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/module.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>
44 #include <asm/system.h>
46 #include <asm/processor.h>
49 #include <asm/machdep.h>
51 #include <asm/syscalls.h>
53 #include <asm/firmware.h>
55 #include <linux/kprobes.h>
56 #include <linux/kdebug.h>
58 extern unsigned long _get_SP(void);
61 struct task_struct
*last_task_used_math
= NULL
;
62 struct task_struct
*last_task_used_altivec
= NULL
;
63 struct task_struct
*last_task_used_vsx
= NULL
;
64 struct task_struct
*last_task_used_spe
= NULL
;
68 * Make sure the floating-point register state in the
69 * the thread_struct is up to date for task tsk.
71 void flush_fp_to_thread(struct task_struct
*tsk
)
73 if (tsk
->thread
.regs
) {
75 * We need to disable preemption here because if we didn't,
76 * another process could get scheduled after the regs->msr
77 * test but before we have finished saving the FP registers
78 * to the thread_struct. That process could take over the
79 * FPU, and then when we get scheduled again we would store
80 * bogus values for the remaining FP registers.
83 if (tsk
->thread
.regs
->msr
& MSR_FP
) {
86 * This should only ever be called for current or
87 * for a stopped child process. Since we save away
88 * the FP register state on context switch on SMP,
89 * there is something wrong if a stopped child appears
90 * to still have its FP state in the CPU registers.
92 BUG_ON(tsk
!= current
);
100 void enable_kernel_fp(void)
102 WARN_ON(preemptible());
105 if (current
->thread
.regs
&& (current
->thread
.regs
->msr
& MSR_FP
))
108 giveup_fpu(NULL
); /* just enables FP for kernel */
110 giveup_fpu(last_task_used_math
);
111 #endif /* CONFIG_SMP */
113 EXPORT_SYMBOL(enable_kernel_fp
);
115 #ifdef CONFIG_ALTIVEC
116 void enable_kernel_altivec(void)
118 WARN_ON(preemptible());
121 if (current
->thread
.regs
&& (current
->thread
.regs
->msr
& MSR_VEC
))
122 giveup_altivec(current
);
124 giveup_altivec(NULL
); /* just enable AltiVec for kernel - force */
126 giveup_altivec(last_task_used_altivec
);
127 #endif /* CONFIG_SMP */
129 EXPORT_SYMBOL(enable_kernel_altivec
);
132 * Make sure the VMX/Altivec register state in the
133 * the thread_struct is up to date for task tsk.
135 void flush_altivec_to_thread(struct task_struct
*tsk
)
137 if (tsk
->thread
.regs
) {
139 if (tsk
->thread
.regs
->msr
& MSR_VEC
) {
141 BUG_ON(tsk
!= current
);
148 #endif /* CONFIG_ALTIVEC */
152 /* not currently used, but some crazy RAID module might want to later */
153 void enable_kernel_vsx(void)
155 WARN_ON(preemptible());
158 if (current
->thread
.regs
&& (current
->thread
.regs
->msr
& MSR_VSX
))
161 giveup_vsx(NULL
); /* just enable vsx for kernel - force */
163 giveup_vsx(last_task_used_vsx
);
164 #endif /* CONFIG_SMP */
166 EXPORT_SYMBOL(enable_kernel_vsx
);
169 void giveup_vsx(struct task_struct
*tsk
)
176 void flush_vsx_to_thread(struct task_struct
*tsk
)
178 if (tsk
->thread
.regs
) {
180 if (tsk
->thread
.regs
->msr
& MSR_VSX
) {
182 BUG_ON(tsk
!= current
);
189 #endif /* CONFIG_VSX */
193 void enable_kernel_spe(void)
195 WARN_ON(preemptible());
198 if (current
->thread
.regs
&& (current
->thread
.regs
->msr
& MSR_SPE
))
201 giveup_spe(NULL
); /* just enable SPE for kernel - force */
203 giveup_spe(last_task_used_spe
);
204 #endif /* __SMP __ */
206 EXPORT_SYMBOL(enable_kernel_spe
);
208 void flush_spe_to_thread(struct task_struct
*tsk
)
210 if (tsk
->thread
.regs
) {
212 if (tsk
->thread
.regs
->msr
& MSR_SPE
) {
214 BUG_ON(tsk
!= current
);
221 #endif /* CONFIG_SPE */
225 * If we are doing lazy switching of CPU state (FP, altivec or SPE),
226 * and the current task has some state, discard it.
228 void discard_lazy_cpu_state(void)
231 if (last_task_used_math
== current
)
232 last_task_used_math
= NULL
;
233 #ifdef CONFIG_ALTIVEC
234 if (last_task_used_altivec
== current
)
235 last_task_used_altivec
= NULL
;
236 #endif /* CONFIG_ALTIVEC */
238 if (last_task_used_vsx
== current
)
239 last_task_used_vsx
= NULL
;
240 #endif /* CONFIG_VSX */
242 if (last_task_used_spe
== current
)
243 last_task_used_spe
= NULL
;
247 #endif /* CONFIG_SMP */
249 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
250 void do_send_trap(struct pt_regs
*regs
, unsigned long address
,
251 unsigned long error_code
, int signal_code
, int breakpt
)
255 if (notify_die(DIE_DABR_MATCH
, "dabr_match", regs
, error_code
,
256 11, SIGSEGV
) == NOTIFY_STOP
)
259 /* Deliver the signal to userspace */
260 info
.si_signo
= SIGTRAP
;
261 info
.si_errno
= breakpt
; /* breakpoint or watchpoint id */
262 info
.si_code
= signal_code
;
263 info
.si_addr
= (void __user
*)address
;
264 force_sig_info(SIGTRAP
, &info
, current
);
266 #else /* !CONFIG_PPC_ADV_DEBUG_REGS */
267 void do_dabr(struct pt_regs
*regs
, unsigned long address
,
268 unsigned long error_code
)
272 if (notify_die(DIE_DABR_MATCH
, "dabr_match", regs
, error_code
,
273 11, SIGSEGV
) == NOTIFY_STOP
)
276 if (debugger_dabr_match(regs
))
282 /* Deliver the signal to userspace */
283 info
.si_signo
= SIGTRAP
;
285 info
.si_code
= TRAP_HWBKPT
;
286 info
.si_addr
= (void __user
*)address
;
287 force_sig_info(SIGTRAP
, &info
, current
);
289 #endif /* CONFIG_PPC_ADV_DEBUG_REGS */
291 static DEFINE_PER_CPU(unsigned long, current_dabr
);
293 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
295 * Set the debug registers back to their default "safe" values.
297 static void set_debug_reg_defaults(struct thread_struct
*thread
)
299 thread
->iac1
= thread
->iac2
= 0;
300 #if CONFIG_PPC_ADV_DEBUG_IACS > 2
301 thread
->iac3
= thread
->iac4
= 0;
303 thread
->dac1
= thread
->dac2
= 0;
304 #if CONFIG_PPC_ADV_DEBUG_DVCS > 0
305 thread
->dvc1
= thread
->dvc2
= 0;
310 * Force User/Supervisor bits to b11 (user-only MSR[PR]=1)
312 thread
->dbcr1
= DBCR1_IAC1US
| DBCR1_IAC2US
| \
313 DBCR1_IAC3US
| DBCR1_IAC4US
;
315 * Force Data Address Compare User/Supervisor bits to be User-only
316 * (0b11 MSR[PR]=1) and set all other bits in DBCR2 register to be 0.
318 thread
->dbcr2
= DBCR2_DAC1US
| DBCR2_DAC2US
;
324 static void prime_debug_regs(struct thread_struct
*thread
)
326 mtspr(SPRN_IAC1
, thread
->iac1
);
327 mtspr(SPRN_IAC2
, thread
->iac2
);
328 #if CONFIG_PPC_ADV_DEBUG_IACS > 2
329 mtspr(SPRN_IAC3
, thread
->iac3
);
330 mtspr(SPRN_IAC4
, thread
->iac4
);
332 mtspr(SPRN_DAC1
, thread
->dac1
);
333 mtspr(SPRN_DAC2
, thread
->dac2
);
334 #if CONFIG_PPC_ADV_DEBUG_DVCS > 0
335 mtspr(SPRN_DVC1
, thread
->dvc1
);
336 mtspr(SPRN_DVC2
, thread
->dvc2
);
338 mtspr(SPRN_DBCR0
, thread
->dbcr0
);
339 mtspr(SPRN_DBCR1
, thread
->dbcr1
);
341 mtspr(SPRN_DBCR2
, thread
->dbcr2
);
345 * Unless neither the old or new thread are making use of the
346 * debug registers, set the debug registers from the values
347 * stored in the new thread.
349 static void switch_booke_debug_regs(struct thread_struct
*new_thread
)
351 if ((current
->thread
.dbcr0
& DBCR0_IDM
)
352 || (new_thread
->dbcr0
& DBCR0_IDM
))
353 prime_debug_regs(new_thread
);
355 #else /* !CONFIG_PPC_ADV_DEBUG_REGS */
356 static void set_debug_reg_defaults(struct thread_struct
*thread
)
363 #endif /* CONFIG_PPC_ADV_DEBUG_REGS */
365 int set_dabr(unsigned long dabr
)
367 __get_cpu_var(current_dabr
) = dabr
;
370 return ppc_md
.set_dabr(dabr
);
372 /* XXX should we have a CPU_FTR_HAS_DABR ? */
373 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
374 mtspr(SPRN_DAC1
, dabr
);
375 #ifdef CONFIG_PPC_47x
378 #elif defined(CONFIG_PPC_BOOK3S)
379 mtspr(SPRN_DABR
, dabr
);
387 DEFINE_PER_CPU(struct cpu_usage
, cpu_usage_array
);
390 struct task_struct
*__switch_to(struct task_struct
*prev
,
391 struct task_struct
*new)
393 struct thread_struct
*new_thread
, *old_thread
;
395 struct task_struct
*last
;
398 /* avoid complexity of lazy save/restore of fpu
399 * by just saving it every time we switch out if
400 * this task used the fpu during the last quantum.
402 * If it tries to use the fpu again, it'll trap and
403 * reload its fp regs. So we don't have to do a restore
404 * every switch, just a save.
407 if (prev
->thread
.regs
&& (prev
->thread
.regs
->msr
& MSR_FP
))
409 #ifdef CONFIG_ALTIVEC
411 * If the previous thread used altivec in the last quantum
412 * (thus changing altivec regs) then save them.
413 * We used to check the VRSAVE register but not all apps
414 * set it, so we don't rely on it now (and in fact we need
415 * to save & restore VSCR even if VRSAVE == 0). -- paulus
417 * On SMP we always save/restore altivec regs just to avoid the
418 * complexity of changing processors.
421 if (prev
->thread
.regs
&& (prev
->thread
.regs
->msr
& MSR_VEC
))
422 giveup_altivec(prev
);
423 #endif /* CONFIG_ALTIVEC */
425 if (prev
->thread
.regs
&& (prev
->thread
.regs
->msr
& MSR_VSX
))
426 /* VMX and FPU registers are already save here */
428 #endif /* CONFIG_VSX */
431 * If the previous thread used spe in the last quantum
432 * (thus changing spe regs) then save them.
434 * On SMP we always save/restore spe regs just to avoid the
435 * complexity of changing processors.
437 if ((prev
->thread
.regs
&& (prev
->thread
.regs
->msr
& MSR_SPE
)))
439 #endif /* CONFIG_SPE */
441 #else /* CONFIG_SMP */
442 #ifdef CONFIG_ALTIVEC
443 /* Avoid the trap. On smp this this never happens since
444 * we don't set last_task_used_altivec -- Cort
446 if (new->thread
.regs
&& last_task_used_altivec
== new)
447 new->thread
.regs
->msr
|= MSR_VEC
;
448 #endif /* CONFIG_ALTIVEC */
450 if (new->thread
.regs
&& last_task_used_vsx
== new)
451 new->thread
.regs
->msr
|= MSR_VSX
;
452 #endif /* CONFIG_VSX */
454 /* Avoid the trap. On smp this this never happens since
455 * we don't set last_task_used_spe
457 if (new->thread
.regs
&& last_task_used_spe
== new)
458 new->thread
.regs
->msr
|= MSR_SPE
;
459 #endif /* CONFIG_SPE */
461 #endif /* CONFIG_SMP */
463 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
464 switch_booke_debug_regs(&new->thread
);
467 * For PPC_BOOK3S_64, we use the hw-breakpoint interfaces that would
470 #ifndef CONFIG_HAVE_HW_BREAKPOINT
471 if (unlikely(__get_cpu_var(current_dabr
) != new->thread
.dabr
))
472 set_dabr(new->thread
.dabr
);
473 #endif /* CONFIG_HAVE_HW_BREAKPOINT */
477 new_thread
= &new->thread
;
478 old_thread
= ¤t
->thread
;
480 #if defined(CONFIG_PPC_BOOK3E_64)
481 /* XXX Current Book3E code doesn't deal with kernel side DBCR0,
482 * we always hold the user values, so we set it now.
484 * However, we ensure the kernel MSR:DE is appropriately cleared too
485 * to avoid spurrious single step exceptions in the kernel.
487 * This will have to change to merge with the ppc32 code at some point,
488 * but I don't like much what ppc32 is doing today so there's some
489 * thinking needed there
491 if ((new_thread
->dbcr0
| old_thread
->dbcr0
) & DBCR0_IDM
) {
494 mtmsr(mfmsr() & ~MSR_DE
);
496 dbcr0
= mfspr(SPRN_DBCR0
);
497 dbcr0
= (dbcr0
& DBCR0_EDM
) | new_thread
->dbcr0
;
498 mtspr(SPRN_DBCR0
, dbcr0
);
500 #endif /* CONFIG_PPC64_BOOK3E */
504 * Collect processor utilization data per process
506 if (firmware_has_feature(FW_FEATURE_SPLPAR
)) {
507 struct cpu_usage
*cu
= &__get_cpu_var(cpu_usage_array
);
508 long unsigned start_tb
, current_tb
;
509 start_tb
= old_thread
->start_tb
;
510 cu
->current_tb
= current_tb
= mfspr(SPRN_PURR
);
511 old_thread
->accum_tb
+= (current_tb
- start_tb
);
512 new_thread
->start_tb
= current_tb
;
516 local_irq_save(flags
);
518 account_system_vtime(current
);
519 account_process_vtime(current
);
520 calculate_steal_time();
523 * We can't take a PMU exception inside _switch() since there is a
524 * window where the kernel stack SLB and the kernel stack are out
525 * of sync. Hard disable here.
528 last
= _switch(old_thread
, new_thread
);
530 local_irq_restore(flags
);
535 static int instructions_to_print
= 16;
537 static void show_instructions(struct pt_regs
*regs
)
540 unsigned long pc
= regs
->nip
- (instructions_to_print
* 3 / 4 *
543 printk("Instruction dump:");
545 for (i
= 0; i
< instructions_to_print
; i
++) {
551 #if !defined(CONFIG_BOOKE)
552 /* If executing with the IMMU off, adjust pc rather
553 * than print XXXXXXXX.
555 if (!(regs
->msr
& MSR_IR
))
556 pc
= (unsigned long)phys_to_virt(pc
);
559 /* We use __get_user here *only* to avoid an OOPS on a
560 * bad address because the pc *should* only be a
563 if (!__kernel_text_address(pc
) ||
564 __get_user(instr
, (unsigned int __user
*)pc
)) {
568 printk("<%08x> ", instr
);
570 printk("%08x ", instr
);
579 static struct regbit
{
596 static void printbits(unsigned long val
, struct regbit
*bits
)
598 const char *sep
= "";
601 for (; bits
->bit
; ++bits
)
602 if (val
& bits
->bit
) {
603 printk("%s%s", sep
, bits
->name
);
611 #define REGS_PER_LINE 4
612 #define LAST_VOLATILE 13
615 #define REGS_PER_LINE 8
616 #define LAST_VOLATILE 12
619 void show_regs(struct pt_regs
* regs
)
623 printk("NIP: "REG
" LR: "REG
" CTR: "REG
"\n",
624 regs
->nip
, regs
->link
, regs
->ctr
);
625 printk("REGS: %p TRAP: %04lx %s (%s)\n",
626 regs
, regs
->trap
, print_tainted(), init_utsname()->release
);
627 printk("MSR: "REG
" ", regs
->msr
);
628 printbits(regs
->msr
, msr_bits
);
629 printk(" CR: %08lx XER: %08lx\n", regs
->ccr
, regs
->xer
);
631 if (trap
== 0x300 || trap
== 0x600)
632 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
633 printk("DEAR: "REG
", ESR: "REG
"\n", regs
->dar
, regs
->dsisr
);
635 printk("DAR: "REG
", DSISR: "REG
"\n", regs
->dar
, regs
->dsisr
);
637 printk("TASK = %p[%d] '%s' THREAD: %p",
638 current
, task_pid_nr(current
), current
->comm
, task_thread_info(current
));
641 printk(" CPU: %d", raw_smp_processor_id());
642 #endif /* CONFIG_SMP */
644 for (i
= 0; i
< 32; i
++) {
645 if ((i
% REGS_PER_LINE
) == 0)
646 printk("\nGPR%02d: ", i
);
647 printk(REG
" ", regs
->gpr
[i
]);
648 if (i
== LAST_VOLATILE
&& !FULL_REGS(regs
))
652 #ifdef CONFIG_KALLSYMS
654 * Lookup NIP late so we have the best change of getting the
655 * above info out without failing
657 printk("NIP ["REG
"] %pS\n", regs
->nip
, (void *)regs
->nip
);
658 printk("LR ["REG
"] %pS\n", regs
->link
, (void *)regs
->link
);
660 show_stack(current
, (unsigned long *) regs
->gpr
[1]);
661 if (!user_mode(regs
))
662 show_instructions(regs
);
665 void exit_thread(void)
667 discard_lazy_cpu_state();
670 void flush_thread(void)
672 discard_lazy_cpu_state();
674 #ifdef CONFIG_HAVE_HW_BREAKPOINTS
675 flush_ptrace_hw_breakpoint(current
);
676 #else /* CONFIG_HAVE_HW_BREAKPOINTS */
677 set_debug_reg_defaults(¤t
->thread
);
678 #endif /* CONFIG_HAVE_HW_BREAKPOINTS */
682 release_thread(struct task_struct
*t
)
687 * This gets called before we allocate a new thread and copy
688 * the current task into it.
690 void prepare_to_copy(struct task_struct
*tsk
)
692 flush_fp_to_thread(current
);
693 flush_altivec_to_thread(current
);
694 flush_vsx_to_thread(current
);
695 flush_spe_to_thread(current
);
696 #ifdef CONFIG_HAVE_HW_BREAKPOINT
697 flush_ptrace_hw_breakpoint(tsk
);
698 #endif /* CONFIG_HAVE_HW_BREAKPOINT */
704 int copy_thread(unsigned long clone_flags
, unsigned long usp
,
705 unsigned long unused
, struct task_struct
*p
,
706 struct pt_regs
*regs
)
708 struct pt_regs
*childregs
, *kregs
;
709 extern void ret_from_fork(void);
710 unsigned long sp
= (unsigned long)task_stack_page(p
) + THREAD_SIZE
;
712 CHECK_FULL_REGS(regs
);
714 sp
-= sizeof(struct pt_regs
);
715 childregs
= (struct pt_regs
*) sp
;
717 if ((childregs
->msr
& MSR_PR
) == 0) {
718 /* for kernel thread, set `current' and stackptr in new task */
719 childregs
->gpr
[1] = sp
+ sizeof(struct pt_regs
);
721 childregs
->gpr
[2] = (unsigned long) p
;
723 clear_tsk_thread_flag(p
, TIF_32BIT
);
725 p
->thread
.regs
= NULL
; /* no user register state */
727 childregs
->gpr
[1] = usp
;
728 p
->thread
.regs
= childregs
;
729 if (clone_flags
& CLONE_SETTLS
) {
731 if (!test_thread_flag(TIF_32BIT
))
732 childregs
->gpr
[13] = childregs
->gpr
[6];
735 childregs
->gpr
[2] = childregs
->gpr
[6];
738 childregs
->gpr
[3] = 0; /* Result from fork() */
739 sp
-= STACK_FRAME_OVERHEAD
;
742 * The way this works is that at some point in the future
743 * some task will call _switch to switch to the new task.
744 * That will pop off the stack frame created below and start
745 * the new task running at ret_from_fork. The new task will
746 * do some house keeping and then return from the fork or clone
747 * system call, using the stack frame created above.
749 sp
-= sizeof(struct pt_regs
);
750 kregs
= (struct pt_regs
*) sp
;
751 sp
-= STACK_FRAME_OVERHEAD
;
753 p
->thread
.ksp_limit
= (unsigned long)task_stack_page(p
) +
754 _ALIGN_UP(sizeof(struct thread_info
), 16);
756 #ifdef CONFIG_PPC_STD_MMU_64
757 if (cpu_has_feature(CPU_FTR_SLB
)) {
758 unsigned long sp_vsid
;
759 unsigned long llp
= mmu_psize_defs
[mmu_linear_psize
].sllp
;
761 if (cpu_has_feature(CPU_FTR_1T_SEGMENT
))
762 sp_vsid
= get_kernel_vsid(sp
, MMU_SEGSIZE_1T
)
763 << SLB_VSID_SHIFT_1T
;
765 sp_vsid
= get_kernel_vsid(sp
, MMU_SEGSIZE_256M
)
767 sp_vsid
|= SLB_VSID_KERNEL
| llp
;
768 p
->thread
.ksp_vsid
= sp_vsid
;
770 #endif /* CONFIG_PPC_STD_MMU_64 */
773 * The PPC64 ABI makes use of a TOC to contain function
774 * pointers. The function (ret_from_except) is actually a pointer
775 * to the TOC entry. The first entry is a pointer to the actual
779 kregs
->nip
= *((unsigned long *)ret_from_fork
);
781 kregs
->nip
= (unsigned long)ret_from_fork
;
788 * Set up a thread for executing a new program
790 void start_thread(struct pt_regs
*regs
, unsigned long start
, unsigned long sp
)
793 unsigned long load_addr
= regs
->gpr
[2]; /* saved by ELF_PLAT_INIT */
799 * If we exec out of a kernel thread then thread.regs will not be
802 if (!current
->thread
.regs
) {
803 struct pt_regs
*regs
= task_stack_page(current
) + THREAD_SIZE
;
804 current
->thread
.regs
= regs
- 1;
807 memset(regs
->gpr
, 0, sizeof(regs
->gpr
));
815 * We have just cleared all the nonvolatile GPRs, so make
816 * FULL_REGS(regs) return true. This is necessary to allow
817 * ptrace to examine the thread immediately after exec.
824 regs
->msr
= MSR_USER
;
826 if (!test_thread_flag(TIF_32BIT
)) {
827 unsigned long entry
, toc
;
829 /* start is a relocated pointer to the function descriptor for
830 * the elf _start routine. The first entry in the function
831 * descriptor is the entry address of _start and the second
832 * entry is the TOC value we need to use.
834 __get_user(entry
, (unsigned long __user
*)start
);
835 __get_user(toc
, (unsigned long __user
*)start
+1);
837 /* Check whether the e_entry function descriptor entries
838 * need to be relocated before we can use them.
840 if (load_addr
!= 0) {
846 regs
->msr
= MSR_USER64
;
850 regs
->msr
= MSR_USER32
;
854 discard_lazy_cpu_state();
856 current
->thread
.used_vsr
= 0;
858 memset(current
->thread
.fpr
, 0, sizeof(current
->thread
.fpr
));
859 current
->thread
.fpscr
.val
= 0;
860 #ifdef CONFIG_ALTIVEC
861 memset(current
->thread
.vr
, 0, sizeof(current
->thread
.vr
));
862 memset(¤t
->thread
.vscr
, 0, sizeof(current
->thread
.vscr
));
863 current
->thread
.vscr
.u
[3] = 0x00010000; /* Java mode disabled */
864 current
->thread
.vrsave
= 0;
865 current
->thread
.used_vr
= 0;
866 #endif /* CONFIG_ALTIVEC */
868 memset(current
->thread
.evr
, 0, sizeof(current
->thread
.evr
));
869 current
->thread
.acc
= 0;
870 current
->thread
.spefscr
= 0;
871 current
->thread
.used_spe
= 0;
872 #endif /* CONFIG_SPE */
875 #define PR_FP_ALL_EXCEPT (PR_FP_EXC_DIV | PR_FP_EXC_OVF | PR_FP_EXC_UND \
876 | PR_FP_EXC_RES | PR_FP_EXC_INV)
878 int set_fpexc_mode(struct task_struct
*tsk
, unsigned int val
)
880 struct pt_regs
*regs
= tsk
->thread
.regs
;
882 /* This is a bit hairy. If we are an SPE enabled processor
883 * (have embedded fp) we store the IEEE exception enable flags in
884 * fpexc_mode. fpexc_mode is also used for setting FP exception
885 * mode (asyn, precise, disabled) for 'Classic' FP. */
886 if (val
& PR_FP_EXC_SW_ENABLE
) {
888 if (cpu_has_feature(CPU_FTR_SPE
)) {
889 tsk
->thread
.fpexc_mode
= val
&
890 (PR_FP_EXC_SW_ENABLE
| PR_FP_ALL_EXCEPT
);
900 /* on a CONFIG_SPE this does not hurt us. The bits that
901 * __pack_fe01 use do not overlap with bits used for
902 * PR_FP_EXC_SW_ENABLE. Additionally, the MSR[FE0,FE1] bits
903 * on CONFIG_SPE implementations are reserved so writing to
904 * them does not change anything */
905 if (val
> PR_FP_EXC_PRECISE
)
907 tsk
->thread
.fpexc_mode
= __pack_fe01(val
);
908 if (regs
!= NULL
&& (regs
->msr
& MSR_FP
) != 0)
909 regs
->msr
= (regs
->msr
& ~(MSR_FE0
|MSR_FE1
))
910 | tsk
->thread
.fpexc_mode
;
914 int get_fpexc_mode(struct task_struct
*tsk
, unsigned long adr
)
918 if (tsk
->thread
.fpexc_mode
& PR_FP_EXC_SW_ENABLE
)
920 if (cpu_has_feature(CPU_FTR_SPE
))
921 val
= tsk
->thread
.fpexc_mode
;
928 val
= __unpack_fe01(tsk
->thread
.fpexc_mode
);
929 return put_user(val
, (unsigned int __user
*) adr
);
932 int set_endian(struct task_struct
*tsk
, unsigned int val
)
934 struct pt_regs
*regs
= tsk
->thread
.regs
;
936 if ((val
== PR_ENDIAN_LITTLE
&& !cpu_has_feature(CPU_FTR_REAL_LE
)) ||
937 (val
== PR_ENDIAN_PPC_LITTLE
&& !cpu_has_feature(CPU_FTR_PPC_LE
)))
943 if (val
== PR_ENDIAN_BIG
)
944 regs
->msr
&= ~MSR_LE
;
945 else if (val
== PR_ENDIAN_LITTLE
|| val
== PR_ENDIAN_PPC_LITTLE
)
953 int get_endian(struct task_struct
*tsk
, unsigned long adr
)
955 struct pt_regs
*regs
= tsk
->thread
.regs
;
958 if (!cpu_has_feature(CPU_FTR_PPC_LE
) &&
959 !cpu_has_feature(CPU_FTR_REAL_LE
))
965 if (regs
->msr
& MSR_LE
) {
966 if (cpu_has_feature(CPU_FTR_REAL_LE
))
967 val
= PR_ENDIAN_LITTLE
;
969 val
= PR_ENDIAN_PPC_LITTLE
;
973 return put_user(val
, (unsigned int __user
*)adr
);
976 int set_unalign_ctl(struct task_struct
*tsk
, unsigned int val
)
978 tsk
->thread
.align_ctl
= val
;
982 int get_unalign_ctl(struct task_struct
*tsk
, unsigned long adr
)
984 return put_user(tsk
->thread
.align_ctl
, (unsigned int __user
*)adr
);
987 #define TRUNC_PTR(x) ((typeof(x))(((unsigned long)(x)) & 0xffffffff))
989 int sys_clone(unsigned long clone_flags
, unsigned long usp
,
990 int __user
*parent_tidp
, void __user
*child_threadptr
,
991 int __user
*child_tidp
, int p6
,
992 struct pt_regs
*regs
)
994 CHECK_FULL_REGS(regs
);
996 usp
= regs
->gpr
[1]; /* stack pointer for child */
998 if (test_thread_flag(TIF_32BIT
)) {
999 parent_tidp
= TRUNC_PTR(parent_tidp
);
1000 child_tidp
= TRUNC_PTR(child_tidp
);
1003 return do_fork(clone_flags
, usp
, regs
, 0, parent_tidp
, child_tidp
);
1006 int sys_fork(unsigned long p1
, unsigned long p2
, unsigned long p3
,
1007 unsigned long p4
, unsigned long p5
, unsigned long p6
,
1008 struct pt_regs
*regs
)
1010 CHECK_FULL_REGS(regs
);
1011 return do_fork(SIGCHLD
, regs
->gpr
[1], regs
, 0, NULL
, NULL
);
1014 int sys_vfork(unsigned long p1
, unsigned long p2
, unsigned long p3
,
1015 unsigned long p4
, unsigned long p5
, unsigned long p6
,
1016 struct pt_regs
*regs
)
1018 CHECK_FULL_REGS(regs
);
1019 return do_fork(CLONE_VFORK
| CLONE_VM
| SIGCHLD
, regs
->gpr
[1],
1020 regs
, 0, NULL
, NULL
);
1023 int sys_execve(unsigned long a0
, unsigned long a1
, unsigned long a2
,
1024 unsigned long a3
, unsigned long a4
, unsigned long a5
,
1025 struct pt_regs
*regs
)
1030 filename
= getname((const char __user
*) a0
);
1031 error
= PTR_ERR(filename
);
1032 if (IS_ERR(filename
))
1034 flush_fp_to_thread(current
);
1035 flush_altivec_to_thread(current
);
1036 flush_spe_to_thread(current
);
1037 error
= do_execve(filename
,
1038 (const char __user
*const __user
*) a1
,
1039 (const char __user
*const __user
*) a2
, regs
);
1045 static inline int valid_irq_stack(unsigned long sp
, struct task_struct
*p
,
1046 unsigned long nbytes
)
1048 unsigned long stack_page
;
1049 unsigned long cpu
= task_cpu(p
);
1052 * Avoid crashing if the stack has overflowed and corrupted
1053 * task_cpu(p), which is in the thread_info struct.
1055 if (cpu
< NR_CPUS
&& cpu_possible(cpu
)) {
1056 stack_page
= (unsigned long) hardirq_ctx
[cpu
];
1057 if (sp
>= stack_page
+ sizeof(struct thread_struct
)
1058 && sp
<= stack_page
+ THREAD_SIZE
- nbytes
)
1061 stack_page
= (unsigned long) softirq_ctx
[cpu
];
1062 if (sp
>= stack_page
+ sizeof(struct thread_struct
)
1063 && sp
<= stack_page
+ THREAD_SIZE
- nbytes
)
1069 int validate_sp(unsigned long sp
, struct task_struct
*p
,
1070 unsigned long nbytes
)
1072 unsigned long stack_page
= (unsigned long)task_stack_page(p
);
1074 if (sp
>= stack_page
+ sizeof(struct thread_struct
)
1075 && sp
<= stack_page
+ THREAD_SIZE
- nbytes
)
1078 return valid_irq_stack(sp
, p
, nbytes
);
1081 EXPORT_SYMBOL(validate_sp
);
1083 unsigned long get_wchan(struct task_struct
*p
)
1085 unsigned long ip
, sp
;
1088 if (!p
|| p
== current
|| p
->state
== TASK_RUNNING
)
1092 if (!validate_sp(sp
, p
, STACK_FRAME_OVERHEAD
))
1096 sp
= *(unsigned long *)sp
;
1097 if (!validate_sp(sp
, p
, STACK_FRAME_OVERHEAD
))
1100 ip
= ((unsigned long *)sp
)[STACK_FRAME_LR_SAVE
];
1101 if (!in_sched_functions(ip
))
1104 } while (count
++ < 16);
1108 static int kstack_depth_to_print
= CONFIG_PRINT_STACK_DEPTH
;
1110 void show_stack(struct task_struct
*tsk
, unsigned long *stack
)
1112 unsigned long sp
, ip
, lr
, newsp
;
1115 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1116 int curr_frame
= current
->curr_ret_stack
;
1117 extern void return_to_handler(void);
1118 unsigned long rth
= (unsigned long)return_to_handler
;
1119 unsigned long mrth
= -1;
1121 extern void mod_return_to_handler(void);
1122 rth
= *(unsigned long *)rth
;
1123 mrth
= (unsigned long)mod_return_to_handler
;
1124 mrth
= *(unsigned long *)mrth
;
1128 sp
= (unsigned long) stack
;
1133 asm("mr %0,1" : "=r" (sp
));
1135 sp
= tsk
->thread
.ksp
;
1139 printk("Call Trace:\n");
1141 if (!validate_sp(sp
, tsk
, STACK_FRAME_OVERHEAD
))
1144 stack
= (unsigned long *) sp
;
1146 ip
= stack
[STACK_FRAME_LR_SAVE
];
1147 if (!firstframe
|| ip
!= lr
) {
1148 printk("["REG
"] ["REG
"] %pS", sp
, ip
, (void *)ip
);
1149 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1150 if ((ip
== rth
|| ip
== mrth
) && curr_frame
>= 0) {
1152 (void *)current
->ret_stack
[curr_frame
].ret
);
1157 printk(" (unreliable)");
1163 * See if this is an exception frame.
1164 * We look for the "regshere" marker in the current frame.
1166 if (validate_sp(sp
, tsk
, STACK_INT_FRAME_SIZE
)
1167 && stack
[STACK_FRAME_MARKER
] == STACK_FRAME_REGS_MARKER
) {
1168 struct pt_regs
*regs
= (struct pt_regs
*)
1169 (sp
+ STACK_FRAME_OVERHEAD
);
1171 printk("--- Exception: %lx at %pS\n LR = %pS\n",
1172 regs
->trap
, (void *)regs
->nip
, (void *)lr
);
1177 } while (count
++ < kstack_depth_to_print
);
1180 void dump_stack(void)
1182 show_stack(current
, NULL
);
1184 EXPORT_SYMBOL(dump_stack
);
1187 void ppc64_runlatch_on(void)
1191 if (cpu_has_feature(CPU_FTR_CTRL
) && !test_thread_flag(TIF_RUNLATCH
)) {
1194 ctrl
= mfspr(SPRN_CTRLF
);
1195 ctrl
|= CTRL_RUNLATCH
;
1196 mtspr(SPRN_CTRLT
, ctrl
);
1198 set_thread_flag(TIF_RUNLATCH
);
1202 void ppc64_runlatch_off(void)
1206 if (cpu_has_feature(CPU_FTR_CTRL
) && test_thread_flag(TIF_RUNLATCH
)) {
1209 clear_thread_flag(TIF_RUNLATCH
);
1211 ctrl
= mfspr(SPRN_CTRLF
);
1212 ctrl
&= ~CTRL_RUNLATCH
;
1213 mtspr(SPRN_CTRLT
, ctrl
);
1218 #if THREAD_SHIFT < PAGE_SHIFT
1220 static struct kmem_cache
*thread_info_cache
;
1222 struct thread_info
*alloc_thread_info(struct task_struct
*tsk
)
1224 struct thread_info
*ti
;
1226 ti
= kmem_cache_alloc(thread_info_cache
, GFP_KERNEL
);
1227 if (unlikely(ti
== NULL
))
1229 #ifdef CONFIG_DEBUG_STACK_USAGE
1230 memset(ti
, 0, THREAD_SIZE
);
1235 void free_thread_info(struct thread_info
*ti
)
1237 kmem_cache_free(thread_info_cache
, ti
);
1240 void thread_info_cache_init(void)
1242 thread_info_cache
= kmem_cache_create("thread_info", THREAD_SIZE
,
1243 THREAD_SIZE
, 0, NULL
);
1244 BUG_ON(thread_info_cache
== NULL
);
1247 #endif /* THREAD_SHIFT < PAGE_SHIFT */
1249 unsigned long arch_align_stack(unsigned long sp
)
1251 if (!(current
->personality
& ADDR_NO_RANDOMIZE
) && randomize_va_space
)
1252 sp
-= get_random_int() & ~PAGE_MASK
;
1256 static inline unsigned long brk_rnd(void)
1258 unsigned long rnd
= 0;
1260 /* 8MB for 32bit, 1GB for 64bit */
1261 if (is_32bit_task())
1262 rnd
= (long)(get_random_int() % (1<<(23-PAGE_SHIFT
)));
1264 rnd
= (long)(get_random_int() % (1<<(30-PAGE_SHIFT
)));
1266 return rnd
<< PAGE_SHIFT
;
1269 unsigned long arch_randomize_brk(struct mm_struct
*mm
)
1271 unsigned long base
= mm
->brk
;
1274 #ifdef CONFIG_PPC_STD_MMU_64
1276 * If we are using 1TB segments and we are allowed to randomise
1277 * the heap, we can put it above 1TB so it is backed by a 1TB
1278 * segment. Otherwise the heap will be in the bottom 1TB
1279 * which always uses 256MB segments and this may result in a
1280 * performance penalty.
1282 if (!is_32bit_task() && (mmu_highuser_ssize
== MMU_SEGSIZE_1T
))
1283 base
= max_t(unsigned long, mm
->brk
, 1UL << SID_SHIFT_1T
);
1286 ret
= PAGE_ALIGN(base
+ brk_rnd());
1294 unsigned long randomize_et_dyn(unsigned long base
)
1296 unsigned long ret
= PAGE_ALIGN(base
+ brk_rnd());
1305 int arch_sd_sibling_asym_packing(void)
1307 if (cpu_has_feature(CPU_FTR_ASYM_SMT
)) {
1308 printk_once(KERN_INFO
"Enabling Asymmetric SMT scheduling\n");
1309 return SD_ASYM_PACKING
;