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Merge master.kernel.org:/pub/scm/linux/kernel/git/mchehab/v4l-dvb
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / powerpc / kernel / process.c
CommitLineData
14cf11af
PM		 1/*
2 * arch/ppc/kernel/process.c
3 *
4 * Derived from "arch/i386/kernel/process.c"
5 * Copyright (C) 1995 Linus Torvalds
6 *
7 * Updated and modified by Cort Dougan (cort@cs.nmt.edu) and
8 * Paul Mackerras (paulus@cs.anu.edu.au)
9 *
10 * PowerPC version
11 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
12 *
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License
15 * as published by the Free Software Foundation; either version
16 * 2 of the License, or (at your option) any later version.
17 */
18
19#include <linux/config.h>
20#include <linux/errno.h>
21#include <linux/sched.h>
22#include <linux/kernel.h>
23#include <linux/mm.h>
24#include <linux/smp.h>
25#include <linux/smp_lock.h>
26#include <linux/stddef.h>
27#include <linux/unistd.h>
28#include <linux/ptrace.h>
29#include <linux/slab.h>
30#include <linux/user.h>
31#include <linux/elf.h>
32#include <linux/init.h>
33#include <linux/prctl.h>
34#include <linux/init_task.h>
35#include <linux/module.h>
36#include <linux/kallsyms.h>
37#include <linux/mqueue.h>
38#include <linux/hardirq.h>
06d67d54
PM		 39#include <linux/utsname.h>
40#include <linux/kprobes.h>
14cf11af
PM		 41
42#include <asm/pgtable.h>
43#include <asm/uaccess.h>
44#include <asm/system.h>
45#include <asm/io.h>
46#include <asm/processor.h>
47#include <asm/mmu.h>
48#include <asm/prom.h>
76032de8 49#include <asm/machdep.h>
06d67d54
PM		 50#ifdef CONFIG_PPC64
51#include <asm/firmware.h>
06d67d54
PM		 52#include <asm/time.h>
53#endif
14cf11af
PM		 54
55extern unsigned long _get_SP(void);
56
57#ifndef CONFIG_SMP
58struct task_struct *last_task_used_math = NULL;
59struct task_struct *last_task_used_altivec = NULL;
60struct task_struct *last_task_used_spe = NULL;
61#endif
62
14cf11af
PM		 63/*
64 * Make sure the floating-point register state in the
65 * the thread_struct is up to date for task tsk.
66 */
67void flush_fp_to_thread(struct task_struct *tsk)
68{
69 if (tsk->thread.regs) {
70 /*
71 * We need to disable preemption here because if we didn't,
72 * another process could get scheduled after the regs->msr
73 * test but before we have finished saving the FP registers
74 * to the thread_struct. That process could take over the
75 * FPU, and then when we get scheduled again we would store
76 * bogus values for the remaining FP registers.
77 */
78 preempt_disable();
79 if (tsk->thread.regs->msr & MSR_FP) {
80#ifdef CONFIG_SMP
81 /*
82 * This should only ever be called for current or
83 * for a stopped child process. Since we save away
84 * the FP register state on context switch on SMP,
85 * there is something wrong if a stopped child appears
86 * to still have its FP state in the CPU registers.
87 */
88 BUG_ON(tsk != current);
89#endif
90 giveup_fpu(current);
91 }
92 preempt_enable();
93 }
94}
95
96void enable_kernel_fp(void)
97{
98 WARN_ON(preemptible());
99
100#ifdef CONFIG_SMP
101 if (current->thread.regs && (current->thread.regs->msr & MSR_FP))
102 giveup_fpu(current);
103 else
104 giveup_fpu(NULL); /* just enables FP for kernel */
105#else
106 giveup_fpu(last_task_used_math);
107#endif /* CONFIG_SMP */
108}
109EXPORT_SYMBOL(enable_kernel_fp);
110
111int dump_task_fpu(struct task_struct *tsk, elf_fpregset_t *fpregs)
112{
113 if (!tsk->thread.regs)
114 return 0;
115 flush_fp_to_thread(current);
116
117 memcpy(fpregs, &tsk->thread.fpr[0], sizeof(*fpregs));
118
119 return 1;
120}
121
122#ifdef CONFIG_ALTIVEC
123void enable_kernel_altivec(void)
124{
125 WARN_ON(preemptible());
126
127#ifdef CONFIG_SMP
128 if (current->thread.regs && (current->thread.regs->msr & MSR_VEC))
129 giveup_altivec(current);
130 else
131 giveup_altivec(NULL); /* just enable AltiVec for kernel - force */
132#else
133 giveup_altivec(last_task_used_altivec);
134#endif /* CONFIG_SMP */
135}
136EXPORT_SYMBOL(enable_kernel_altivec);
137
138/*
139 * Make sure the VMX/Altivec register state in the
140 * the thread_struct is up to date for task tsk.
141 */
142void flush_altivec_to_thread(struct task_struct *tsk)
143{
144 if (tsk->thread.regs) {
145 preempt_disable();
146 if (tsk->thread.regs->msr & MSR_VEC) {
147#ifdef CONFIG_SMP
148 BUG_ON(tsk != current);
149#endif
150 giveup_altivec(current);
151 }
152 preempt_enable();
153 }
154}
155
156int dump_task_altivec(struct pt_regs *regs, elf_vrregset_t *vrregs)
157{
158 flush_altivec_to_thread(current);
159 memcpy(vrregs, &current->thread.vr[0], sizeof(*vrregs));
160 return 1;
161}
162#endif /* CONFIG_ALTIVEC */
163
164#ifdef CONFIG_SPE
165
166void enable_kernel_spe(void)
167{
168 WARN_ON(preemptible());
169
170#ifdef CONFIG_SMP
171 if (current->thread.regs && (current->thread.regs->msr & MSR_SPE))
172 giveup_spe(current);
173 else
174 giveup_spe(NULL); /* just enable SPE for kernel - force */
175#else
176 giveup_spe(last_task_used_spe);
177#endif /* __SMP __ */
178}
179EXPORT_SYMBOL(enable_kernel_spe);
180
181void flush_spe_to_thread(struct task_struct *tsk)
182{
183 if (tsk->thread.regs) {
184 preempt_disable();
185 if (tsk->thread.regs->msr & MSR_SPE) {
186#ifdef CONFIG_SMP
187 BUG_ON(tsk != current);
188#endif
189 giveup_spe(current);
190 }
191 preempt_enable();
192 }
193}
194
195int dump_spe(struct pt_regs *regs, elf_vrregset_t *evrregs)
196{
197 flush_spe_to_thread(current);
198 /* We copy u32 evr[32] + u64 acc + u32 spefscr -> 35 */
199 memcpy(evrregs, &current->thread.evr[0], sizeof(u32) * 35);
200 return 1;
201}
202#endif /* CONFIG_SPE */
203
48abec07
PM		 204/*
205 * If we are doing lazy switching of CPU state (FP, altivec or SPE),
206 * and the current task has some state, discard it.
207 */
208static inline void discard_lazy_cpu_state(void)
209{
210#ifndef CONFIG_SMP
211 preempt_disable();
212 if (last_task_used_math == current)
213 last_task_used_math = NULL;
214#ifdef CONFIG_ALTIVEC
215 if (last_task_used_altivec == current)
216 last_task_used_altivec = NULL;
217#endif /* CONFIG_ALTIVEC */
218#ifdef CONFIG_SPE
219 if (last_task_used_spe == current)
220 last_task_used_spe = NULL;
221#endif
222 preempt_enable();
223#endif /* CONFIG_SMP */
224}
225
14cf11af
PM		 226int set_dabr(unsigned long dabr)
227{
cab0af98
ME		 228 if (ppc_md.set_dabr)
229 return ppc_md.set_dabr(dabr);
14cf11af 230
cab0af98
ME		 231 mtspr(SPRN_DABR, dabr);
232 return 0;
14cf11af
PM		 233}
234
06d67d54
PM		 235#ifdef CONFIG_PPC64
236DEFINE_PER_CPU(struct cpu_usage, cpu_usage_array);
14cf11af 237static DEFINE_PER_CPU(unsigned long, current_dabr);
06d67d54 238#endif
14cf11af
PM		 239
240struct task_struct *__switch_to(struct task_struct *prev,
241 struct task_struct *new)
242{
243 struct thread_struct *new_thread, *old_thread;
244 unsigned long flags;
245 struct task_struct *last;
246
247#ifdef CONFIG_SMP
248 /* avoid complexity of lazy save/restore of fpu
249 * by just saving it every time we switch out if
250 * this task used the fpu during the last quantum.
251 *
252 * If it tries to use the fpu again, it'll trap and
253 * reload its fp regs. So we don't have to do a restore
254 * every switch, just a save.
255 * -- Cort
256 */
257 if (prev->thread.regs && (prev->thread.regs->msr & MSR_FP))
258 giveup_fpu(prev);
259#ifdef CONFIG_ALTIVEC
260 /*
261 * If the previous thread used altivec in the last quantum
262 * (thus changing altivec regs) then save them.
263 * We used to check the VRSAVE register but not all apps
264 * set it, so we don't rely on it now (and in fact we need
265 * to save & restore VSCR even if VRSAVE == 0). -- paulus
266 *
267 * On SMP we always save/restore altivec regs just to avoid the
268 * complexity of changing processors.
269 * -- Cort
270 */
271 if (prev->thread.regs && (prev->thread.regs->msr & MSR_VEC))
272 giveup_altivec(prev);
14cf11af
PM		 273#endif /* CONFIG_ALTIVEC */
274#ifdef CONFIG_SPE
275 /*
276 * If the previous thread used spe in the last quantum
277 * (thus changing spe regs) then save them.
278 *
279 * On SMP we always save/restore spe regs just to avoid the
280 * complexity of changing processors.
281 */
282 if ((prev->thread.regs && (prev->thread.regs->msr & MSR_SPE)))
283 giveup_spe(prev);
c0c0d996
PM		 284#endif /* CONFIG_SPE */
285
286#else /* CONFIG_SMP */
287#ifdef CONFIG_ALTIVEC
288 /* Avoid the trap. On smp this this never happens since
289 * we don't set last_task_used_altivec -- Cort
290 */
291 if (new->thread.regs && last_task_used_altivec == new)
292 new->thread.regs->msr |= MSR_VEC;
293#endif /* CONFIG_ALTIVEC */
294#ifdef CONFIG_SPE
14cf11af
PM		 295 /* Avoid the trap. On smp this this never happens since
296 * we don't set last_task_used_spe
297 */
298 if (new->thread.regs && last_task_used_spe == new)
299 new->thread.regs->msr |= MSR_SPE;
300#endif /* CONFIG_SPE */
c0c0d996 301
14cf11af
PM		 302#endif /* CONFIG_SMP */
303
304#ifdef CONFIG_PPC64 /* for now */
305 if (unlikely(__get_cpu_var(current_dabr) != new->thread.dabr)) {
306 set_dabr(new->thread.dabr);
307 __get_cpu_var(current_dabr) = new->thread.dabr;
308 }
06d67d54
PM		 309
310 flush_tlb_pending();
14cf11af
PM		 311#endif
312
313 new_thread = &new->thread;
314 old_thread = &current->thread;
06d67d54
PM		 315
316#ifdef CONFIG_PPC64
317 /*
318 * Collect processor utilization data per process
319 */
320 if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
321 struct cpu_usage *cu = &__get_cpu_var(cpu_usage_array);
322 long unsigned start_tb, current_tb;
323 start_tb = old_thread->start_tb;
324 cu->current_tb = current_tb = mfspr(SPRN_PURR);
325 old_thread->accum_tb += (current_tb - start_tb);
326 new_thread->start_tb = current_tb;
327 }
328#endif
329
14cf11af
PM		 330 local_irq_save(flags);
331 last = _switch(old_thread, new_thread);
332
333 local_irq_restore(flags);
334
335 return last;
336}
337
06d67d54
PM		 338static int instructions_to_print = 16;
339
340#ifdef CONFIG_PPC64
341#define BAD_PC(pc) ((REGION_ID(pc) != KERNEL_REGION_ID) && \
342 (REGION_ID(pc) != VMALLOC_REGION_ID))
343#else
344#define BAD_PC(pc) ((pc) < KERNELBASE)
345#endif
346
347static void show_instructions(struct pt_regs *regs)
348{
349 int i;
350 unsigned long pc = regs->nip - (instructions_to_print * 3 / 4 *
351 sizeof(int));
352
353 printk("Instruction dump:");
354
355 for (i = 0; i < instructions_to_print; i++) {
356 int instr;
357
358 if (!(i % 8))
359 printk("\n");
360
361 if (BAD_PC(pc) || __get_user(instr, (unsigned int *)pc)) {
362 printk("XXXXXXXX ");
363 } else {
364 if (regs->nip == pc)
365 printk("<%08x> ", instr);
366 else
367 printk("%08x ", instr);
368 }
369
370 pc += sizeof(int);
371 }
372
373 printk("\n");
374}
375
376static struct regbit {
377 unsigned long bit;
378 const char *name;
379} msr_bits[] = {
380 {MSR_EE, "EE"},
381 {MSR_PR, "PR"},
382 {MSR_FP, "FP"},
383 {MSR_ME, "ME"},
384 {MSR_IR, "IR"},
385 {MSR_DR, "DR"},
386 {0, NULL}
387};
388
389static void printbits(unsigned long val, struct regbit *bits)
390{
391 const char *sep = "";
392
393 printk("<");
394 for (; bits->bit; ++bits)
395 if (val & bits->bit) {
396 printk("%s%s", sep, bits->name);
397 sep = ",";
398 }
399 printk(">");
400}
401
402#ifdef CONFIG_PPC64
403#define REG "%016lX"
404#define REGS_PER_LINE 4
405#define LAST_VOLATILE 13
406#else
407#define REG "%08lX"
408#define REGS_PER_LINE 8
409#define LAST_VOLATILE 12
410#endif
411
14cf11af
PM		 412void show_regs(struct pt_regs * regs)
413{
414 int i, trap;
415
06d67d54
PM		 416 printk("NIP: "REG" LR: "REG" CTR: "REG"\n",
417 regs->nip, regs->link, regs->ctr);
418 printk("REGS: %p TRAP: %04lx %s (%s)\n",
419 regs, regs->trap, print_tainted(), system_utsname.release);
420 printk("MSR: "REG" ", regs->msr);
421 printbits(regs->msr, msr_bits);
422 printk(" CR: %08lX XER: %08lX\n", regs->ccr, regs->xer);
14cf11af
PM		 423 trap = TRAP(regs);
424 if (trap == 0x300 || trap == 0x600)
06d67d54
PM		 425 printk("DAR: "REG", DSISR: "REG"\n", regs->dar, regs->dsisr);
426 printk("TASK = %p[%d] '%s' THREAD: %p",
14cf11af 427 current, current->pid, current->comm, current->thread_info);
14cf11af
PM		 428
429#ifdef CONFIG_SMP
430 printk(" CPU: %d", smp_processor_id());
431#endif /* CONFIG_SMP */
432
433 for (i = 0; i < 32; i++) {
06d67d54 434 if ((i % REGS_PER_LINE) == 0)
14cf11af 435 printk("\n" KERN_INFO "GPR%02d: ", i);
06d67d54
PM		 436 printk(REG " ", regs->gpr[i]);
437 if (i == LAST_VOLATILE && !FULL_REGS(regs))
14cf11af
PM		 438 break;
439 }
440 printk("\n");
441#ifdef CONFIG_KALLSYMS
442 /*
443 * Lookup NIP late so we have the best change of getting the
444 * above info out without failing
445 */
06d67d54 446 printk("NIP ["REG"] ", regs->nip);
14cf11af 447 print_symbol("%s\n", regs->nip);
06d67d54 448 printk("LR ["REG"] ", regs->link);
14cf11af
PM		 449 print_symbol("%s\n", regs->link);
450#endif
451 show_stack(current, (unsigned long *) regs->gpr[1]);
06d67d54
PM		 452 if (!user_mode(regs))
453 show_instructions(regs);
14cf11af
PM		 454}
455
456void exit_thread(void)
457{
06d67d54 458 kprobe_flush_task(current);
48abec07 459 discard_lazy_cpu_state();
14cf11af
PM		 460}
461
462void flush_thread(void)
463{
06d67d54
PM		 464#ifdef CONFIG_PPC64
465 struct thread_info *t = current_thread_info();
466
467 if (t->flags & _TIF_ABI_PENDING)
468 t->flags ^= (_TIF_ABI_PENDING | _TIF_32BIT);
469#endif
06d67d54 470
48abec07 471 discard_lazy_cpu_state();
14cf11af
PM		 472
473#ifdef CONFIG_PPC64 /* for now */
474 if (current->thread.dabr) {
475 current->thread.dabr = 0;
476 set_dabr(0);
477 }
478#endif
479}
480
481void
482release_thread(struct task_struct *t)
483{
484}
485
486/*
487 * This gets called before we allocate a new thread and copy
488 * the current task into it.
489 */
490void prepare_to_copy(struct task_struct *tsk)
491{
492 flush_fp_to_thread(current);
493 flush_altivec_to_thread(current);
494 flush_spe_to_thread(current);
495}
496
497/*
498 * Copy a thread..
499 */
06d67d54
PM		 500int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
501 unsigned long unused, struct task_struct *p,
502 struct pt_regs *regs)
14cf11af
PM		 503{
504 struct pt_regs *childregs, *kregs;
505 extern void ret_from_fork(void);
506 unsigned long sp = (unsigned long)p->thread_info + THREAD_SIZE;
14cf11af
PM		 507
508 CHECK_FULL_REGS(regs);
509 /* Copy registers */
510 sp -= sizeof(struct pt_regs);
511 childregs = (struct pt_regs *) sp;
512 *childregs = *regs;
513 if ((childregs->msr & MSR_PR) == 0) {
514 /* for kernel thread, set `current' and stackptr in new task */
515 childregs->gpr[1] = sp + sizeof(struct pt_regs);
06d67d54 516#ifdef CONFIG_PPC32
14cf11af 517 childregs->gpr[2] = (unsigned long) p;
06d67d54
PM		 518#else
519 clear_ti_thread_flag(p->thread_info, TIF_32BIT);
520#endif
14cf11af
PM		 521 p->thread.regs = NULL; /* no user register state */
522 } else {
523 childregs->gpr[1] = usp;
524 p->thread.regs = childregs;
06d67d54
PM		 525 if (clone_flags & CLONE_SETTLS) {
526#ifdef CONFIG_PPC64
527 if (!test_thread_flag(TIF_32BIT))
528 childregs->gpr[13] = childregs->gpr[6];
529 else
530#endif
531 childregs->gpr[2] = childregs->gpr[6];
532 }
14cf11af
PM		 533 }
534 childregs->gpr[3] = 0; /* Result from fork() */
535 sp -= STACK_FRAME_OVERHEAD;
14cf11af
PM		 536
537 /*
538 * The way this works is that at some point in the future
539 * some task will call _switch to switch to the new task.
540 * That will pop off the stack frame created below and start
541 * the new task running at ret_from_fork. The new task will
542 * do some house keeping and then return from the fork or clone
543 * system call, using the stack frame created above.
544 */
545 sp -= sizeof(struct pt_regs);
546 kregs = (struct pt_regs *) sp;
547 sp -= STACK_FRAME_OVERHEAD;
548 p->thread.ksp = sp;
14cf11af 549
06d67d54
PM		 550#ifdef CONFIG_PPC64
551 if (cpu_has_feature(CPU_FTR_SLB)) {
552 unsigned long sp_vsid = get_kernel_vsid(sp);
3c726f8d 553 unsigned long llp = mmu_psize_defs[mmu_linear_psize].sllp;
06d67d54
PM		 554
555 sp_vsid <<= SLB_VSID_SHIFT;
3c726f8d 556 sp_vsid |= SLB_VSID_KERNEL | llp;
06d67d54
PM		 557 p->thread.ksp_vsid = sp_vsid;
558 }
559
560 /*
561 * The PPC64 ABI makes use of a TOC to contain function
562 * pointers. The function (ret_from_except) is actually a pointer
563 * to the TOC entry. The first entry is a pointer to the actual
564 * function.
565 */
566 kregs->nip = *((unsigned long *)ret_from_fork);
567#else
568 kregs->nip = (unsigned long)ret_from_fork;
14cf11af 569 p->thread.last_syscall = -1;
06d67d54 570#endif
14cf11af
PM		 571
572 return 0;
573}
574
575/*
576 * Set up a thread for executing a new program
577 */
06d67d54 578void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp)
14cf11af 579{
90eac727
ME		 580#ifdef CONFIG_PPC64
581 unsigned long load_addr = regs->gpr[2]; /* saved by ELF_PLAT_INIT */
582#endif
583
14cf11af 584 set_fs(USER_DS);
06d67d54
PM		 585
586 /*
587 * If we exec out of a kernel thread then thread.regs will not be
588 * set. Do it now.
589 */
590 if (!current->thread.regs) {
591 unsigned long childregs = (unsigned long)current->thread_info +
592 THREAD_SIZE;
593 childregs -= sizeof(struct pt_regs);
594 current->thread.regs = (struct pt_regs *)childregs;
595 }
596
14cf11af
PM		 597 memset(regs->gpr, 0, sizeof(regs->gpr));
598 regs->ctr = 0;
599 regs->link = 0;
600 regs->xer = 0;
601 regs->ccr = 0;
14cf11af 602 regs->gpr[1] = sp;
06d67d54
PM		 603
604#ifdef CONFIG_PPC32
605 regs->mq = 0;
606 regs->nip = start;
14cf11af 607 regs->msr = MSR_USER;
06d67d54 608#else
d4bf9a78 609 if (!test_thread_flag(TIF_32BIT)) {
90eac727 610 unsigned long entry, toc;
06d67d54
PM		 611
612 /* start is a relocated pointer to the function descriptor for
613 * the elf _start routine. The first entry in the function
614 * descriptor is the entry address of _start and the second
615 * entry is the TOC value we need to use.
616 */
617 __get_user(entry, (unsigned long __user *)start);
618 __get_user(toc, (unsigned long __user *)start+1);
619
620 /* Check whether the e_entry function descriptor entries
621 * need to be relocated before we can use them.
622 */
623 if (load_addr != 0) {
624 entry += load_addr;
625 toc += load_addr;
626 }
627 regs->nip = entry;
628 regs->gpr[2] = toc;
629 regs->msr = MSR_USER64;
d4bf9a78
SR		 630 } else {
631 regs->nip = start;
632 regs->gpr[2] = 0;
633 regs->msr = MSR_USER32;
06d67d54
PM		 634 }
635#endif
636
48abec07 637 discard_lazy_cpu_state();
14cf11af 638 memset(current->thread.fpr, 0, sizeof(current->thread.fpr));
25c8a78b 639 current->thread.fpscr.val = 0;
14cf11af
PM		 640#ifdef CONFIG_ALTIVEC
641 memset(current->thread.vr, 0, sizeof(current->thread.vr));
642 memset(&current->thread.vscr, 0, sizeof(current->thread.vscr));
06d67d54 643 current->thread.vscr.u[3] = 0x00010000; /* Java mode disabled */
14cf11af
PM		 644 current->thread.vrsave = 0;
645 current->thread.used_vr = 0;
646#endif /* CONFIG_ALTIVEC */
647#ifdef CONFIG_SPE
648 memset(current->thread.evr, 0, sizeof(current->thread.evr));
649 current->thread.acc = 0;
650 current->thread.spefscr = 0;
651 current->thread.used_spe = 0;
652#endif /* CONFIG_SPE */
653}
654
655#define PR_FP_ALL_EXCEPT (PR_FP_EXC_DIV | PR_FP_EXC_OVF | PR_FP_EXC_UND \
656 | PR_FP_EXC_RES | PR_FP_EXC_INV)
657
658int set_fpexc_mode(struct task_struct *tsk, unsigned int val)
659{
660 struct pt_regs *regs = tsk->thread.regs;
661
662 /* This is a bit hairy. If we are an SPE enabled processor
663 * (have embedded fp) we store the IEEE exception enable flags in
664 * fpexc_mode. fpexc_mode is also used for setting FP exception
665 * mode (asyn, precise, disabled) for 'Classic' FP. */
666 if (val & PR_FP_EXC_SW_ENABLE) {
667#ifdef CONFIG_SPE
668 tsk->thread.fpexc_mode = val &
669 (PR_FP_EXC_SW_ENABLE | PR_FP_ALL_EXCEPT);
06d67d54 670 return 0;
14cf11af
PM		 671#else
672 return -EINVAL;
673#endif
14cf11af 674 }
06d67d54
PM		 675
676 /* on a CONFIG_SPE this does not hurt us. The bits that
677 * __pack_fe01 use do not overlap with bits used for
678 * PR_FP_EXC_SW_ENABLE. Additionally, the MSR[FE0,FE1] bits
679 * on CONFIG_SPE implementations are reserved so writing to
680 * them does not change anything */
681 if (val > PR_FP_EXC_PRECISE)
682 return -EINVAL;
683 tsk->thread.fpexc_mode = __pack_fe01(val);
684 if (regs != NULL && (regs->msr & MSR_FP) != 0)
685 regs->msr = (regs->msr & ~(MSR_FE0|MSR_FE1))
686 | tsk->thread.fpexc_mode;
14cf11af
PM		 687 return 0;
688}
689
690int get_fpexc_mode(struct task_struct *tsk, unsigned long adr)
691{
692 unsigned int val;
693
694 if (tsk->thread.fpexc_mode & PR_FP_EXC_SW_ENABLE)
695#ifdef CONFIG_SPE
696 val = tsk->thread.fpexc_mode;
697#else
698 return -EINVAL;
699#endif
700 else
701 val = __unpack_fe01(tsk->thread.fpexc_mode);
702 return put_user(val, (unsigned int __user *) adr);
703}
704
06d67d54
PM		 705#define TRUNC_PTR(x) ((typeof(x))(((unsigned long)(x)) & 0xffffffff))
706
14cf11af
PM		 707int sys_clone(unsigned long clone_flags, unsigned long usp,
708 int __user *parent_tidp, void __user *child_threadptr,
709 int __user *child_tidp, int p6,
710 struct pt_regs *regs)
711{
712 CHECK_FULL_REGS(regs);
713 if (usp == 0)
714 usp = regs->gpr[1]; /* stack pointer for child */
06d67d54
PM		 715#ifdef CONFIG_PPC64
716 if (test_thread_flag(TIF_32BIT)) {
717 parent_tidp = TRUNC_PTR(parent_tidp);
718 child_tidp = TRUNC_PTR(child_tidp);
719 }
720#endif
14cf11af
PM		 721 return do_fork(clone_flags, usp, regs, 0, parent_tidp, child_tidp);
722}
723
724int sys_fork(unsigned long p1, unsigned long p2, unsigned long p3,
725 unsigned long p4, unsigned long p5, unsigned long p6,
726 struct pt_regs *regs)
727{
728 CHECK_FULL_REGS(regs);
729 return do_fork(SIGCHLD, regs->gpr[1], regs, 0, NULL, NULL);
730}
731
732int sys_vfork(unsigned long p1, unsigned long p2, unsigned long p3,
733 unsigned long p4, unsigned long p5, unsigned long p6,
734 struct pt_regs *regs)
735{
736 CHECK_FULL_REGS(regs);
737 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->gpr[1],
738 regs, 0, NULL, NULL);
739}
740
741int sys_execve(unsigned long a0, unsigned long a1, unsigned long a2,
742 unsigned long a3, unsigned long a4, unsigned long a5,
743 struct pt_regs *regs)
744{
745 int error;
06d67d54 746 char *filename;
14cf11af
PM		 747
748 filename = getname((char __user *) a0);
749 error = PTR_ERR(filename);
750 if (IS_ERR(filename))
751 goto out;
752 flush_fp_to_thread(current);
753 flush_altivec_to_thread(current);
754 flush_spe_to_thread(current);
20c8c210
PM		 755 error = do_execve(filename, (char __user * __user *) a1,
756 (char __user * __user *) a2, regs);
14cf11af
PM		 757 if (error == 0) {
758 task_lock(current);
759 current->ptrace &= ~PT_DTRACE;
760 task_unlock(current);
761 }
762 putname(filename);
763out:
764 return error;
765}
766
767static int validate_sp(unsigned long sp, struct task_struct *p,
768 unsigned long nbytes)
769{
770 unsigned long stack_page = (unsigned long)p->thread_info;
771
772 if (sp >= stack_page + sizeof(struct thread_struct)
773 && sp <= stack_page + THREAD_SIZE - nbytes)
774 return 1;
775
776#ifdef CONFIG_IRQSTACKS
777 stack_page = (unsigned long) hardirq_ctx[task_cpu(p)];
778 if (sp >= stack_page + sizeof(struct thread_struct)
779 && sp <= stack_page + THREAD_SIZE - nbytes)
780 return 1;
781
782 stack_page = (unsigned long) softirq_ctx[task_cpu(p)];
783 if (sp >= stack_page + sizeof(struct thread_struct)
784 && sp <= stack_page + THREAD_SIZE - nbytes)
785 return 1;
786#endif
787
788 return 0;
789}
790
06d67d54
PM		 791#ifdef CONFIG_PPC64
792#define MIN_STACK_FRAME 112 /* same as STACK_FRAME_OVERHEAD, in fact */
793#define FRAME_LR_SAVE 2
794#define INT_FRAME_SIZE (sizeof(struct pt_regs) + STACK_FRAME_OVERHEAD + 288)
795#define REGS_MARKER 0x7265677368657265ul
796#define FRAME_MARKER 12
797#else
798#define MIN_STACK_FRAME 16
799#define FRAME_LR_SAVE 1
800#define INT_FRAME_SIZE (sizeof(struct pt_regs) + STACK_FRAME_OVERHEAD)
801#define REGS_MARKER 0x72656773ul
802#define FRAME_MARKER 2
14cf11af 803#endif
14cf11af
PM		 804
805unsigned long get_wchan(struct task_struct *p)
806{
807 unsigned long ip, sp;
808 int count = 0;
809
810 if (!p || p == current || p->state == TASK_RUNNING)
811 return 0;
812
813 sp = p->thread.ksp;
06d67d54 814 if (!validate_sp(sp, p, MIN_STACK_FRAME))
14cf11af
PM		 815 return 0;
816
817 do {
818 sp = *(unsigned long *)sp;
06d67d54 819 if (!validate_sp(sp, p, MIN_STACK_FRAME))
14cf11af
PM		 820 return 0;
821 if (count > 0) {
06d67d54 822 ip = ((unsigned long *)sp)[FRAME_LR_SAVE];
14cf11af
PM		 823 if (!in_sched_functions(ip))
824 return ip;
825 }
826 } while (count++ < 16);
827 return 0;
828}
829EXPORT_SYMBOL(get_wchan);
06d67d54
PM		 830
831static int kstack_depth_to_print = 64;
832
833void show_stack(struct task_struct *tsk, unsigned long *stack)
834{
835 unsigned long sp, ip, lr, newsp;
836 int count = 0;
837 int firstframe = 1;
838
839 sp = (unsigned long) stack;
840 if (tsk == NULL)
841 tsk = current;
842 if (sp == 0) {
843 if (tsk == current)
844 asm("mr %0,1" : "=r" (sp));
845 else
846 sp = tsk->thread.ksp;
847 }
848
849 lr = 0;
850 printk("Call Trace:\n");
851 do {
852 if (!validate_sp(sp, tsk, MIN_STACK_FRAME))
853 return;
854
855 stack = (unsigned long *) sp;
856 newsp = stack[0];
857 ip = stack[FRAME_LR_SAVE];
858 if (!firstframe || ip != lr) {
859 printk("["REG"] ["REG"] ", sp, ip);
860 print_symbol("%s", ip);
861 if (firstframe)
862 printk(" (unreliable)");
863 printk("\n");
864 }
865 firstframe = 0;
866
867 /*
868 * See if this is an exception frame.
869 * We look for the "regshere" marker in the current frame.
870 */
871 if (validate_sp(sp, tsk, INT_FRAME_SIZE)
872 && stack[FRAME_MARKER] == REGS_MARKER) {
873 struct pt_regs *regs = (struct pt_regs *)
874 (sp + STACK_FRAME_OVERHEAD);
875 printk("--- Exception: %lx", regs->trap);
876 print_symbol(" at %s\n", regs->nip);
877 lr = regs->link;
878 print_symbol(" LR = %s\n", lr);
879 firstframe = 1;
880 }
881
882 sp = newsp;
883 } while (count++ < kstack_depth_to_print);
884}
885
886void dump_stack(void)
887{
888 show_stack(current, NULL);
889}
890EXPORT_SYMBOL(dump_stack);
kernel source for telekom puls (alcatel/mediatek)