2005-04-16 22:20:36 +00:00
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/*
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* PowerPC version
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* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
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*
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* Derived from "arch/i386/kernel/signal.c"
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* Copyright (C) 1991, 1992 Linus Torvalds
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* 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/sched.h>
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#include <linux/mm.h>
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#include <linux/smp.h>
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#include <linux/kernel.h>
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#include <linux/signal.h>
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#include <linux/errno.h>
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#include <linux/wait.h>
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#include <linux/unistd.h>
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#include <linux/stddef.h>
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#include <linux/elf.h>
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#include <linux/ptrace.h>
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#include <linux/module.h>
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#include <asm/sigcontext.h>
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#include <asm/ucontext.h>
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#include <asm/uaccess.h>
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#include <asm/pgtable.h>
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#include <asm/unistd.h>
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#include <asm/cacheflush.h>
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2006-03-22 23:00:08 +00:00
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#include <asm/syscalls.h>
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2005-04-16 22:20:36 +00:00
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#include <asm/vdso.h>
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2007-06-04 05:15:49 +00:00
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#include "signal.h"
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2005-04-16 22:20:36 +00:00
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#define DEBUG_SIG 0
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2005-05-06 02:10:04 +00:00
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#define GP_REGS_SIZE min(sizeof(elf_gregset_t), sizeof(struct pt_regs))
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2005-04-16 22:20:36 +00:00
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#define FP_REGS_SIZE sizeof(elf_fpregset_t)
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#define TRAMP_TRACEBACK 3
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#define TRAMP_SIZE 6
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/*
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* When we have signals to deliver, we set up on the user stack,
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* going down from the original stack pointer:
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* 1) a rt_sigframe struct which contains the ucontext
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* 2) a gap of __SIGNAL_FRAMESIZE bytes which acts as a dummy caller
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* frame for the signal handler.
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*/
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struct rt_sigframe {
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/* sys_rt_sigreturn requires the ucontext be the first field */
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struct ucontext uc;
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unsigned long _unused[2];
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unsigned int tramp[TRAMP_SIZE];
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2006-02-01 10:28:09 +00:00
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struct siginfo __user *pinfo;
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void __user *puc;
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2005-04-16 22:20:36 +00:00
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struct siginfo info;
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/* 64 bit ABI allows for 288 bytes below sp before decrementing it. */
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char abigap[288];
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} __attribute__ ((aligned (16)));
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2007-10-12 00:20:07 +00:00
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static const char fmt32[] = KERN_INFO \
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"%s[%d]: bad frame in %s: %08lx nip %08lx lr %08lx\n";
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static const char fmt64[] = KERN_INFO \
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"%s[%d]: bad frame in %s: %016lx nip %016lx lr %016lx\n";
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2005-04-16 22:20:36 +00:00
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/*
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* Set up the sigcontext for the signal frame.
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*/
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static long setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
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int signr, sigset_t *set, unsigned long handler)
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{
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/* When CONFIG_ALTIVEC is set, we _always_ setup v_regs even if the
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* process never used altivec yet (MSR_VEC is zero in pt_regs of
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* the context). This is very important because we must ensure we
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* don't lose the VRSAVE content that may have been set prior to
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* the process doing its first vector operation
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* Userland shall check AT_HWCAP to know wether it can rely on the
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* v_regs pointer or not
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*/
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#ifdef CONFIG_ALTIVEC
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elf_vrreg_t __user *v_regs = (elf_vrreg_t __user *)(((unsigned long)sc->vmx_reserve + 15) & ~0xful);
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#endif
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2008-06-02 06:22:59 +00:00
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unsigned long msr = regs->msr;
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2005-04-16 22:20:36 +00:00
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long err = 0;
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flush_fp_to_thread(current);
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#ifdef CONFIG_ALTIVEC
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err |= __put_user(v_regs, &sc->v_regs);
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/* save altivec registers */
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if (current->thread.used_vr) {
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flush_altivec_to_thread(current);
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/* Copy 33 vec registers (vr0..31 and vscr) to the stack */
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err |= __copy_to_user(v_regs, current->thread.vr, 33 * sizeof(vector128));
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/* set MSR_VEC in the MSR value in the frame to indicate that sc->v_reg)
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* contains valid data.
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*/
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2008-06-02 06:22:59 +00:00
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msr |= MSR_VEC;
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2005-04-16 22:20:36 +00:00
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}
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/* We always copy to/from vrsave, it's 0 if we don't have or don't
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* use altivec.
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*/
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err |= __put_user(current->thread.vrsave, (u32 __user *)&v_regs[33]);
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#else /* CONFIG_ALTIVEC */
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err |= __put_user(0, &sc->v_regs);
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#endif /* CONFIG_ALTIVEC */
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2008-06-25 04:07:18 +00:00
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flush_fp_to_thread(current);
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2008-07-02 04:06:37 +00:00
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/* copy fpr regs and fpscr */
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err |= copy_fpr_to_user(&sc->fp_regs, current);
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2008-06-25 04:07:18 +00:00
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#ifdef CONFIG_VSX
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2008-06-25 04:07:18 +00:00
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/*
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* Copy VSX low doubleword to local buffer for formatting,
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* then out to userspace. Update v_regs to point after the
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* VMX data.
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*/
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if (current->thread.used_vsr) {
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flush_vsx_to_thread(current);
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v_regs += ELF_NVRREG;
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2008-07-02 04:06:37 +00:00
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err |= copy_vsx_to_user(v_regs, current);
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2008-06-25 04:07:18 +00:00
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/* set MSR_VSX in the MSR value in the frame to
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* indicate that sc->vs_reg) contains valid data.
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*/
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msr |= MSR_VSX;
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}
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2008-06-25 04:07:18 +00:00
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#endif /* CONFIG_VSX */
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2005-04-16 22:20:36 +00:00
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err |= __put_user(&sc->gp_regs, &sc->regs);
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2006-03-08 02:24:22 +00:00
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WARN_ON(!FULL_REGS(regs));
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2005-04-16 22:20:36 +00:00
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err |= __copy_to_user(&sc->gp_regs, regs, GP_REGS_SIZE);
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2008-06-02 06:22:59 +00:00
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err |= __put_user(msr, &sc->gp_regs[PT_MSR]);
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2005-04-16 22:20:36 +00:00
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err |= __put_user(signr, &sc->signal);
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err |= __put_user(handler, &sc->handler);
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if (set != NULL)
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err |= __put_user(set->sig[0], &sc->oldmask);
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return err;
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}
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/*
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* Restore the sigcontext from the signal frame.
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*/
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static long restore_sigcontext(struct pt_regs *regs, sigset_t *set, int sig,
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struct sigcontext __user *sc)
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{
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#ifdef CONFIG_ALTIVEC
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elf_vrreg_t __user *v_regs;
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#endif
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unsigned long err = 0;
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unsigned long save_r13 = 0;
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unsigned long msr;
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2008-07-02 04:06:37 +00:00
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#ifdef CONFIG_VSX
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int i;
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#endif
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2005-04-16 22:20:36 +00:00
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/* If this is not a signal return, we preserve the TLS in r13 */
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if (!sig)
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save_r13 = regs->gpr[13];
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2008-06-27 06:18:27 +00:00
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/* copy the GPRs */
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err |= __copy_from_user(regs->gpr, sc->gp_regs, sizeof(regs->gpr));
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err |= __get_user(regs->nip, &sc->gp_regs[PT_NIP]);
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2006-06-07 06:14:40 +00:00
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/* get MSR separately, transfer the LE bit if doing signal return */
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err |= __get_user(msr, &sc->gp_regs[PT_MSR]);
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if (sig)
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regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
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2008-06-27 06:18:27 +00:00
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err |= __get_user(regs->orig_gpr3, &sc->gp_regs[PT_ORIG_R3]);
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err |= __get_user(regs->ctr, &sc->gp_regs[PT_CTR]);
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err |= __get_user(regs->link, &sc->gp_regs[PT_LNK]);
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err |= __get_user(regs->xer, &sc->gp_regs[PT_XER]);
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err |= __get_user(regs->ccr, &sc->gp_regs[PT_CCR]);
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2006-06-07 06:14:40 +00:00
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/* skip SOFTE */
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2008-06-27 06:18:27 +00:00
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err |= __get_user(regs->trap, &sc->gp_regs[PT_TRAP]);
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err |= __get_user(regs->dar, &sc->gp_regs[PT_DAR]);
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err |= __get_user(regs->dsisr, &sc->gp_regs[PT_DSISR]);
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err |= __get_user(regs->result, &sc->gp_regs[PT_RESULT]);
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2005-04-16 22:20:36 +00:00
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if (!sig)
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regs->gpr[13] = save_r13;
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if (set != NULL)
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err |= __get_user(set->sig[0], &sc->oldmask);
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2006-01-11 11:11:39 +00:00
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/*
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* Do this before updating the thread state in
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* current->thread.fpr/vr. That way, if we get preempted
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* and another task grabs the FPU/Altivec, it won't be
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* tempted to save the current CPU state into the thread_struct
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* and corrupt what we are writing there.
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*/
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discard_lazy_cpu_state();
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2007-06-26 04:49:11 +00:00
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/*
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* Force reload of FP/VEC.
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* This has to be done before copying stuff into current->thread.fpr/vr
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* for the reasons explained in the previous comment.
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*/
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2008-06-25 04:07:18 +00:00
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regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1 | MSR_VEC | MSR_VSX);
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2007-06-26 04:49:11 +00:00
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2005-04-16 22:20:36 +00:00
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#ifdef CONFIG_ALTIVEC
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err |= __get_user(v_regs, &sc->v_regs);
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if (err)
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return err;
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2006-06-09 03:02:59 +00:00
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if (v_regs && !access_ok(VERIFY_READ, v_regs, 34 * sizeof(vector128)))
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return -EFAULT;
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2005-04-16 22:20:36 +00:00
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/* Copy 33 vec registers (vr0..31 and vscr) from the stack */
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if (v_regs != 0 && (msr & MSR_VEC) != 0)
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err |= __copy_from_user(current->thread.vr, v_regs,
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33 * sizeof(vector128));
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else if (current->thread.used_vr)
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memset(current->thread.vr, 0, 33 * sizeof(vector128));
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/* Always get VRSAVE back */
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if (v_regs != 0)
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err |= __get_user(current->thread.vrsave, (u32 __user *)&v_regs[33]);
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else
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current->thread.vrsave = 0;
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#endif /* CONFIG_ALTIVEC */
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2008-06-25 04:07:18 +00:00
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/* restore floating point */
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2008-07-02 04:06:37 +00:00
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err |= copy_fpr_from_user(current, &sc->fp_regs);
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#ifdef CONFIG_VSX
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2008-06-25 04:07:18 +00:00
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/*
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* Get additional VSX data. Update v_regs to point after the
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* VMX data. Copy VSX low doubleword from userspace to local
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* buffer for formatting, then into the taskstruct.
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*/
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v_regs += ELF_NVRREG;
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if ((msr & MSR_VSX) != 0)
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2008-07-02 04:06:37 +00:00
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err |= copy_vsx_from_user(current, v_regs);
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2008-06-25 04:07:18 +00:00
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else
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2008-07-02 04:06:37 +00:00
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for (i = 0; i < 32 ; i++)
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current->thread.fpr[i][TS_VSRLOWOFFSET] = 0;
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2008-06-25 04:07:18 +00:00
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2008-06-25 04:07:18 +00:00
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#else
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#endif
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2005-04-16 22:20:36 +00:00
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return err;
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}
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/*
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* Setup the trampoline code on the stack
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*/
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static long setup_trampoline(unsigned int syscall, unsigned int __user *tramp)
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{
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int i;
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long err = 0;
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/* addi r1, r1, __SIGNAL_FRAMESIZE # Pop the dummy stackframe */
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err |= __put_user(0x38210000UL | (__SIGNAL_FRAMESIZE & 0xffff), &tramp[0]);
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/* li r0, __NR_[rt_]sigreturn| */
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err |= __put_user(0x38000000UL | (syscall & 0xffff), &tramp[1]);
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/* sc */
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err |= __put_user(0x44000002UL, &tramp[2]);
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/* Minimal traceback info */
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for (i=TRAMP_TRACEBACK; i < TRAMP_SIZE ;i++)
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err |= __put_user(0, &tramp[i]);
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if (!err)
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flush_icache_range((unsigned long) &tramp[0],
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(unsigned long) &tramp[TRAMP_SIZE]);
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return err;
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}
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/*
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* Handle {get,set,swap}_context operations
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*/
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int sys_swapcontext(struct ucontext __user *old_ctx,
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struct ucontext __user *new_ctx,
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long ctx_size, long r6, long r7, long r8, struct pt_regs *regs)
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{
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unsigned char tmp;
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sigset_t set;
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/* Context size is for future use. Right now, we only make sure
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* we are passed something we understand
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*/
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if (ctx_size < sizeof(struct ucontext))
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return -EINVAL;
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if (old_ctx != NULL) {
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if (!access_ok(VERIFY_WRITE, old_ctx, sizeof(*old_ctx))
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|| setup_sigcontext(&old_ctx->uc_mcontext, regs, 0, NULL, 0)
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|| __copy_to_user(&old_ctx->uc_sigmask,
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¤t->blocked, sizeof(sigset_t)))
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return -EFAULT;
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}
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if (new_ctx == NULL)
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return 0;
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if (!access_ok(VERIFY_READ, new_ctx, sizeof(*new_ctx))
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|| __get_user(tmp, (u8 __user *) new_ctx)
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|| __get_user(tmp, (u8 __user *) (new_ctx + 1) - 1))
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return -EFAULT;
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/*
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* If we get a fault copying the context into the kernel's
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* image of the user's registers, we can't just return -EFAULT
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* because the user's registers will be corrupted. For instance
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* the NIP value may have been updated but not some of the
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* other registers. Given that we have done the access_ok
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* and successfully read the first and last bytes of the region
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* above, this should only happen in an out-of-memory situation
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* or if another thread unmaps the region containing the context.
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|
|
* We kill the task with a SIGSEGV in this situation.
|
|
|
|
*/
|
|
|
|
|
|
|
|
if (__copy_from_user(&set, &new_ctx->uc_sigmask, sizeof(set)))
|
|
|
|
do_exit(SIGSEGV);
|
|
|
|
restore_sigmask(&set);
|
|
|
|
if (restore_sigcontext(regs, NULL, 0, &new_ctx->uc_mcontext))
|
|
|
|
do_exit(SIGSEGV);
|
|
|
|
|
|
|
|
/* This returns like rt_sigreturn */
|
[PATCH] syscall entry/exit revamp
This cleanup patch speeds up the null syscall path on ppc64 by about 3%,
and brings the ppc32 and ppc64 code slightly closer together.
The ppc64 code was checking current_thread_info()->flags twice in the
syscall exit path; once for TIF_SYSCALL_T_OR_A before disabling
interrupts, and then again for TIF_SIGPENDING|TIF_NEED_RESCHED etc after
disabling interrupts. Now we do the same as ppc32 -- check the flags
only once in the fast path, and re-enable interrupts if necessary in the
ptrace case.
The patch abolishes the 'syscall_noerror' member of struct thread_info
and replaces it with a TIF_NOERROR bit in the flags, which is handled in
the slow path. This shortens the syscall entry code, which no longer
needs to clear syscall_noerror.
The patch adds a TIF_SAVE_NVGPRS flag which causes the syscall exit slow
path to save the non-volatile GPRs into a signal frame. This removes the
need for the assembly wrappers around sys_sigsuspend(),
sys_rt_sigsuspend(), et al which existed solely to save those registers
in advance. It also means I don't have to add new wrappers for ppoll()
and pselect(), which is what I was supposed to be doing when I got
distracted into this...
Finally, it unifies the ppc64 and ppc32 methods of handling syscall exit
directly into a signal handler (as required by sigsuspend et al) by
introducing a TIF_RESTOREALL flag which causes _all_ the registers to be
reloaded from the pt_regs by taking the ret_from_exception path, instead
of the normal syscall exit path which stomps on the callee-saved GPRs.
It appears to pass an LTP test run on ppc64, and passes basic testing on
ppc32 too. Brief tests of ptrace functionality with strace and gdb also
appear OK. I wouldn't send it to Linus for 2.6.15 just yet though :)
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-15 18:52:18 +00:00
|
|
|
set_thread_flag(TIF_RESTOREALL);
|
2005-04-16 22:20:36 +00:00
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Do a signal return; undo the signal stack.
|
|
|
|
*/
|
|
|
|
|
|
|
|
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 __user *uc = (struct ucontext __user *)regs->gpr[1];
|
|
|
|
sigset_t set;
|
|
|
|
|
|
|
|
/* Always make any pending restarted system calls return -EINTR */
|
|
|
|
current_thread_info()->restart_block.fn = do_no_restart_syscall;
|
|
|
|
|
|
|
|
if (!access_ok(VERIFY_READ, uc, sizeof(*uc)))
|
|
|
|
goto badframe;
|
|
|
|
|
|
|
|
if (__copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
|
|
|
|
goto badframe;
|
|
|
|
restore_sigmask(&set);
|
|
|
|
if (restore_sigcontext(regs, NULL, 1, &uc->uc_mcontext))
|
|
|
|
goto badframe;
|
|
|
|
|
|
|
|
/* do_sigaltstack expects a __user pointer and won't modify
|
|
|
|
* what's in there anyway
|
|
|
|
*/
|
|
|
|
do_sigaltstack(&uc->uc_stack, NULL, regs->gpr[1]);
|
|
|
|
|
[PATCH] syscall entry/exit revamp
This cleanup patch speeds up the null syscall path on ppc64 by about 3%,
and brings the ppc32 and ppc64 code slightly closer together.
The ppc64 code was checking current_thread_info()->flags twice in the
syscall exit path; once for TIF_SYSCALL_T_OR_A before disabling
interrupts, and then again for TIF_SIGPENDING|TIF_NEED_RESCHED etc after
disabling interrupts. Now we do the same as ppc32 -- check the flags
only once in the fast path, and re-enable interrupts if necessary in the
ptrace case.
The patch abolishes the 'syscall_noerror' member of struct thread_info
and replaces it with a TIF_NOERROR bit in the flags, which is handled in
the slow path. This shortens the syscall entry code, which no longer
needs to clear syscall_noerror.
The patch adds a TIF_SAVE_NVGPRS flag which causes the syscall exit slow
path to save the non-volatile GPRs into a signal frame. This removes the
need for the assembly wrappers around sys_sigsuspend(),
sys_rt_sigsuspend(), et al which existed solely to save those registers
in advance. It also means I don't have to add new wrappers for ppoll()
and pselect(), which is what I was supposed to be doing when I got
distracted into this...
Finally, it unifies the ppc64 and ppc32 methods of handling syscall exit
directly into a signal handler (as required by sigsuspend et al) by
introducing a TIF_RESTOREALL flag which causes _all_ the registers to be
reloaded from the pt_regs by taking the ret_from_exception path, instead
of the normal syscall exit path which stomps on the callee-saved GPRs.
It appears to pass an LTP test run on ppc64, and passes basic testing on
ppc32 too. Brief tests of ptrace functionality with strace and gdb also
appear OK. I wouldn't send it to Linus for 2.6.15 just yet though :)
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-15 18:52:18 +00:00
|
|
|
set_thread_flag(TIF_RESTOREALL);
|
|
|
|
return 0;
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
badframe:
|
|
|
|
#if DEBUG_SIG
|
|
|
|
printk("badframe in sys_rt_sigreturn, regs=%p uc=%p &uc->uc_mcontext=%p\n",
|
|
|
|
regs, uc, &uc->uc_mcontext);
|
|
|
|
#endif
|
2007-10-12 00:20:07 +00:00
|
|
|
if (show_unhandled_signals && printk_ratelimit())
|
|
|
|
printk(regs->msr & MSR_SF ? fmt64 : fmt32,
|
|
|
|
current->comm, current->pid, "rt_sigreturn",
|
|
|
|
(long)uc, regs->nip, regs->link);
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
force_sig(SIGSEGV, current);
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2007-06-04 05:15:52 +00:00
|
|
|
int handle_rt_signal64(int signr, struct k_sigaction *ka, siginfo_t *info,
|
2005-04-16 22:20:36 +00:00
|
|
|
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.
|
|
|
|
*/
|
|
|
|
func_descr_t __user *funct_desc_ptr;
|
|
|
|
struct rt_sigframe __user *frame;
|
|
|
|
unsigned long newsp = 0;
|
|
|
|
long err = 0;
|
|
|
|
|
|
|
|
frame = get_sigframe(ka, regs, sizeof(*frame));
|
2007-06-04 07:22:48 +00:00
|
|
|
if (unlikely(frame == NULL))
|
2005-04-16 22:20:36 +00:00
|
|
|
goto badframe;
|
|
|
|
|
|
|
|
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 badframe;
|
|
|
|
|
|
|
|
/* 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 badframe;
|
|
|
|
|
2005-11-14 10:55:15 +00:00
|
|
|
/* Make sure signal handler doesn't get spurious FP exceptions */
|
|
|
|
current->thread.fpscr.val = 0;
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
/* Set up to return from userspace. */
|
2006-05-30 03:51:37 +00:00
|
|
|
if (vdso64_rt_sigtramp && current->mm->context.vdso_base) {
|
|
|
|
regs->link = current->mm->context.vdso_base + vdso64_rt_sigtramp;
|
2005-04-16 22:20:36 +00:00
|
|
|
} else {
|
|
|
|
err |= setup_trampoline(__NR_rt_sigreturn, &frame->tramp[0]);
|
|
|
|
if (err)
|
|
|
|
goto badframe;
|
|
|
|
regs->link = (unsigned long) &frame->tramp[0];
|
|
|
|
}
|
|
|
|
funct_desc_ptr = (func_descr_t __user *) ka->sa.sa_handler;
|
|
|
|
|
|
|
|
/* Allocate a dummy caller frame for the signal handler. */
|
2007-06-04 07:22:48 +00:00
|
|
|
newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
|
2005-04-16 22:20:36 +00:00
|
|
|
err |= put_user(regs->gpr[1], (unsigned long __user *)newsp);
|
|
|
|
|
|
|
|
/* Set up "regs" so we "return" to the signal handler. */
|
|
|
|
err |= get_user(regs->nip, &funct_desc_ptr->entry);
|
2006-06-07 06:14:40 +00:00
|
|
|
/* enter the signal handler in big-endian mode */
|
|
|
|
regs->msr &= ~MSR_LE;
|
2005-04-16 22:20:36 +00:00
|
|
|
regs->gpr[1] = newsp;
|
|
|
|
err |= get_user(regs->gpr[2], &funct_desc_ptr->toc);
|
|
|
|
regs->gpr[3] = signr;
|
|
|
|
regs->result = 0;
|
|
|
|
if (ka->sa.sa_flags & SA_SIGINFO) {
|
|
|
|
err |= get_user(regs->gpr[4], (unsigned long __user *)&frame->pinfo);
|
|
|
|
err |= get_user(regs->gpr[5], (unsigned long __user *)&frame->puc);
|
|
|
|
regs->gpr[6] = (unsigned long) frame;
|
|
|
|
} else {
|
|
|
|
regs->gpr[4] = (unsigned long)&frame->uc.uc_mcontext;
|
|
|
|
}
|
|
|
|
if (err)
|
|
|
|
goto badframe;
|
|
|
|
|
|
|
|
return 1;
|
|
|
|
|
|
|
|
badframe:
|
|
|
|
#if DEBUG_SIG
|
|
|
|
printk("badframe in setup_rt_frame, regs=%p frame=%p newsp=%lx\n",
|
|
|
|
regs, frame, newsp);
|
|
|
|
#endif
|
2007-10-12 00:20:07 +00:00
|
|
|
if (show_unhandled_signals && printk_ratelimit())
|
|
|
|
printk(regs->msr & MSR_SF ? fmt64 : fmt32,
|
|
|
|
current->comm, current->pid, "setup_rt_frame",
|
|
|
|
(long)frame, regs->nip, regs->link);
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
force_sigsegv(signr, current);
|
|
|
|
return 0;
|
|
|
|
}
|