sigset_t set;
+
+	/* Always make any pending restarted system calls return -EINTR */
+	current_thread_info()->restart_block.fn = do_no_restart_syscall;
+
+	sc = (struct sigcontext __user *)(regs->gpr[1] + __SIGNAL_FRAMESIZE);
+	if (copy_from_user(&sigctx, sc, sizeof(sigctx)))
+		goto badframe;
+
+#ifdef CONFIG_PPC64
+	/*
+	 * Note that PPC32 puts the upper 32 bits of the sigmask in the
+	 * unused part of the signal stackframe
+	 */
+	set.sig[0] = sigctx.oldmask + ((long)(sigctx._unused[3]) << 32);
+#else
+	set.sig[0] = sigctx.oldmask;
+	set.sig[1] = sigctx._unused[3];
+#endif
+	restore_sigmask(&set);
+
+	sr = (struct mcontext __user *)from_user_ptr(sigctx.regs);
+	if (!access_ok(VERIFY_READ, sr, sizeof(*sr))
+	    || restore_user_regs(regs, sr, 1))
+		goto badframe;
+
+#ifdef CONFIG_PPC64
+	return (int)regs->result;
+#else
+	sigreturn_exit(regs);		/* doesn't return */
+	return 0;
+#endif
+
+badframe:
+	force_sig(SIGSEGV, current);
+	return 0;
+}
+
+/*
+ * 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.
+ */
+int do_signal(sigset_t *oldset, struct pt_regs *regs)
+{
+	siginfo_t info;
+	struct k_sigaction ka;
+	unsigned int frame, newsp;
+	int signr, ret;
+
+#ifdef CONFIG_PPC32
+	if (try_to_freeze()) {
+		signr = 0;
+		if (!signal_pending(current))
+			goto no_signal;
+	}
+#endif
+
+	if (!oldset)
+		oldset = &current->blocked;
+
+	newsp = frame = 0;
+
+	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
+#ifdef CONFIG_PPC32
+no_signal:
+#endif
+	if (TRAP(regs) == 0x0C00		/* System Call! */
+	    && regs->ccr & 0x10000000		/* error signalled */
+	    && ((ret = regs->gpr[3]) == ERESTARTSYS
+		|| ret == ERESTARTNOHAND || ret == ERESTARTNOINTR
+		|| ret == ERESTART_RESTARTBLOCK)) {
+
+		if (signr > 0
+		    && (ret == ERESTARTNOHAND || ret == ERESTART_RESTARTBLOCK
+			|| (ret == ERESTARTSYS
+			    && !(ka.sa.sa_flags & SA_RESTART)))) {
+			/* make the system call return an EINTR error */
+			regs->result = -EINTR;
+			regs->gpr[3] = EINTR;
+			/* note that the cr0.SO bit is already set */
+		} else {
+			regs->nip -= 4;	/* Back up & retry system call */
+			regs->result = 0;
+			regs->trap = 0;
+			if (ret == ERESTART_RESTARTBLOCK)
+				regs->gpr[0] = __NR_restart_syscall;
+			else
+				regs->gpr[3] = regs->orig_gpr3;
+		}
+	}
+
+	if (signr == 0)
+		return 0;		/* no signals delivered */
+
+	if ((ka.sa.sa_flags & SA_ONSTACK) && current->sas_ss_size
+	    && !on_sig_stack(regs->gpr[1]))
+		newsp = current->sas_ss_sp + current->sas_ss_size;
+	else
+		newsp = regs->gpr[1];
+	newsp &= ~0xfUL;
+
+#ifdef CONFIG_PPC64
+	/*
+	 * Reenable the DABR before delivering the signal to
+	 * user space. The DABR will have been cleared if it
+	 * triggered inside the kernel.
+	 */
+	if (current->thread.dabr)
+		set_dabr(current->thread.dabr);
+#endif
+
+	/* Whee!  Actually deliver the signal.  */
+	if (ka.sa.sa_flags & SA_SIGINFO)
+		ret = handle_rt_signal(signr, &ka, &info, oldset, regs, newsp);
+	else
+		ret = handle_signal(signr, &ka, &info, oldset, regs, newsp);
+
+	if (ret) {
+		spin_lock_irq(&current->sighand->siglock);
+		sigorsets(&current->blocked, &current->blocked,
+			  &ka.sa.sa_mask);
+		if (!(ka.sa.sa_flags & SA_NODEFER))
+			sigaddset(&current->blocked, signr);
+		recalc_sigpending();
+		spin_unlock_irq(&current->sighand->siglock);
+	}
+
+	return ret;
+}