2 * Derived from "arch/i386/kernel/process.c"
3 * Copyright (C) 1995 Linus Torvalds
5 * Updated and modified by Cort Dougan (cort@cs.nmt.edu) and
6 * Paul Mackerras (paulus@cs.anu.edu.au)
9 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version
14 * 2 of the License, or (at your option) any later version.
17 #include <linux/errno.h>
18 #include <linux/sched.h>
19 #include <linux/kernel.h>
21 #include <linux/smp.h>
22 #include <linux/stddef.h>
23 #include <linux/unistd.h>
24 #include <linux/ptrace.h>
25 #include <linux/slab.h>
26 #include <linux/user.h>
27 #include <linux/elf.h>
28 #include <linux/prctl.h>
29 #include <linux/init_task.h>
30 #include <linux/export.h>
31 #include <linux/kallsyms.h>
32 #include <linux/mqueue.h>
33 #include <linux/hardirq.h>
34 #include <linux/utsname.h>
35 #include <linux/ftrace.h>
36 #include <linux/kernel_stat.h>
37 #include <linux/personality.h>
38 #include <linux/random.h>
39 #include <linux/hw_breakpoint.h>
40 #include <linux/uaccess.h>
41 #include <linux/elf-randomize.h>
43 #include <asm/pgtable.h>
45 #include <asm/processor.h>
48 #include <asm/machdep.h>
50 #include <asm/runlatch.h>
51 #include <asm/syscalls.h>
52 #include <asm/switch_to.h>
54 #include <asm/debug.h>
56 #include <asm/firmware.h>
58 #include <asm/code-patching.h>
60 #include <asm/livepatch.h>
62 #include <linux/kprobes.h>
63 #include <linux/kdebug.h>
65 /* Transactional Memory debug */
67 #define TM_DEBUG(x...) printk(KERN_INFO x)
69 #define TM_DEBUG(x...) do { } while(0)
72 extern unsigned long _get_SP(void);
74 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
75 static void check_if_tm_restore_required(struct task_struct *tsk)
78 * If we are saving the current thread's registers, and the
79 * thread is in a transactional state, set the TIF_RESTORE_TM
80 * bit so that we know to restore the registers before
81 * returning to userspace.
83 if (tsk == current && tsk->thread.regs &&
84 MSR_TM_ACTIVE(tsk->thread.regs->msr) &&
85 !test_thread_flag(TIF_RESTORE_TM)) {
86 tsk->thread.ckpt_regs.msr = tsk->thread.regs->msr;
87 set_thread_flag(TIF_RESTORE_TM);
91 static inline void check_if_tm_restore_required(struct task_struct *tsk) { }
92 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
94 bool strict_msr_control;
95 EXPORT_SYMBOL(strict_msr_control);
97 static int __init enable_strict_msr_control(char *str)
99 strict_msr_control = true;
100 pr_info("Enabling strict facility control\n");
104 early_param("ppc_strict_facility_enable", enable_strict_msr_control);
106 void msr_check_and_set(unsigned long bits)
108 unsigned long oldmsr = mfmsr();
109 unsigned long newmsr;
111 newmsr = oldmsr | bits;
114 if (cpu_has_feature(CPU_FTR_VSX) && (bits & MSR_FP))
118 if (oldmsr != newmsr)
122 void __msr_check_and_clear(unsigned long bits)
124 unsigned long oldmsr = mfmsr();
125 unsigned long newmsr;
127 newmsr = oldmsr & ~bits;
130 if (cpu_has_feature(CPU_FTR_VSX) && (bits & MSR_FP))
134 if (oldmsr != newmsr)
137 EXPORT_SYMBOL(__msr_check_and_clear);
139 #ifdef CONFIG_PPC_FPU
140 void __giveup_fpu(struct task_struct *tsk)
143 tsk->thread.regs->msr &= ~MSR_FP;
145 if (cpu_has_feature(CPU_FTR_VSX))
146 tsk->thread.regs->msr &= ~MSR_VSX;
150 void giveup_fpu(struct task_struct *tsk)
152 check_if_tm_restore_required(tsk);
154 msr_check_and_set(MSR_FP);
156 msr_check_and_clear(MSR_FP);
158 EXPORT_SYMBOL(giveup_fpu);
161 * Make sure the floating-point register state in the
162 * the thread_struct is up to date for task tsk.
164 void flush_fp_to_thread(struct task_struct *tsk)
166 if (tsk->thread.regs) {
168 * We need to disable preemption here because if we didn't,
169 * another process could get scheduled after the regs->msr
170 * test but before we have finished saving the FP registers
171 * to the thread_struct. That process could take over the
172 * FPU, and then when we get scheduled again we would store
173 * bogus values for the remaining FP registers.
176 if (tsk->thread.regs->msr & MSR_FP) {
178 * This should only ever be called for current or
179 * for a stopped child process. Since we save away
180 * the FP register state on context switch,
181 * there is something wrong if a stopped child appears
182 * to still have its FP state in the CPU registers.
184 BUG_ON(tsk != current);
190 EXPORT_SYMBOL_GPL(flush_fp_to_thread);
192 void enable_kernel_fp(void)
194 WARN_ON(preemptible());
196 msr_check_and_set(MSR_FP);
198 if (current->thread.regs && (current->thread.regs->msr & MSR_FP)) {
199 check_if_tm_restore_required(current);
200 __giveup_fpu(current);
203 EXPORT_SYMBOL(enable_kernel_fp);
205 static int restore_fp(struct task_struct *tsk) {
206 if (tsk->thread.load_fp) {
207 load_fp_state(¤t->thread.fp_state);
208 current->thread.load_fp++;
214 static int restore_fp(struct task_struct *tsk) { return 0; }
215 #endif /* CONFIG_PPC_FPU */
217 #ifdef CONFIG_ALTIVEC
218 #define loadvec(thr) ((thr).load_vec)
220 static void __giveup_altivec(struct task_struct *tsk)
223 tsk->thread.regs->msr &= ~MSR_VEC;
225 if (cpu_has_feature(CPU_FTR_VSX))
226 tsk->thread.regs->msr &= ~MSR_VSX;
230 void giveup_altivec(struct task_struct *tsk)
232 check_if_tm_restore_required(tsk);
234 msr_check_and_set(MSR_VEC);
235 __giveup_altivec(tsk);
236 msr_check_and_clear(MSR_VEC);
238 EXPORT_SYMBOL(giveup_altivec);
240 void enable_kernel_altivec(void)
242 WARN_ON(preemptible());
244 msr_check_and_set(MSR_VEC);
246 if (current->thread.regs && (current->thread.regs->msr & MSR_VEC)) {
247 check_if_tm_restore_required(current);
248 __giveup_altivec(current);
251 EXPORT_SYMBOL(enable_kernel_altivec);
254 * Make sure the VMX/Altivec register state in the
255 * the thread_struct is up to date for task tsk.
257 void flush_altivec_to_thread(struct task_struct *tsk)
259 if (tsk->thread.regs) {
261 if (tsk->thread.regs->msr & MSR_VEC) {
262 BUG_ON(tsk != current);
268 EXPORT_SYMBOL_GPL(flush_altivec_to_thread);
270 static int restore_altivec(struct task_struct *tsk)
272 if (cpu_has_feature(CPU_FTR_ALTIVEC) && tsk->thread.load_vec) {
273 load_vr_state(&tsk->thread.vr_state);
274 tsk->thread.used_vr = 1;
275 tsk->thread.load_vec++;
282 #define loadvec(thr) 0
283 static inline int restore_altivec(struct task_struct *tsk) { return 0; }
284 #endif /* CONFIG_ALTIVEC */
287 static void __giveup_vsx(struct task_struct *tsk)
289 if (tsk->thread.regs->msr & MSR_FP)
291 if (tsk->thread.regs->msr & MSR_VEC)
292 __giveup_altivec(tsk);
293 tsk->thread.regs->msr &= ~MSR_VSX;
296 static void giveup_vsx(struct task_struct *tsk)
298 check_if_tm_restore_required(tsk);
300 msr_check_and_set(MSR_FP|MSR_VEC|MSR_VSX);
302 msr_check_and_clear(MSR_FP|MSR_VEC|MSR_VSX);
305 static void save_vsx(struct task_struct *tsk)
307 if (tsk->thread.regs->msr & MSR_FP)
309 if (tsk->thread.regs->msr & MSR_VEC)
313 void enable_kernel_vsx(void)
315 WARN_ON(preemptible());
317 msr_check_and_set(MSR_FP|MSR_VEC|MSR_VSX);
319 if (current->thread.regs && (current->thread.regs->msr & MSR_VSX)) {
320 check_if_tm_restore_required(current);
321 if (current->thread.regs->msr & MSR_FP)
322 __giveup_fpu(current);
323 if (current->thread.regs->msr & MSR_VEC)
324 __giveup_altivec(current);
325 __giveup_vsx(current);
328 EXPORT_SYMBOL(enable_kernel_vsx);
330 void flush_vsx_to_thread(struct task_struct *tsk)
332 if (tsk->thread.regs) {
334 if (tsk->thread.regs->msr & MSR_VSX) {
335 BUG_ON(tsk != current);
341 EXPORT_SYMBOL_GPL(flush_vsx_to_thread);
343 static int restore_vsx(struct task_struct *tsk)
345 if (cpu_has_feature(CPU_FTR_VSX)) {
346 tsk->thread.used_vsr = 1;
353 static inline int restore_vsx(struct task_struct *tsk) { return 0; }
354 static inline void save_vsx(struct task_struct *tsk) { }
355 #endif /* CONFIG_VSX */
358 void giveup_spe(struct task_struct *tsk)
360 check_if_tm_restore_required(tsk);
362 msr_check_and_set(MSR_SPE);
364 msr_check_and_clear(MSR_SPE);
366 EXPORT_SYMBOL(giveup_spe);
368 void enable_kernel_spe(void)
370 WARN_ON(preemptible());
372 msr_check_and_set(MSR_SPE);
374 if (current->thread.regs && (current->thread.regs->msr & MSR_SPE)) {
375 check_if_tm_restore_required(current);
376 __giveup_spe(current);
379 EXPORT_SYMBOL(enable_kernel_spe);
381 void flush_spe_to_thread(struct task_struct *tsk)
383 if (tsk->thread.regs) {
385 if (tsk->thread.regs->msr & MSR_SPE) {
386 BUG_ON(tsk != current);
387 tsk->thread.spefscr = mfspr(SPRN_SPEFSCR);
393 #endif /* CONFIG_SPE */
395 static unsigned long msr_all_available;
397 static int __init init_msr_all_available(void)
399 #ifdef CONFIG_PPC_FPU
400 msr_all_available |= MSR_FP;
402 #ifdef CONFIG_ALTIVEC
403 if (cpu_has_feature(CPU_FTR_ALTIVEC))
404 msr_all_available |= MSR_VEC;
407 if (cpu_has_feature(CPU_FTR_VSX))
408 msr_all_available |= MSR_VSX;
411 if (cpu_has_feature(CPU_FTR_SPE))
412 msr_all_available |= MSR_SPE;
417 early_initcall(init_msr_all_available);
419 void giveup_all(struct task_struct *tsk)
421 unsigned long usermsr;
423 if (!tsk->thread.regs)
426 usermsr = tsk->thread.regs->msr;
428 if ((usermsr & msr_all_available) == 0)
431 msr_check_and_set(msr_all_available);
433 #ifdef CONFIG_PPC_FPU
434 if (usermsr & MSR_FP)
437 #ifdef CONFIG_ALTIVEC
438 if (usermsr & MSR_VEC)
439 __giveup_altivec(tsk);
442 if (usermsr & MSR_VSX)
446 if (usermsr & MSR_SPE)
450 msr_check_and_clear(msr_all_available);
452 EXPORT_SYMBOL(giveup_all);
454 void restore_math(struct pt_regs *regs)
458 if (!current->thread.load_fp && !loadvec(current->thread))
462 msr_check_and_set(msr_all_available);
465 * Only reload if the bit is not set in the user MSR, the bit BEING set
466 * indicates that the registers are hot
468 if ((!(msr & MSR_FP)) && restore_fp(current))
469 msr |= MSR_FP | current->thread.fpexc_mode;
471 if ((!(msr & MSR_VEC)) && restore_altivec(current))
474 if ((msr & (MSR_FP | MSR_VEC)) == (MSR_FP | MSR_VEC) &&
475 restore_vsx(current)) {
479 msr_check_and_clear(msr_all_available);
484 void save_all(struct task_struct *tsk)
486 unsigned long usermsr;
488 if (!tsk->thread.regs)
491 usermsr = tsk->thread.regs->msr;
493 if ((usermsr & msr_all_available) == 0)
496 msr_check_and_set(msr_all_available);
499 * Saving the way the register space is in hardware, save_vsx boils
500 * down to a save_fpu() and save_altivec()
502 if (usermsr & MSR_VSX) {
505 if (usermsr & MSR_FP)
508 if (usermsr & MSR_VEC)
512 if (usermsr & MSR_SPE)
515 msr_check_and_clear(msr_all_available);
518 void flush_all_to_thread(struct task_struct *tsk)
520 if (tsk->thread.regs) {
522 BUG_ON(tsk != current);
526 if (tsk->thread.regs->msr & MSR_SPE)
527 tsk->thread.spefscr = mfspr(SPRN_SPEFSCR);
533 EXPORT_SYMBOL(flush_all_to_thread);
535 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
536 void do_send_trap(struct pt_regs *regs, unsigned long address,
537 unsigned long error_code, int signal_code, int breakpt)
541 current->thread.trap_nr = signal_code;
542 if (notify_die(DIE_DABR_MATCH, "dabr_match", regs, error_code,
543 11, SIGSEGV) == NOTIFY_STOP)
546 /* Deliver the signal to userspace */
547 info.si_signo = SIGTRAP;
548 info.si_errno = breakpt; /* breakpoint or watchpoint id */
549 info.si_code = signal_code;
550 info.si_addr = (void __user *)address;
551 force_sig_info(SIGTRAP, &info, current);
553 #else /* !CONFIG_PPC_ADV_DEBUG_REGS */
554 void do_break (struct pt_regs *regs, unsigned long address,
555 unsigned long error_code)
559 current->thread.trap_nr = TRAP_HWBKPT;
560 if (notify_die(DIE_DABR_MATCH, "dabr_match", regs, error_code,
561 11, SIGSEGV) == NOTIFY_STOP)
564 if (debugger_break_match(regs))
567 /* Clear the breakpoint */
568 hw_breakpoint_disable();
570 /* Deliver the signal to userspace */
571 info.si_signo = SIGTRAP;
573 info.si_code = TRAP_HWBKPT;
574 info.si_addr = (void __user *)address;
575 force_sig_info(SIGTRAP, &info, current);
577 #endif /* CONFIG_PPC_ADV_DEBUG_REGS */
579 static DEFINE_PER_CPU(struct arch_hw_breakpoint, current_brk);
581 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
583 * Set the debug registers back to their default "safe" values.
585 static void set_debug_reg_defaults(struct thread_struct *thread)
587 thread->debug.iac1 = thread->debug.iac2 = 0;
588 #if CONFIG_PPC_ADV_DEBUG_IACS > 2
589 thread->debug.iac3 = thread->debug.iac4 = 0;
591 thread->debug.dac1 = thread->debug.dac2 = 0;
592 #if CONFIG_PPC_ADV_DEBUG_DVCS > 0
593 thread->debug.dvc1 = thread->debug.dvc2 = 0;
595 thread->debug.dbcr0 = 0;
598 * Force User/Supervisor bits to b11 (user-only MSR[PR]=1)
600 thread->debug.dbcr1 = DBCR1_IAC1US | DBCR1_IAC2US |
601 DBCR1_IAC3US | DBCR1_IAC4US;
603 * Force Data Address Compare User/Supervisor bits to be User-only
604 * (0b11 MSR[PR]=1) and set all other bits in DBCR2 register to be 0.
606 thread->debug.dbcr2 = DBCR2_DAC1US | DBCR2_DAC2US;
608 thread->debug.dbcr1 = 0;
612 static void prime_debug_regs(struct debug_reg *debug)
615 * We could have inherited MSR_DE from userspace, since
616 * it doesn't get cleared on exception entry. Make sure
617 * MSR_DE is clear before we enable any debug events.
619 mtmsr(mfmsr() & ~MSR_DE);
621 mtspr(SPRN_IAC1, debug->iac1);
622 mtspr(SPRN_IAC2, debug->iac2);
623 #if CONFIG_PPC_ADV_DEBUG_IACS > 2
624 mtspr(SPRN_IAC3, debug->iac3);
625 mtspr(SPRN_IAC4, debug->iac4);
627 mtspr(SPRN_DAC1, debug->dac1);
628 mtspr(SPRN_DAC2, debug->dac2);
629 #if CONFIG_PPC_ADV_DEBUG_DVCS > 0
630 mtspr(SPRN_DVC1, debug->dvc1);
631 mtspr(SPRN_DVC2, debug->dvc2);
633 mtspr(SPRN_DBCR0, debug->dbcr0);
634 mtspr(SPRN_DBCR1, debug->dbcr1);
636 mtspr(SPRN_DBCR2, debug->dbcr2);
640 * Unless neither the old or new thread are making use of the
641 * debug registers, set the debug registers from the values
642 * stored in the new thread.
644 void switch_booke_debug_regs(struct debug_reg *new_debug)
646 if ((current->thread.debug.dbcr0 & DBCR0_IDM)
647 || (new_debug->dbcr0 & DBCR0_IDM))
648 prime_debug_regs(new_debug);
650 EXPORT_SYMBOL_GPL(switch_booke_debug_regs);
651 #else /* !CONFIG_PPC_ADV_DEBUG_REGS */
652 #ifndef CONFIG_HAVE_HW_BREAKPOINT
653 static void set_debug_reg_defaults(struct thread_struct *thread)
655 thread->hw_brk.address = 0;
656 thread->hw_brk.type = 0;
657 set_breakpoint(&thread->hw_brk);
659 #endif /* !CONFIG_HAVE_HW_BREAKPOINT */
660 #endif /* CONFIG_PPC_ADV_DEBUG_REGS */
662 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
663 static inline int __set_dabr(unsigned long dabr, unsigned long dabrx)
665 mtspr(SPRN_DAC1, dabr);
666 #ifdef CONFIG_PPC_47x
671 #elif defined(CONFIG_PPC_BOOK3S)
672 static inline int __set_dabr(unsigned long dabr, unsigned long dabrx)
674 mtspr(SPRN_DABR, dabr);
675 if (cpu_has_feature(CPU_FTR_DABRX))
676 mtspr(SPRN_DABRX, dabrx);
680 static inline int __set_dabr(unsigned long dabr, unsigned long dabrx)
686 static inline int set_dabr(struct arch_hw_breakpoint *brk)
688 unsigned long dabr, dabrx;
690 dabr = brk->address | (brk->type & HW_BRK_TYPE_DABR);
691 dabrx = ((brk->type >> 3) & 0x7);
694 return ppc_md.set_dabr(dabr, dabrx);
696 return __set_dabr(dabr, dabrx);
699 static inline int set_dawr(struct arch_hw_breakpoint *brk)
701 unsigned long dawr, dawrx, mrd;
705 dawrx = (brk->type & (HW_BRK_TYPE_READ | HW_BRK_TYPE_WRITE)) \
706 << (63 - 58); //* read/write bits */
707 dawrx |= ((brk->type & (HW_BRK_TYPE_TRANSLATE)) >> 2) \
708 << (63 - 59); //* translate */
709 dawrx |= (brk->type & (HW_BRK_TYPE_PRIV_ALL)) \
710 >> 3; //* PRIM bits */
711 /* dawr length is stored in field MDR bits 48:53. Matches range in
712 doublewords (64 bits) baised by -1 eg. 0b000000=1DW and
714 brk->len is in bytes.
715 This aligns up to double word size, shifts and does the bias.
717 mrd = ((brk->len + 7) >> 3) - 1;
718 dawrx |= (mrd & 0x3f) << (63 - 53);
721 return ppc_md.set_dawr(dawr, dawrx);
722 mtspr(SPRN_DAWR, dawr);
723 mtspr(SPRN_DAWRX, dawrx);
727 void __set_breakpoint(struct arch_hw_breakpoint *brk)
729 memcpy(this_cpu_ptr(¤t_brk), brk, sizeof(*brk));
731 if (cpu_has_feature(CPU_FTR_DAWR))
737 void set_breakpoint(struct arch_hw_breakpoint *brk)
740 __set_breakpoint(brk);
745 DEFINE_PER_CPU(struct cpu_usage, cpu_usage_array);
748 static inline bool hw_brk_match(struct arch_hw_breakpoint *a,
749 struct arch_hw_breakpoint *b)
751 if (a->address != b->address)
753 if (a->type != b->type)
755 if (a->len != b->len)
760 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
761 static void tm_reclaim_thread(struct thread_struct *thr,
762 struct thread_info *ti, uint8_t cause)
764 unsigned long msr_diff = 0;
767 * If FP/VSX registers have been already saved to the
768 * thread_struct, move them to the transact_fp array.
769 * We clear the TIF_RESTORE_TM bit since after the reclaim
770 * the thread will no longer be transactional.
772 if (test_ti_thread_flag(ti, TIF_RESTORE_TM)) {
773 msr_diff = thr->ckpt_regs.msr & ~thr->regs->msr;
774 if (msr_diff & MSR_FP)
775 memcpy(&thr->transact_fp, &thr->fp_state,
776 sizeof(struct thread_fp_state));
777 if (msr_diff & MSR_VEC)
778 memcpy(&thr->transact_vr, &thr->vr_state,
779 sizeof(struct thread_vr_state));
780 clear_ti_thread_flag(ti, TIF_RESTORE_TM);
781 msr_diff &= MSR_FP | MSR_VEC | MSR_VSX | MSR_FE0 | MSR_FE1;
785 * Use the current MSR TM suspended bit to track if we have
786 * checkpointed state outstanding.
787 * On signal delivery, we'd normally reclaim the checkpointed
788 * state to obtain stack pointer (see:get_tm_stackpointer()).
789 * This will then directly return to userspace without going
790 * through __switch_to(). However, if the stack frame is bad,
791 * we need to exit this thread which calls __switch_to() which
792 * will again attempt to reclaim the already saved tm state.
793 * Hence we need to check that we've not already reclaimed
795 * We do this using the current MSR, rather tracking it in
796 * some specific thread_struct bit, as it has the additional
797 * benifit of checking for a potential TM bad thing exception.
799 if (!MSR_TM_SUSPENDED(mfmsr()))
802 tm_reclaim(thr, thr->regs->msr, cause);
804 /* Having done the reclaim, we now have the checkpointed
805 * FP/VSX values in the registers. These might be valid
806 * even if we have previously called enable_kernel_fp() or
807 * flush_fp_to_thread(), so update thr->regs->msr to
808 * indicate their current validity.
810 thr->regs->msr |= msr_diff;
813 void tm_reclaim_current(uint8_t cause)
816 tm_reclaim_thread(¤t->thread, current_thread_info(), cause);
819 static inline void tm_reclaim_task(struct task_struct *tsk)
821 /* We have to work out if we're switching from/to a task that's in the
822 * middle of a transaction.
824 * In switching we need to maintain a 2nd register state as
825 * oldtask->thread.ckpt_regs. We tm_reclaim(oldproc); this saves the
826 * checkpointed (tbegin) state in ckpt_regs and saves the transactional
827 * (current) FPRs into oldtask->thread.transact_fpr[].
829 * We also context switch (save) TFHAR/TEXASR/TFIAR in here.
831 struct thread_struct *thr = &tsk->thread;
836 if (!MSR_TM_ACTIVE(thr->regs->msr))
837 goto out_and_saveregs;
839 /* Stash the original thread MSR, as giveup_fpu et al will
840 * modify it. We hold onto it to see whether the task used
841 * FP & vector regs. If the TIF_RESTORE_TM flag is set,
842 * ckpt_regs.msr is already set.
844 if (!test_ti_thread_flag(task_thread_info(tsk), TIF_RESTORE_TM))
845 thr->ckpt_regs.msr = thr->regs->msr;
847 TM_DEBUG("--- tm_reclaim on pid %d (NIP=%lx, "
848 "ccr=%lx, msr=%lx, trap=%lx)\n",
849 tsk->pid, thr->regs->nip,
850 thr->regs->ccr, thr->regs->msr,
853 tm_reclaim_thread(thr, task_thread_info(tsk), TM_CAUSE_RESCHED);
855 TM_DEBUG("--- tm_reclaim on pid %d complete\n",
859 /* Always save the regs here, even if a transaction's not active.
860 * This context-switches a thread's TM info SPRs. We do it here to
861 * be consistent with the restore path (in recheckpoint) which
862 * cannot happen later in _switch().
867 extern void __tm_recheckpoint(struct thread_struct *thread,
868 unsigned long orig_msr);
870 void tm_recheckpoint(struct thread_struct *thread,
871 unsigned long orig_msr)
875 /* We really can't be interrupted here as the TEXASR registers can't
876 * change and later in the trecheckpoint code, we have a userspace R1.
877 * So let's hard disable over this region.
879 local_irq_save(flags);
882 /* The TM SPRs are restored here, so that TEXASR.FS can be set
883 * before the trecheckpoint and no explosion occurs.
885 tm_restore_sprs(thread);
887 __tm_recheckpoint(thread, orig_msr);
889 local_irq_restore(flags);
892 static inline void tm_recheckpoint_new_task(struct task_struct *new)
896 if (!cpu_has_feature(CPU_FTR_TM))
899 /* Recheckpoint the registers of the thread we're about to switch to.
901 * If the task was using FP, we non-lazily reload both the original and
902 * the speculative FP register states. This is because the kernel
903 * doesn't see if/when a TM rollback occurs, so if we take an FP
904 * unavoidable later, we are unable to determine which set of FP regs
905 * need to be restored.
907 if (!new->thread.regs)
910 if (!MSR_TM_ACTIVE(new->thread.regs->msr)){
911 tm_restore_sprs(&new->thread);
914 msr = new->thread.ckpt_regs.msr;
915 /* Recheckpoint to restore original checkpointed register state. */
916 TM_DEBUG("*** tm_recheckpoint of pid %d "
917 "(new->msr 0x%lx, new->origmsr 0x%lx)\n",
918 new->pid, new->thread.regs->msr, msr);
920 /* This loads the checkpointed FP/VEC state, if used */
921 tm_recheckpoint(&new->thread, msr);
923 /* This loads the speculative FP/VEC state, if used */
925 do_load_up_transact_fpu(&new->thread);
926 new->thread.regs->msr |=
927 (MSR_FP | new->thread.fpexc_mode);
929 #ifdef CONFIG_ALTIVEC
931 do_load_up_transact_altivec(&new->thread);
932 new->thread.regs->msr |= MSR_VEC;
935 /* We may as well turn on VSX too since all the state is restored now */
937 new->thread.regs->msr |= MSR_VSX;
939 TM_DEBUG("*** tm_recheckpoint of pid %d complete "
940 "(kernel msr 0x%lx)\n",
944 static inline void __switch_to_tm(struct task_struct *prev)
946 if (cpu_has_feature(CPU_FTR_TM)) {
948 tm_reclaim_task(prev);
953 * This is called if we are on the way out to userspace and the
954 * TIF_RESTORE_TM flag is set. It checks if we need to reload
955 * FP and/or vector state and does so if necessary.
956 * If userspace is inside a transaction (whether active or
957 * suspended) and FP/VMX/VSX instructions have ever been enabled
958 * inside that transaction, then we have to keep them enabled
959 * and keep the FP/VMX/VSX state loaded while ever the transaction
960 * continues. The reason is that if we didn't, and subsequently
961 * got a FP/VMX/VSX unavailable interrupt inside a transaction,
962 * we don't know whether it's the same transaction, and thus we
963 * don't know which of the checkpointed state and the transactional
966 void restore_tm_state(struct pt_regs *regs)
968 unsigned long msr_diff;
970 clear_thread_flag(TIF_RESTORE_TM);
971 if (!MSR_TM_ACTIVE(regs->msr))
974 msr_diff = current->thread.ckpt_regs.msr & ~regs->msr;
975 msr_diff &= MSR_FP | MSR_VEC | MSR_VSX;
979 regs->msr |= msr_diff;
983 #define tm_recheckpoint_new_task(new)
984 #define __switch_to_tm(prev)
985 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
987 static inline void save_sprs(struct thread_struct *t)
989 #ifdef CONFIG_ALTIVEC
990 if (cpu_has_feature(CPU_FTR_ALTIVEC))
991 t->vrsave = mfspr(SPRN_VRSAVE);
993 #ifdef CONFIG_PPC_BOOK3S_64
994 if (cpu_has_feature(CPU_FTR_DSCR))
995 t->dscr = mfspr(SPRN_DSCR);
997 if (cpu_has_feature(CPU_FTR_ARCH_207S)) {
998 t->bescr = mfspr(SPRN_BESCR);
999 t->ebbhr = mfspr(SPRN_EBBHR);
1000 t->ebbrr = mfspr(SPRN_EBBRR);
1002 t->fscr = mfspr(SPRN_FSCR);
1005 * Note that the TAR is not available for use in the kernel.
1006 * (To provide this, the TAR should be backed up/restored on
1007 * exception entry/exit instead, and be in pt_regs. FIXME,
1008 * this should be in pt_regs anyway (for debug).)
1010 t->tar = mfspr(SPRN_TAR);
1015 static inline void restore_sprs(struct thread_struct *old_thread,
1016 struct thread_struct *new_thread)
1018 #ifdef CONFIG_ALTIVEC
1019 if (cpu_has_feature(CPU_FTR_ALTIVEC) &&
1020 old_thread->vrsave != new_thread->vrsave)
1021 mtspr(SPRN_VRSAVE, new_thread->vrsave);
1023 #ifdef CONFIG_PPC_BOOK3S_64
1024 if (cpu_has_feature(CPU_FTR_DSCR)) {
1025 u64 dscr = get_paca()->dscr_default;
1026 u64 fscr = old_thread->fscr & ~FSCR_DSCR;
1028 if (new_thread->dscr_inherit) {
1029 dscr = new_thread->dscr;
1033 if (old_thread->dscr != dscr)
1034 mtspr(SPRN_DSCR, dscr);
1036 if (old_thread->fscr != fscr)
1037 mtspr(SPRN_FSCR, fscr);
1040 if (cpu_has_feature(CPU_FTR_ARCH_207S)) {
1041 if (old_thread->bescr != new_thread->bescr)
1042 mtspr(SPRN_BESCR, new_thread->bescr);
1043 if (old_thread->ebbhr != new_thread->ebbhr)
1044 mtspr(SPRN_EBBHR, new_thread->ebbhr);
1045 if (old_thread->ebbrr != new_thread->ebbrr)
1046 mtspr(SPRN_EBBRR, new_thread->ebbrr);
1048 if (old_thread->tar != new_thread->tar)
1049 mtspr(SPRN_TAR, new_thread->tar);
1054 struct task_struct *__switch_to(struct task_struct *prev,
1055 struct task_struct *new)
1057 struct thread_struct *new_thread, *old_thread;
1058 struct task_struct *last;
1059 #ifdef CONFIG_PPC_BOOK3S_64
1060 struct ppc64_tlb_batch *batch;
1063 new_thread = &new->thread;
1064 old_thread = ¤t->thread;
1066 WARN_ON(!irqs_disabled());
1070 * Collect processor utilization data per process
1072 if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
1073 struct cpu_usage *cu = this_cpu_ptr(&cpu_usage_array);
1074 long unsigned start_tb, current_tb;
1075 start_tb = old_thread->start_tb;
1076 cu->current_tb = current_tb = mfspr(SPRN_PURR);
1077 old_thread->accum_tb += (current_tb - start_tb);
1078 new_thread->start_tb = current_tb;
1080 #endif /* CONFIG_PPC64 */
1082 #ifdef CONFIG_PPC_STD_MMU_64
1083 batch = this_cpu_ptr(&ppc64_tlb_batch);
1084 if (batch->active) {
1085 current_thread_info()->local_flags |= _TLF_LAZY_MMU;
1087 __flush_tlb_pending(batch);
1090 #endif /* CONFIG_PPC_STD_MMU_64 */
1092 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
1093 switch_booke_debug_regs(&new->thread.debug);
1096 * For PPC_BOOK3S_64, we use the hw-breakpoint interfaces that would
1099 #ifndef CONFIG_HAVE_HW_BREAKPOINT
1100 if (unlikely(!hw_brk_match(this_cpu_ptr(¤t_brk), &new->thread.hw_brk)))
1101 __set_breakpoint(&new->thread.hw_brk);
1102 #endif /* CONFIG_HAVE_HW_BREAKPOINT */
1106 * We need to save SPRs before treclaim/trecheckpoint as these will
1107 * change a number of them.
1109 save_sprs(&prev->thread);
1111 __switch_to_tm(prev);
1113 /* Save FPU, Altivec, VSX and SPE state */
1117 * We can't take a PMU exception inside _switch() since there is a
1118 * window where the kernel stack SLB and the kernel stack are out
1119 * of sync. Hard disable here.
1123 tm_recheckpoint_new_task(new);
1126 * Call restore_sprs() before calling _switch(). If we move it after
1127 * _switch() then we miss out on calling it for new tasks. The reason
1128 * for this is we manually create a stack frame for new tasks that
1129 * directly returns through ret_from_fork() or
1130 * ret_from_kernel_thread(). See copy_thread() for details.
1132 restore_sprs(old_thread, new_thread);
1134 last = _switch(old_thread, new_thread);
1136 #ifdef CONFIG_PPC_STD_MMU_64
1137 if (current_thread_info()->local_flags & _TLF_LAZY_MMU) {
1138 current_thread_info()->local_flags &= ~_TLF_LAZY_MMU;
1139 batch = this_cpu_ptr(&ppc64_tlb_batch);
1143 if (current_thread_info()->task->thread.regs)
1144 restore_math(current_thread_info()->task->thread.regs);
1145 #endif /* CONFIG_PPC_STD_MMU_64 */
1150 static int instructions_to_print = 16;
1152 static void show_instructions(struct pt_regs *regs)
1155 unsigned long pc = regs->nip - (instructions_to_print * 3 / 4 *
1158 printk("Instruction dump:");
1160 for (i = 0; i < instructions_to_print; i++) {
1166 #if !defined(CONFIG_BOOKE)
1167 /* If executing with the IMMU off, adjust pc rather
1168 * than print XXXXXXXX.
1170 if (!(regs->msr & MSR_IR))
1171 pc = (unsigned long)phys_to_virt(pc);
1174 if (!__kernel_text_address(pc) ||
1175 probe_kernel_address((unsigned int __user *)pc, instr)) {
1176 printk(KERN_CONT "XXXXXXXX ");
1178 if (regs->nip == pc)
1179 printk(KERN_CONT "<%08x> ", instr);
1181 printk(KERN_CONT "%08x ", instr);
1195 static struct regbit msr_bits[] = {
1196 #if defined(CONFIG_PPC64) && !defined(CONFIG_BOOKE)
1218 #ifndef CONFIG_BOOKE
1225 static void print_bits(unsigned long val, struct regbit *bits, const char *sep)
1229 for (; bits->bit; ++bits)
1230 if (val & bits->bit) {
1231 printk("%s%s", s, bits->name);
1236 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1237 static struct regbit msr_tm_bits[] = {
1244 static void print_tm_bits(unsigned long val)
1247 * This only prints something if at least one of the TM bit is set.
1248 * Inside the TM[], the output means:
1249 * E: Enabled (bit 32)
1250 * S: Suspended (bit 33)
1251 * T: Transactional (bit 34)
1253 if (val & (MSR_TM | MSR_TS_S | MSR_TS_T)) {
1255 print_bits(val, msr_tm_bits, "");
1260 static void print_tm_bits(unsigned long val) {}
1263 static void print_msr_bits(unsigned long val)
1266 print_bits(val, msr_bits, ",");
1272 #define REG "%016lx"
1273 #define REGS_PER_LINE 4
1274 #define LAST_VOLATILE 13
1277 #define REGS_PER_LINE 8
1278 #define LAST_VOLATILE 12
1281 void show_regs(struct pt_regs * regs)
1285 show_regs_print_info(KERN_DEFAULT);
1287 printk("NIP: "REG" LR: "REG" CTR: "REG"\n",
1288 regs->nip, regs->link, regs->ctr);
1289 printk("REGS: %p TRAP: %04lx %s (%s)\n",
1290 regs, regs->trap, print_tainted(), init_utsname()->release);
1291 printk("MSR: "REG" ", regs->msr);
1292 print_msr_bits(regs->msr);
1293 printk(" CR: %08lx XER: %08lx\n", regs->ccr, regs->xer);
1295 if ((regs->trap != 0xc00) && cpu_has_feature(CPU_FTR_CFAR))
1296 printk("CFAR: "REG" ", regs->orig_gpr3);
1297 if (trap == 0x200 || trap == 0x300 || trap == 0x600)
1298 #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
1299 printk("DEAR: "REG" ESR: "REG" ", regs->dar, regs->dsisr);
1301 printk("DAR: "REG" DSISR: %08lx ", regs->dar, regs->dsisr);
1304 printk("SOFTE: %ld ", regs->softe);
1306 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1307 if (MSR_TM_ACTIVE(regs->msr))
1308 printk("\nPACATMSCRATCH: %016llx ", get_paca()->tm_scratch);
1311 for (i = 0; i < 32; i++) {
1312 if ((i % REGS_PER_LINE) == 0)
1313 printk("\nGPR%02d: ", i);
1314 printk(REG " ", regs->gpr[i]);
1315 if (i == LAST_VOLATILE && !FULL_REGS(regs))
1319 #ifdef CONFIG_KALLSYMS
1321 * Lookup NIP late so we have the best change of getting the
1322 * above info out without failing
1324 printk("NIP ["REG"] %pS\n", regs->nip, (void *)regs->nip);
1325 printk("LR ["REG"] %pS\n", regs->link, (void *)regs->link);
1327 show_stack(current, (unsigned long *) regs->gpr[1]);
1328 if (!user_mode(regs))
1329 show_instructions(regs);
1332 void flush_thread(void)
1334 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1335 flush_ptrace_hw_breakpoint(current);
1336 #else /* CONFIG_HAVE_HW_BREAKPOINT */
1337 set_debug_reg_defaults(¤t->thread);
1338 #endif /* CONFIG_HAVE_HW_BREAKPOINT */
1342 release_thread(struct task_struct *t)
1347 * this gets called so that we can store coprocessor state into memory and
1348 * copy the current task into the new thread.
1350 int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
1352 flush_all_to_thread(src);
1354 * Flush TM state out so we can copy it. __switch_to_tm() does this
1355 * flush but it removes the checkpointed state from the current CPU and
1356 * transitions the CPU out of TM mode. Hence we need to call
1357 * tm_recheckpoint_new_task() (on the same task) to restore the
1358 * checkpointed state back and the TM mode.
1360 __switch_to_tm(src);
1361 tm_recheckpoint_new_task(src);
1365 clear_task_ebb(dst);
1370 static void setup_ksp_vsid(struct task_struct *p, unsigned long sp)
1372 #ifdef CONFIG_PPC_STD_MMU_64
1373 unsigned long sp_vsid;
1374 unsigned long llp = mmu_psize_defs[mmu_linear_psize].sllp;
1376 if (radix_enabled())
1379 if (mmu_has_feature(MMU_FTR_1T_SEGMENT))
1380 sp_vsid = get_kernel_vsid(sp, MMU_SEGSIZE_1T)
1381 << SLB_VSID_SHIFT_1T;
1383 sp_vsid = get_kernel_vsid(sp, MMU_SEGSIZE_256M)
1385 sp_vsid |= SLB_VSID_KERNEL | llp;
1386 p->thread.ksp_vsid = sp_vsid;
1395 * Copy architecture-specific thread state
1397 int copy_thread(unsigned long clone_flags, unsigned long usp,
1398 unsigned long kthread_arg, struct task_struct *p)
1400 struct pt_regs *childregs, *kregs;
1401 extern void ret_from_fork(void);
1402 extern void ret_from_kernel_thread(void);
1404 unsigned long sp = (unsigned long)task_stack_page(p) + THREAD_SIZE;
1405 struct thread_info *ti = task_thread_info(p);
1407 klp_init_thread_info(ti);
1409 /* Copy registers */
1410 sp -= sizeof(struct pt_regs);
1411 childregs = (struct pt_regs *) sp;
1412 if (unlikely(p->flags & PF_KTHREAD)) {
1414 memset(childregs, 0, sizeof(struct pt_regs));
1415 childregs->gpr[1] = sp + sizeof(struct pt_regs);
1418 childregs->gpr[14] = ppc_function_entry((void *)usp);
1420 clear_tsk_thread_flag(p, TIF_32BIT);
1421 childregs->softe = 1;
1423 childregs->gpr[15] = kthread_arg;
1424 p->thread.regs = NULL; /* no user register state */
1425 ti->flags |= _TIF_RESTOREALL;
1426 f = ret_from_kernel_thread;
1429 struct pt_regs *regs = current_pt_regs();
1430 CHECK_FULL_REGS(regs);
1433 childregs->gpr[1] = usp;
1434 p->thread.regs = childregs;
1435 childregs->gpr[3] = 0; /* Result from fork() */
1436 if (clone_flags & CLONE_SETTLS) {
1438 if (!is_32bit_task())
1439 childregs->gpr[13] = childregs->gpr[6];
1442 childregs->gpr[2] = childregs->gpr[6];
1447 childregs->msr &= ~(MSR_FP|MSR_VEC|MSR_VSX);
1448 sp -= STACK_FRAME_OVERHEAD;
1451 * The way this works is that at some point in the future
1452 * some task will call _switch to switch to the new task.
1453 * That will pop off the stack frame created below and start
1454 * the new task running at ret_from_fork. The new task will
1455 * do some house keeping and then return from the fork or clone
1456 * system call, using the stack frame created above.
1458 ((unsigned long *)sp)[0] = 0;
1459 sp -= sizeof(struct pt_regs);
1460 kregs = (struct pt_regs *) sp;
1461 sp -= STACK_FRAME_OVERHEAD;
1464 p->thread.ksp_limit = (unsigned long)task_stack_page(p) +
1465 _ALIGN_UP(sizeof(struct thread_info), 16);
1467 #ifdef CONFIG_HAVE_HW_BREAKPOINT
1468 p->thread.ptrace_bps[0] = NULL;
1471 p->thread.fp_save_area = NULL;
1472 #ifdef CONFIG_ALTIVEC
1473 p->thread.vr_save_area = NULL;
1476 setup_ksp_vsid(p, sp);
1479 if (cpu_has_feature(CPU_FTR_DSCR)) {
1480 p->thread.dscr_inherit = current->thread.dscr_inherit;
1481 p->thread.dscr = mfspr(SPRN_DSCR);
1483 if (cpu_has_feature(CPU_FTR_HAS_PPR))
1484 p->thread.ppr = INIT_PPR;
1486 kregs->nip = ppc_function_entry(f);
1491 * Set up a thread for executing a new program
1493 void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp)
1496 unsigned long load_addr = regs->gpr[2]; /* saved by ELF_PLAT_INIT */
1500 * If we exec out of a kernel thread then thread.regs will not be
1503 if (!current->thread.regs) {
1504 struct pt_regs *regs = task_stack_page(current) + THREAD_SIZE;
1505 current->thread.regs = regs - 1;
1508 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1510 * Clear any transactional state, we're exec()ing. The cause is
1511 * not important as there will never be a recheckpoint so it's not
1514 if (MSR_TM_SUSPENDED(mfmsr()))
1515 tm_reclaim_current(0);
1518 memset(regs->gpr, 0, sizeof(regs->gpr));
1526 * We have just cleared all the nonvolatile GPRs, so make
1527 * FULL_REGS(regs) return true. This is necessary to allow
1528 * ptrace to examine the thread immediately after exec.
1535 regs->msr = MSR_USER;
1537 if (!is_32bit_task()) {
1538 unsigned long entry;
1540 if (is_elf2_task()) {
1541 /* Look ma, no function descriptors! */
1546 * The latest iteration of the ABI requires that when
1547 * calling a function (at its global entry point),
1548 * the caller must ensure r12 holds the entry point
1549 * address (so that the function can quickly
1550 * establish addressability).
1552 regs->gpr[12] = start;
1553 /* Make sure that's restored on entry to userspace. */
1554 set_thread_flag(TIF_RESTOREALL);
1558 /* start is a relocated pointer to the function
1559 * descriptor for the elf _start routine. The first
1560 * entry in the function descriptor is the entry
1561 * address of _start and the second entry is the TOC
1562 * value we need to use.
1564 __get_user(entry, (unsigned long __user *)start);
1565 __get_user(toc, (unsigned long __user *)start+1);
1567 /* Check whether the e_entry function descriptor entries
1568 * need to be relocated before we can use them.
1570 if (load_addr != 0) {
1577 regs->msr = MSR_USER64;
1581 regs->msr = MSR_USER32;
1585 current->thread.used_vsr = 0;
1587 memset(¤t->thread.fp_state, 0, sizeof(current->thread.fp_state));
1588 current->thread.fp_save_area = NULL;
1589 #ifdef CONFIG_ALTIVEC
1590 memset(¤t->thread.vr_state, 0, sizeof(current->thread.vr_state));
1591 current->thread.vr_state.vscr.u[3] = 0x00010000; /* Java mode disabled */
1592 current->thread.vr_save_area = NULL;
1593 current->thread.vrsave = 0;
1594 current->thread.used_vr = 0;
1595 #endif /* CONFIG_ALTIVEC */
1597 memset(current->thread.evr, 0, sizeof(current->thread.evr));
1598 current->thread.acc = 0;
1599 current->thread.spefscr = 0;
1600 current->thread.used_spe = 0;
1601 #endif /* CONFIG_SPE */
1602 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1603 if (cpu_has_feature(CPU_FTR_TM))
1604 regs->msr |= MSR_TM;
1605 current->thread.tm_tfhar = 0;
1606 current->thread.tm_texasr = 0;
1607 current->thread.tm_tfiar = 0;
1608 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
1610 EXPORT_SYMBOL(start_thread);
1612 #define PR_FP_ALL_EXCEPT (PR_FP_EXC_DIV | PR_FP_EXC_OVF | PR_FP_EXC_UND \
1613 | PR_FP_EXC_RES | PR_FP_EXC_INV)
1615 int set_fpexc_mode(struct task_struct *tsk, unsigned int val)
1617 struct pt_regs *regs = tsk->thread.regs;
1619 /* This is a bit hairy. If we are an SPE enabled processor
1620 * (have embedded fp) we store the IEEE exception enable flags in
1621 * fpexc_mode. fpexc_mode is also used for setting FP exception
1622 * mode (asyn, precise, disabled) for 'Classic' FP. */
1623 if (val & PR_FP_EXC_SW_ENABLE) {
1625 if (cpu_has_feature(CPU_FTR_SPE)) {
1627 * When the sticky exception bits are set
1628 * directly by userspace, it must call prctl
1629 * with PR_GET_FPEXC (with PR_FP_EXC_SW_ENABLE
1630 * in the existing prctl settings) or
1631 * PR_SET_FPEXC (with PR_FP_EXC_SW_ENABLE in
1632 * the bits being set). <fenv.h> functions
1633 * saving and restoring the whole
1634 * floating-point environment need to do so
1635 * anyway to restore the prctl settings from
1636 * the saved environment.
1638 tsk->thread.spefscr_last = mfspr(SPRN_SPEFSCR);
1639 tsk->thread.fpexc_mode = val &
1640 (PR_FP_EXC_SW_ENABLE | PR_FP_ALL_EXCEPT);
1650 /* on a CONFIG_SPE this does not hurt us. The bits that
1651 * __pack_fe01 use do not overlap with bits used for
1652 * PR_FP_EXC_SW_ENABLE. Additionally, the MSR[FE0,FE1] bits
1653 * on CONFIG_SPE implementations are reserved so writing to
1654 * them does not change anything */
1655 if (val > PR_FP_EXC_PRECISE)
1657 tsk->thread.fpexc_mode = __pack_fe01(val);
1658 if (regs != NULL && (regs->msr & MSR_FP) != 0)
1659 regs->msr = (regs->msr & ~(MSR_FE0|MSR_FE1))
1660 | tsk->thread.fpexc_mode;
1664 int get_fpexc_mode(struct task_struct *tsk, unsigned long adr)
1668 if (tsk->thread.fpexc_mode & PR_FP_EXC_SW_ENABLE)
1670 if (cpu_has_feature(CPU_FTR_SPE)) {
1672 * When the sticky exception bits are set
1673 * directly by userspace, it must call prctl
1674 * with PR_GET_FPEXC (with PR_FP_EXC_SW_ENABLE
1675 * in the existing prctl settings) or
1676 * PR_SET_FPEXC (with PR_FP_EXC_SW_ENABLE in
1677 * the bits being set). <fenv.h> functions
1678 * saving and restoring the whole
1679 * floating-point environment need to do so
1680 * anyway to restore the prctl settings from
1681 * the saved environment.
1683 tsk->thread.spefscr_last = mfspr(SPRN_SPEFSCR);
1684 val = tsk->thread.fpexc_mode;
1691 val = __unpack_fe01(tsk->thread.fpexc_mode);
1692 return put_user(val, (unsigned int __user *) adr);
1695 int set_endian(struct task_struct *tsk, unsigned int val)
1697 struct pt_regs *regs = tsk->thread.regs;
1699 if ((val == PR_ENDIAN_LITTLE && !cpu_has_feature(CPU_FTR_REAL_LE)) ||
1700 (val == PR_ENDIAN_PPC_LITTLE && !cpu_has_feature(CPU_FTR_PPC_LE)))
1706 if (val == PR_ENDIAN_BIG)
1707 regs->msr &= ~MSR_LE;
1708 else if (val == PR_ENDIAN_LITTLE || val == PR_ENDIAN_PPC_LITTLE)
1709 regs->msr |= MSR_LE;
1716 int get_endian(struct task_struct *tsk, unsigned long adr)
1718 struct pt_regs *regs = tsk->thread.regs;
1721 if (!cpu_has_feature(CPU_FTR_PPC_LE) &&
1722 !cpu_has_feature(CPU_FTR_REAL_LE))
1728 if (regs->msr & MSR_LE) {
1729 if (cpu_has_feature(CPU_FTR_REAL_LE))
1730 val = PR_ENDIAN_LITTLE;
1732 val = PR_ENDIAN_PPC_LITTLE;
1734 val = PR_ENDIAN_BIG;
1736 return put_user(val, (unsigned int __user *)adr);
1739 int set_unalign_ctl(struct task_struct *tsk, unsigned int val)
1741 tsk->thread.align_ctl = val;
1745 int get_unalign_ctl(struct task_struct *tsk, unsigned long adr)
1747 return put_user(tsk->thread.align_ctl, (unsigned int __user *)adr);
1750 static inline int valid_irq_stack(unsigned long sp, struct task_struct *p,
1751 unsigned long nbytes)
1753 unsigned long stack_page;
1754 unsigned long cpu = task_cpu(p);
1757 * Avoid crashing if the stack has overflowed and corrupted
1758 * task_cpu(p), which is in the thread_info struct.
1760 if (cpu < NR_CPUS && cpu_possible(cpu)) {
1761 stack_page = (unsigned long) hardirq_ctx[cpu];
1762 if (sp >= stack_page + sizeof(struct thread_struct)
1763 && sp <= stack_page + THREAD_SIZE - nbytes)
1766 stack_page = (unsigned long) softirq_ctx[cpu];
1767 if (sp >= stack_page + sizeof(struct thread_struct)
1768 && sp <= stack_page + THREAD_SIZE - nbytes)
1774 int validate_sp(unsigned long sp, struct task_struct *p,
1775 unsigned long nbytes)
1777 unsigned long stack_page = (unsigned long)task_stack_page(p);
1779 if (sp >= stack_page + sizeof(struct thread_struct)
1780 && sp <= stack_page + THREAD_SIZE - nbytes)
1783 return valid_irq_stack(sp, p, nbytes);
1786 EXPORT_SYMBOL(validate_sp);
1788 unsigned long get_wchan(struct task_struct *p)
1790 unsigned long ip, sp;
1793 if (!p || p == current || p->state == TASK_RUNNING)
1797 if (!validate_sp(sp, p, STACK_FRAME_OVERHEAD))
1801 sp = *(unsigned long *)sp;
1802 if (!validate_sp(sp, p, STACK_FRAME_OVERHEAD))
1805 ip = ((unsigned long *)sp)[STACK_FRAME_LR_SAVE];
1806 if (!in_sched_functions(ip))
1809 } while (count++ < 16);
1813 static int kstack_depth_to_print = CONFIG_PRINT_STACK_DEPTH;
1815 void show_stack(struct task_struct *tsk, unsigned long *stack)
1817 unsigned long sp, ip, lr, newsp;
1820 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1821 int curr_frame = current->curr_ret_stack;
1822 extern void return_to_handler(void);
1823 unsigned long rth = (unsigned long)return_to_handler;
1826 sp = (unsigned long) stack;
1831 sp = current_stack_pointer();
1833 sp = tsk->thread.ksp;
1837 printk("Call Trace:\n");
1839 if (!validate_sp(sp, tsk, STACK_FRAME_OVERHEAD))
1842 stack = (unsigned long *) sp;
1844 ip = stack[STACK_FRAME_LR_SAVE];
1845 if (!firstframe || ip != lr) {
1846 printk("["REG"] ["REG"] %pS", sp, ip, (void *)ip);
1847 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1848 if ((ip == rth) && curr_frame >= 0) {
1850 (void *)current->ret_stack[curr_frame].ret);
1855 printk(" (unreliable)");
1861 * See if this is an exception frame.
1862 * We look for the "regshere" marker in the current frame.
1864 if (validate_sp(sp, tsk, STACK_INT_FRAME_SIZE)
1865 && stack[STACK_FRAME_MARKER] == STACK_FRAME_REGS_MARKER) {
1866 struct pt_regs *regs = (struct pt_regs *)
1867 (sp + STACK_FRAME_OVERHEAD);
1869 printk("--- interrupt: %lx at %pS\n LR = %pS\n",
1870 regs->trap, (void *)regs->nip, (void *)lr);
1875 } while (count++ < kstack_depth_to_print);
1879 /* Called with hard IRQs off */
1880 void notrace __ppc64_runlatch_on(void)
1882 struct thread_info *ti = current_thread_info();
1885 ctrl = mfspr(SPRN_CTRLF);
1886 ctrl |= CTRL_RUNLATCH;
1887 mtspr(SPRN_CTRLT, ctrl);
1889 ti->local_flags |= _TLF_RUNLATCH;
1892 /* Called with hard IRQs off */
1893 void notrace __ppc64_runlatch_off(void)
1895 struct thread_info *ti = current_thread_info();
1898 ti->local_flags &= ~_TLF_RUNLATCH;
1900 ctrl = mfspr(SPRN_CTRLF);
1901 ctrl &= ~CTRL_RUNLATCH;
1902 mtspr(SPRN_CTRLT, ctrl);
1904 #endif /* CONFIG_PPC64 */
1906 unsigned long arch_align_stack(unsigned long sp)
1908 if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
1909 sp -= get_random_int() & ~PAGE_MASK;
1913 static inline unsigned long brk_rnd(void)
1915 unsigned long rnd = 0;
1917 /* 8MB for 32bit, 1GB for 64bit */
1918 if (is_32bit_task())
1919 rnd = (get_random_long() % (1UL<<(23-PAGE_SHIFT)));
1921 rnd = (get_random_long() % (1UL<<(30-PAGE_SHIFT)));
1923 return rnd << PAGE_SHIFT;
1926 unsigned long arch_randomize_brk(struct mm_struct *mm)
1928 unsigned long base = mm->brk;
1931 #ifdef CONFIG_PPC_STD_MMU_64
1933 * If we are using 1TB segments and we are allowed to randomise
1934 * the heap, we can put it above 1TB so it is backed by a 1TB
1935 * segment. Otherwise the heap will be in the bottom 1TB
1936 * which always uses 256MB segments and this may result in a
1937 * performance penalty. We don't need to worry about radix. For
1938 * radix, mmu_highuser_ssize remains unchanged from 256MB.
1940 if (!is_32bit_task() && (mmu_highuser_ssize == MMU_SEGSIZE_1T))
1941 base = max_t(unsigned long, mm->brk, 1UL << SID_SHIFT_1T);
1944 ret = PAGE_ALIGN(base + brk_rnd());