1185 lines
28 KiB
C
1185 lines
28 KiB
C
/*
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* Derived from "arch/i386/kernel/process.c"
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* Copyright (C) 1995 Linus Torvalds
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*
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* Updated and modified by Cort Dougan (cort@cs.nmt.edu) and
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* Paul Mackerras (paulus@cs.anu.edu.au)
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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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* 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/errno.h>
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#include <linux/sched.h>
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#include <linux/kernel.h>
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#include <linux/mm.h>
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#include <linux/smp.h>
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#include <linux/stddef.h>
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#include <linux/unistd.h>
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#include <linux/ptrace.h>
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#include <linux/slab.h>
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#include <linux/user.h>
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#include <linux/elf.h>
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#include <linux/init.h>
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#include <linux/prctl.h>
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#include <linux/init_task.h>
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#include <linux/module.h>
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#include <linux/kallsyms.h>
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#include <linux/mqueue.h>
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#include <linux/hardirq.h>
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#include <linux/utsname.h>
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#include <linux/ftrace.h>
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#include <linux/kernel_stat.h>
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#include <linux/personality.h>
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#include <linux/random.h>
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#include <asm/pgtable.h>
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#include <asm/uaccess.h>
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#include <asm/system.h>
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#include <asm/io.h>
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#include <asm/processor.h>
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#include <asm/mmu.h>
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#include <asm/prom.h>
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#include <asm/machdep.h>
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#include <asm/time.h>
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#include <asm/syscalls.h>
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#ifdef CONFIG_PPC64
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#include <asm/firmware.h>
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#endif
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#include <linux/kprobes.h>
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#include <linux/kdebug.h>
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extern unsigned long _get_SP(void);
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#ifndef CONFIG_SMP
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struct task_struct *last_task_used_math = NULL;
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struct task_struct *last_task_used_altivec = NULL;
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struct task_struct *last_task_used_vsx = NULL;
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struct task_struct *last_task_used_spe = NULL;
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#endif
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/*
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* Make sure the floating-point register state in the
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* the thread_struct is up to date for task tsk.
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*/
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void flush_fp_to_thread(struct task_struct *tsk)
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{
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if (tsk->thread.regs) {
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/*
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* We need to disable preemption here because if we didn't,
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* another process could get scheduled after the regs->msr
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* test but before we have finished saving the FP registers
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* to the thread_struct. That process could take over the
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* FPU, and then when we get scheduled again we would store
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* bogus values for the remaining FP registers.
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*/
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preempt_disable();
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if (tsk->thread.regs->msr & MSR_FP) {
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#ifdef CONFIG_SMP
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/*
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* This should only ever be called for current or
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* for a stopped child process. Since we save away
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* the FP register state on context switch on SMP,
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* there is something wrong if a stopped child appears
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* to still have its FP state in the CPU registers.
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*/
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BUG_ON(tsk != current);
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#endif
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giveup_fpu(tsk);
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}
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preempt_enable();
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}
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}
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void enable_kernel_fp(void)
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{
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WARN_ON(preemptible());
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#ifdef CONFIG_SMP
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if (current->thread.regs && (current->thread.regs->msr & MSR_FP))
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giveup_fpu(current);
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else
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giveup_fpu(NULL); /* just enables FP for kernel */
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#else
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giveup_fpu(last_task_used_math);
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#endif /* CONFIG_SMP */
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}
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EXPORT_SYMBOL(enable_kernel_fp);
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#ifdef CONFIG_ALTIVEC
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void enable_kernel_altivec(void)
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{
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WARN_ON(preemptible());
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#ifdef CONFIG_SMP
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if (current->thread.regs && (current->thread.regs->msr & MSR_VEC))
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giveup_altivec(current);
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else
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giveup_altivec(NULL); /* just enable AltiVec for kernel - force */
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#else
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giveup_altivec(last_task_used_altivec);
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#endif /* CONFIG_SMP */
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}
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EXPORT_SYMBOL(enable_kernel_altivec);
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/*
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* Make sure the VMX/Altivec register state in the
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* the thread_struct is up to date for task tsk.
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*/
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void flush_altivec_to_thread(struct task_struct *tsk)
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{
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if (tsk->thread.regs) {
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preempt_disable();
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if (tsk->thread.regs->msr & MSR_VEC) {
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#ifdef CONFIG_SMP
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BUG_ON(tsk != current);
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#endif
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giveup_altivec(tsk);
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}
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preempt_enable();
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}
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}
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#endif /* CONFIG_ALTIVEC */
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#ifdef CONFIG_VSX
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#if 0
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/* not currently used, but some crazy RAID module might want to later */
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void enable_kernel_vsx(void)
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{
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WARN_ON(preemptible());
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#ifdef CONFIG_SMP
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if (current->thread.regs && (current->thread.regs->msr & MSR_VSX))
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giveup_vsx(current);
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else
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giveup_vsx(NULL); /* just enable vsx for kernel - force */
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#else
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giveup_vsx(last_task_used_vsx);
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#endif /* CONFIG_SMP */
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}
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EXPORT_SYMBOL(enable_kernel_vsx);
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#endif
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void giveup_vsx(struct task_struct *tsk)
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{
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giveup_fpu(tsk);
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giveup_altivec(tsk);
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__giveup_vsx(tsk);
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}
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void flush_vsx_to_thread(struct task_struct *tsk)
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{
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if (tsk->thread.regs) {
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preempt_disable();
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if (tsk->thread.regs->msr & MSR_VSX) {
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#ifdef CONFIG_SMP
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BUG_ON(tsk != current);
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#endif
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giveup_vsx(tsk);
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}
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preempt_enable();
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}
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}
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#endif /* CONFIG_VSX */
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#ifdef CONFIG_SPE
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void enable_kernel_spe(void)
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{
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WARN_ON(preemptible());
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#ifdef CONFIG_SMP
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if (current->thread.regs && (current->thread.regs->msr & MSR_SPE))
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giveup_spe(current);
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else
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giveup_spe(NULL); /* just enable SPE for kernel - force */
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#else
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giveup_spe(last_task_used_spe);
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#endif /* __SMP __ */
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}
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EXPORT_SYMBOL(enable_kernel_spe);
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void flush_spe_to_thread(struct task_struct *tsk)
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{
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if (tsk->thread.regs) {
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preempt_disable();
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if (tsk->thread.regs->msr & MSR_SPE) {
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#ifdef CONFIG_SMP
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BUG_ON(tsk != current);
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#endif
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giveup_spe(tsk);
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}
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preempt_enable();
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}
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}
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#endif /* CONFIG_SPE */
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#ifndef CONFIG_SMP
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/*
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* If we are doing lazy switching of CPU state (FP, altivec or SPE),
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* and the current task has some state, discard it.
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*/
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void discard_lazy_cpu_state(void)
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{
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preempt_disable();
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if (last_task_used_math == current)
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last_task_used_math = NULL;
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#ifdef CONFIG_ALTIVEC
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if (last_task_used_altivec == current)
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last_task_used_altivec = NULL;
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#endif /* CONFIG_ALTIVEC */
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#ifdef CONFIG_VSX
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if (last_task_used_vsx == current)
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last_task_used_vsx = NULL;
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#endif /* CONFIG_VSX */
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#ifdef CONFIG_SPE
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if (last_task_used_spe == current)
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last_task_used_spe = NULL;
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#endif
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preempt_enable();
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}
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#endif /* CONFIG_SMP */
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void do_dabr(struct pt_regs *regs, unsigned long address,
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unsigned long error_code)
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{
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siginfo_t info;
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if (notify_die(DIE_DABR_MATCH, "dabr_match", regs, error_code,
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11, SIGSEGV) == NOTIFY_STOP)
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return;
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if (debugger_dabr_match(regs))
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return;
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/* Clear the DAC and struct entries. One shot trigger */
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#if defined(CONFIG_BOOKE)
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mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) & ~(DBSR_DAC1R | DBSR_DAC1W
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| DBCR0_IDM));
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#endif
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/* Clear the DABR */
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set_dabr(0);
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/* Deliver the signal to userspace */
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info.si_signo = SIGTRAP;
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info.si_errno = 0;
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info.si_code = TRAP_HWBKPT;
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info.si_addr = (void __user *)address;
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force_sig_info(SIGTRAP, &info, current);
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}
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static DEFINE_PER_CPU(unsigned long, current_dabr);
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int set_dabr(unsigned long dabr)
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{
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__get_cpu_var(current_dabr) = dabr;
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if (ppc_md.set_dabr)
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return ppc_md.set_dabr(dabr);
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/* XXX should we have a CPU_FTR_HAS_DABR ? */
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#if defined(CONFIG_PPC64) || defined(CONFIG_6xx)
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mtspr(SPRN_DABR, dabr);
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#endif
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#if defined(CONFIG_BOOKE)
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mtspr(SPRN_DAC1, dabr);
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#endif
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return 0;
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}
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#ifdef CONFIG_PPC64
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DEFINE_PER_CPU(struct cpu_usage, cpu_usage_array);
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#endif
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struct task_struct *__switch_to(struct task_struct *prev,
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struct task_struct *new)
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{
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struct thread_struct *new_thread, *old_thread;
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unsigned long flags;
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struct task_struct *last;
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#ifdef CONFIG_SMP
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/* avoid complexity of lazy save/restore of fpu
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* by just saving it every time we switch out if
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* this task used the fpu during the last quantum.
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*
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* If it tries to use the fpu again, it'll trap and
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* reload its fp regs. So we don't have to do a restore
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* every switch, just a save.
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* -- Cort
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*/
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if (prev->thread.regs && (prev->thread.regs->msr & MSR_FP))
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giveup_fpu(prev);
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#ifdef CONFIG_ALTIVEC
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/*
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* If the previous thread used altivec in the last quantum
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* (thus changing altivec regs) then save them.
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* We used to check the VRSAVE register but not all apps
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* set it, so we don't rely on it now (and in fact we need
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* to save & restore VSCR even if VRSAVE == 0). -- paulus
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*
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* On SMP we always save/restore altivec regs just to avoid the
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* complexity of changing processors.
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* -- Cort
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*/
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if (prev->thread.regs && (prev->thread.regs->msr & MSR_VEC))
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giveup_altivec(prev);
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#endif /* CONFIG_ALTIVEC */
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#ifdef CONFIG_VSX
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if (prev->thread.regs && (prev->thread.regs->msr & MSR_VSX))
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/* VMX and FPU registers are already save here */
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__giveup_vsx(prev);
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#endif /* CONFIG_VSX */
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#ifdef CONFIG_SPE
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/*
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* If the previous thread used spe in the last quantum
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* (thus changing spe regs) then save them.
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*
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* On SMP we always save/restore spe regs just to avoid the
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* complexity of changing processors.
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*/
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if ((prev->thread.regs && (prev->thread.regs->msr & MSR_SPE)))
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giveup_spe(prev);
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#endif /* CONFIG_SPE */
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#else /* CONFIG_SMP */
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#ifdef CONFIG_ALTIVEC
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/* Avoid the trap. On smp this this never happens since
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* we don't set last_task_used_altivec -- Cort
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*/
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if (new->thread.regs && last_task_used_altivec == new)
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new->thread.regs->msr |= MSR_VEC;
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#endif /* CONFIG_ALTIVEC */
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#ifdef CONFIG_VSX
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if (new->thread.regs && last_task_used_vsx == new)
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new->thread.regs->msr |= MSR_VSX;
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#endif /* CONFIG_VSX */
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#ifdef CONFIG_SPE
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/* Avoid the trap. On smp this this never happens since
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* we don't set last_task_used_spe
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*/
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if (new->thread.regs && last_task_used_spe == new)
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new->thread.regs->msr |= MSR_SPE;
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#endif /* CONFIG_SPE */
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#endif /* CONFIG_SMP */
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if (unlikely(__get_cpu_var(current_dabr) != new->thread.dabr))
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set_dabr(new->thread.dabr);
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#if defined(CONFIG_BOOKE)
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/* If new thread DAC (HW breakpoint) is the same then leave it */
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if (new->thread.dabr)
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set_dabr(new->thread.dabr);
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#endif
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new_thread = &new->thread;
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old_thread = ¤t->thread;
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#ifdef CONFIG_PPC64
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/*
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* Collect processor utilization data per process
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*/
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if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
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struct cpu_usage *cu = &__get_cpu_var(cpu_usage_array);
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long unsigned start_tb, current_tb;
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start_tb = old_thread->start_tb;
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cu->current_tb = current_tb = mfspr(SPRN_PURR);
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old_thread->accum_tb += (current_tb - start_tb);
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new_thread->start_tb = current_tb;
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}
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#endif
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local_irq_save(flags);
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account_system_vtime(current);
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account_process_vtime(current);
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calculate_steal_time();
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/*
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* We can't take a PMU exception inside _switch() since there is a
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* window where the kernel stack SLB and the kernel stack are out
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* of sync. Hard disable here.
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*/
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hard_irq_disable();
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last = _switch(old_thread, new_thread);
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local_irq_restore(flags);
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return last;
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}
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static int instructions_to_print = 16;
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static void show_instructions(struct pt_regs *regs)
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{
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int i;
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unsigned long pc = regs->nip - (instructions_to_print * 3 / 4 *
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sizeof(int));
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printk("Instruction dump:");
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for (i = 0; i < instructions_to_print; i++) {
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int instr;
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if (!(i % 8))
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printk("\n");
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#if !defined(CONFIG_BOOKE)
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/* If executing with the IMMU off, adjust pc rather
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* than print XXXXXXXX.
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*/
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if (!(regs->msr & MSR_IR))
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pc = (unsigned long)phys_to_virt(pc);
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#endif
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/* We use __get_user here *only* to avoid an OOPS on a
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* bad address because the pc *should* only be a
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* kernel address.
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*/
|
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if (!__kernel_text_address(pc) ||
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__get_user(instr, (unsigned int __user *)pc)) {
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printk("XXXXXXXX ");
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} else {
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if (regs->nip == pc)
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printk("<%08x> ", instr);
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else
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printk("%08x ", instr);
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}
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pc += sizeof(int);
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}
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printk("\n");
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}
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|
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static struct regbit {
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unsigned long bit;
|
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const char *name;
|
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} msr_bits[] = {
|
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{MSR_EE, "EE"},
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{MSR_PR, "PR"},
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{MSR_FP, "FP"},
|
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{MSR_VEC, "VEC"},
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{MSR_VSX, "VSX"},
|
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{MSR_ME, "ME"},
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{MSR_CE, "CE"},
|
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{MSR_DE, "DE"},
|
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{MSR_IR, "IR"},
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{MSR_DR, "DR"},
|
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{0, NULL}
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};
|
|
|
|
static void printbits(unsigned long val, struct regbit *bits)
|
|
{
|
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const char *sep = "";
|
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|
|
printk("<");
|
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for (; bits->bit; ++bits)
|
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if (val & bits->bit) {
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printk("%s%s", sep, bits->name);
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sep = ",";
|
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}
|
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printk(">");
|
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}
|
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|
|
#ifdef CONFIG_PPC64
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|
#define REG "%016lx"
|
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#define REGS_PER_LINE 4
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#define LAST_VOLATILE 13
|
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#else
|
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#define REG "%08lx"
|
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#define REGS_PER_LINE 8
|
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#define LAST_VOLATILE 12
|
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#endif
|
|
|
|
void show_regs(struct pt_regs * regs)
|
|
{
|
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int i, trap;
|
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|
|
printk("NIP: "REG" LR: "REG" CTR: "REG"\n",
|
|
regs->nip, regs->link, regs->ctr);
|
|
printk("REGS: %p TRAP: %04lx %s (%s)\n",
|
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regs, regs->trap, print_tainted(), init_utsname()->release);
|
|
printk("MSR: "REG" ", regs->msr);
|
|
printbits(regs->msr, msr_bits);
|
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printk(" CR: %08lx XER: %08lx\n", regs->ccr, regs->xer);
|
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trap = TRAP(regs);
|
|
if (trap == 0x300 || trap == 0x600)
|
|
#if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
|
|
printk("DEAR: "REG", ESR: "REG"\n", regs->dar, regs->dsisr);
|
|
#else
|
|
printk("DAR: "REG", DSISR: "REG"\n", regs->dar, regs->dsisr);
|
|
#endif
|
|
printk("TASK = %p[%d] '%s' THREAD: %p",
|
|
current, task_pid_nr(current), current->comm, task_thread_info(current));
|
|
|
|
#ifdef CONFIG_SMP
|
|
printk(" CPU: %d", raw_smp_processor_id());
|
|
#endif /* CONFIG_SMP */
|
|
|
|
for (i = 0; i < 32; i++) {
|
|
if ((i % REGS_PER_LINE) == 0)
|
|
printk("\nGPR%02d: ", i);
|
|
printk(REG " ", regs->gpr[i]);
|
|
if (i == LAST_VOLATILE && !FULL_REGS(regs))
|
|
break;
|
|
}
|
|
printk("\n");
|
|
#ifdef CONFIG_KALLSYMS
|
|
/*
|
|
* Lookup NIP late so we have the best change of getting the
|
|
* above info out without failing
|
|
*/
|
|
printk("NIP ["REG"] %pS\n", regs->nip, (void *)regs->nip);
|
|
printk("LR ["REG"] %pS\n", regs->link, (void *)regs->link);
|
|
#endif
|
|
show_stack(current, (unsigned long *) regs->gpr[1]);
|
|
if (!user_mode(regs))
|
|
show_instructions(regs);
|
|
}
|
|
|
|
void exit_thread(void)
|
|
{
|
|
discard_lazy_cpu_state();
|
|
}
|
|
|
|
void flush_thread(void)
|
|
{
|
|
#ifdef CONFIG_PPC64
|
|
struct thread_info *t = current_thread_info();
|
|
|
|
if (test_ti_thread_flag(t, TIF_ABI_PENDING)) {
|
|
clear_ti_thread_flag(t, TIF_ABI_PENDING);
|
|
if (test_ti_thread_flag(t, TIF_32BIT))
|
|
clear_ti_thread_flag(t, TIF_32BIT);
|
|
else
|
|
set_ti_thread_flag(t, TIF_32BIT);
|
|
}
|
|
#endif
|
|
|
|
discard_lazy_cpu_state();
|
|
|
|
if (current->thread.dabr) {
|
|
current->thread.dabr = 0;
|
|
set_dabr(0);
|
|
|
|
#if defined(CONFIG_BOOKE)
|
|
current->thread.dbcr0 &= ~(DBSR_DAC1R | DBSR_DAC1W);
|
|
#endif
|
|
}
|
|
}
|
|
|
|
void
|
|
release_thread(struct task_struct *t)
|
|
{
|
|
}
|
|
|
|
/*
|
|
* This gets called before we allocate a new thread and copy
|
|
* the current task into it.
|
|
*/
|
|
void prepare_to_copy(struct task_struct *tsk)
|
|
{
|
|
flush_fp_to_thread(current);
|
|
flush_altivec_to_thread(current);
|
|
flush_vsx_to_thread(current);
|
|
flush_spe_to_thread(current);
|
|
}
|
|
|
|
/*
|
|
* Copy a thread..
|
|
*/
|
|
int copy_thread(unsigned long clone_flags, unsigned long usp,
|
|
unsigned long unused, struct task_struct *p,
|
|
struct pt_regs *regs)
|
|
{
|
|
struct pt_regs *childregs, *kregs;
|
|
extern void ret_from_fork(void);
|
|
unsigned long sp = (unsigned long)task_stack_page(p) + THREAD_SIZE;
|
|
|
|
CHECK_FULL_REGS(regs);
|
|
/* Copy registers */
|
|
sp -= sizeof(struct pt_regs);
|
|
childregs = (struct pt_regs *) sp;
|
|
*childregs = *regs;
|
|
if ((childregs->msr & MSR_PR) == 0) {
|
|
/* for kernel thread, set `current' and stackptr in new task */
|
|
childregs->gpr[1] = sp + sizeof(struct pt_regs);
|
|
#ifdef CONFIG_PPC32
|
|
childregs->gpr[2] = (unsigned long) p;
|
|
#else
|
|
clear_tsk_thread_flag(p, TIF_32BIT);
|
|
#endif
|
|
p->thread.regs = NULL; /* no user register state */
|
|
} else {
|
|
childregs->gpr[1] = usp;
|
|
p->thread.regs = childregs;
|
|
if (clone_flags & CLONE_SETTLS) {
|
|
#ifdef CONFIG_PPC64
|
|
if (!test_thread_flag(TIF_32BIT))
|
|
childregs->gpr[13] = childregs->gpr[6];
|
|
else
|
|
#endif
|
|
childregs->gpr[2] = childregs->gpr[6];
|
|
}
|
|
}
|
|
childregs->gpr[3] = 0; /* Result from fork() */
|
|
sp -= STACK_FRAME_OVERHEAD;
|
|
|
|
/*
|
|
* The way this works is that at some point in the future
|
|
* some task will call _switch to switch to the new task.
|
|
* That will pop off the stack frame created below and start
|
|
* the new task running at ret_from_fork. The new task will
|
|
* do some house keeping and then return from the fork or clone
|
|
* system call, using the stack frame created above.
|
|
*/
|
|
sp -= sizeof(struct pt_regs);
|
|
kregs = (struct pt_regs *) sp;
|
|
sp -= STACK_FRAME_OVERHEAD;
|
|
p->thread.ksp = sp;
|
|
p->thread.ksp_limit = (unsigned long)task_stack_page(p) +
|
|
_ALIGN_UP(sizeof(struct thread_info), 16);
|
|
|
|
#ifdef CONFIG_PPC_STD_MMU_64
|
|
if (cpu_has_feature(CPU_FTR_SLB)) {
|
|
unsigned long sp_vsid;
|
|
unsigned long llp = mmu_psize_defs[mmu_linear_psize].sllp;
|
|
|
|
if (cpu_has_feature(CPU_FTR_1T_SEGMENT))
|
|
sp_vsid = get_kernel_vsid(sp, MMU_SEGSIZE_1T)
|
|
<< SLB_VSID_SHIFT_1T;
|
|
else
|
|
sp_vsid = get_kernel_vsid(sp, MMU_SEGSIZE_256M)
|
|
<< SLB_VSID_SHIFT;
|
|
sp_vsid |= SLB_VSID_KERNEL | llp;
|
|
p->thread.ksp_vsid = sp_vsid;
|
|
}
|
|
#endif /* CONFIG_PPC_STD_MMU_64 */
|
|
|
|
/*
|
|
* The PPC64 ABI makes use of a TOC to contain function
|
|
* pointers. The function (ret_from_except) is actually a pointer
|
|
* to the TOC entry. The first entry is a pointer to the actual
|
|
* function.
|
|
*/
|
|
#ifdef CONFIG_PPC64
|
|
kregs->nip = *((unsigned long *)ret_from_fork);
|
|
#else
|
|
kregs->nip = (unsigned long)ret_from_fork;
|
|
#endif
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Set up a thread for executing a new program
|
|
*/
|
|
void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp)
|
|
{
|
|
#ifdef CONFIG_PPC64
|
|
unsigned long load_addr = regs->gpr[2]; /* saved by ELF_PLAT_INIT */
|
|
#endif
|
|
|
|
set_fs(USER_DS);
|
|
|
|
/*
|
|
* If we exec out of a kernel thread then thread.regs will not be
|
|
* set. Do it now.
|
|
*/
|
|
if (!current->thread.regs) {
|
|
struct pt_regs *regs = task_stack_page(current) + THREAD_SIZE;
|
|
current->thread.regs = regs - 1;
|
|
}
|
|
|
|
memset(regs->gpr, 0, sizeof(regs->gpr));
|
|
regs->ctr = 0;
|
|
regs->link = 0;
|
|
regs->xer = 0;
|
|
regs->ccr = 0;
|
|
regs->gpr[1] = sp;
|
|
|
|
/*
|
|
* We have just cleared all the nonvolatile GPRs, so make
|
|
* FULL_REGS(regs) return true. This is necessary to allow
|
|
* ptrace to examine the thread immediately after exec.
|
|
*/
|
|
regs->trap &= ~1UL;
|
|
|
|
#ifdef CONFIG_PPC32
|
|
regs->mq = 0;
|
|
regs->nip = start;
|
|
regs->msr = MSR_USER;
|
|
#else
|
|
if (!test_thread_flag(TIF_32BIT)) {
|
|
unsigned long entry, toc;
|
|
|
|
/* start is a relocated pointer to the function descriptor for
|
|
* the elf _start routine. The first entry in the function
|
|
* descriptor is the entry address of _start and the second
|
|
* entry is the TOC value we need to use.
|
|
*/
|
|
__get_user(entry, (unsigned long __user *)start);
|
|
__get_user(toc, (unsigned long __user *)start+1);
|
|
|
|
/* Check whether the e_entry function descriptor entries
|
|
* need to be relocated before we can use them.
|
|
*/
|
|
if (load_addr != 0) {
|
|
entry += load_addr;
|
|
toc += load_addr;
|
|
}
|
|
regs->nip = entry;
|
|
regs->gpr[2] = toc;
|
|
regs->msr = MSR_USER64;
|
|
} else {
|
|
regs->nip = start;
|
|
regs->gpr[2] = 0;
|
|
regs->msr = MSR_USER32;
|
|
}
|
|
#endif
|
|
|
|
discard_lazy_cpu_state();
|
|
#ifdef CONFIG_VSX
|
|
current->thread.used_vsr = 0;
|
|
#endif
|
|
memset(current->thread.fpr, 0, sizeof(current->thread.fpr));
|
|
current->thread.fpscr.val = 0;
|
|
#ifdef CONFIG_ALTIVEC
|
|
memset(current->thread.vr, 0, sizeof(current->thread.vr));
|
|
memset(¤t->thread.vscr, 0, sizeof(current->thread.vscr));
|
|
current->thread.vscr.u[3] = 0x00010000; /* Java mode disabled */
|
|
current->thread.vrsave = 0;
|
|
current->thread.used_vr = 0;
|
|
#endif /* CONFIG_ALTIVEC */
|
|
#ifdef CONFIG_SPE
|
|
memset(current->thread.evr, 0, sizeof(current->thread.evr));
|
|
current->thread.acc = 0;
|
|
current->thread.spefscr = 0;
|
|
current->thread.used_spe = 0;
|
|
#endif /* CONFIG_SPE */
|
|
}
|
|
|
|
#define PR_FP_ALL_EXCEPT (PR_FP_EXC_DIV | PR_FP_EXC_OVF | PR_FP_EXC_UND \
|
|
| PR_FP_EXC_RES | PR_FP_EXC_INV)
|
|
|
|
int set_fpexc_mode(struct task_struct *tsk, unsigned int val)
|
|
{
|
|
struct pt_regs *regs = tsk->thread.regs;
|
|
|
|
/* This is a bit hairy. If we are an SPE enabled processor
|
|
* (have embedded fp) we store the IEEE exception enable flags in
|
|
* fpexc_mode. fpexc_mode is also used for setting FP exception
|
|
* mode (asyn, precise, disabled) for 'Classic' FP. */
|
|
if (val & PR_FP_EXC_SW_ENABLE) {
|
|
#ifdef CONFIG_SPE
|
|
if (cpu_has_feature(CPU_FTR_SPE)) {
|
|
tsk->thread.fpexc_mode = val &
|
|
(PR_FP_EXC_SW_ENABLE | PR_FP_ALL_EXCEPT);
|
|
return 0;
|
|
} else {
|
|
return -EINVAL;
|
|
}
|
|
#else
|
|
return -EINVAL;
|
|
#endif
|
|
}
|
|
|
|
/* on a CONFIG_SPE this does not hurt us. The bits that
|
|
* __pack_fe01 use do not overlap with bits used for
|
|
* PR_FP_EXC_SW_ENABLE. Additionally, the MSR[FE0,FE1] bits
|
|
* on CONFIG_SPE implementations are reserved so writing to
|
|
* them does not change anything */
|
|
if (val > PR_FP_EXC_PRECISE)
|
|
return -EINVAL;
|
|
tsk->thread.fpexc_mode = __pack_fe01(val);
|
|
if (regs != NULL && (regs->msr & MSR_FP) != 0)
|
|
regs->msr = (regs->msr & ~(MSR_FE0|MSR_FE1))
|
|
| tsk->thread.fpexc_mode;
|
|
return 0;
|
|
}
|
|
|
|
int get_fpexc_mode(struct task_struct *tsk, unsigned long adr)
|
|
{
|
|
unsigned int val;
|
|
|
|
if (tsk->thread.fpexc_mode & PR_FP_EXC_SW_ENABLE)
|
|
#ifdef CONFIG_SPE
|
|
if (cpu_has_feature(CPU_FTR_SPE))
|
|
val = tsk->thread.fpexc_mode;
|
|
else
|
|
return -EINVAL;
|
|
#else
|
|
return -EINVAL;
|
|
#endif
|
|
else
|
|
val = __unpack_fe01(tsk->thread.fpexc_mode);
|
|
return put_user(val, (unsigned int __user *) adr);
|
|
}
|
|
|
|
int set_endian(struct task_struct *tsk, unsigned int val)
|
|
{
|
|
struct pt_regs *regs = tsk->thread.regs;
|
|
|
|
if ((val == PR_ENDIAN_LITTLE && !cpu_has_feature(CPU_FTR_REAL_LE)) ||
|
|
(val == PR_ENDIAN_PPC_LITTLE && !cpu_has_feature(CPU_FTR_PPC_LE)))
|
|
return -EINVAL;
|
|
|
|
if (regs == NULL)
|
|
return -EINVAL;
|
|
|
|
if (val == PR_ENDIAN_BIG)
|
|
regs->msr &= ~MSR_LE;
|
|
else if (val == PR_ENDIAN_LITTLE || val == PR_ENDIAN_PPC_LITTLE)
|
|
regs->msr |= MSR_LE;
|
|
else
|
|
return -EINVAL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int get_endian(struct task_struct *tsk, unsigned long adr)
|
|
{
|
|
struct pt_regs *regs = tsk->thread.regs;
|
|
unsigned int val;
|
|
|
|
if (!cpu_has_feature(CPU_FTR_PPC_LE) &&
|
|
!cpu_has_feature(CPU_FTR_REAL_LE))
|
|
return -EINVAL;
|
|
|
|
if (regs == NULL)
|
|
return -EINVAL;
|
|
|
|
if (regs->msr & MSR_LE) {
|
|
if (cpu_has_feature(CPU_FTR_REAL_LE))
|
|
val = PR_ENDIAN_LITTLE;
|
|
else
|
|
val = PR_ENDIAN_PPC_LITTLE;
|
|
} else
|
|
val = PR_ENDIAN_BIG;
|
|
|
|
return put_user(val, (unsigned int __user *)adr);
|
|
}
|
|
|
|
int set_unalign_ctl(struct task_struct *tsk, unsigned int val)
|
|
{
|
|
tsk->thread.align_ctl = val;
|
|
return 0;
|
|
}
|
|
|
|
int get_unalign_ctl(struct task_struct *tsk, unsigned long adr)
|
|
{
|
|
return put_user(tsk->thread.align_ctl, (unsigned int __user *)adr);
|
|
}
|
|
|
|
#define TRUNC_PTR(x) ((typeof(x))(((unsigned long)(x)) & 0xffffffff))
|
|
|
|
int sys_clone(unsigned long clone_flags, unsigned long usp,
|
|
int __user *parent_tidp, void __user *child_threadptr,
|
|
int __user *child_tidp, int p6,
|
|
struct pt_regs *regs)
|
|
{
|
|
CHECK_FULL_REGS(regs);
|
|
if (usp == 0)
|
|
usp = regs->gpr[1]; /* stack pointer for child */
|
|
#ifdef CONFIG_PPC64
|
|
if (test_thread_flag(TIF_32BIT)) {
|
|
parent_tidp = TRUNC_PTR(parent_tidp);
|
|
child_tidp = TRUNC_PTR(child_tidp);
|
|
}
|
|
#endif
|
|
return do_fork(clone_flags, usp, regs, 0, parent_tidp, child_tidp);
|
|
}
|
|
|
|
int sys_fork(unsigned long p1, unsigned long p2, unsigned long p3,
|
|
unsigned long p4, unsigned long p5, unsigned long p6,
|
|
struct pt_regs *regs)
|
|
{
|
|
CHECK_FULL_REGS(regs);
|
|
return do_fork(SIGCHLD, regs->gpr[1], regs, 0, NULL, NULL);
|
|
}
|
|
|
|
int sys_vfork(unsigned long p1, unsigned long p2, unsigned long p3,
|
|
unsigned long p4, unsigned long p5, unsigned long p6,
|
|
struct pt_regs *regs)
|
|
{
|
|
CHECK_FULL_REGS(regs);
|
|
return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->gpr[1],
|
|
regs, 0, NULL, NULL);
|
|
}
|
|
|
|
int sys_execve(unsigned long a0, unsigned long a1, unsigned long a2,
|
|
unsigned long a3, unsigned long a4, unsigned long a5,
|
|
struct pt_regs *regs)
|
|
{
|
|
int error;
|
|
char *filename;
|
|
|
|
filename = getname((char __user *) a0);
|
|
error = PTR_ERR(filename);
|
|
if (IS_ERR(filename))
|
|
goto out;
|
|
flush_fp_to_thread(current);
|
|
flush_altivec_to_thread(current);
|
|
flush_spe_to_thread(current);
|
|
error = do_execve(filename, (char __user * __user *) a1,
|
|
(char __user * __user *) a2, regs);
|
|
putname(filename);
|
|
out:
|
|
return error;
|
|
}
|
|
|
|
#ifdef CONFIG_IRQSTACKS
|
|
static inline int valid_irq_stack(unsigned long sp, struct task_struct *p,
|
|
unsigned long nbytes)
|
|
{
|
|
unsigned long stack_page;
|
|
unsigned long cpu = task_cpu(p);
|
|
|
|
/*
|
|
* Avoid crashing if the stack has overflowed and corrupted
|
|
* task_cpu(p), which is in the thread_info struct.
|
|
*/
|
|
if (cpu < NR_CPUS && cpu_possible(cpu)) {
|
|
stack_page = (unsigned long) hardirq_ctx[cpu];
|
|
if (sp >= stack_page + sizeof(struct thread_struct)
|
|
&& sp <= stack_page + THREAD_SIZE - nbytes)
|
|
return 1;
|
|
|
|
stack_page = (unsigned long) softirq_ctx[cpu];
|
|
if (sp >= stack_page + sizeof(struct thread_struct)
|
|
&& sp <= stack_page + THREAD_SIZE - nbytes)
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
#else
|
|
#define valid_irq_stack(sp, p, nb) 0
|
|
#endif /* CONFIG_IRQSTACKS */
|
|
|
|
int validate_sp(unsigned long sp, struct task_struct *p,
|
|
unsigned long nbytes)
|
|
{
|
|
unsigned long stack_page = (unsigned long)task_stack_page(p);
|
|
|
|
if (sp >= stack_page + sizeof(struct thread_struct)
|
|
&& sp <= stack_page + THREAD_SIZE - nbytes)
|
|
return 1;
|
|
|
|
return valid_irq_stack(sp, p, nbytes);
|
|
}
|
|
|
|
EXPORT_SYMBOL(validate_sp);
|
|
|
|
unsigned long get_wchan(struct task_struct *p)
|
|
{
|
|
unsigned long ip, sp;
|
|
int count = 0;
|
|
|
|
if (!p || p == current || p->state == TASK_RUNNING)
|
|
return 0;
|
|
|
|
sp = p->thread.ksp;
|
|
if (!validate_sp(sp, p, STACK_FRAME_OVERHEAD))
|
|
return 0;
|
|
|
|
do {
|
|
sp = *(unsigned long *)sp;
|
|
if (!validate_sp(sp, p, STACK_FRAME_OVERHEAD))
|
|
return 0;
|
|
if (count > 0) {
|
|
ip = ((unsigned long *)sp)[STACK_FRAME_LR_SAVE];
|
|
if (!in_sched_functions(ip))
|
|
return ip;
|
|
}
|
|
} while (count++ < 16);
|
|
return 0;
|
|
}
|
|
|
|
static int kstack_depth_to_print = CONFIG_PRINT_STACK_DEPTH;
|
|
|
|
void show_stack(struct task_struct *tsk, unsigned long *stack)
|
|
{
|
|
unsigned long sp, ip, lr, newsp;
|
|
int count = 0;
|
|
int firstframe = 1;
|
|
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
|
|
int curr_frame = current->curr_ret_stack;
|
|
extern void return_to_handler(void);
|
|
unsigned long addr = (unsigned long)return_to_handler;
|
|
#ifdef CONFIG_PPC64
|
|
addr = *(unsigned long*)addr;
|
|
#endif
|
|
#endif
|
|
|
|
sp = (unsigned long) stack;
|
|
if (tsk == NULL)
|
|
tsk = current;
|
|
if (sp == 0) {
|
|
if (tsk == current)
|
|
asm("mr %0,1" : "=r" (sp));
|
|
else
|
|
sp = tsk->thread.ksp;
|
|
}
|
|
|
|
lr = 0;
|
|
printk("Call Trace:\n");
|
|
do {
|
|
if (!validate_sp(sp, tsk, STACK_FRAME_OVERHEAD))
|
|
return;
|
|
|
|
stack = (unsigned long *) sp;
|
|
newsp = stack[0];
|
|
ip = stack[STACK_FRAME_LR_SAVE];
|
|
if (!firstframe || ip != lr) {
|
|
printk("["REG"] ["REG"] %pS", sp, ip, (void *)ip);
|
|
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
|
|
if (ip == addr && curr_frame >= 0) {
|
|
printk(" (%pS)",
|
|
(void *)current->ret_stack[curr_frame].ret);
|
|
curr_frame--;
|
|
}
|
|
#endif
|
|
if (firstframe)
|
|
printk(" (unreliable)");
|
|
printk("\n");
|
|
}
|
|
firstframe = 0;
|
|
|
|
/*
|
|
* See if this is an exception frame.
|
|
* We look for the "regshere" marker in the current frame.
|
|
*/
|
|
if (validate_sp(sp, tsk, STACK_INT_FRAME_SIZE)
|
|
&& stack[STACK_FRAME_MARKER] == STACK_FRAME_REGS_MARKER) {
|
|
struct pt_regs *regs = (struct pt_regs *)
|
|
(sp + STACK_FRAME_OVERHEAD);
|
|
lr = regs->link;
|
|
printk("--- Exception: %lx at %pS\n LR = %pS\n",
|
|
regs->trap, (void *)regs->nip, (void *)lr);
|
|
firstframe = 1;
|
|
}
|
|
|
|
sp = newsp;
|
|
} while (count++ < kstack_depth_to_print);
|
|
}
|
|
|
|
void dump_stack(void)
|
|
{
|
|
show_stack(current, NULL);
|
|
}
|
|
EXPORT_SYMBOL(dump_stack);
|
|
|
|
#ifdef CONFIG_PPC64
|
|
void ppc64_runlatch_on(void)
|
|
{
|
|
unsigned long ctrl;
|
|
|
|
if (cpu_has_feature(CPU_FTR_CTRL) && !test_thread_flag(TIF_RUNLATCH)) {
|
|
HMT_medium();
|
|
|
|
ctrl = mfspr(SPRN_CTRLF);
|
|
ctrl |= CTRL_RUNLATCH;
|
|
mtspr(SPRN_CTRLT, ctrl);
|
|
|
|
set_thread_flag(TIF_RUNLATCH);
|
|
}
|
|
}
|
|
|
|
void ppc64_runlatch_off(void)
|
|
{
|
|
unsigned long ctrl;
|
|
|
|
if (cpu_has_feature(CPU_FTR_CTRL) && test_thread_flag(TIF_RUNLATCH)) {
|
|
HMT_medium();
|
|
|
|
clear_thread_flag(TIF_RUNLATCH);
|
|
|
|
ctrl = mfspr(SPRN_CTRLF);
|
|
ctrl &= ~CTRL_RUNLATCH;
|
|
mtspr(SPRN_CTRLT, ctrl);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
#if THREAD_SHIFT < PAGE_SHIFT
|
|
|
|
static struct kmem_cache *thread_info_cache;
|
|
|
|
struct thread_info *alloc_thread_info(struct task_struct *tsk)
|
|
{
|
|
struct thread_info *ti;
|
|
|
|
ti = kmem_cache_alloc(thread_info_cache, GFP_KERNEL);
|
|
if (unlikely(ti == NULL))
|
|
return NULL;
|
|
#ifdef CONFIG_DEBUG_STACK_USAGE
|
|
memset(ti, 0, THREAD_SIZE);
|
|
#endif
|
|
return ti;
|
|
}
|
|
|
|
void free_thread_info(struct thread_info *ti)
|
|
{
|
|
kmem_cache_free(thread_info_cache, ti);
|
|
}
|
|
|
|
void thread_info_cache_init(void)
|
|
{
|
|
thread_info_cache = kmem_cache_create("thread_info", THREAD_SIZE,
|
|
THREAD_SIZE, 0, NULL);
|
|
BUG_ON(thread_info_cache == NULL);
|
|
}
|
|
|
|
#endif /* THREAD_SHIFT < PAGE_SHIFT */
|
|
|
|
unsigned long arch_align_stack(unsigned long sp)
|
|
{
|
|
if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
|
|
sp -= get_random_int() & ~PAGE_MASK;
|
|
return sp & ~0xf;
|
|
}
|
|
|
|
static inline unsigned long brk_rnd(void)
|
|
{
|
|
unsigned long rnd = 0;
|
|
|
|
/* 8MB for 32bit, 1GB for 64bit */
|
|
if (is_32bit_task())
|
|
rnd = (long)(get_random_int() % (1<<(23-PAGE_SHIFT)));
|
|
else
|
|
rnd = (long)(get_random_int() % (1<<(30-PAGE_SHIFT)));
|
|
|
|
return rnd << PAGE_SHIFT;
|
|
}
|
|
|
|
unsigned long arch_randomize_brk(struct mm_struct *mm)
|
|
{
|
|
unsigned long ret = PAGE_ALIGN(mm->brk + brk_rnd());
|
|
|
|
if (ret < mm->brk)
|
|
return mm->brk;
|
|
|
|
return ret;
|
|
}
|
|
|
|
unsigned long randomize_et_dyn(unsigned long base)
|
|
{
|
|
unsigned long ret = PAGE_ALIGN(base + brk_rnd());
|
|
|
|
if (ret < base)
|
|
return base;
|
|
|
|
return ret;
|
|
}
|