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git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blob - arch/powerpc/kernel/process.c
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/init.h>
29 #include <linux/prctl.h>
30 #include <linux/init_task.h>
31 #include <linux/export.h>
32 #include <linux/kallsyms.h>
33 #include <linux/mqueue.h>
34 #include <linux/hardirq.h>
35 #include <linux/utsname.h>
36 #include <linux/ftrace.h>
37 #include <linux/kernel_stat.h>
38 #include <linux/personality.h>
39 #include <linux/random.h>
40 #include <linux/hw_breakpoint.h>
42 #include <asm/pgtable.h>
43 #include <asm/uaccess.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>
53 #include <asm/debug.h>
55 #include <asm/firmware.h>
57 #include <linux/kprobes.h>
58 #include <linux/kdebug.h>
60 extern unsigned long _get_SP(void);
63 struct task_struct
*last_task_used_math
= NULL
;
64 struct task_struct
*last_task_used_altivec
= NULL
;
65 struct task_struct
*last_task_used_vsx
= NULL
;
66 struct task_struct
*last_task_used_spe
= NULL
;
70 * Make sure the floating-point register state in the
71 * the thread_struct is up to date for task tsk.
73 void flush_fp_to_thread(struct task_struct
*tsk
)
75 if (tsk
->thread
.regs
) {
77 * We need to disable preemption here because if we didn't,
78 * another process could get scheduled after the regs->msr
79 * test but before we have finished saving the FP registers
80 * to the thread_struct. That process could take over the
81 * FPU, and then when we get scheduled again we would store
82 * bogus values for the remaining FP registers.
85 if (tsk
->thread
.regs
->msr
& MSR_FP
) {
88 * This should only ever be called for current or
89 * for a stopped child process. Since we save away
90 * the FP register state on context switch on SMP,
91 * there is something wrong if a stopped child appears
92 * to still have its FP state in the CPU registers.
94 BUG_ON(tsk
!= current
);
101 EXPORT_SYMBOL_GPL(flush_fp_to_thread
);
103 void enable_kernel_fp(void)
105 WARN_ON(preemptible());
108 if (current
->thread
.regs
&& (current
->thread
.regs
->msr
& MSR_FP
))
111 giveup_fpu(NULL
); /* just enables FP for kernel */
113 giveup_fpu(last_task_used_math
);
114 #endif /* CONFIG_SMP */
116 EXPORT_SYMBOL(enable_kernel_fp
);
118 #ifdef CONFIG_ALTIVEC
119 void enable_kernel_altivec(void)
121 WARN_ON(preemptible());
124 if (current
->thread
.regs
&& (current
->thread
.regs
->msr
& MSR_VEC
))
125 giveup_altivec(current
);
127 giveup_altivec_notask();
129 giveup_altivec(last_task_used_altivec
);
130 #endif /* CONFIG_SMP */
132 EXPORT_SYMBOL(enable_kernel_altivec
);
135 * Make sure the VMX/Altivec register state in the
136 * the thread_struct is up to date for task tsk.
138 void flush_altivec_to_thread(struct task_struct
*tsk
)
140 if (tsk
->thread
.regs
) {
142 if (tsk
->thread
.regs
->msr
& MSR_VEC
) {
144 BUG_ON(tsk
!= current
);
151 EXPORT_SYMBOL_GPL(flush_altivec_to_thread
);
152 #endif /* CONFIG_ALTIVEC */
156 /* not currently used, but some crazy RAID module might want to later */
157 void enable_kernel_vsx(void)
159 WARN_ON(preemptible());
162 if (current
->thread
.regs
&& (current
->thread
.regs
->msr
& MSR_VSX
))
165 giveup_vsx(NULL
); /* just enable vsx for kernel - force */
167 giveup_vsx(last_task_used_vsx
);
168 #endif /* CONFIG_SMP */
170 EXPORT_SYMBOL(enable_kernel_vsx
);
173 void giveup_vsx(struct task_struct
*tsk
)
180 void flush_vsx_to_thread(struct task_struct
*tsk
)
182 if (tsk
->thread
.regs
) {
184 if (tsk
->thread
.regs
->msr
& MSR_VSX
) {
186 BUG_ON(tsk
!= current
);
193 EXPORT_SYMBOL_GPL(flush_vsx_to_thread
);
194 #endif /* CONFIG_VSX */
198 void enable_kernel_spe(void)
200 WARN_ON(preemptible());
203 if (current
->thread
.regs
&& (current
->thread
.regs
->msr
& MSR_SPE
))
206 giveup_spe(NULL
); /* just enable SPE for kernel - force */
208 giveup_spe(last_task_used_spe
);
209 #endif /* __SMP __ */
211 EXPORT_SYMBOL(enable_kernel_spe
);
213 void flush_spe_to_thread(struct task_struct
*tsk
)
215 if (tsk
->thread
.regs
) {
217 if (tsk
->thread
.regs
->msr
& MSR_SPE
) {
219 BUG_ON(tsk
!= current
);
221 tsk
->thread
.spefscr
= mfspr(SPRN_SPEFSCR
);
227 #endif /* CONFIG_SPE */
231 * If we are doing lazy switching of CPU state (FP, altivec or SPE),
232 * and the current task has some state, discard it.
234 void discard_lazy_cpu_state(void)
237 if (last_task_used_math
== current
)
238 last_task_used_math
= NULL
;
239 #ifdef CONFIG_ALTIVEC
240 if (last_task_used_altivec
== current
)
241 last_task_used_altivec
= NULL
;
242 #endif /* CONFIG_ALTIVEC */
244 if (last_task_used_vsx
== current
)
245 last_task_used_vsx
= NULL
;
246 #endif /* CONFIG_VSX */
248 if (last_task_used_spe
== current
)
249 last_task_used_spe
= NULL
;
253 #endif /* CONFIG_SMP */
255 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
256 void do_send_trap(struct pt_regs
*regs
, unsigned long address
,
257 unsigned long error_code
, int signal_code
, int breakpt
)
261 current
->thread
.trap_nr
= signal_code
;
262 if (notify_die(DIE_DABR_MATCH
, "dabr_match", regs
, error_code
,
263 11, SIGSEGV
) == NOTIFY_STOP
)
266 /* Deliver the signal to userspace */
267 info
.si_signo
= SIGTRAP
;
268 info
.si_errno
= breakpt
; /* breakpoint or watchpoint id */
269 info
.si_code
= signal_code
;
270 info
.si_addr
= (void __user
*)address
;
271 force_sig_info(SIGTRAP
, &info
, current
);
273 #else /* !CONFIG_PPC_ADV_DEBUG_REGS */
274 void do_dabr(struct pt_regs
*regs
, unsigned long address
,
275 unsigned long error_code
)
279 current
->thread
.trap_nr
= TRAP_HWBKPT
;
280 if (notify_die(DIE_DABR_MATCH
, "dabr_match", regs
, error_code
,
281 11, SIGSEGV
) == NOTIFY_STOP
)
284 if (debugger_dabr_match(regs
))
290 /* Deliver the signal to userspace */
291 info
.si_signo
= SIGTRAP
;
293 info
.si_code
= TRAP_HWBKPT
;
294 info
.si_addr
= (void __user
*)address
;
295 force_sig_info(SIGTRAP
, &info
, current
);
297 #endif /* CONFIG_PPC_ADV_DEBUG_REGS */
299 static DEFINE_PER_CPU(unsigned long, current_dabr
);
301 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
303 * Set the debug registers back to their default "safe" values.
305 static void set_debug_reg_defaults(struct thread_struct
*thread
)
307 thread
->iac1
= thread
->iac2
= 0;
308 #if CONFIG_PPC_ADV_DEBUG_IACS > 2
309 thread
->iac3
= thread
->iac4
= 0;
311 thread
->dac1
= thread
->dac2
= 0;
312 #if CONFIG_PPC_ADV_DEBUG_DVCS > 0
313 thread
->dvc1
= thread
->dvc2
= 0;
318 * Force User/Supervisor bits to b11 (user-only MSR[PR]=1)
320 thread
->dbcr1
= DBCR1_IAC1US
| DBCR1_IAC2US
| \
321 DBCR1_IAC3US
| DBCR1_IAC4US
;
323 * Force Data Address Compare User/Supervisor bits to be User-only
324 * (0b11 MSR[PR]=1) and set all other bits in DBCR2 register to be 0.
326 thread
->dbcr2
= DBCR2_DAC1US
| DBCR2_DAC2US
;
332 static void prime_debug_regs(struct thread_struct
*thread
)
334 mtspr(SPRN_IAC1
, thread
->iac1
);
335 mtspr(SPRN_IAC2
, thread
->iac2
);
336 #if CONFIG_PPC_ADV_DEBUG_IACS > 2
337 mtspr(SPRN_IAC3
, thread
->iac3
);
338 mtspr(SPRN_IAC4
, thread
->iac4
);
340 mtspr(SPRN_DAC1
, thread
->dac1
);
341 mtspr(SPRN_DAC2
, thread
->dac2
);
342 #if CONFIG_PPC_ADV_DEBUG_DVCS > 0
343 mtspr(SPRN_DVC1
, thread
->dvc1
);
344 mtspr(SPRN_DVC2
, thread
->dvc2
);
346 mtspr(SPRN_DBCR0
, thread
->dbcr0
);
347 mtspr(SPRN_DBCR1
, thread
->dbcr1
);
349 mtspr(SPRN_DBCR2
, thread
->dbcr2
);
353 * Unless neither the old or new thread are making use of the
354 * debug registers, set the debug registers from the values
355 * stored in the new thread.
357 static void switch_booke_debug_regs(struct thread_struct
*new_thread
)
359 if ((current
->thread
.dbcr0
& DBCR0_IDM
)
360 || (new_thread
->dbcr0
& DBCR0_IDM
))
361 prime_debug_regs(new_thread
);
363 #else /* !CONFIG_PPC_ADV_DEBUG_REGS */
364 #ifndef CONFIG_HAVE_HW_BREAKPOINT
365 static void set_debug_reg_defaults(struct thread_struct
*thread
)
373 #endif /* !CONFIG_HAVE_HW_BREAKPOINT */
374 #endif /* CONFIG_PPC_ADV_DEBUG_REGS */
376 int set_dabr(unsigned long dabr
, unsigned long dabrx
)
378 __get_cpu_var(current_dabr
) = dabr
;
381 return ppc_md
.set_dabr(dabr
, dabrx
);
383 /* XXX should we have a CPU_FTR_HAS_DABR ? */
384 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
385 mtspr(SPRN_DAC1
, dabr
);
386 #ifdef CONFIG_PPC_47x
389 #elif defined(CONFIG_PPC_BOOK3S)
390 mtspr(SPRN_DABR
, dabr
);
391 mtspr(SPRN_DABRX
, dabrx
);
397 DEFINE_PER_CPU(struct cpu_usage
, cpu_usage_array
);
400 struct task_struct
*__switch_to(struct task_struct
*prev
,
401 struct task_struct
*new)
403 struct thread_struct
*new_thread
, *old_thread
;
405 struct task_struct
*last
;
406 #ifdef CONFIG_PPC_BOOK3S_64
407 struct ppc64_tlb_batch
*batch
;
411 /* avoid complexity of lazy save/restore of fpu
412 * by just saving it every time we switch out if
413 * this task used the fpu during the last quantum.
415 * If it tries to use the fpu again, it'll trap and
416 * reload its fp regs. So we don't have to do a restore
417 * every switch, just a save.
420 if (prev
->thread
.regs
&& (prev
->thread
.regs
->msr
& MSR_FP
))
422 #ifdef CONFIG_ALTIVEC
424 * If the previous thread used altivec in the last quantum
425 * (thus changing altivec regs) then save them.
426 * We used to check the VRSAVE register but not all apps
427 * set it, so we don't rely on it now (and in fact we need
428 * to save & restore VSCR even if VRSAVE == 0). -- paulus
430 * On SMP we always save/restore altivec regs just to avoid the
431 * complexity of changing processors.
434 if (prev
->thread
.regs
&& (prev
->thread
.regs
->msr
& MSR_VEC
))
435 giveup_altivec(prev
);
436 #endif /* CONFIG_ALTIVEC */
438 if (prev
->thread
.regs
&& (prev
->thread
.regs
->msr
& MSR_VSX
))
439 /* VMX and FPU registers are already save here */
441 #endif /* CONFIG_VSX */
444 * If the previous thread used spe in the last quantum
445 * (thus changing spe regs) then save them.
447 * On SMP we always save/restore spe regs just to avoid the
448 * complexity of changing processors.
450 if ((prev
->thread
.regs
&& (prev
->thread
.regs
->msr
& MSR_SPE
)))
452 #endif /* CONFIG_SPE */
454 #else /* CONFIG_SMP */
455 #ifdef CONFIG_ALTIVEC
456 /* Avoid the trap. On smp this this never happens since
457 * we don't set last_task_used_altivec -- Cort
459 if (new->thread
.regs
&& last_task_used_altivec
== new)
460 new->thread
.regs
->msr
|= MSR_VEC
;
461 #endif /* CONFIG_ALTIVEC */
463 if (new->thread
.regs
&& last_task_used_vsx
== new)
464 new->thread
.regs
->msr
|= MSR_VSX
;
465 #endif /* CONFIG_VSX */
467 /* Avoid the trap. On smp this this never happens since
468 * we don't set last_task_used_spe
470 if (new->thread
.regs
&& last_task_used_spe
== new)
471 new->thread
.regs
->msr
|= MSR_SPE
;
472 #endif /* CONFIG_SPE */
474 #endif /* CONFIG_SMP */
476 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
477 switch_booke_debug_regs(&new->thread
);
480 * For PPC_BOOK3S_64, we use the hw-breakpoint interfaces that would
483 #ifndef CONFIG_HAVE_HW_BREAKPOINT
484 if (unlikely(__get_cpu_var(current_dabr
) != new->thread
.dabr
))
485 set_dabr(new->thread
.dabr
, new->thread
.dabrx
);
486 #endif /* CONFIG_HAVE_HW_BREAKPOINT */
490 new_thread
= &new->thread
;
491 old_thread
= ¤t
->thread
;
495 * Collect processor utilization data per process
497 if (firmware_has_feature(FW_FEATURE_SPLPAR
)) {
498 struct cpu_usage
*cu
= &__get_cpu_var(cpu_usage_array
);
499 long unsigned start_tb
, current_tb
;
500 start_tb
= old_thread
->start_tb
;
501 cu
->current_tb
= current_tb
= mfspr(SPRN_PURR
);
502 old_thread
->accum_tb
+= (current_tb
- start_tb
);
503 new_thread
->start_tb
= current_tb
;
505 #endif /* CONFIG_PPC64 */
507 #ifdef CONFIG_PPC_BOOK3S_64
508 batch
= &__get_cpu_var(ppc64_tlb_batch
);
510 current_thread_info()->local_flags
|= _TLF_LAZY_MMU
;
512 __flush_tlb_pending(batch
);
515 #endif /* CONFIG_PPC_BOOK3S_64 */
517 local_irq_save(flags
);
520 * We can't take a PMU exception inside _switch() since there is a
521 * window where the kernel stack SLB and the kernel stack are out
522 * of sync. Hard disable here.
525 last
= _switch(old_thread
, new_thread
);
527 #ifdef CONFIG_PPC_BOOK3S_64
528 if (current_thread_info()->local_flags
& _TLF_LAZY_MMU
) {
529 current_thread_info()->local_flags
&= ~_TLF_LAZY_MMU
;
530 batch
= &__get_cpu_var(ppc64_tlb_batch
);
533 #endif /* CONFIG_PPC_BOOK3S_64 */
535 local_irq_restore(flags
);
540 static int instructions_to_print
= 16;
542 static void show_instructions(struct pt_regs
*regs
)
545 unsigned long pc
= regs
->nip
- (instructions_to_print
* 3 / 4 *
548 printk("Instruction dump:");
550 for (i
= 0; i
< instructions_to_print
; i
++) {
556 #if !defined(CONFIG_BOOKE)
557 /* If executing with the IMMU off, adjust pc rather
558 * than print XXXXXXXX.
560 if (!(regs
->msr
& MSR_IR
))
561 pc
= (unsigned long)phys_to_virt(pc
);
564 /* We use __get_user here *only* to avoid an OOPS on a
565 * bad address because the pc *should* only be a
568 if (!__kernel_text_address(pc
) ||
569 __get_user(instr
, (unsigned int __user
*)pc
)) {
570 printk(KERN_CONT
"XXXXXXXX ");
573 printk(KERN_CONT
"<%08x> ", instr
);
575 printk(KERN_CONT
"%08x ", instr
);
584 static struct regbit
{
588 #if defined(CONFIG_PPC64) && !defined(CONFIG_BOOKE)
617 static void printbits(unsigned long val
, struct regbit
*bits
)
619 const char *sep
= "";
622 for (; bits
->bit
; ++bits
)
623 if (val
& bits
->bit
) {
624 printk("%s%s", sep
, bits
->name
);
632 #define REGS_PER_LINE 4
633 #define LAST_VOLATILE 13
636 #define REGS_PER_LINE 8
637 #define LAST_VOLATILE 12
640 void show_regs(struct pt_regs
* regs
)
644 printk("NIP: "REG
" LR: "REG
" CTR: "REG
"\n",
645 regs
->nip
, regs
->link
, regs
->ctr
);
646 printk("REGS: %p TRAP: %04lx %s (%s)\n",
647 regs
, regs
->trap
, print_tainted(), init_utsname()->release
);
648 printk("MSR: "REG
" ", regs
->msr
);
649 printbits(regs
->msr
, msr_bits
);
650 printk(" CR: %08lx XER: %08lx\n", regs
->ccr
, regs
->xer
);
652 printk("SOFTE: %ld\n", regs
->softe
);
655 if ((regs
->trap
!= 0xc00) && cpu_has_feature(CPU_FTR_CFAR
))
656 printk("CFAR: "REG
"\n", regs
->orig_gpr3
);
657 if (trap
== 0x300 || trap
== 0x600)
658 #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE)
659 printk("DEAR: "REG
", ESR: "REG
"\n", regs
->dar
, regs
->dsisr
);
661 printk("DAR: "REG
", DSISR: %08lx\n", regs
->dar
, regs
->dsisr
);
663 printk("TASK = %p[%d] '%s' THREAD: %p",
664 current
, task_pid_nr(current
), current
->comm
, task_thread_info(current
));
667 printk(" CPU: %d", raw_smp_processor_id());
668 #endif /* CONFIG_SMP */
670 for (i
= 0; i
< 32; i
++) {
671 if ((i
% REGS_PER_LINE
) == 0)
672 printk("\nGPR%02d: ", i
);
673 printk(REG
" ", regs
->gpr
[i
]);
674 if (i
== LAST_VOLATILE
&& !FULL_REGS(regs
))
678 #ifdef CONFIG_KALLSYMS
680 * Lookup NIP late so we have the best change of getting the
681 * above info out without failing
683 printk("NIP ["REG
"] %pS\n", regs
->nip
, (void *)regs
->nip
);
684 printk("LR ["REG
"] %pS\n", regs
->link
, (void *)regs
->link
);
686 show_stack(current
, (unsigned long *) regs
->gpr
[1]);
687 if (!user_mode(regs
))
688 show_instructions(regs
);
691 void exit_thread(void)
693 discard_lazy_cpu_state();
696 void flush_thread(void)
698 discard_lazy_cpu_state();
700 #ifdef CONFIG_HAVE_HW_BREAKPOINT
701 flush_ptrace_hw_breakpoint(current
);
702 #else /* CONFIG_HAVE_HW_BREAKPOINT */
703 set_debug_reg_defaults(¤t
->thread
);
704 #endif /* CONFIG_HAVE_HW_BREAKPOINT */
708 release_thread(struct task_struct
*t
)
713 * this gets called so that we can store coprocessor state into memory and
714 * copy the current task into the new thread.
716 int arch_dup_task_struct(struct task_struct
*dst
, struct task_struct
*src
)
718 flush_fp_to_thread(src
);
719 flush_altivec_to_thread(src
);
720 flush_vsx_to_thread(src
);
721 flush_spe_to_thread(src
);
722 #ifdef CONFIG_HAVE_HW_BREAKPOINT
723 flush_ptrace_hw_breakpoint(src
);
724 #endif /* CONFIG_HAVE_HW_BREAKPOINT */
733 extern unsigned long dscr_default
; /* defined in arch/powerpc/kernel/sysfs.c */
735 int copy_thread(unsigned long clone_flags
, unsigned long usp
,
736 unsigned long arg
, struct task_struct
*p
,
737 struct pt_regs
*regs
)
739 struct pt_regs
*childregs
, *kregs
;
740 extern void ret_from_fork(void);
741 extern void ret_from_kernel_thread(void);
743 unsigned long sp
= (unsigned long)task_stack_page(p
) + THREAD_SIZE
;
746 sp
-= sizeof(struct pt_regs
);
747 childregs
= (struct pt_regs
*) sp
;
748 if (unlikely(p
->flags
& PF_KTHREAD
)) {
749 struct thread_info
*ti
= (void *)task_stack_page(p
);
750 memset(childregs
, 0, sizeof(struct pt_regs
));
751 childregs
->gpr
[1] = sp
+ sizeof(struct pt_regs
);
752 childregs
->gpr
[14] = usp
; /* function */
754 clear_tsk_thread_flag(p
, TIF_32BIT
);
755 childregs
->softe
= 1;
757 childregs
->gpr
[15] = arg
;
758 p
->thread
.regs
= NULL
; /* no user register state */
759 ti
->flags
|= _TIF_RESTOREALL
;
760 f
= ret_from_kernel_thread
;
762 CHECK_FULL_REGS(regs
);
765 childregs
->gpr
[1] = usp
;
766 p
->thread
.regs
= childregs
;
767 childregs
->gpr
[3] = 0; /* Result from fork() */
768 if (clone_flags
& CLONE_SETTLS
) {
770 if (!is_32bit_task())
771 childregs
->gpr
[13] = childregs
->gpr
[6];
774 childregs
->gpr
[2] = childregs
->gpr
[6];
779 sp
-= STACK_FRAME_OVERHEAD
;
782 * The way this works is that at some point in the future
783 * some task will call _switch to switch to the new task.
784 * That will pop off the stack frame created below and start
785 * the new task running at ret_from_fork. The new task will
786 * do some house keeping and then return from the fork or clone
787 * system call, using the stack frame created above.
789 sp
-= sizeof(struct pt_regs
);
790 kregs
= (struct pt_regs
*) sp
;
791 sp
-= STACK_FRAME_OVERHEAD
;
793 p
->thread
.ksp_limit
= (unsigned long)task_stack_page(p
) +
794 _ALIGN_UP(sizeof(struct thread_info
), 16);
796 #ifdef CONFIG_PPC_STD_MMU_64
797 if (mmu_has_feature(MMU_FTR_SLB
)) {
798 unsigned long sp_vsid
;
799 unsigned long llp
= mmu_psize_defs
[mmu_linear_psize
].sllp
;
801 if (mmu_has_feature(MMU_FTR_1T_SEGMENT
))
802 sp_vsid
= get_kernel_vsid(sp
, MMU_SEGSIZE_1T
)
803 << SLB_VSID_SHIFT_1T
;
805 sp_vsid
= get_kernel_vsid(sp
, MMU_SEGSIZE_256M
)
807 sp_vsid
|= SLB_VSID_KERNEL
| llp
;
808 p
->thread
.ksp_vsid
= sp_vsid
;
810 #endif /* CONFIG_PPC_STD_MMU_64 */
812 if (cpu_has_feature(CPU_FTR_DSCR
)) {
813 p
->thread
.dscr_inherit
= current
->thread
.dscr_inherit
;
814 p
->thread
.dscr
= current
->thread
.dscr
;
818 * The PPC64 ABI makes use of a TOC to contain function
819 * pointers. The function (ret_from_except) is actually a pointer
820 * to the TOC entry. The first entry is a pointer to the actual
824 kregs
->nip
= *((unsigned long *)f
);
826 kregs
->nip
= (unsigned long)f
;
832 * Set up a thread for executing a new program
834 void start_thread(struct pt_regs
*regs
, unsigned long start
, unsigned long sp
)
837 unsigned long load_addr
= regs
->gpr
[2]; /* saved by ELF_PLAT_INIT */
841 * If we exec out of a kernel thread then thread.regs will not be
844 if (!current
->thread
.regs
) {
845 struct pt_regs
*regs
= task_stack_page(current
) + THREAD_SIZE
;
846 current
->thread
.regs
= regs
- 1;
849 memset(regs
->gpr
, 0, sizeof(regs
->gpr
));
857 * We have just cleared all the nonvolatile GPRs, so make
858 * FULL_REGS(regs) return true. This is necessary to allow
859 * ptrace to examine the thread immediately after exec.
866 regs
->msr
= MSR_USER
;
868 if (!is_32bit_task()) {
869 unsigned long entry
, toc
;
871 /* start is a relocated pointer to the function descriptor for
872 * the elf _start routine. The first entry in the function
873 * descriptor is the entry address of _start and the second
874 * entry is the TOC value we need to use.
876 __get_user(entry
, (unsigned long __user
*)start
);
877 __get_user(toc
, (unsigned long __user
*)start
+1);
879 /* Check whether the e_entry function descriptor entries
880 * need to be relocated before we can use them.
882 if (load_addr
!= 0) {
888 regs
->msr
= MSR_USER64
;
892 regs
->msr
= MSR_USER32
;
896 discard_lazy_cpu_state();
898 current
->thread
.used_vsr
= 0;
900 memset(current
->thread
.fpr
, 0, sizeof(current
->thread
.fpr
));
901 current
->thread
.fpscr
.val
= 0;
902 #ifdef CONFIG_ALTIVEC
903 memset(current
->thread
.vr
, 0, sizeof(current
->thread
.vr
));
904 memset(¤t
->thread
.vscr
, 0, sizeof(current
->thread
.vscr
));
905 current
->thread
.vscr
.u
[3] = 0x00010000; /* Java mode disabled */
906 current
->thread
.vrsave
= 0;
907 current
->thread
.used_vr
= 0;
908 #endif /* CONFIG_ALTIVEC */
910 memset(current
->thread
.evr
, 0, sizeof(current
->thread
.evr
));
911 current
->thread
.acc
= 0;
912 current
->thread
.spefscr
= 0;
913 current
->thread
.used_spe
= 0;
914 #endif /* CONFIG_SPE */
917 #define PR_FP_ALL_EXCEPT (PR_FP_EXC_DIV | PR_FP_EXC_OVF | PR_FP_EXC_UND \
918 | PR_FP_EXC_RES | PR_FP_EXC_INV)
920 int set_fpexc_mode(struct task_struct
*tsk
, unsigned int val
)
922 struct pt_regs
*regs
= tsk
->thread
.regs
;
924 /* This is a bit hairy. If we are an SPE enabled processor
925 * (have embedded fp) we store the IEEE exception enable flags in
926 * fpexc_mode. fpexc_mode is also used for setting FP exception
927 * mode (asyn, precise, disabled) for 'Classic' FP. */
928 if (val
& PR_FP_EXC_SW_ENABLE
) {
930 if (cpu_has_feature(CPU_FTR_SPE
)) {
931 tsk
->thread
.fpexc_mode
= val
&
932 (PR_FP_EXC_SW_ENABLE
| PR_FP_ALL_EXCEPT
);
942 /* on a CONFIG_SPE this does not hurt us. The bits that
943 * __pack_fe01 use do not overlap with bits used for
944 * PR_FP_EXC_SW_ENABLE. Additionally, the MSR[FE0,FE1] bits
945 * on CONFIG_SPE implementations are reserved so writing to
946 * them does not change anything */
947 if (val
> PR_FP_EXC_PRECISE
)
949 tsk
->thread
.fpexc_mode
= __pack_fe01(val
);
950 if (regs
!= NULL
&& (regs
->msr
& MSR_FP
) != 0)
951 regs
->msr
= (regs
->msr
& ~(MSR_FE0
|MSR_FE1
))
952 | tsk
->thread
.fpexc_mode
;
956 int get_fpexc_mode(struct task_struct
*tsk
, unsigned long adr
)
960 if (tsk
->thread
.fpexc_mode
& PR_FP_EXC_SW_ENABLE
)
962 if (cpu_has_feature(CPU_FTR_SPE
))
963 val
= tsk
->thread
.fpexc_mode
;
970 val
= __unpack_fe01(tsk
->thread
.fpexc_mode
);
971 return put_user(val
, (unsigned int __user
*) adr
);
974 int set_endian(struct task_struct
*tsk
, unsigned int val
)
976 struct pt_regs
*regs
= tsk
->thread
.regs
;
978 if ((val
== PR_ENDIAN_LITTLE
&& !cpu_has_feature(CPU_FTR_REAL_LE
)) ||
979 (val
== PR_ENDIAN_PPC_LITTLE
&& !cpu_has_feature(CPU_FTR_PPC_LE
)))
985 if (val
== PR_ENDIAN_BIG
)
986 regs
->msr
&= ~MSR_LE
;
987 else if (val
== PR_ENDIAN_LITTLE
|| val
== PR_ENDIAN_PPC_LITTLE
)
995 int get_endian(struct task_struct
*tsk
, unsigned long adr
)
997 struct pt_regs
*regs
= tsk
->thread
.regs
;
1000 if (!cpu_has_feature(CPU_FTR_PPC_LE
) &&
1001 !cpu_has_feature(CPU_FTR_REAL_LE
))
1007 if (regs
->msr
& MSR_LE
) {
1008 if (cpu_has_feature(CPU_FTR_REAL_LE
))
1009 val
= PR_ENDIAN_LITTLE
;
1011 val
= PR_ENDIAN_PPC_LITTLE
;
1013 val
= PR_ENDIAN_BIG
;
1015 return put_user(val
, (unsigned int __user
*)adr
);
1018 int set_unalign_ctl(struct task_struct
*tsk
, unsigned int val
)
1020 tsk
->thread
.align_ctl
= val
;
1024 int get_unalign_ctl(struct task_struct
*tsk
, unsigned long adr
)
1026 return put_user(tsk
->thread
.align_ctl
, (unsigned int __user
*)adr
);
1029 int sys_clone(unsigned long clone_flags
, unsigned long usp
,
1030 int __user
*parent_tidp
, void __user
*child_threadptr
,
1031 int __user
*child_tidp
, int p6
,
1032 struct pt_regs
*regs
)
1034 return do_fork(clone_flags
, usp
, regs
, 0, parent_tidp
, child_tidp
);
1037 int sys_fork(unsigned long p1
, unsigned long p2
, unsigned long p3
,
1038 unsigned long p4
, unsigned long p5
, unsigned long p6
,
1039 struct pt_regs
*regs
)
1041 return do_fork(SIGCHLD
, 0, regs
, 0, NULL
, NULL
);
1044 int sys_vfork(unsigned long p1
, unsigned long p2
, unsigned long p3
,
1045 unsigned long p4
, unsigned long p5
, unsigned long p6
,
1046 struct pt_regs
*regs
)
1048 return do_fork(CLONE_VFORK
| CLONE_VM
| SIGCHLD
, 0,
1049 regs
, 0, NULL
, NULL
);
1052 static inline int valid_irq_stack(unsigned long sp
, struct task_struct
*p
,
1053 unsigned long nbytes
)
1055 unsigned long stack_page
;
1056 unsigned long cpu
= task_cpu(p
);
1059 * Avoid crashing if the stack has overflowed and corrupted
1060 * task_cpu(p), which is in the thread_info struct.
1062 if (cpu
< NR_CPUS
&& cpu_possible(cpu
)) {
1063 stack_page
= (unsigned long) hardirq_ctx
[cpu
];
1064 if (sp
>= stack_page
+ sizeof(struct thread_struct
)
1065 && sp
<= stack_page
+ THREAD_SIZE
- nbytes
)
1068 stack_page
= (unsigned long) softirq_ctx
[cpu
];
1069 if (sp
>= stack_page
+ sizeof(struct thread_struct
)
1070 && sp
<= stack_page
+ THREAD_SIZE
- nbytes
)
1076 int validate_sp(unsigned long sp
, struct task_struct
*p
,
1077 unsigned long nbytes
)
1079 unsigned long stack_page
= (unsigned long)task_stack_page(p
);
1081 if (sp
>= stack_page
+ sizeof(struct thread_struct
)
1082 && sp
<= stack_page
+ THREAD_SIZE
- nbytes
)
1085 return valid_irq_stack(sp
, p
, nbytes
);
1088 EXPORT_SYMBOL(validate_sp
);
1090 unsigned long get_wchan(struct task_struct
*p
)
1092 unsigned long ip
, sp
;
1095 if (!p
|| p
== current
|| p
->state
== TASK_RUNNING
)
1099 if (!validate_sp(sp
, p
, STACK_FRAME_OVERHEAD
))
1103 sp
= *(unsigned long *)sp
;
1104 if (!validate_sp(sp
, p
, STACK_FRAME_OVERHEAD
))
1107 ip
= ((unsigned long *)sp
)[STACK_FRAME_LR_SAVE
];
1108 if (!in_sched_functions(ip
))
1111 } while (count
++ < 16);
1115 static int kstack_depth_to_print
= CONFIG_PRINT_STACK_DEPTH
;
1117 void show_stack(struct task_struct
*tsk
, unsigned long *stack
)
1119 unsigned long sp
, ip
, lr
, newsp
;
1122 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1123 int curr_frame
= current
->curr_ret_stack
;
1124 extern void return_to_handler(void);
1125 unsigned long rth
= (unsigned long)return_to_handler
;
1126 unsigned long mrth
= -1;
1128 extern void mod_return_to_handler(void);
1129 rth
= *(unsigned long *)rth
;
1130 mrth
= (unsigned long)mod_return_to_handler
;
1131 mrth
= *(unsigned long *)mrth
;
1135 sp
= (unsigned long) stack
;
1140 asm("mr %0,1" : "=r" (sp
));
1142 sp
= tsk
->thread
.ksp
;
1146 printk("Call Trace:\n");
1148 if (!validate_sp(sp
, tsk
, STACK_FRAME_OVERHEAD
))
1151 stack
= (unsigned long *) sp
;
1153 ip
= stack
[STACK_FRAME_LR_SAVE
];
1154 if (!firstframe
|| ip
!= lr
) {
1155 printk("["REG
"] ["REG
"] %pS", sp
, ip
, (void *)ip
);
1156 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1157 if ((ip
== rth
|| ip
== mrth
) && curr_frame
>= 0) {
1159 (void *)current
->ret_stack
[curr_frame
].ret
);
1164 printk(" (unreliable)");
1170 * See if this is an exception frame.
1171 * We look for the "regshere" marker in the current frame.
1173 if (validate_sp(sp
, tsk
, STACK_INT_FRAME_SIZE
)
1174 && stack
[STACK_FRAME_MARKER
] == STACK_FRAME_REGS_MARKER
) {
1175 struct pt_regs
*regs
= (struct pt_regs
*)
1176 (sp
+ STACK_FRAME_OVERHEAD
);
1178 printk("--- Exception: %lx at %pS\n LR = %pS\n",
1179 regs
->trap
, (void *)regs
->nip
, (void *)lr
);
1184 } while (count
++ < kstack_depth_to_print
);
1187 void dump_stack(void)
1189 show_stack(current
, NULL
);
1191 EXPORT_SYMBOL(dump_stack
);
1194 /* Called with hard IRQs off */
1195 void __ppc64_runlatch_on(void)
1197 struct thread_info
*ti
= current_thread_info();
1200 ctrl
= mfspr(SPRN_CTRLF
);
1201 ctrl
|= CTRL_RUNLATCH
;
1202 mtspr(SPRN_CTRLT
, ctrl
);
1204 ti
->local_flags
|= _TLF_RUNLATCH
;
1207 /* Called with hard IRQs off */
1208 void __ppc64_runlatch_off(void)
1210 struct thread_info
*ti
= current_thread_info();
1213 ti
->local_flags
&= ~_TLF_RUNLATCH
;
1215 ctrl
= mfspr(SPRN_CTRLF
);
1216 ctrl
&= ~CTRL_RUNLATCH
;
1217 mtspr(SPRN_CTRLT
, ctrl
);
1219 #endif /* CONFIG_PPC64 */
1221 unsigned long arch_align_stack(unsigned long sp
)
1223 if (!(current
->personality
& ADDR_NO_RANDOMIZE
) && randomize_va_space
)
1224 sp
-= get_random_int() & ~PAGE_MASK
;
1228 static inline unsigned long brk_rnd(void)
1230 unsigned long rnd
= 0;
1232 /* 8MB for 32bit, 1GB for 64bit */
1233 if (is_32bit_task())
1234 rnd
= (long)(get_random_int() % (1<<(23-PAGE_SHIFT
)));
1236 rnd
= (long)(get_random_int() % (1<<(30-PAGE_SHIFT
)));
1238 return rnd
<< PAGE_SHIFT
;
1241 unsigned long arch_randomize_brk(struct mm_struct
*mm
)
1243 unsigned long base
= mm
->brk
;
1246 #ifdef CONFIG_PPC_STD_MMU_64
1248 * If we are using 1TB segments and we are allowed to randomise
1249 * the heap, we can put it above 1TB so it is backed by a 1TB
1250 * segment. Otherwise the heap will be in the bottom 1TB
1251 * which always uses 256MB segments and this may result in a
1252 * performance penalty.
1254 if (!is_32bit_task() && (mmu_highuser_ssize
== MMU_SEGSIZE_1T
))
1255 base
= max_t(unsigned long, mm
->brk
, 1UL << SID_SHIFT_1T
);
1258 ret
= PAGE_ALIGN(base
+ brk_rnd());
1266 unsigned long randomize_et_dyn(unsigned long base
)
1268 unsigned long ret
= PAGE_ALIGN(base
+ brk_rnd());