Remove obsolete #include <linux/config.h>
[linux-3.10.git] / arch / powerpc / kernel / process.c
1 /*
2  *  Derived from "arch/i386/kernel/process.c"
3  *    Copyright (C) 1995  Linus Torvalds
4  *
5  *  Updated and modified by Cort Dougan (cort@cs.nmt.edu) and
6  *  Paul Mackerras (paulus@cs.anu.edu.au)
7  *
8  *  PowerPC version
9  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
10  *
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.
15  */
16
17 #include <linux/errno.h>
18 #include <linux/sched.h>
19 #include <linux/kernel.h>
20 #include <linux/mm.h>
21 #include <linux/smp.h>
22 #include <linux/smp_lock.h>
23 #include <linux/stddef.h>
24 #include <linux/unistd.h>
25 #include <linux/ptrace.h>
26 #include <linux/slab.h>
27 #include <linux/user.h>
28 #include <linux/elf.h>
29 #include <linux/init.h>
30 #include <linux/prctl.h>
31 #include <linux/init_task.h>
32 #include <linux/module.h>
33 #include <linux/kallsyms.h>
34 #include <linux/mqueue.h>
35 #include <linux/hardirq.h>
36 #include <linux/utsname.h>
37
38 #include <asm/pgtable.h>
39 #include <asm/uaccess.h>
40 #include <asm/system.h>
41 #include <asm/io.h>
42 #include <asm/processor.h>
43 #include <asm/mmu.h>
44 #include <asm/prom.h>
45 #include <asm/machdep.h>
46 #include <asm/time.h>
47 #include <asm/syscalls.h>
48 #ifdef CONFIG_PPC64
49 #include <asm/firmware.h>
50 #endif
51
52 extern unsigned long _get_SP(void);
53
54 #ifndef CONFIG_SMP
55 struct task_struct *last_task_used_math = NULL;
56 struct task_struct *last_task_used_altivec = NULL;
57 struct task_struct *last_task_used_spe = NULL;
58 #endif
59
60 /*
61  * Make sure the floating-point register state in the
62  * the thread_struct is up to date for task tsk.
63  */
64 void flush_fp_to_thread(struct task_struct *tsk)
65 {
66         if (tsk->thread.regs) {
67                 /*
68                  * We need to disable preemption here because if we didn't,
69                  * another process could get scheduled after the regs->msr
70                  * test but before we have finished saving the FP registers
71                  * to the thread_struct.  That process could take over the
72                  * FPU, and then when we get scheduled again we would store
73                  * bogus values for the remaining FP registers.
74                  */
75                 preempt_disable();
76                 if (tsk->thread.regs->msr & MSR_FP) {
77 #ifdef CONFIG_SMP
78                         /*
79                          * This should only ever be called for current or
80                          * for a stopped child process.  Since we save away
81                          * the FP register state on context switch on SMP,
82                          * there is something wrong if a stopped child appears
83                          * to still have its FP state in the CPU registers.
84                          */
85                         BUG_ON(tsk != current);
86 #endif
87                         giveup_fpu(current);
88                 }
89                 preempt_enable();
90         }
91 }
92
93 void enable_kernel_fp(void)
94 {
95         WARN_ON(preemptible());
96
97 #ifdef CONFIG_SMP
98         if (current->thread.regs && (current->thread.regs->msr & MSR_FP))
99                 giveup_fpu(current);
100         else
101                 giveup_fpu(NULL);       /* just enables FP for kernel */
102 #else
103         giveup_fpu(last_task_used_math);
104 #endif /* CONFIG_SMP */
105 }
106 EXPORT_SYMBOL(enable_kernel_fp);
107
108 int dump_task_fpu(struct task_struct *tsk, elf_fpregset_t *fpregs)
109 {
110         if (!tsk->thread.regs)
111                 return 0;
112         flush_fp_to_thread(current);
113
114         memcpy(fpregs, &tsk->thread.fpr[0], sizeof(*fpregs));
115
116         return 1;
117 }
118
119 #ifdef CONFIG_ALTIVEC
120 void enable_kernel_altivec(void)
121 {
122         WARN_ON(preemptible());
123
124 #ifdef CONFIG_SMP
125         if (current->thread.regs && (current->thread.regs->msr & MSR_VEC))
126                 giveup_altivec(current);
127         else
128                 giveup_altivec(NULL);   /* just enable AltiVec for kernel - force */
129 #else
130         giveup_altivec(last_task_used_altivec);
131 #endif /* CONFIG_SMP */
132 }
133 EXPORT_SYMBOL(enable_kernel_altivec);
134
135 /*
136  * Make sure the VMX/Altivec register state in the
137  * the thread_struct is up to date for task tsk.
138  */
139 void flush_altivec_to_thread(struct task_struct *tsk)
140 {
141         if (tsk->thread.regs) {
142                 preempt_disable();
143                 if (tsk->thread.regs->msr & MSR_VEC) {
144 #ifdef CONFIG_SMP
145                         BUG_ON(tsk != current);
146 #endif
147                         giveup_altivec(current);
148                 }
149                 preempt_enable();
150         }
151 }
152
153 int dump_task_altivec(struct pt_regs *regs, elf_vrregset_t *vrregs)
154 {
155         flush_altivec_to_thread(current);
156         memcpy(vrregs, &current->thread.vr[0], sizeof(*vrregs));
157         return 1;
158 }
159 #endif /* CONFIG_ALTIVEC */
160
161 #ifdef CONFIG_SPE
162
163 void enable_kernel_spe(void)
164 {
165         WARN_ON(preemptible());
166
167 #ifdef CONFIG_SMP
168         if (current->thread.regs && (current->thread.regs->msr & MSR_SPE))
169                 giveup_spe(current);
170         else
171                 giveup_spe(NULL);       /* just enable SPE for kernel - force */
172 #else
173         giveup_spe(last_task_used_spe);
174 #endif /* __SMP __ */
175 }
176 EXPORT_SYMBOL(enable_kernel_spe);
177
178 void flush_spe_to_thread(struct task_struct *tsk)
179 {
180         if (tsk->thread.regs) {
181                 preempt_disable();
182                 if (tsk->thread.regs->msr & MSR_SPE) {
183 #ifdef CONFIG_SMP
184                         BUG_ON(tsk != current);
185 #endif
186                         giveup_spe(current);
187                 }
188                 preempt_enable();
189         }
190 }
191
192 int dump_spe(struct pt_regs *regs, elf_vrregset_t *evrregs)
193 {
194         flush_spe_to_thread(current);
195         /* We copy u32 evr[32] + u64 acc + u32 spefscr -> 35 */
196         memcpy(evrregs, &current->thread.evr[0], sizeof(u32) * 35);
197         return 1;
198 }
199 #endif /* CONFIG_SPE */
200
201 #ifndef CONFIG_SMP
202 /*
203  * If we are doing lazy switching of CPU state (FP, altivec or SPE),
204  * and the current task has some state, discard it.
205  */
206 void discard_lazy_cpu_state(void)
207 {
208         preempt_disable();
209         if (last_task_used_math == current)
210                 last_task_used_math = NULL;
211 #ifdef CONFIG_ALTIVEC
212         if (last_task_used_altivec == current)
213                 last_task_used_altivec = NULL;
214 #endif /* CONFIG_ALTIVEC */
215 #ifdef CONFIG_SPE
216         if (last_task_used_spe == current)
217                 last_task_used_spe = NULL;
218 #endif
219         preempt_enable();
220 }
221 #endif /* CONFIG_SMP */
222
223 #ifdef CONFIG_PPC_MERGE         /* XXX for now */
224 int set_dabr(unsigned long dabr)
225 {
226         if (ppc_md.set_dabr)
227                 return ppc_md.set_dabr(dabr);
228
229         mtspr(SPRN_DABR, dabr);
230         return 0;
231 }
232 #endif
233
234 #ifdef CONFIG_PPC64
235 DEFINE_PER_CPU(struct cpu_usage, cpu_usage_array);
236 static DEFINE_PER_CPU(unsigned long, current_dabr);
237 #endif
238
239 struct task_struct *__switch_to(struct task_struct *prev,
240         struct task_struct *new)
241 {
242         struct thread_struct *new_thread, *old_thread;
243         unsigned long flags;
244         struct task_struct *last;
245
246 #ifdef CONFIG_SMP
247         /* avoid complexity of lazy save/restore of fpu
248          * by just saving it every time we switch out if
249          * this task used the fpu during the last quantum.
250          *
251          * If it tries to use the fpu again, it'll trap and
252          * reload its fp regs.  So we don't have to do a restore
253          * every switch, just a save.
254          *  -- Cort
255          */
256         if (prev->thread.regs && (prev->thread.regs->msr & MSR_FP))
257                 giveup_fpu(prev);
258 #ifdef CONFIG_ALTIVEC
259         /*
260          * If the previous thread used altivec in the last quantum
261          * (thus changing altivec regs) then save them.
262          * We used to check the VRSAVE register but not all apps
263          * set it, so we don't rely on it now (and in fact we need
264          * to save & restore VSCR even if VRSAVE == 0).  -- paulus
265          *
266          * On SMP we always save/restore altivec regs just to avoid the
267          * complexity of changing processors.
268          *  -- Cort
269          */
270         if (prev->thread.regs && (prev->thread.regs->msr & MSR_VEC))
271                 giveup_altivec(prev);
272 #endif /* CONFIG_ALTIVEC */
273 #ifdef CONFIG_SPE
274         /*
275          * If the previous thread used spe in the last quantum
276          * (thus changing spe regs) then save them.
277          *
278          * On SMP we always save/restore spe regs just to avoid the
279          * complexity of changing processors.
280          */
281         if ((prev->thread.regs && (prev->thread.regs->msr & MSR_SPE)))
282                 giveup_spe(prev);
283 #endif /* CONFIG_SPE */
284
285 #else  /* CONFIG_SMP */
286 #ifdef CONFIG_ALTIVEC
287         /* Avoid the trap.  On smp this this never happens since
288          * we don't set last_task_used_altivec -- Cort
289          */
290         if (new->thread.regs && last_task_used_altivec == new)
291                 new->thread.regs->msr |= MSR_VEC;
292 #endif /* CONFIG_ALTIVEC */
293 #ifdef CONFIG_SPE
294         /* Avoid the trap.  On smp this this never happens since
295          * we don't set last_task_used_spe
296          */
297         if (new->thread.regs && last_task_used_spe == new)
298                 new->thread.regs->msr |= MSR_SPE;
299 #endif /* CONFIG_SPE */
300
301 #endif /* CONFIG_SMP */
302
303 #ifdef CONFIG_PPC64     /* for now */
304         if (unlikely(__get_cpu_var(current_dabr) != new->thread.dabr)) {
305                 set_dabr(new->thread.dabr);
306                 __get_cpu_var(current_dabr) = new->thread.dabr;
307         }
308
309         flush_tlb_pending();
310 #endif
311
312         new_thread = &new->thread;
313         old_thread = &current->thread;
314
315 #ifdef CONFIG_PPC64
316         /*
317          * Collect processor utilization data per process
318          */
319         if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
320                 struct cpu_usage *cu = &__get_cpu_var(cpu_usage_array);
321                 long unsigned start_tb, current_tb;
322                 start_tb = old_thread->start_tb;
323                 cu->current_tb = current_tb = mfspr(SPRN_PURR);
324                 old_thread->accum_tb += (current_tb - start_tb);
325                 new_thread->start_tb = current_tb;
326         }
327 #endif
328
329         local_irq_save(flags);
330
331         account_system_vtime(current);
332         account_process_vtime(current);
333         calculate_steal_time();
334
335         last = _switch(old_thread, new_thread);
336
337         local_irq_restore(flags);
338
339         return last;
340 }
341
342 static int instructions_to_print = 16;
343
344 #ifdef CONFIG_PPC64
345 #define BAD_PC(pc)      ((REGION_ID(pc) != KERNEL_REGION_ID) && \
346                          (REGION_ID(pc) != VMALLOC_REGION_ID))
347 #else
348 #define BAD_PC(pc)      ((pc) < KERNELBASE)
349 #endif
350
351 static void show_instructions(struct pt_regs *regs)
352 {
353         int i;
354         unsigned long pc = regs->nip - (instructions_to_print * 3 / 4 *
355                         sizeof(int));
356
357         printk("Instruction dump:");
358
359         for (i = 0; i < instructions_to_print; i++) {
360                 int instr;
361
362                 if (!(i % 8))
363                         printk("\n");
364
365                 /* We use __get_user here *only* to avoid an OOPS on a
366                  * bad address because the pc *should* only be a
367                  * kernel address.
368                  */
369                 if (BAD_PC(pc) || __get_user(instr, (unsigned int __user *)pc)) {
370                         printk("XXXXXXXX ");
371                 } else {
372                         if (regs->nip == pc)
373                                 printk("<%08x> ", instr);
374                         else
375                                 printk("%08x ", instr);
376                 }
377
378                 pc += sizeof(int);
379         }
380
381         printk("\n");
382 }
383
384 static struct regbit {
385         unsigned long bit;
386         const char *name;
387 } msr_bits[] = {
388         {MSR_EE,        "EE"},
389         {MSR_PR,        "PR"},
390         {MSR_FP,        "FP"},
391         {MSR_ME,        "ME"},
392         {MSR_IR,        "IR"},
393         {MSR_DR,        "DR"},
394         {0,             NULL}
395 };
396
397 static void printbits(unsigned long val, struct regbit *bits)
398 {
399         const char *sep = "";
400
401         printk("<");
402         for (; bits->bit; ++bits)
403                 if (val & bits->bit) {
404                         printk("%s%s", sep, bits->name);
405                         sep = ",";
406                 }
407         printk(">");
408 }
409
410 #ifdef CONFIG_PPC64
411 #define REG             "%016lX"
412 #define REGS_PER_LINE   4
413 #define LAST_VOLATILE   13
414 #else
415 #define REG             "%08lX"
416 #define REGS_PER_LINE   8
417 #define LAST_VOLATILE   12
418 #endif
419
420 void show_regs(struct pt_regs * regs)
421 {
422         int i, trap;
423
424         printk("NIP: "REG" LR: "REG" CTR: "REG"\n",
425                regs->nip, regs->link, regs->ctr);
426         printk("REGS: %p TRAP: %04lx   %s  (%s)\n",
427                regs, regs->trap, print_tainted(), system_utsname.release);
428         printk("MSR: "REG" ", regs->msr);
429         printbits(regs->msr, msr_bits);
430         printk("  CR: %08lX  XER: %08lX\n", regs->ccr, regs->xer);
431         trap = TRAP(regs);
432         if (trap == 0x300 || trap == 0x600)
433                 printk("DAR: "REG", DSISR: "REG"\n", regs->dar, regs->dsisr);
434         printk("TASK = %p[%d] '%s' THREAD: %p",
435                current, current->pid, current->comm, task_thread_info(current));
436
437 #ifdef CONFIG_SMP
438         printk(" CPU: %d", smp_processor_id());
439 #endif /* CONFIG_SMP */
440
441         for (i = 0;  i < 32;  i++) {
442                 if ((i % REGS_PER_LINE) == 0)
443                         printk("\n" KERN_INFO "GPR%02d: ", i);
444                 printk(REG " ", regs->gpr[i]);
445                 if (i == LAST_VOLATILE && !FULL_REGS(regs))
446                         break;
447         }
448         printk("\n");
449 #ifdef CONFIG_KALLSYMS
450         /*
451          * Lookup NIP late so we have the best change of getting the
452          * above info out without failing
453          */
454         printk("NIP ["REG"] ", regs->nip);
455         print_symbol("%s\n", regs->nip);
456         printk("LR ["REG"] ", regs->link);
457         print_symbol("%s\n", regs->link);
458 #endif
459         show_stack(current, (unsigned long *) regs->gpr[1]);
460         if (!user_mode(regs))
461                 show_instructions(regs);
462 }
463
464 void exit_thread(void)
465 {
466         discard_lazy_cpu_state();
467 }
468
469 void flush_thread(void)
470 {
471 #ifdef CONFIG_PPC64
472         struct thread_info *t = current_thread_info();
473
474         if (t->flags & _TIF_ABI_PENDING)
475                 t->flags ^= (_TIF_ABI_PENDING | _TIF_32BIT);
476 #endif
477
478         discard_lazy_cpu_state();
479
480 #ifdef CONFIG_PPC64     /* for now */
481         if (current->thread.dabr) {
482                 current->thread.dabr = 0;
483                 set_dabr(0);
484         }
485 #endif
486 }
487
488 void
489 release_thread(struct task_struct *t)
490 {
491 }
492
493 /*
494  * This gets called before we allocate a new thread and copy
495  * the current task into it.
496  */
497 void prepare_to_copy(struct task_struct *tsk)
498 {
499         flush_fp_to_thread(current);
500         flush_altivec_to_thread(current);
501         flush_spe_to_thread(current);
502 }
503
504 /*
505  * Copy a thread..
506  */
507 int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
508                 unsigned long unused, struct task_struct *p,
509                 struct pt_regs *regs)
510 {
511         struct pt_regs *childregs, *kregs;
512         extern void ret_from_fork(void);
513         unsigned long sp = (unsigned long)task_stack_page(p) + THREAD_SIZE;
514
515         CHECK_FULL_REGS(regs);
516         /* Copy registers */
517         sp -= sizeof(struct pt_regs);
518         childregs = (struct pt_regs *) sp;
519         *childregs = *regs;
520         if ((childregs->msr & MSR_PR) == 0) {
521                 /* for kernel thread, set `current' and stackptr in new task */
522                 childregs->gpr[1] = sp + sizeof(struct pt_regs);
523 #ifdef CONFIG_PPC32
524                 childregs->gpr[2] = (unsigned long) p;
525 #else
526                 clear_tsk_thread_flag(p, TIF_32BIT);
527 #endif
528                 p->thread.regs = NULL;  /* no user register state */
529         } else {
530                 childregs->gpr[1] = usp;
531                 p->thread.regs = childregs;
532                 if (clone_flags & CLONE_SETTLS) {
533 #ifdef CONFIG_PPC64
534                         if (!test_thread_flag(TIF_32BIT))
535                                 childregs->gpr[13] = childregs->gpr[6];
536                         else
537 #endif
538                                 childregs->gpr[2] = childregs->gpr[6];
539                 }
540         }
541         childregs->gpr[3] = 0;  /* Result from fork() */
542         sp -= STACK_FRAME_OVERHEAD;
543
544         /*
545          * The way this works is that at some point in the future
546          * some task will call _switch to switch to the new task.
547          * That will pop off the stack frame created below and start
548          * the new task running at ret_from_fork.  The new task will
549          * do some house keeping and then return from the fork or clone
550          * system call, using the stack frame created above.
551          */
552         sp -= sizeof(struct pt_regs);
553         kregs = (struct pt_regs *) sp;
554         sp -= STACK_FRAME_OVERHEAD;
555         p->thread.ksp = sp;
556
557 #ifdef CONFIG_PPC64
558         if (cpu_has_feature(CPU_FTR_SLB)) {
559                 unsigned long sp_vsid = get_kernel_vsid(sp);
560                 unsigned long llp = mmu_psize_defs[mmu_linear_psize].sllp;
561
562                 sp_vsid <<= SLB_VSID_SHIFT;
563                 sp_vsid |= SLB_VSID_KERNEL | llp;
564                 p->thread.ksp_vsid = sp_vsid;
565         }
566
567         /*
568          * The PPC64 ABI makes use of a TOC to contain function 
569          * pointers.  The function (ret_from_except) is actually a pointer
570          * to the TOC entry.  The first entry is a pointer to the actual
571          * function.
572          */
573         kregs->nip = *((unsigned long *)ret_from_fork);
574 #else
575         kregs->nip = (unsigned long)ret_from_fork;
576         p->thread.last_syscall = -1;
577 #endif
578
579         return 0;
580 }
581
582 /*
583  * Set up a thread for executing a new program
584  */
585 void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp)
586 {
587 #ifdef CONFIG_PPC64
588         unsigned long load_addr = regs->gpr[2]; /* saved by ELF_PLAT_INIT */
589 #endif
590
591         set_fs(USER_DS);
592
593         /*
594          * If we exec out of a kernel thread then thread.regs will not be
595          * set.  Do it now.
596          */
597         if (!current->thread.regs) {
598                 struct pt_regs *regs = task_stack_page(current) + THREAD_SIZE;
599                 current->thread.regs = regs - 1;
600         }
601
602         memset(regs->gpr, 0, sizeof(regs->gpr));
603         regs->ctr = 0;
604         regs->link = 0;
605         regs->xer = 0;
606         regs->ccr = 0;
607         regs->gpr[1] = sp;
608
609 #ifdef CONFIG_PPC32
610         regs->mq = 0;
611         regs->nip = start;
612         regs->msr = MSR_USER;
613 #else
614         if (!test_thread_flag(TIF_32BIT)) {
615                 unsigned long entry, toc;
616
617                 /* start is a relocated pointer to the function descriptor for
618                  * the elf _start routine.  The first entry in the function
619                  * descriptor is the entry address of _start and the second
620                  * entry is the TOC value we need to use.
621                  */
622                 __get_user(entry, (unsigned long __user *)start);
623                 __get_user(toc, (unsigned long __user *)start+1);
624
625                 /* Check whether the e_entry function descriptor entries
626                  * need to be relocated before we can use them.
627                  */
628                 if (load_addr != 0) {
629                         entry += load_addr;
630                         toc   += load_addr;
631                 }
632                 regs->nip = entry;
633                 regs->gpr[2] = toc;
634                 regs->msr = MSR_USER64;
635         } else {
636                 regs->nip = start;
637                 regs->gpr[2] = 0;
638                 regs->msr = MSR_USER32;
639         }
640 #endif
641
642         discard_lazy_cpu_state();
643         memset(current->thread.fpr, 0, sizeof(current->thread.fpr));
644         current->thread.fpscr.val = 0;
645 #ifdef CONFIG_ALTIVEC
646         memset(current->thread.vr, 0, sizeof(current->thread.vr));
647         memset(&current->thread.vscr, 0, sizeof(current->thread.vscr));
648         current->thread.vscr.u[3] = 0x00010000; /* Java mode disabled */
649         current->thread.vrsave = 0;
650         current->thread.used_vr = 0;
651 #endif /* CONFIG_ALTIVEC */
652 #ifdef CONFIG_SPE
653         memset(current->thread.evr, 0, sizeof(current->thread.evr));
654         current->thread.acc = 0;
655         current->thread.spefscr = 0;
656         current->thread.used_spe = 0;
657 #endif /* CONFIG_SPE */
658 }
659
660 #define PR_FP_ALL_EXCEPT (PR_FP_EXC_DIV | PR_FP_EXC_OVF | PR_FP_EXC_UND \
661                 | PR_FP_EXC_RES | PR_FP_EXC_INV)
662
663 int set_fpexc_mode(struct task_struct *tsk, unsigned int val)
664 {
665         struct pt_regs *regs = tsk->thread.regs;
666
667         /* This is a bit hairy.  If we are an SPE enabled  processor
668          * (have embedded fp) we store the IEEE exception enable flags in
669          * fpexc_mode.  fpexc_mode is also used for setting FP exception
670          * mode (asyn, precise, disabled) for 'Classic' FP. */
671         if (val & PR_FP_EXC_SW_ENABLE) {
672 #ifdef CONFIG_SPE
673                 tsk->thread.fpexc_mode = val &
674                         (PR_FP_EXC_SW_ENABLE | PR_FP_ALL_EXCEPT);
675                 return 0;
676 #else
677                 return -EINVAL;
678 #endif
679         }
680
681         /* on a CONFIG_SPE this does not hurt us.  The bits that
682          * __pack_fe01 use do not overlap with bits used for
683          * PR_FP_EXC_SW_ENABLE.  Additionally, the MSR[FE0,FE1] bits
684          * on CONFIG_SPE implementations are reserved so writing to
685          * them does not change anything */
686         if (val > PR_FP_EXC_PRECISE)
687                 return -EINVAL;
688         tsk->thread.fpexc_mode = __pack_fe01(val);
689         if (regs != NULL && (regs->msr & MSR_FP) != 0)
690                 regs->msr = (regs->msr & ~(MSR_FE0|MSR_FE1))
691                         | tsk->thread.fpexc_mode;
692         return 0;
693 }
694
695 int get_fpexc_mode(struct task_struct *tsk, unsigned long adr)
696 {
697         unsigned int val;
698
699         if (tsk->thread.fpexc_mode & PR_FP_EXC_SW_ENABLE)
700 #ifdef CONFIG_SPE
701                 val = tsk->thread.fpexc_mode;
702 #else
703                 return -EINVAL;
704 #endif
705         else
706                 val = __unpack_fe01(tsk->thread.fpexc_mode);
707         return put_user(val, (unsigned int __user *) adr);
708 }
709
710 int set_endian(struct task_struct *tsk, unsigned int val)
711 {
712         struct pt_regs *regs = tsk->thread.regs;
713
714         if ((val == PR_ENDIAN_LITTLE && !cpu_has_feature(CPU_FTR_REAL_LE)) ||
715             (val == PR_ENDIAN_PPC_LITTLE && !cpu_has_feature(CPU_FTR_PPC_LE)))
716                 return -EINVAL;
717
718         if (regs == NULL)
719                 return -EINVAL;
720
721         if (val == PR_ENDIAN_BIG)
722                 regs->msr &= ~MSR_LE;
723         else if (val == PR_ENDIAN_LITTLE || val == PR_ENDIAN_PPC_LITTLE)
724                 regs->msr |= MSR_LE;
725         else
726                 return -EINVAL;
727
728         return 0;
729 }
730
731 int get_endian(struct task_struct *tsk, unsigned long adr)
732 {
733         struct pt_regs *regs = tsk->thread.regs;
734         unsigned int val;
735
736         if (!cpu_has_feature(CPU_FTR_PPC_LE) &&
737             !cpu_has_feature(CPU_FTR_REAL_LE))
738                 return -EINVAL;
739
740         if (regs == NULL)
741                 return -EINVAL;
742
743         if (regs->msr & MSR_LE) {
744                 if (cpu_has_feature(CPU_FTR_REAL_LE))
745                         val = PR_ENDIAN_LITTLE;
746                 else
747                         val = PR_ENDIAN_PPC_LITTLE;
748         } else
749                 val = PR_ENDIAN_BIG;
750
751         return put_user(val, (unsigned int __user *)adr);
752 }
753
754 int set_unalign_ctl(struct task_struct *tsk, unsigned int val)
755 {
756         tsk->thread.align_ctl = val;
757         return 0;
758 }
759
760 int get_unalign_ctl(struct task_struct *tsk, unsigned long adr)
761 {
762         return put_user(tsk->thread.align_ctl, (unsigned int __user *)adr);
763 }
764
765 #define TRUNC_PTR(x)    ((typeof(x))(((unsigned long)(x)) & 0xffffffff))
766
767 int sys_clone(unsigned long clone_flags, unsigned long usp,
768               int __user *parent_tidp, void __user *child_threadptr,
769               int __user *child_tidp, int p6,
770               struct pt_regs *regs)
771 {
772         CHECK_FULL_REGS(regs);
773         if (usp == 0)
774                 usp = regs->gpr[1];     /* stack pointer for child */
775 #ifdef CONFIG_PPC64
776         if (test_thread_flag(TIF_32BIT)) {
777                 parent_tidp = TRUNC_PTR(parent_tidp);
778                 child_tidp = TRUNC_PTR(child_tidp);
779         }
780 #endif
781         return do_fork(clone_flags, usp, regs, 0, parent_tidp, child_tidp);
782 }
783
784 int sys_fork(unsigned long p1, unsigned long p2, unsigned long p3,
785              unsigned long p4, unsigned long p5, unsigned long p6,
786              struct pt_regs *regs)
787 {
788         CHECK_FULL_REGS(regs);
789         return do_fork(SIGCHLD, regs->gpr[1], regs, 0, NULL, NULL);
790 }
791
792 int sys_vfork(unsigned long p1, unsigned long p2, unsigned long p3,
793               unsigned long p4, unsigned long p5, unsigned long p6,
794               struct pt_regs *regs)
795 {
796         CHECK_FULL_REGS(regs);
797         return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->gpr[1],
798                         regs, 0, NULL, NULL);
799 }
800
801 int sys_execve(unsigned long a0, unsigned long a1, unsigned long a2,
802                unsigned long a3, unsigned long a4, unsigned long a5,
803                struct pt_regs *regs)
804 {
805         int error;
806         char *filename;
807
808         filename = getname((char __user *) a0);
809         error = PTR_ERR(filename);
810         if (IS_ERR(filename))
811                 goto out;
812         flush_fp_to_thread(current);
813         flush_altivec_to_thread(current);
814         flush_spe_to_thread(current);
815         error = do_execve(filename, (char __user * __user *) a1,
816                           (char __user * __user *) a2, regs);
817         if (error == 0) {
818                 task_lock(current);
819                 current->ptrace &= ~PT_DTRACE;
820                 task_unlock(current);
821         }
822         putname(filename);
823 out:
824         return error;
825 }
826
827 int validate_sp(unsigned long sp, struct task_struct *p,
828                        unsigned long nbytes)
829 {
830         unsigned long stack_page = (unsigned long)task_stack_page(p);
831
832         if (sp >= stack_page + sizeof(struct thread_struct)
833             && sp <= stack_page + THREAD_SIZE - nbytes)
834                 return 1;
835
836 #ifdef CONFIG_IRQSTACKS
837         stack_page = (unsigned long) hardirq_ctx[task_cpu(p)];
838         if (sp >= stack_page + sizeof(struct thread_struct)
839             && sp <= stack_page + THREAD_SIZE - nbytes)
840                 return 1;
841
842         stack_page = (unsigned long) softirq_ctx[task_cpu(p)];
843         if (sp >= stack_page + sizeof(struct thread_struct)
844             && sp <= stack_page + THREAD_SIZE - nbytes)
845                 return 1;
846 #endif
847
848         return 0;
849 }
850
851 #ifdef CONFIG_PPC64
852 #define MIN_STACK_FRAME 112     /* same as STACK_FRAME_OVERHEAD, in fact */
853 #define FRAME_LR_SAVE   2
854 #define INT_FRAME_SIZE  (sizeof(struct pt_regs) + STACK_FRAME_OVERHEAD + 288)
855 #define REGS_MARKER     0x7265677368657265ul
856 #define FRAME_MARKER    12
857 #else
858 #define MIN_STACK_FRAME 16
859 #define FRAME_LR_SAVE   1
860 #define INT_FRAME_SIZE  (sizeof(struct pt_regs) + STACK_FRAME_OVERHEAD)
861 #define REGS_MARKER     0x72656773ul
862 #define FRAME_MARKER    2
863 #endif
864
865 EXPORT_SYMBOL(validate_sp);
866
867 unsigned long get_wchan(struct task_struct *p)
868 {
869         unsigned long ip, sp;
870         int count = 0;
871
872         if (!p || p == current || p->state == TASK_RUNNING)
873                 return 0;
874
875         sp = p->thread.ksp;
876         if (!validate_sp(sp, p, MIN_STACK_FRAME))
877                 return 0;
878
879         do {
880                 sp = *(unsigned long *)sp;
881                 if (!validate_sp(sp, p, MIN_STACK_FRAME))
882                         return 0;
883                 if (count > 0) {
884                         ip = ((unsigned long *)sp)[FRAME_LR_SAVE];
885                         if (!in_sched_functions(ip))
886                                 return ip;
887                 }
888         } while (count++ < 16);
889         return 0;
890 }
891
892 static int kstack_depth_to_print = 64;
893
894 void show_stack(struct task_struct *tsk, unsigned long *stack)
895 {
896         unsigned long sp, ip, lr, newsp;
897         int count = 0;
898         int firstframe = 1;
899
900         sp = (unsigned long) stack;
901         if (tsk == NULL)
902                 tsk = current;
903         if (sp == 0) {
904                 if (tsk == current)
905                         asm("mr %0,1" : "=r" (sp));
906                 else
907                         sp = tsk->thread.ksp;
908         }
909
910         lr = 0;
911         printk("Call Trace:\n");
912         do {
913                 if (!validate_sp(sp, tsk, MIN_STACK_FRAME))
914                         return;
915
916                 stack = (unsigned long *) sp;
917                 newsp = stack[0];
918                 ip = stack[FRAME_LR_SAVE];
919                 if (!firstframe || ip != lr) {
920                         printk("["REG"] ["REG"] ", sp, ip);
921                         print_symbol("%s", ip);
922                         if (firstframe)
923                                 printk(" (unreliable)");
924                         printk("\n");
925                 }
926                 firstframe = 0;
927
928                 /*
929                  * See if this is an exception frame.
930                  * We look for the "regshere" marker in the current frame.
931                  */
932                 if (validate_sp(sp, tsk, INT_FRAME_SIZE)
933                     && stack[FRAME_MARKER] == REGS_MARKER) {
934                         struct pt_regs *regs = (struct pt_regs *)
935                                 (sp + STACK_FRAME_OVERHEAD);
936                         printk("--- Exception: %lx", regs->trap);
937                         print_symbol(" at %s\n", regs->nip);
938                         lr = regs->link;
939                         print_symbol("    LR = %s\n", lr);
940                         firstframe = 1;
941                 }
942
943                 sp = newsp;
944         } while (count++ < kstack_depth_to_print);
945 }
946
947 void dump_stack(void)
948 {
949         show_stack(current, NULL);
950 }
951 EXPORT_SYMBOL(dump_stack);
952
953 #ifdef CONFIG_PPC64
954 void ppc64_runlatch_on(void)
955 {
956         unsigned long ctrl;
957
958         if (cpu_has_feature(CPU_FTR_CTRL) && !test_thread_flag(TIF_RUNLATCH)) {
959                 HMT_medium();
960
961                 ctrl = mfspr(SPRN_CTRLF);
962                 ctrl |= CTRL_RUNLATCH;
963                 mtspr(SPRN_CTRLT, ctrl);
964
965                 set_thread_flag(TIF_RUNLATCH);
966         }
967 }
968
969 void ppc64_runlatch_off(void)
970 {
971         unsigned long ctrl;
972
973         if (cpu_has_feature(CPU_FTR_CTRL) && test_thread_flag(TIF_RUNLATCH)) {
974                 HMT_medium();
975
976                 clear_thread_flag(TIF_RUNLATCH);
977
978                 ctrl = mfspr(SPRN_CTRLF);
979                 ctrl &= ~CTRL_RUNLATCH;
980                 mtspr(SPRN_CTRLT, ctrl);
981         }
982 }
983 #endif