diff options
Diffstat (limited to 'arch/ppc/kernel/process.c')
| -rw-r--r-- | arch/ppc/kernel/process.c | 142 |
1 files changed, 103 insertions, 39 deletions
diff --git a/arch/ppc/kernel/process.c b/arch/ppc/kernel/process.c index 82de66e4db6..cb1c7b92f8c 100644 --- a/arch/ppc/kernel/process.c +++ b/arch/ppc/kernel/process.c @@ -152,18 +152,66 @@ int check_stack(struct task_struct *tsk) } #endif /* defined(CHECK_STACK) */ -#ifdef CONFIG_ALTIVEC -int -dump_altivec(struct pt_regs *regs, elf_vrregset_t *vrregs) +/* + * Make sure the floating-point register state in the + * the thread_struct is up to date for task tsk. + */ +void flush_fp_to_thread(struct task_struct *tsk) { - if (regs->msr & MSR_VEC) - giveup_altivec(current); - memcpy(vrregs, ¤t->thread.vr[0], sizeof(*vrregs)); + if (tsk->thread.regs) { + /* + * We need to disable preemption here because if we didn't, + * another process could get scheduled after the regs->msr + * test but before we have finished saving the FP registers + * to the thread_struct. That process could take over the + * FPU, and then when we get scheduled again we would store + * bogus values for the remaining FP registers. + */ + preempt_disable(); + if (tsk->thread.regs->msr & MSR_FP) { +#ifdef CONFIG_SMP + /* + * This should only ever be called for current or + * for a stopped child process. Since we save away + * the FP register state on context switch on SMP, + * there is something wrong if a stopped child appears + * to still have its FP state in the CPU registers. + */ + BUG_ON(tsk != current); +#endif + giveup_fpu(current); + } + preempt_enable(); + } +} + +void enable_kernel_fp(void) +{ + WARN_ON(preemptible()); + +#ifdef CONFIG_SMP + if (current->thread.regs && (current->thread.regs->msr & MSR_FP)) + giveup_fpu(current); + else + giveup_fpu(NULL); /* just enables FP for kernel */ +#else + giveup_fpu(last_task_used_math); +#endif /* CONFIG_SMP */ +} +EXPORT_SYMBOL(enable_kernel_fp); + +int dump_task_fpu(struct task_struct *tsk, elf_fpregset_t *fpregs) +{ + preempt_disable(); + if (tsk->thread.regs && (tsk->thread.regs->msr & MSR_FP)) + giveup_fpu(tsk); + preempt_enable(); + memcpy(fpregs, &tsk->thread.fpr[0], sizeof(*fpregs)); return 1; } -void -enable_kernel_altivec(void) +#ifdef CONFIG_ALTIVEC +void enable_kernel_altivec(void) { WARN_ON(preemptible()); @@ -177,19 +225,35 @@ enable_kernel_altivec(void) #endif /* __SMP __ */ } EXPORT_SYMBOL(enable_kernel_altivec); -#endif /* CONFIG_ALTIVEC */ -#ifdef CONFIG_SPE -int -dump_spe(struct pt_regs *regs, elf_vrregset_t *evrregs) +/* + * Make sure the VMX/Altivec register state in the + * the thread_struct is up to date for task tsk. + */ +void flush_altivec_to_thread(struct task_struct *tsk) { - if (regs->msr & MSR_SPE) - giveup_spe(current); - /* We copy u32 evr[32] + u64 acc + u32 spefscr -> 35 */ - memcpy(evrregs, ¤t->thread.evr[0], sizeof(u32) * 35); + if (tsk->thread.regs) { + preempt_disable(); + if (tsk->thread.regs->msr & MSR_VEC) { +#ifdef CONFIG_SMP + BUG_ON(tsk != current); +#endif + giveup_altivec(current); + } + preempt_enable(); + } +} + +int dump_altivec(struct pt_regs *regs, elf_vrregset_t *vrregs) +{ + if (regs->msr & MSR_VEC) + giveup_altivec(current); + memcpy(vrregs, ¤t->thread.vr[0], sizeof(*vrregs)); return 1; } +#endif /* CONFIG_ALTIVEC */ +#ifdef CONFIG_SPE void enable_kernel_spe(void) { @@ -205,34 +269,30 @@ enable_kernel_spe(void) #endif /* __SMP __ */ } EXPORT_SYMBOL(enable_kernel_spe); -#endif /* CONFIG_SPE */ -void -enable_kernel_fp(void) +void flush_spe_to_thread(struct task_struct *tsk) { - WARN_ON(preemptible()); - + if (tsk->thread.regs) { + preempt_disable(); + if (tsk->thread.regs->msr & MSR_SPE) { #ifdef CONFIG_SMP - if (current->thread.regs && (current->thread.regs->msr & MSR_FP)) - giveup_fpu(current); - else - giveup_fpu(NULL); /* just enables FP for kernel */ -#else - giveup_fpu(last_task_used_math); -#endif /* CONFIG_SMP */ + BUG_ON(tsk != current); +#endif + giveup_spe(current); + } + preempt_enable(); + } } -EXPORT_SYMBOL(enable_kernel_fp); -int -dump_task_fpu(struct task_struct *tsk, elf_fpregset_t *fpregs) +int dump_spe(struct pt_regs *regs, elf_vrregset_t *evrregs) { - preempt_disable(); - if (tsk->thread.regs && (tsk->thread.regs->msr & MSR_FP)) - giveup_fpu(tsk); - preempt_enable(); - memcpy(fpregs, &tsk->thread.fpr[0], sizeof(*fpregs)); + if (regs->msr & MSR_SPE) + giveup_spe(current); + /* We copy u32 evr[32] + u64 acc + u32 spefscr -> 35 */ + memcpy(evrregs, ¤t->thread.evr[0], sizeof(u32) * 35); return 1; } +#endif /* CONFIG_SPE */ struct task_struct *__switch_to(struct task_struct *prev, struct task_struct *new) @@ -287,11 +347,13 @@ struct task_struct *__switch_to(struct task_struct *prev, #endif /* CONFIG_SPE */ #endif /* 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 #ifdef CONFIG_SPE /* Avoid the trap. On smp this this never happens since * we don't set last_task_used_spe @@ -482,7 +544,7 @@ void start_thread(struct pt_regs *regs, unsigned long nip, unsigned long sp) last_task_used_spe = NULL; #endif memset(current->thread.fpr, 0, sizeof(current->thread.fpr)); - current->thread.fpscr = 0; + 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)); @@ -557,14 +619,16 @@ int sys_clone(unsigned long clone_flags, unsigned long usp, return do_fork(clone_flags, usp, regs, 0, parent_tidp, child_tidp); } -int sys_fork(int p1, int p2, int p3, int p4, int p5, int p6, +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(int p1, int p2, int p3, int p4, int p5, int p6, +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); |