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https://github.com/AuxXxilium/linux_dsm_epyc7002.git
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829023df86
Currently tm_orig_msr is getting used during process context switch only. Then there is ckpt_regs which saves the checkpointed userspace context The MSR slot contained in ckpt_regs structure can be used during process context switch instead of tm_orig_msr, thus allowing us to drop it from thread_struct structure. This patch does that change. Acked-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
1661 lines
43 KiB
C
1661 lines
43 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/prctl.h>
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#include <linux/init_task.h>
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#include <linux/export.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 <linux/hw_breakpoint.h>
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#include <linux/uaccess.h>
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#include <asm/pgtable.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/runlatch.h>
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#include <asm/syscalls.h>
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#include <asm/switch_to.h>
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#include <asm/tm.h>
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#include <asm/debug.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 <asm/code-patching.h>
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#include <linux/kprobes.h>
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#include <linux/kdebug.h>
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/* Transactional Memory debug */
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#ifdef TM_DEBUG_SW
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#define TM_DEBUG(x...) printk(KERN_INFO x)
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#else
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#define TM_DEBUG(x...) do { } while(0)
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#endif
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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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#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
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void giveup_fpu_maybe_transactional(struct task_struct *tsk)
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{
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/*
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* If we are saving the current thread's registers, and the
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* thread is in a transactional state, set the TIF_RESTORE_TM
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* bit so that we know to restore the registers before
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* returning to userspace.
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*/
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if (tsk == current && tsk->thread.regs &&
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MSR_TM_ACTIVE(tsk->thread.regs->msr) &&
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!test_thread_flag(TIF_RESTORE_TM)) {
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tsk->thread.ckpt_regs.msr = tsk->thread.regs->msr;
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set_thread_flag(TIF_RESTORE_TM);
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}
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giveup_fpu(tsk);
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}
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void giveup_altivec_maybe_transactional(struct task_struct *tsk)
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{
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/*
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* If we are saving the current thread's registers, and the
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* thread is in a transactional state, set the TIF_RESTORE_TM
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* bit so that we know to restore the registers before
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* returning to userspace.
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*/
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if (tsk == current && tsk->thread.regs &&
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MSR_TM_ACTIVE(tsk->thread.regs->msr) &&
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!test_thread_flag(TIF_RESTORE_TM)) {
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tsk->thread.ckpt_regs.msr = tsk->thread.regs->msr;
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set_thread_flag(TIF_RESTORE_TM);
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}
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giveup_altivec(tsk);
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}
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#else
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#define giveup_fpu_maybe_transactional(tsk) giveup_fpu(tsk)
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#define giveup_altivec_maybe_transactional(tsk) giveup_altivec(tsk)
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#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
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#ifdef CONFIG_PPC_FPU
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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_maybe_transactional(tsk);
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}
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preempt_enable();
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}
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}
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EXPORT_SYMBOL_GPL(flush_fp_to_thread);
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#endif /* CONFIG_PPC_FPU */
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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_maybe_transactional(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_maybe_transactional(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_maybe_transactional(current);
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else
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giveup_altivec_notask();
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#else
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giveup_altivec_maybe_transactional(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_maybe_transactional(tsk);
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}
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preempt_enable();
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}
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}
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EXPORT_SYMBOL_GPL(flush_altivec_to_thread);
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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_maybe_transactional(tsk);
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giveup_altivec_maybe_transactional(tsk);
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__giveup_vsx(tsk);
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}
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EXPORT_SYMBOL(giveup_vsx);
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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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EXPORT_SYMBOL_GPL(flush_vsx_to_thread);
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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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tsk->thread.spefscr = mfspr(SPRN_SPEFSCR);
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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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#ifdef CONFIG_PPC_ADV_DEBUG_REGS
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void do_send_trap(struct pt_regs *regs, unsigned long address,
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unsigned long error_code, int signal_code, int breakpt)
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{
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siginfo_t info;
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current->thread.trap_nr = signal_code;
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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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/* Deliver the signal to userspace */
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info.si_signo = SIGTRAP;
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info.si_errno = breakpt; /* breakpoint or watchpoint id */
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info.si_code = signal_code;
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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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#else /* !CONFIG_PPC_ADV_DEBUG_REGS */
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void do_break (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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current->thread.trap_nr = TRAP_HWBKPT;
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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_break_match(regs))
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return;
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/* Clear the breakpoint */
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hw_breakpoint_disable();
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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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#endif /* CONFIG_PPC_ADV_DEBUG_REGS */
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static DEFINE_PER_CPU(struct arch_hw_breakpoint, current_brk);
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#ifdef CONFIG_PPC_ADV_DEBUG_REGS
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/*
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* Set the debug registers back to their default "safe" values.
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*/
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static void set_debug_reg_defaults(struct thread_struct *thread)
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{
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thread->debug.iac1 = thread->debug.iac2 = 0;
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#if CONFIG_PPC_ADV_DEBUG_IACS > 2
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thread->debug.iac3 = thread->debug.iac4 = 0;
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#endif
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thread->debug.dac1 = thread->debug.dac2 = 0;
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#if CONFIG_PPC_ADV_DEBUG_DVCS > 0
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thread->debug.dvc1 = thread->debug.dvc2 = 0;
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#endif
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thread->debug.dbcr0 = 0;
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#ifdef CONFIG_BOOKE
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/*
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* Force User/Supervisor bits to b11 (user-only MSR[PR]=1)
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*/
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thread->debug.dbcr1 = DBCR1_IAC1US | DBCR1_IAC2US |
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DBCR1_IAC3US | DBCR1_IAC4US;
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/*
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* Force Data Address Compare User/Supervisor bits to be User-only
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* (0b11 MSR[PR]=1) and set all other bits in DBCR2 register to be 0.
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*/
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thread->debug.dbcr2 = DBCR2_DAC1US | DBCR2_DAC2US;
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#else
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thread->debug.dbcr1 = 0;
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#endif
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}
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static void prime_debug_regs(struct debug_reg *debug)
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{
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/*
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* We could have inherited MSR_DE from userspace, since
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* it doesn't get cleared on exception entry. Make sure
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* MSR_DE is clear before we enable any debug events.
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*/
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mtmsr(mfmsr() & ~MSR_DE);
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mtspr(SPRN_IAC1, debug->iac1);
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mtspr(SPRN_IAC2, debug->iac2);
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#if CONFIG_PPC_ADV_DEBUG_IACS > 2
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mtspr(SPRN_IAC3, debug->iac3);
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mtspr(SPRN_IAC4, debug->iac4);
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#endif
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mtspr(SPRN_DAC1, debug->dac1);
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mtspr(SPRN_DAC2, debug->dac2);
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#if CONFIG_PPC_ADV_DEBUG_DVCS > 0
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mtspr(SPRN_DVC1, debug->dvc1);
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mtspr(SPRN_DVC2, debug->dvc2);
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#endif
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mtspr(SPRN_DBCR0, debug->dbcr0);
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mtspr(SPRN_DBCR1, debug->dbcr1);
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#ifdef CONFIG_BOOKE
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mtspr(SPRN_DBCR2, debug->dbcr2);
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#endif
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}
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/*
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* Unless neither the old or new thread are making use of the
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* debug registers, set the debug registers from the values
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* stored in the new thread.
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*/
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void switch_booke_debug_regs(struct debug_reg *new_debug)
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{
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if ((current->thread.debug.dbcr0 & DBCR0_IDM)
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|| (new_debug->dbcr0 & DBCR0_IDM))
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prime_debug_regs(new_debug);
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}
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EXPORT_SYMBOL_GPL(switch_booke_debug_regs);
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#else /* !CONFIG_PPC_ADV_DEBUG_REGS */
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#ifndef CONFIG_HAVE_HW_BREAKPOINT
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static void set_debug_reg_defaults(struct thread_struct *thread)
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{
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thread->hw_brk.address = 0;
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thread->hw_brk.type = 0;
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set_breakpoint(&thread->hw_brk);
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}
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#endif /* !CONFIG_HAVE_HW_BREAKPOINT */
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#endif /* CONFIG_PPC_ADV_DEBUG_REGS */
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#ifdef CONFIG_PPC_ADV_DEBUG_REGS
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static inline int __set_dabr(unsigned long dabr, unsigned long dabrx)
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{
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mtspr(SPRN_DAC1, dabr);
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#ifdef CONFIG_PPC_47x
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isync();
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#endif
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return 0;
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}
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#elif defined(CONFIG_PPC_BOOK3S)
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static inline int __set_dabr(unsigned long dabr, unsigned long dabrx)
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{
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mtspr(SPRN_DABR, dabr);
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if (cpu_has_feature(CPU_FTR_DABRX))
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mtspr(SPRN_DABRX, dabrx);
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return 0;
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}
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#else
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static inline int __set_dabr(unsigned long dabr, unsigned long dabrx)
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{
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return -EINVAL;
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}
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#endif
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static inline int set_dabr(struct arch_hw_breakpoint *brk)
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{
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unsigned long dabr, dabrx;
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dabr = brk->address | (brk->type & HW_BRK_TYPE_DABR);
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dabrx = ((brk->type >> 3) & 0x7);
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if (ppc_md.set_dabr)
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return ppc_md.set_dabr(dabr, dabrx);
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return __set_dabr(dabr, dabrx);
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}
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static inline int set_dawr(struct arch_hw_breakpoint *brk)
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{
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unsigned long dawr, dawrx, mrd;
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dawr = brk->address;
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dawrx = (brk->type & (HW_BRK_TYPE_READ | HW_BRK_TYPE_WRITE)) \
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<< (63 - 58); //* read/write bits */
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dawrx |= ((brk->type & (HW_BRK_TYPE_TRANSLATE)) >> 2) \
|
|
<< (63 - 59); //* translate */
|
|
dawrx |= (brk->type & (HW_BRK_TYPE_PRIV_ALL)) \
|
|
>> 3; //* PRIM bits */
|
|
/* dawr length is stored in field MDR bits 48:53. Matches range in
|
|
doublewords (64 bits) baised by -1 eg. 0b000000=1DW and
|
|
0b111111=64DW.
|
|
brk->len is in bytes.
|
|
This aligns up to double word size, shifts and does the bias.
|
|
*/
|
|
mrd = ((brk->len + 7) >> 3) - 1;
|
|
dawrx |= (mrd & 0x3f) << (63 - 53);
|
|
|
|
if (ppc_md.set_dawr)
|
|
return ppc_md.set_dawr(dawr, dawrx);
|
|
mtspr(SPRN_DAWR, dawr);
|
|
mtspr(SPRN_DAWRX, dawrx);
|
|
return 0;
|
|
}
|
|
|
|
void __set_breakpoint(struct arch_hw_breakpoint *brk)
|
|
{
|
|
memcpy(this_cpu_ptr(¤t_brk), brk, sizeof(*brk));
|
|
|
|
if (cpu_has_feature(CPU_FTR_DAWR))
|
|
set_dawr(brk);
|
|
else
|
|
set_dabr(brk);
|
|
}
|
|
|
|
void set_breakpoint(struct arch_hw_breakpoint *brk)
|
|
{
|
|
preempt_disable();
|
|
__set_breakpoint(brk);
|
|
preempt_enable();
|
|
}
|
|
|
|
#ifdef CONFIG_PPC64
|
|
DEFINE_PER_CPU(struct cpu_usage, cpu_usage_array);
|
|
#endif
|
|
|
|
static inline bool hw_brk_match(struct arch_hw_breakpoint *a,
|
|
struct arch_hw_breakpoint *b)
|
|
{
|
|
if (a->address != b->address)
|
|
return false;
|
|
if (a->type != b->type)
|
|
return false;
|
|
if (a->len != b->len)
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
|
|
static void tm_reclaim_thread(struct thread_struct *thr,
|
|
struct thread_info *ti, uint8_t cause)
|
|
{
|
|
unsigned long msr_diff = 0;
|
|
|
|
/*
|
|
* If FP/VSX registers have been already saved to the
|
|
* thread_struct, move them to the transact_fp array.
|
|
* We clear the TIF_RESTORE_TM bit since after the reclaim
|
|
* the thread will no longer be transactional.
|
|
*/
|
|
if (test_ti_thread_flag(ti, TIF_RESTORE_TM)) {
|
|
msr_diff = thr->ckpt_regs.msr & ~thr->regs->msr;
|
|
if (msr_diff & MSR_FP)
|
|
memcpy(&thr->transact_fp, &thr->fp_state,
|
|
sizeof(struct thread_fp_state));
|
|
if (msr_diff & MSR_VEC)
|
|
memcpy(&thr->transact_vr, &thr->vr_state,
|
|
sizeof(struct thread_vr_state));
|
|
clear_ti_thread_flag(ti, TIF_RESTORE_TM);
|
|
msr_diff &= MSR_FP | MSR_VEC | MSR_VSX | MSR_FE0 | MSR_FE1;
|
|
}
|
|
|
|
tm_reclaim(thr, thr->regs->msr, cause);
|
|
|
|
/* Having done the reclaim, we now have the checkpointed
|
|
* FP/VSX values in the registers. These might be valid
|
|
* even if we have previously called enable_kernel_fp() or
|
|
* flush_fp_to_thread(), so update thr->regs->msr to
|
|
* indicate their current validity.
|
|
*/
|
|
thr->regs->msr |= msr_diff;
|
|
}
|
|
|
|
void tm_reclaim_current(uint8_t cause)
|
|
{
|
|
tm_enable();
|
|
tm_reclaim_thread(¤t->thread, current_thread_info(), cause);
|
|
}
|
|
|
|
static inline void tm_reclaim_task(struct task_struct *tsk)
|
|
{
|
|
/* We have to work out if we're switching from/to a task that's in the
|
|
* middle of a transaction.
|
|
*
|
|
* In switching we need to maintain a 2nd register state as
|
|
* oldtask->thread.ckpt_regs. We tm_reclaim(oldproc); this saves the
|
|
* checkpointed (tbegin) state in ckpt_regs and saves the transactional
|
|
* (current) FPRs into oldtask->thread.transact_fpr[].
|
|
*
|
|
* We also context switch (save) TFHAR/TEXASR/TFIAR in here.
|
|
*/
|
|
struct thread_struct *thr = &tsk->thread;
|
|
|
|
if (!thr->regs)
|
|
return;
|
|
|
|
if (!MSR_TM_ACTIVE(thr->regs->msr))
|
|
goto out_and_saveregs;
|
|
|
|
/* Stash the original thread MSR, as giveup_fpu et al will
|
|
* modify it. We hold onto it to see whether the task used
|
|
* FP & vector regs. If the TIF_RESTORE_TM flag is set,
|
|
* ckpt_regs.msr is already set.
|
|
*/
|
|
if (!test_ti_thread_flag(task_thread_info(tsk), TIF_RESTORE_TM))
|
|
thr->ckpt_regs.msr = thr->regs->msr;
|
|
|
|
TM_DEBUG("--- tm_reclaim on pid %d (NIP=%lx, "
|
|
"ccr=%lx, msr=%lx, trap=%lx)\n",
|
|
tsk->pid, thr->regs->nip,
|
|
thr->regs->ccr, thr->regs->msr,
|
|
thr->regs->trap);
|
|
|
|
tm_reclaim_thread(thr, task_thread_info(tsk), TM_CAUSE_RESCHED);
|
|
|
|
TM_DEBUG("--- tm_reclaim on pid %d complete\n",
|
|
tsk->pid);
|
|
|
|
out_and_saveregs:
|
|
/* Always save the regs here, even if a transaction's not active.
|
|
* This context-switches a thread's TM info SPRs. We do it here to
|
|
* be consistent with the restore path (in recheckpoint) which
|
|
* cannot happen later in _switch().
|
|
*/
|
|
tm_save_sprs(thr);
|
|
}
|
|
|
|
extern void __tm_recheckpoint(struct thread_struct *thread,
|
|
unsigned long orig_msr);
|
|
|
|
void tm_recheckpoint(struct thread_struct *thread,
|
|
unsigned long orig_msr)
|
|
{
|
|
unsigned long flags;
|
|
|
|
/* We really can't be interrupted here as the TEXASR registers can't
|
|
* change and later in the trecheckpoint code, we have a userspace R1.
|
|
* So let's hard disable over this region.
|
|
*/
|
|
local_irq_save(flags);
|
|
hard_irq_disable();
|
|
|
|
/* The TM SPRs are restored here, so that TEXASR.FS can be set
|
|
* before the trecheckpoint and no explosion occurs.
|
|
*/
|
|
tm_restore_sprs(thread);
|
|
|
|
__tm_recheckpoint(thread, orig_msr);
|
|
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
static inline void tm_recheckpoint_new_task(struct task_struct *new)
|
|
{
|
|
unsigned long msr;
|
|
|
|
if (!cpu_has_feature(CPU_FTR_TM))
|
|
return;
|
|
|
|
/* Recheckpoint the registers of the thread we're about to switch to.
|
|
*
|
|
* If the task was using FP, we non-lazily reload both the original and
|
|
* the speculative FP register states. This is because the kernel
|
|
* doesn't see if/when a TM rollback occurs, so if we take an FP
|
|
* unavoidable later, we are unable to determine which set of FP regs
|
|
* need to be restored.
|
|
*/
|
|
if (!new->thread.regs)
|
|
return;
|
|
|
|
if (!MSR_TM_ACTIVE(new->thread.regs->msr)){
|
|
tm_restore_sprs(&new->thread);
|
|
return;
|
|
}
|
|
msr = new->thread.ckpt_regs.msr;
|
|
/* Recheckpoint to restore original checkpointed register state. */
|
|
TM_DEBUG("*** tm_recheckpoint of pid %d "
|
|
"(new->msr 0x%lx, new->origmsr 0x%lx)\n",
|
|
new->pid, new->thread.regs->msr, msr);
|
|
|
|
/* This loads the checkpointed FP/VEC state, if used */
|
|
tm_recheckpoint(&new->thread, msr);
|
|
|
|
/* This loads the speculative FP/VEC state, if used */
|
|
if (msr & MSR_FP) {
|
|
do_load_up_transact_fpu(&new->thread);
|
|
new->thread.regs->msr |=
|
|
(MSR_FP | new->thread.fpexc_mode);
|
|
}
|
|
#ifdef CONFIG_ALTIVEC
|
|
if (msr & MSR_VEC) {
|
|
do_load_up_transact_altivec(&new->thread);
|
|
new->thread.regs->msr |= MSR_VEC;
|
|
}
|
|
#endif
|
|
/* We may as well turn on VSX too since all the state is restored now */
|
|
if (msr & MSR_VSX)
|
|
new->thread.regs->msr |= MSR_VSX;
|
|
|
|
TM_DEBUG("*** tm_recheckpoint of pid %d complete "
|
|
"(kernel msr 0x%lx)\n",
|
|
new->pid, mfmsr());
|
|
}
|
|
|
|
static inline void __switch_to_tm(struct task_struct *prev)
|
|
{
|
|
if (cpu_has_feature(CPU_FTR_TM)) {
|
|
tm_enable();
|
|
tm_reclaim_task(prev);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* This is called if we are on the way out to userspace and the
|
|
* TIF_RESTORE_TM flag is set. It checks if we need to reload
|
|
* FP and/or vector state and does so if necessary.
|
|
* If userspace is inside a transaction (whether active or
|
|
* suspended) and FP/VMX/VSX instructions have ever been enabled
|
|
* inside that transaction, then we have to keep them enabled
|
|
* and keep the FP/VMX/VSX state loaded while ever the transaction
|
|
* continues. The reason is that if we didn't, and subsequently
|
|
* got a FP/VMX/VSX unavailable interrupt inside a transaction,
|
|
* we don't know whether it's the same transaction, and thus we
|
|
* don't know which of the checkpointed state and the transactional
|
|
* state to use.
|
|
*/
|
|
void restore_tm_state(struct pt_regs *regs)
|
|
{
|
|
unsigned long msr_diff;
|
|
|
|
clear_thread_flag(TIF_RESTORE_TM);
|
|
if (!MSR_TM_ACTIVE(regs->msr))
|
|
return;
|
|
|
|
msr_diff = current->thread.ckpt_regs.msr & ~regs->msr;
|
|
msr_diff &= MSR_FP | MSR_VEC | MSR_VSX;
|
|
if (msr_diff & MSR_FP) {
|
|
fp_enable();
|
|
load_fp_state(¤t->thread.fp_state);
|
|
regs->msr |= current->thread.fpexc_mode;
|
|
}
|
|
if (msr_diff & MSR_VEC) {
|
|
vec_enable();
|
|
load_vr_state(¤t->thread.vr_state);
|
|
}
|
|
regs->msr |= msr_diff;
|
|
}
|
|
|
|
#else
|
|
#define tm_recheckpoint_new_task(new)
|
|
#define __switch_to_tm(prev)
|
|
#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
|
|
|
|
struct task_struct *__switch_to(struct task_struct *prev,
|
|
struct task_struct *new)
|
|
{
|
|
struct thread_struct *new_thread, *old_thread;
|
|
struct task_struct *last;
|
|
#ifdef CONFIG_PPC_BOOK3S_64
|
|
struct ppc64_tlb_batch *batch;
|
|
#endif
|
|
|
|
WARN_ON(!irqs_disabled());
|
|
|
|
/* Back up the TAR and DSCR across context switches.
|
|
* Note that the TAR is not available for use in the kernel. (To
|
|
* provide this, the TAR should be backed up/restored on exception
|
|
* entry/exit instead, and be in pt_regs. FIXME, this should be in
|
|
* pt_regs anyway (for debug).)
|
|
* Save the TAR and DSCR here before we do treclaim/trecheckpoint as
|
|
* these will change them.
|
|
*/
|
|
save_early_sprs(&prev->thread);
|
|
|
|
__switch_to_tm(prev);
|
|
|
|
#ifdef CONFIG_SMP
|
|
/* avoid complexity of lazy save/restore of fpu
|
|
* by just saving it every time we switch out if
|
|
* this task used the fpu during the last quantum.
|
|
*
|
|
* If it tries to use the fpu again, it'll trap and
|
|
* reload its fp regs. So we don't have to do a restore
|
|
* every switch, just a save.
|
|
* -- Cort
|
|
*/
|
|
if (prev->thread.regs && (prev->thread.regs->msr & MSR_FP))
|
|
giveup_fpu(prev);
|
|
#ifdef CONFIG_ALTIVEC
|
|
/*
|
|
* If the previous thread used altivec in the last quantum
|
|
* (thus changing altivec regs) then save them.
|
|
* We used to check the VRSAVE register but not all apps
|
|
* set it, so we don't rely on it now (and in fact we need
|
|
* to save & restore VSCR even if VRSAVE == 0). -- paulus
|
|
*
|
|
* On SMP we always save/restore altivec regs just to avoid the
|
|
* complexity of changing processors.
|
|
* -- Cort
|
|
*/
|
|
if (prev->thread.regs && (prev->thread.regs->msr & MSR_VEC))
|
|
giveup_altivec(prev);
|
|
#endif /* CONFIG_ALTIVEC */
|
|
#ifdef CONFIG_VSX
|
|
if (prev->thread.regs && (prev->thread.regs->msr & MSR_VSX))
|
|
/* VMX and FPU registers are already save here */
|
|
__giveup_vsx(prev);
|
|
#endif /* CONFIG_VSX */
|
|
#ifdef CONFIG_SPE
|
|
/*
|
|
* If the previous thread used spe in the last quantum
|
|
* (thus changing spe regs) then save them.
|
|
*
|
|
* On SMP we always save/restore spe regs just to avoid the
|
|
* complexity of changing processors.
|
|
*/
|
|
if ((prev->thread.regs && (prev->thread.regs->msr & MSR_SPE)))
|
|
giveup_spe(prev);
|
|
#endif /* CONFIG_SPE */
|
|
|
|
#else /* CONFIG_SMP */
|
|
#ifdef CONFIG_ALTIVEC
|
|
/* Avoid the trap. On smp this this never happens since
|
|
* we don't set last_task_used_altivec -- Cort
|
|
*/
|
|
if (new->thread.regs && last_task_used_altivec == new)
|
|
new->thread.regs->msr |= MSR_VEC;
|
|
#endif /* CONFIG_ALTIVEC */
|
|
#ifdef CONFIG_VSX
|
|
if (new->thread.regs && last_task_used_vsx == new)
|
|
new->thread.regs->msr |= MSR_VSX;
|
|
#endif /* CONFIG_VSX */
|
|
#ifdef CONFIG_SPE
|
|
/* Avoid the trap. On smp this this never happens since
|
|
* we don't set last_task_used_spe
|
|
*/
|
|
if (new->thread.regs && last_task_used_spe == new)
|
|
new->thread.regs->msr |= MSR_SPE;
|
|
#endif /* CONFIG_SPE */
|
|
|
|
#endif /* CONFIG_SMP */
|
|
|
|
#ifdef CONFIG_PPC_ADV_DEBUG_REGS
|
|
switch_booke_debug_regs(&new->thread.debug);
|
|
#else
|
|
/*
|
|
* For PPC_BOOK3S_64, we use the hw-breakpoint interfaces that would
|
|
* schedule DABR
|
|
*/
|
|
#ifndef CONFIG_HAVE_HW_BREAKPOINT
|
|
if (unlikely(!hw_brk_match(this_cpu_ptr(¤t_brk), &new->thread.hw_brk)))
|
|
__set_breakpoint(&new->thread.hw_brk);
|
|
#endif /* CONFIG_HAVE_HW_BREAKPOINT */
|
|
#endif
|
|
|
|
|
|
new_thread = &new->thread;
|
|
old_thread = ¤t->thread;
|
|
|
|
#ifdef CONFIG_PPC64
|
|
/*
|
|
* Collect processor utilization data per process
|
|
*/
|
|
if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
|
|
struct cpu_usage *cu = this_cpu_ptr(&cpu_usage_array);
|
|
long unsigned start_tb, current_tb;
|
|
start_tb = old_thread->start_tb;
|
|
cu->current_tb = current_tb = mfspr(SPRN_PURR);
|
|
old_thread->accum_tb += (current_tb - start_tb);
|
|
new_thread->start_tb = current_tb;
|
|
}
|
|
#endif /* CONFIG_PPC64 */
|
|
|
|
#ifdef CONFIG_PPC_BOOK3S_64
|
|
batch = this_cpu_ptr(&ppc64_tlb_batch);
|
|
if (batch->active) {
|
|
current_thread_info()->local_flags |= _TLF_LAZY_MMU;
|
|
if (batch->index)
|
|
__flush_tlb_pending(batch);
|
|
batch->active = 0;
|
|
}
|
|
#endif /* CONFIG_PPC_BOOK3S_64 */
|
|
|
|
/*
|
|
* We can't take a PMU exception inside _switch() since there is a
|
|
* window where the kernel stack SLB and the kernel stack are out
|
|
* of sync. Hard disable here.
|
|
*/
|
|
hard_irq_disable();
|
|
|
|
tm_recheckpoint_new_task(new);
|
|
|
|
last = _switch(old_thread, new_thread);
|
|
|
|
#ifdef CONFIG_PPC_BOOK3S_64
|
|
if (current_thread_info()->local_flags & _TLF_LAZY_MMU) {
|
|
current_thread_info()->local_flags &= ~_TLF_LAZY_MMU;
|
|
batch = this_cpu_ptr(&ppc64_tlb_batch);
|
|
batch->active = 1;
|
|
}
|
|
#endif /* CONFIG_PPC_BOOK3S_64 */
|
|
|
|
return last;
|
|
}
|
|
|
|
static int instructions_to_print = 16;
|
|
|
|
static void show_instructions(struct pt_regs *regs)
|
|
{
|
|
int i;
|
|
unsigned long pc = regs->nip - (instructions_to_print * 3 / 4 *
|
|
sizeof(int));
|
|
|
|
printk("Instruction dump:");
|
|
|
|
for (i = 0; i < instructions_to_print; i++) {
|
|
int instr;
|
|
|
|
if (!(i % 8))
|
|
printk("\n");
|
|
|
|
#if !defined(CONFIG_BOOKE)
|
|
/* If executing with the IMMU off, adjust pc rather
|
|
* than print XXXXXXXX.
|
|
*/
|
|
if (!(regs->msr & MSR_IR))
|
|
pc = (unsigned long)phys_to_virt(pc);
|
|
#endif
|
|
|
|
if (!__kernel_text_address(pc) ||
|
|
probe_kernel_address((unsigned int __user *)pc, instr)) {
|
|
printk(KERN_CONT "XXXXXXXX ");
|
|
} else {
|
|
if (regs->nip == pc)
|
|
printk(KERN_CONT "<%08x> ", instr);
|
|
else
|
|
printk(KERN_CONT "%08x ", instr);
|
|
}
|
|
|
|
pc += sizeof(int);
|
|
}
|
|
|
|
printk("\n");
|
|
}
|
|
|
|
static struct regbit {
|
|
unsigned long bit;
|
|
const char *name;
|
|
} msr_bits[] = {
|
|
#if defined(CONFIG_PPC64) && !defined(CONFIG_BOOKE)
|
|
{MSR_SF, "SF"},
|
|
{MSR_HV, "HV"},
|
|
#endif
|
|
{MSR_VEC, "VEC"},
|
|
{MSR_VSX, "VSX"},
|
|
#ifdef CONFIG_BOOKE
|
|
{MSR_CE, "CE"},
|
|
#endif
|
|
{MSR_EE, "EE"},
|
|
{MSR_PR, "PR"},
|
|
{MSR_FP, "FP"},
|
|
{MSR_ME, "ME"},
|
|
#ifdef CONFIG_BOOKE
|
|
{MSR_DE, "DE"},
|
|
#else
|
|
{MSR_SE, "SE"},
|
|
{MSR_BE, "BE"},
|
|
#endif
|
|
{MSR_IR, "IR"},
|
|
{MSR_DR, "DR"},
|
|
{MSR_PMM, "PMM"},
|
|
#ifndef CONFIG_BOOKE
|
|
{MSR_RI, "RI"},
|
|
{MSR_LE, "LE"},
|
|
#endif
|
|
{0, NULL}
|
|
};
|
|
|
|
static void printbits(unsigned long val, struct regbit *bits)
|
|
{
|
|
const char *sep = "";
|
|
|
|
printk("<");
|
|
for (; bits->bit; ++bits)
|
|
if (val & bits->bit) {
|
|
printk("%s%s", sep, bits->name);
|
|
sep = ",";
|
|
}
|
|
printk(">");
|
|
}
|
|
|
|
#ifdef CONFIG_PPC64
|
|
#define REG "%016lx"
|
|
#define REGS_PER_LINE 4
|
|
#define LAST_VOLATILE 13
|
|
#else
|
|
#define REG "%08lx"
|
|
#define REGS_PER_LINE 8
|
|
#define LAST_VOLATILE 12
|
|
#endif
|
|
|
|
void show_regs(struct pt_regs * regs)
|
|
{
|
|
int i, trap;
|
|
|
|
show_regs_print_info(KERN_DEFAULT);
|
|
|
|
printk("NIP: "REG" LR: "REG" CTR: "REG"\n",
|
|
regs->nip, regs->link, regs->ctr);
|
|
printk("REGS: %p TRAP: %04lx %s (%s)\n",
|
|
regs, regs->trap, print_tainted(), init_utsname()->release);
|
|
printk("MSR: "REG" ", regs->msr);
|
|
printbits(regs->msr, msr_bits);
|
|
printk(" CR: %08lx XER: %08lx\n", regs->ccr, regs->xer);
|
|
trap = TRAP(regs);
|
|
if ((regs->trap != 0xc00) && cpu_has_feature(CPU_FTR_CFAR))
|
|
printk("CFAR: "REG" ", regs->orig_gpr3);
|
|
if (trap == 0x200 || trap == 0x300 || trap == 0x600)
|
|
#if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
|
|
printk("DEAR: "REG" ESR: "REG" ", regs->dar, regs->dsisr);
|
|
#else
|
|
printk("DAR: "REG" DSISR: %08lx ", regs->dar, regs->dsisr);
|
|
#endif
|
|
#ifdef CONFIG_PPC64
|
|
printk("SOFTE: %ld ", regs->softe);
|
|
#endif
|
|
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
|
|
if (MSR_TM_ACTIVE(regs->msr))
|
|
printk("\nPACATMSCRATCH: %016llx ", get_paca()->tm_scratch);
|
|
#endif
|
|
|
|
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)
|
|
{
|
|
discard_lazy_cpu_state();
|
|
|
|
#ifdef CONFIG_HAVE_HW_BREAKPOINT
|
|
flush_ptrace_hw_breakpoint(current);
|
|
#else /* CONFIG_HAVE_HW_BREAKPOINT */
|
|
set_debug_reg_defaults(¤t->thread);
|
|
#endif /* CONFIG_HAVE_HW_BREAKPOINT */
|
|
}
|
|
|
|
void
|
|
release_thread(struct task_struct *t)
|
|
{
|
|
}
|
|
|
|
/*
|
|
* this gets called so that we can store coprocessor state into memory and
|
|
* copy the current task into the new thread.
|
|
*/
|
|
int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
|
|
{
|
|
flush_fp_to_thread(src);
|
|
flush_altivec_to_thread(src);
|
|
flush_vsx_to_thread(src);
|
|
flush_spe_to_thread(src);
|
|
/*
|
|
* Flush TM state out so we can copy it. __switch_to_tm() does this
|
|
* flush but it removes the checkpointed state from the current CPU and
|
|
* transitions the CPU out of TM mode. Hence we need to call
|
|
* tm_recheckpoint_new_task() (on the same task) to restore the
|
|
* checkpointed state back and the TM mode.
|
|
*/
|
|
__switch_to_tm(src);
|
|
tm_recheckpoint_new_task(src);
|
|
|
|
*dst = *src;
|
|
|
|
clear_task_ebb(dst);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void setup_ksp_vsid(struct task_struct *p, unsigned long sp)
|
|
{
|
|
#ifdef CONFIG_PPC_STD_MMU_64
|
|
unsigned long sp_vsid;
|
|
unsigned long llp = mmu_psize_defs[mmu_linear_psize].sllp;
|
|
|
|
if (mmu_has_feature(MMU_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
|
|
}
|
|
|
|
/*
|
|
* Copy a thread..
|
|
*/
|
|
|
|
/*
|
|
* Copy architecture-specific thread state
|
|
*/
|
|
int copy_thread(unsigned long clone_flags, unsigned long usp,
|
|
unsigned long kthread_arg, struct task_struct *p)
|
|
{
|
|
struct pt_regs *childregs, *kregs;
|
|
extern void ret_from_fork(void);
|
|
extern void ret_from_kernel_thread(void);
|
|
void (*f)(void);
|
|
unsigned long sp = (unsigned long)task_stack_page(p) + THREAD_SIZE;
|
|
|
|
/* Copy registers */
|
|
sp -= sizeof(struct pt_regs);
|
|
childregs = (struct pt_regs *) sp;
|
|
if (unlikely(p->flags & PF_KTHREAD)) {
|
|
/* kernel thread */
|
|
struct thread_info *ti = (void *)task_stack_page(p);
|
|
memset(childregs, 0, sizeof(struct pt_regs));
|
|
childregs->gpr[1] = sp + sizeof(struct pt_regs);
|
|
/* function */
|
|
if (usp)
|
|
childregs->gpr[14] = ppc_function_entry((void *)usp);
|
|
#ifdef CONFIG_PPC64
|
|
clear_tsk_thread_flag(p, TIF_32BIT);
|
|
childregs->softe = 1;
|
|
#endif
|
|
childregs->gpr[15] = kthread_arg;
|
|
p->thread.regs = NULL; /* no user register state */
|
|
ti->flags |= _TIF_RESTOREALL;
|
|
f = ret_from_kernel_thread;
|
|
} else {
|
|
/* user thread */
|
|
struct pt_regs *regs = current_pt_regs();
|
|
CHECK_FULL_REGS(regs);
|
|
*childregs = *regs;
|
|
if (usp)
|
|
childregs->gpr[1] = usp;
|
|
p->thread.regs = childregs;
|
|
childregs->gpr[3] = 0; /* Result from fork() */
|
|
if (clone_flags & CLONE_SETTLS) {
|
|
#ifdef CONFIG_PPC64
|
|
if (!is_32bit_task())
|
|
childregs->gpr[13] = childregs->gpr[6];
|
|
else
|
|
#endif
|
|
childregs->gpr[2] = childregs->gpr[6];
|
|
}
|
|
|
|
f = ret_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.
|
|
*/
|
|
((unsigned long *)sp)[0] = 0;
|
|
sp -= sizeof(struct pt_regs);
|
|
kregs = (struct pt_regs *) sp;
|
|
sp -= STACK_FRAME_OVERHEAD;
|
|
p->thread.ksp = sp;
|
|
#ifdef CONFIG_PPC32
|
|
p->thread.ksp_limit = (unsigned long)task_stack_page(p) +
|
|
_ALIGN_UP(sizeof(struct thread_info), 16);
|
|
#endif
|
|
#ifdef CONFIG_HAVE_HW_BREAKPOINT
|
|
p->thread.ptrace_bps[0] = NULL;
|
|
#endif
|
|
|
|
p->thread.fp_save_area = NULL;
|
|
#ifdef CONFIG_ALTIVEC
|
|
p->thread.vr_save_area = NULL;
|
|
#endif
|
|
|
|
setup_ksp_vsid(p, sp);
|
|
|
|
#ifdef CONFIG_PPC64
|
|
if (cpu_has_feature(CPU_FTR_DSCR)) {
|
|
p->thread.dscr_inherit = current->thread.dscr_inherit;
|
|
p->thread.dscr = current->thread.dscr;
|
|
}
|
|
if (cpu_has_feature(CPU_FTR_HAS_PPR))
|
|
p->thread.ppr = INIT_PPR;
|
|
#endif
|
|
kregs->nip = ppc_function_entry(f);
|
|
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
|
|
|
|
/*
|
|
* 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 (!is_32bit_task()) {
|
|
unsigned long entry;
|
|
|
|
if (is_elf2_task()) {
|
|
/* Look ma, no function descriptors! */
|
|
entry = start;
|
|
|
|
/*
|
|
* Ulrich says:
|
|
* The latest iteration of the ABI requires that when
|
|
* calling a function (at its global entry point),
|
|
* the caller must ensure r12 holds the entry point
|
|
* address (so that the function can quickly
|
|
* establish addressability).
|
|
*/
|
|
regs->gpr[12] = start;
|
|
/* Make sure that's restored on entry to userspace. */
|
|
set_thread_flag(TIF_RESTOREALL);
|
|
} else {
|
|
unsigned long 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->gpr[2] = toc;
|
|
}
|
|
regs->nip = entry;
|
|
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(¤t->thread.fp_state, 0, sizeof(current->thread.fp_state));
|
|
current->thread.fp_save_area = NULL;
|
|
#ifdef CONFIG_ALTIVEC
|
|
memset(¤t->thread.vr_state, 0, sizeof(current->thread.vr_state));
|
|
current->thread.vr_state.vscr.u[3] = 0x00010000; /* Java mode disabled */
|
|
current->thread.vr_save_area = NULL;
|
|
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 */
|
|
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
|
|
if (cpu_has_feature(CPU_FTR_TM))
|
|
regs->msr |= MSR_TM;
|
|
current->thread.tm_tfhar = 0;
|
|
current->thread.tm_texasr = 0;
|
|
current->thread.tm_tfiar = 0;
|
|
#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
|
|
}
|
|
EXPORT_SYMBOL(start_thread);
|
|
|
|
#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)) {
|
|
/*
|
|
* When the sticky exception bits are set
|
|
* directly by userspace, it must call prctl
|
|
* with PR_GET_FPEXC (with PR_FP_EXC_SW_ENABLE
|
|
* in the existing prctl settings) or
|
|
* PR_SET_FPEXC (with PR_FP_EXC_SW_ENABLE in
|
|
* the bits being set). <fenv.h> functions
|
|
* saving and restoring the whole
|
|
* floating-point environment need to do so
|
|
* anyway to restore the prctl settings from
|
|
* the saved environment.
|
|
*/
|
|
tsk->thread.spefscr_last = mfspr(SPRN_SPEFSCR);
|
|
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)) {
|
|
/*
|
|
* When the sticky exception bits are set
|
|
* directly by userspace, it must call prctl
|
|
* with PR_GET_FPEXC (with PR_FP_EXC_SW_ENABLE
|
|
* in the existing prctl settings) or
|
|
* PR_SET_FPEXC (with PR_FP_EXC_SW_ENABLE in
|
|
* the bits being set). <fenv.h> functions
|
|
* saving and restoring the whole
|
|
* floating-point environment need to do so
|
|
* anyway to restore the prctl settings from
|
|
* the saved environment.
|
|
*/
|
|
tsk->thread.spefscr_last = mfspr(SPRN_SPEFSCR);
|
|
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);
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
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 rth = (unsigned long)return_to_handler;
|
|
#endif
|
|
|
|
sp = (unsigned long) stack;
|
|
if (tsk == NULL)
|
|
tsk = current;
|
|
if (sp == 0) {
|
|
if (tsk == current)
|
|
sp = current_stack_pointer();
|
|
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 == rth) && 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("--- interrupt: %lx at %pS\n LR = %pS\n",
|
|
regs->trap, (void *)regs->nip, (void *)lr);
|
|
firstframe = 1;
|
|
}
|
|
|
|
sp = newsp;
|
|
} while (count++ < kstack_depth_to_print);
|
|
}
|
|
|
|
#ifdef CONFIG_PPC64
|
|
/* Called with hard IRQs off */
|
|
void notrace __ppc64_runlatch_on(void)
|
|
{
|
|
struct thread_info *ti = current_thread_info();
|
|
unsigned long ctrl;
|
|
|
|
ctrl = mfspr(SPRN_CTRLF);
|
|
ctrl |= CTRL_RUNLATCH;
|
|
mtspr(SPRN_CTRLT, ctrl);
|
|
|
|
ti->local_flags |= _TLF_RUNLATCH;
|
|
}
|
|
|
|
/* Called with hard IRQs off */
|
|
void notrace __ppc64_runlatch_off(void)
|
|
{
|
|
struct thread_info *ti = current_thread_info();
|
|
unsigned long ctrl;
|
|
|
|
ti->local_flags &= ~_TLF_RUNLATCH;
|
|
|
|
ctrl = mfspr(SPRN_CTRLF);
|
|
ctrl &= ~CTRL_RUNLATCH;
|
|
mtspr(SPRN_CTRLT, ctrl);
|
|
}
|
|
#endif /* CONFIG_PPC64 */
|
|
|
|
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 base = mm->brk;
|
|
unsigned long ret;
|
|
|
|
#ifdef CONFIG_PPC_STD_MMU_64
|
|
/*
|
|
* If we are using 1TB segments and we are allowed to randomise
|
|
* the heap, we can put it above 1TB so it is backed by a 1TB
|
|
* segment. Otherwise the heap will be in the bottom 1TB
|
|
* which always uses 256MB segments and this may result in a
|
|
* performance penalty.
|
|
*/
|
|
if (!is_32bit_task() && (mmu_highuser_ssize == MMU_SEGSIZE_1T))
|
|
base = max_t(unsigned long, mm->brk, 1UL << SID_SHIFT_1T);
|
|
#endif
|
|
|
|
ret = PAGE_ALIGN(base + brk_rnd());
|
|
|
|
if (ret < mm->brk)
|
|
return mm->brk;
|
|
|
|
return ret;
|
|
}
|
|
|