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powerpc: Various UP build fixes
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / powerpc / kernel / process.c
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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>
06d67d54
PM		 49#ifdef CONFIG_PPC64
50#include <asm/firmware.h>
06d67d54 51#include <asm/time.h>
cab0af98 52#include <asm/machdep.h>
06d67d54 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
14cf11af
PM		 204int set_dabr(unsigned long dabr)
205{
14cf11af 206#ifdef CONFIG_PPC64
cab0af98
ME		 207 if (ppc_md.set_dabr)
208 return ppc_md.set_dabr(dabr);
14cf11af 209#endif
14cf11af 210
cab0af98
ME		 211 mtspr(SPRN_DABR, dabr);
212 return 0;
14cf11af
PM		 213}
214
06d67d54
PM		 215#ifdef CONFIG_PPC64
216DEFINE_PER_CPU(struct cpu_usage, cpu_usage_array);
14cf11af 217static DEFINE_PER_CPU(unsigned long, current_dabr);
06d67d54 218#endif
14cf11af
PM		 219
220struct task_struct *__switch_to(struct task_struct *prev,
221 struct task_struct *new)
222{
223 struct thread_struct *new_thread, *old_thread;
224 unsigned long flags;
225 struct task_struct *last;
226
227#ifdef CONFIG_SMP
228 /* avoid complexity of lazy save/restore of fpu
229 * by just saving it every time we switch out if
230 * this task used the fpu during the last quantum.
231 *
232 * If it tries to use the fpu again, it'll trap and
233 * reload its fp regs. So we don't have to do a restore
234 * every switch, just a save.
235 * -- Cort
236 */
237 if (prev->thread.regs && (prev->thread.regs->msr & MSR_FP))
238 giveup_fpu(prev);
239#ifdef CONFIG_ALTIVEC
240 /*
241 * If the previous thread used altivec in the last quantum
242 * (thus changing altivec regs) then save them.
243 * We used to check the VRSAVE register but not all apps
244 * set it, so we don't rely on it now (and in fact we need
245 * to save & restore VSCR even if VRSAVE == 0). -- paulus
246 *
247 * On SMP we always save/restore altivec regs just to avoid the
248 * complexity of changing processors.
249 * -- Cort
250 */
251 if (prev->thread.regs && (prev->thread.regs->msr & MSR_VEC))
252 giveup_altivec(prev);
14cf11af
PM		 253#endif /* CONFIG_ALTIVEC */
254#ifdef CONFIG_SPE
255 /*
256 * If the previous thread used spe in the last quantum
257 * (thus changing spe regs) then save them.
258 *
259 * On SMP we always save/restore spe regs just to avoid the
260 * complexity of changing processors.
261 */
262 if ((prev->thread.regs && (prev->thread.regs->msr & MSR_SPE)))
263 giveup_spe(prev);
c0c0d996
PM		 264#endif /* CONFIG_SPE */
265
266#else /* CONFIG_SMP */
267#ifdef CONFIG_ALTIVEC
268 /* Avoid the trap. On smp this this never happens since
269 * we don't set last_task_used_altivec -- Cort
270 */
271 if (new->thread.regs && last_task_used_altivec == new)
272 new->thread.regs->msr |= MSR_VEC;
273#endif /* CONFIG_ALTIVEC */
274#ifdef CONFIG_SPE
14cf11af
PM		 275 /* Avoid the trap. On smp this this never happens since
276 * we don't set last_task_used_spe
277 */
278 if (new->thread.regs && last_task_used_spe == new)
279 new->thread.regs->msr |= MSR_SPE;
280#endif /* CONFIG_SPE */
c0c0d996 281
14cf11af
PM		 282#endif /* CONFIG_SMP */
283
284#ifdef CONFIG_PPC64 /* for now */
285 if (unlikely(__get_cpu_var(current_dabr) != new->thread.dabr)) {
286 set_dabr(new->thread.dabr);
287 __get_cpu_var(current_dabr) = new->thread.dabr;
288 }
06d67d54
PM		 289
290 flush_tlb_pending();
14cf11af
PM		 291#endif
292
293 new_thread = &new->thread;
294 old_thread = &current->thread;
06d67d54
PM		 295
296#ifdef CONFIG_PPC64
297 /*
298 * Collect processor utilization data per process
299 */
300 if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
301 struct cpu_usage *cu = &__get_cpu_var(cpu_usage_array);
302 long unsigned start_tb, current_tb;
303 start_tb = old_thread->start_tb;
304 cu->current_tb = current_tb = mfspr(SPRN_PURR);
305 old_thread->accum_tb += (current_tb - start_tb);
306 new_thread->start_tb = current_tb;
307 }
308#endif
309
14cf11af
PM		 310 local_irq_save(flags);
311 last = _switch(old_thread, new_thread);
312
313 local_irq_restore(flags);
314
315 return last;
316}
317
06d67d54
PM		 318static int instructions_to_print = 16;
319
320#ifdef CONFIG_PPC64
321#define BAD_PC(pc) ((REGION_ID(pc) != KERNEL_REGION_ID) && \
322 (REGION_ID(pc) != VMALLOC_REGION_ID))
323#else
324#define BAD_PC(pc) ((pc) < KERNELBASE)
325#endif
326
327static void show_instructions(struct pt_regs *regs)
328{
329 int i;
330 unsigned long pc = regs->nip - (instructions_to_print * 3 / 4 *
331 sizeof(int));
332
333 printk("Instruction dump:");
334
335 for (i = 0; i < instructions_to_print; i++) {
336 int instr;
337
338 if (!(i % 8))
339 printk("\n");
340
341 if (BAD_PC(pc) || __get_user(instr, (unsigned int *)pc)) {
342 printk("XXXXXXXX ");
343 } else {
344 if (regs->nip == pc)
345 printk("<%08x> ", instr);
346 else
347 printk("%08x ", instr);
348 }
349
350 pc += sizeof(int);
351 }
352
353 printk("\n");
354}
355
356static struct regbit {
357 unsigned long bit;
358 const char *name;
359} msr_bits[] = {
360 {MSR_EE, "EE"},
361 {MSR_PR, "PR"},
362 {MSR_FP, "FP"},
363 {MSR_ME, "ME"},
364 {MSR_IR, "IR"},
365 {MSR_DR, "DR"},
366 {0, NULL}
367};
368
369static void printbits(unsigned long val, struct regbit *bits)
370{
371 const char *sep = "";
372
373 printk("<");
374 for (; bits->bit; ++bits)
375 if (val & bits->bit) {
376 printk("%s%s", sep, bits->name);
377 sep = ",";
378 }
379 printk(">");
380}
381
382#ifdef CONFIG_PPC64
383#define REG "%016lX"
384#define REGS_PER_LINE 4
385#define LAST_VOLATILE 13
386#else
387#define REG "%08lX"
388#define REGS_PER_LINE 8
389#define LAST_VOLATILE 12
390#endif
391
14cf11af
PM		 392void show_regs(struct pt_regs * regs)
393{
394 int i, trap;
395
06d67d54
PM		 396 printk("NIP: "REG" LR: "REG" CTR: "REG"\n",
397 regs->nip, regs->link, regs->ctr);
398 printk("REGS: %p TRAP: %04lx %s (%s)\n",
399 regs, regs->trap, print_tainted(), system_utsname.release);
400 printk("MSR: "REG" ", regs->msr);
401 printbits(regs->msr, msr_bits);
402 printk(" CR: %08lX XER: %08lX\n", regs->ccr, regs->xer);
14cf11af
PM		 403 trap = TRAP(regs);
404 if (trap == 0x300 || trap == 0x600)
06d67d54
PM		 405 printk("DAR: "REG", DSISR: "REG"\n", regs->dar, regs->dsisr);
406 printk("TASK = %p[%d] '%s' THREAD: %p",
14cf11af 407 current, current->pid, current->comm, current->thread_info);
14cf11af
PM		 408
409#ifdef CONFIG_SMP
410 printk(" CPU: %d", smp_processor_id());
411#endif /* CONFIG_SMP */
412
413 for (i = 0; i < 32; i++) {
06d67d54 414 if ((i % REGS_PER_LINE) == 0)
14cf11af 415 printk("\n" KERN_INFO "GPR%02d: ", i);
06d67d54
PM		 416 printk(REG " ", regs->gpr[i]);
417 if (i == LAST_VOLATILE && !FULL_REGS(regs))
14cf11af
PM		 418 break;
419 }
420 printk("\n");
421#ifdef CONFIG_KALLSYMS
422 /*
423 * Lookup NIP late so we have the best change of getting the
424 * above info out without failing
425 */
06d67d54 426 printk("NIP ["REG"] ", regs->nip);
14cf11af 427 print_symbol("%s\n", regs->nip);
06d67d54 428 printk("LR ["REG"] ", regs->link);
14cf11af
PM		 429 print_symbol("%s\n", regs->link);
430#endif
431 show_stack(current, (unsigned long *) regs->gpr[1]);
06d67d54
PM		 432 if (!user_mode(regs))
433 show_instructions(regs);
14cf11af
PM		 434}
435
436void exit_thread(void)
437{
06d67d54
PM		 438 kprobe_flush_task(current);
439
14cf11af
PM		 440#ifndef CONFIG_SMP
441 if (last_task_used_math == current)
442 last_task_used_math = NULL;
443#ifdef CONFIG_ALTIVEC
444 if (last_task_used_altivec == current)
445 last_task_used_altivec = NULL;
446#endif /* CONFIG_ALTIVEC */
447#ifdef CONFIG_SPE
448 if (last_task_used_spe == current)
449 last_task_used_spe = NULL;
450#endif
451#endif /* CONFIG_SMP */
452}
453
454void flush_thread(void)
455{
06d67d54
PM		 456#ifdef CONFIG_PPC64
457 struct thread_info *t = current_thread_info();
458
459 if (t->flags & _TIF_ABI_PENDING)
460 t->flags ^= (_TIF_ABI_PENDING | _TIF_32BIT);
461#endif
462 kprobe_flush_task(current);
463
14cf11af
PM		 464#ifndef CONFIG_SMP
465 if (last_task_used_math == current)
466 last_task_used_math = NULL;
467#ifdef CONFIG_ALTIVEC
468 if (last_task_used_altivec == current)
469 last_task_used_altivec = NULL;
470#endif /* CONFIG_ALTIVEC */
471#ifdef CONFIG_SPE
472 if (last_task_used_spe == current)
473 last_task_used_spe = NULL;
474#endif
475#endif /* CONFIG_SMP */
476
477#ifdef CONFIG_PPC64 /* for now */
478 if (current->thread.dabr) {
479 current->thread.dabr = 0;
480 set_dabr(0);
481 }
482#endif
483}
484
485void
486release_thread(struct task_struct *t)
487{
488}
489
490/*
491 * This gets called before we allocate a new thread and copy
492 * the current task into it.
493 */
494void prepare_to_copy(struct task_struct *tsk)
495{
496 flush_fp_to_thread(current);
497 flush_altivec_to_thread(current);
498 flush_spe_to_thread(current);
499}
500
501/*
502 * Copy a thread..
503 */
06d67d54
PM		 504int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
505 unsigned long unused, struct task_struct *p,
506 struct pt_regs *regs)
14cf11af
PM		 507{
508 struct pt_regs *childregs, *kregs;
509 extern void ret_from_fork(void);
510 unsigned long sp = (unsigned long)p->thread_info + THREAD_SIZE;
14cf11af
PM		 511
512 CHECK_FULL_REGS(regs);
513 /* Copy registers */
514 sp -= sizeof(struct pt_regs);
515 childregs = (struct pt_regs *) sp;
516 *childregs = *regs;
517 if ((childregs->msr & MSR_PR) == 0) {
518 /* for kernel thread, set `current' and stackptr in new task */
519 childregs->gpr[1] = sp + sizeof(struct pt_regs);
06d67d54 520#ifdef CONFIG_PPC32
14cf11af 521 childregs->gpr[2] = (unsigned long) p;
06d67d54
PM		 522#else
523 clear_ti_thread_flag(p->thread_info, TIF_32BIT);
524#endif
14cf11af
PM		 525 p->thread.regs = NULL; /* no user register state */
526 } else {
527 childregs->gpr[1] = usp;
528 p->thread.regs = childregs;
06d67d54
PM		 529 if (clone_flags & CLONE_SETTLS) {
530#ifdef CONFIG_PPC64
531 if (!test_thread_flag(TIF_32BIT))
532 childregs->gpr[13] = childregs->gpr[6];
533 else
534#endif
535 childregs->gpr[2] = childregs->gpr[6];
536 }
14cf11af
PM		 537 }
538 childregs->gpr[3] = 0; /* Result from fork() */
539 sp -= STACK_FRAME_OVERHEAD;
14cf11af
PM		 540
541 /*
542 * The way this works is that at some point in the future
543 * some task will call _switch to switch to the new task.
544 * That will pop off the stack frame created below and start
545 * the new task running at ret_from_fork. The new task will
546 * do some house keeping and then return from the fork or clone
547 * system call, using the stack frame created above.
548 */
549 sp -= sizeof(struct pt_regs);
550 kregs = (struct pt_regs *) sp;
551 sp -= STACK_FRAME_OVERHEAD;
552 p->thread.ksp = sp;
14cf11af 553
06d67d54
PM		 554#ifdef CONFIG_PPC64
555 if (cpu_has_feature(CPU_FTR_SLB)) {
556 unsigned long sp_vsid = get_kernel_vsid(sp);
557
558 sp_vsid <<= SLB_VSID_SHIFT;
559 sp_vsid |= SLB_VSID_KERNEL;
560 if (cpu_has_feature(CPU_FTR_16M_PAGE))
561 sp_vsid |= SLB_VSID_L;
562
563 p->thread.ksp_vsid = sp_vsid;
564 }
565
566 /*
567 * The PPC64 ABI makes use of a TOC to contain function
568 * pointers. The function (ret_from_except) is actually a pointer
569 * to the TOC entry. The first entry is a pointer to the actual
570 * function.
571 */
572 kregs->nip = *((unsigned long *)ret_from_fork);
573#else
574 kregs->nip = (unsigned long)ret_from_fork;
14cf11af 575 p->thread.last_syscall = -1;
06d67d54 576#endif
14cf11af
PM		 577
578 return 0;
579}
580
581/*
582 * Set up a thread for executing a new program
583 */
06d67d54 584void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp)
14cf11af 585{
90eac727
ME		 586#ifdef CONFIG_PPC64
587 unsigned long load_addr = regs->gpr[2]; /* saved by ELF_PLAT_INIT */
588#endif
589
14cf11af 590 set_fs(USER_DS);
06d67d54
PM		 591
592 /*
593 * If we exec out of a kernel thread then thread.regs will not be
594 * set. Do it now.
595 */
596 if (!current->thread.regs) {
597 unsigned long childregs = (unsigned long)current->thread_info +
598 THREAD_SIZE;
599 childregs -= sizeof(struct pt_regs);
600 current->thread.regs = (struct pt_regs *)childregs;
601 }
602
14cf11af
PM		 603 memset(regs->gpr, 0, sizeof(regs->gpr));
604 regs->ctr = 0;
605 regs->link = 0;
606 regs->xer = 0;
607 regs->ccr = 0;
14cf11af 608 regs->gpr[1] = sp;
06d67d54
PM		 609
610#ifdef CONFIG_PPC32
611 regs->mq = 0;
612 regs->nip = start;
14cf11af 613 regs->msr = MSR_USER;
06d67d54 614#else
d4bf9a78 615 if (!test_thread_flag(TIF_32BIT)) {
90eac727 616 unsigned long entry, toc;
06d67d54
PM		 617
618 /* start is a relocated pointer to the function descriptor for
619 * the elf _start routine. The first entry in the function
620 * descriptor is the entry address of _start and the second
621 * entry is the TOC value we need to use.
622 */
623 __get_user(entry, (unsigned long __user *)start);
624 __get_user(toc, (unsigned long __user *)start+1);
625
626 /* Check whether the e_entry function descriptor entries
627 * need to be relocated before we can use them.
628 */
629 if (load_addr != 0) {
630 entry += load_addr;
631 toc += load_addr;
632 }
633 regs->nip = entry;
634 regs->gpr[2] = toc;
635 regs->msr = MSR_USER64;
d4bf9a78
SR		 636 } else {
637 regs->nip = start;
638 regs->gpr[2] = 0;
639 regs->msr = MSR_USER32;
06d67d54
PM		 640 }
641#endif
642
14cf11af
PM		 643#ifndef CONFIG_SMP
644 if (last_task_used_math == current)
645 last_task_used_math = NULL;
646#ifdef CONFIG_ALTIVEC
647 if (last_task_used_altivec == current)
648 last_task_used_altivec = NULL;
649#endif
650#ifdef CONFIG_SPE
651 if (last_task_used_spe == current)
652 last_task_used_spe = NULL;
653#endif
654#endif /* CONFIG_SMP */
655 memset(current->thread.fpr, 0, sizeof(current->thread.fpr));
25c8a78b 656 current->thread.fpscr.val = 0;
14cf11af
PM		 657#ifdef CONFIG_ALTIVEC
658 memset(current->thread.vr, 0, sizeof(current->thread.vr));
659 memset(&current->thread.vscr, 0, sizeof(current->thread.vscr));
06d67d54 660 current->thread.vscr.u[3] = 0x00010000; /* Java mode disabled */
14cf11af
PM		 661 current->thread.vrsave = 0;
662 current->thread.used_vr = 0;
663#endif /* CONFIG_ALTIVEC */
664#ifdef CONFIG_SPE
665 memset(current->thread.evr, 0, sizeof(current->thread.evr));
666 current->thread.acc = 0;
667 current->thread.spefscr = 0;
668 current->thread.used_spe = 0;
669#endif /* CONFIG_SPE */
670}
671
672#define PR_FP_ALL_EXCEPT (PR_FP_EXC_DIV | PR_FP_EXC_OVF | PR_FP_EXC_UND \
673 | PR_FP_EXC_RES | PR_FP_EXC_INV)
674
675int set_fpexc_mode(struct task_struct *tsk, unsigned int val)
676{
677 struct pt_regs *regs = tsk->thread.regs;
678
679 /* This is a bit hairy. If we are an SPE enabled processor
680 * (have embedded fp) we store the IEEE exception enable flags in
681 * fpexc_mode. fpexc_mode is also used for setting FP exception
682 * mode (asyn, precise, disabled) for 'Classic' FP. */
683 if (val & PR_FP_EXC_SW_ENABLE) {
684#ifdef CONFIG_SPE
685 tsk->thread.fpexc_mode = val &
686 (PR_FP_EXC_SW_ENABLE | PR_FP_ALL_EXCEPT);
06d67d54 687 return 0;
14cf11af
PM		 688#else
689 return -EINVAL;
690#endif
14cf11af 691 }
06d67d54
PM		 692
693 /* on a CONFIG_SPE this does not hurt us. The bits that
694 * __pack_fe01 use do not overlap with bits used for
695 * PR_FP_EXC_SW_ENABLE. Additionally, the MSR[FE0,FE1] bits
696 * on CONFIG_SPE implementations are reserved so writing to
697 * them does not change anything */
698 if (val > PR_FP_EXC_PRECISE)
699 return -EINVAL;
700 tsk->thread.fpexc_mode = __pack_fe01(val);
701 if (regs != NULL && (regs->msr & MSR_FP) != 0)
702 regs->msr = (regs->msr & ~(MSR_FE0|MSR_FE1))
703 | tsk->thread.fpexc_mode;
14cf11af
PM		 704 return 0;
705}
706
707int get_fpexc_mode(struct task_struct *tsk, unsigned long adr)
708{
709 unsigned int val;
710
711 if (tsk->thread.fpexc_mode & PR_FP_EXC_SW_ENABLE)
712#ifdef CONFIG_SPE
713 val = tsk->thread.fpexc_mode;
714#else
715 return -EINVAL;
716#endif
717 else
718 val = __unpack_fe01(tsk->thread.fpexc_mode);
719 return put_user(val, (unsigned int __user *) adr);
720}
721
06d67d54
PM		 722#define TRUNC_PTR(x) ((typeof(x))(((unsigned long)(x)) & 0xffffffff))
723
14cf11af
PM		 724int sys_clone(unsigned long clone_flags, unsigned long usp,
725 int __user *parent_tidp, void __user *child_threadptr,
726 int __user *child_tidp, int p6,
727 struct pt_regs *regs)
728{
729 CHECK_FULL_REGS(regs);
730 if (usp == 0)
731 usp = regs->gpr[1]; /* stack pointer for child */
06d67d54
PM		 732#ifdef CONFIG_PPC64
733 if (test_thread_flag(TIF_32BIT)) {
734 parent_tidp = TRUNC_PTR(parent_tidp);
735 child_tidp = TRUNC_PTR(child_tidp);
736 }
737#endif
14cf11af
PM		 738 return do_fork(clone_flags, usp, regs, 0, parent_tidp, child_tidp);
739}
740
741int sys_fork(unsigned long p1, unsigned long p2, unsigned long p3,
742 unsigned long p4, unsigned long p5, unsigned long p6,
743 struct pt_regs *regs)
744{
745 CHECK_FULL_REGS(regs);
746 return do_fork(SIGCHLD, regs->gpr[1], regs, 0, NULL, NULL);
747}
748
749int sys_vfork(unsigned long p1, unsigned long p2, unsigned long p3,
750 unsigned long p4, unsigned long p5, unsigned long p6,
751 struct pt_regs *regs)
752{
753 CHECK_FULL_REGS(regs);
754 return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->gpr[1],
755 regs, 0, NULL, NULL);
756}
757
758int sys_execve(unsigned long a0, unsigned long a1, unsigned long a2,
759 unsigned long a3, unsigned long a4, unsigned long a5,
760 struct pt_regs *regs)
761{
762 int error;
06d67d54 763 char *filename;
14cf11af
PM		 764
765 filename = getname((char __user *) a0);
766 error = PTR_ERR(filename);
767 if (IS_ERR(filename))
768 goto out;
769 flush_fp_to_thread(current);
770 flush_altivec_to_thread(current);
771 flush_spe_to_thread(current);
20c8c210
PM		 772 error = do_execve(filename, (char __user * __user *) a1,
773 (char __user * __user *) a2, regs);
14cf11af
PM		 774 if (error == 0) {
775 task_lock(current);
776 current->ptrace &= ~PT_DTRACE;
777 task_unlock(current);
778 }
779 putname(filename);
780out:
781 return error;
782}
783
784static int validate_sp(unsigned long sp, struct task_struct *p,
785 unsigned long nbytes)
786{
787 unsigned long stack_page = (unsigned long)p->thread_info;
788
789 if (sp >= stack_page + sizeof(struct thread_struct)
790 && sp <= stack_page + THREAD_SIZE - nbytes)
791 return 1;
792
793#ifdef CONFIG_IRQSTACKS
794 stack_page = (unsigned long) hardirq_ctx[task_cpu(p)];
795 if (sp >= stack_page + sizeof(struct thread_struct)
796 && sp <= stack_page + THREAD_SIZE - nbytes)
797 return 1;
798
799 stack_page = (unsigned long) softirq_ctx[task_cpu(p)];
800 if (sp >= stack_page + sizeof(struct thread_struct)
801 && sp <= stack_page + THREAD_SIZE - nbytes)
802 return 1;
803#endif
804
805 return 0;
806}
807
06d67d54
PM		 808#ifdef CONFIG_PPC64
809#define MIN_STACK_FRAME 112 /* same as STACK_FRAME_OVERHEAD, in fact */
810#define FRAME_LR_SAVE 2
811#define INT_FRAME_SIZE (sizeof(struct pt_regs) + STACK_FRAME_OVERHEAD + 288)
812#define REGS_MARKER 0x7265677368657265ul
813#define FRAME_MARKER 12
814#else
815#define MIN_STACK_FRAME 16
816#define FRAME_LR_SAVE 1
817#define INT_FRAME_SIZE (sizeof(struct pt_regs) + STACK_FRAME_OVERHEAD)
818#define REGS_MARKER 0x72656773ul
819#define FRAME_MARKER 2
14cf11af 820#endif
14cf11af
PM		 821
822unsigned long get_wchan(struct task_struct *p)
823{
824 unsigned long ip, sp;
825 int count = 0;
826
827 if (!p || p == current || p->state == TASK_RUNNING)
828 return 0;
829
830 sp = p->thread.ksp;
06d67d54 831 if (!validate_sp(sp, p, MIN_STACK_FRAME))
14cf11af
PM		 832 return 0;
833
834 do {
835 sp = *(unsigned long *)sp;
06d67d54 836 if (!validate_sp(sp, p, MIN_STACK_FRAME))
14cf11af
PM		 837 return 0;
838 if (count > 0) {
06d67d54 839 ip = ((unsigned long *)sp)[FRAME_LR_SAVE];
14cf11af
PM		 840 if (!in_sched_functions(ip))
841 return ip;
842 }
843 } while (count++ < 16);
844 return 0;
845}
846EXPORT_SYMBOL(get_wchan);
06d67d54
PM		 847
848static int kstack_depth_to_print = 64;
849
850void show_stack(struct task_struct *tsk, unsigned long *stack)
851{
852 unsigned long sp, ip, lr, newsp;
853 int count = 0;
854 int firstframe = 1;
855
856 sp = (unsigned long) stack;
857 if (tsk == NULL)
858 tsk = current;
859 if (sp == 0) {
860 if (tsk == current)
861 asm("mr %0,1" : "=r" (sp));
862 else
863 sp = tsk->thread.ksp;
864 }
865
866 lr = 0;
867 printk("Call Trace:\n");
868 do {
869 if (!validate_sp(sp, tsk, MIN_STACK_FRAME))
870 return;
871
872 stack = (unsigned long *) sp;
873 newsp = stack[0];
874 ip = stack[FRAME_LR_SAVE];
875 if (!firstframe || ip != lr) {
876 printk("["REG"] ["REG"] ", sp, ip);
877 print_symbol("%s", ip);
878 if (firstframe)
879 printk(" (unreliable)");
880 printk("\n");
881 }
882 firstframe = 0;
883
884 /*
885 * See if this is an exception frame.
886 * We look for the "regshere" marker in the current frame.
887 */
888 if (validate_sp(sp, tsk, INT_FRAME_SIZE)
889 && stack[FRAME_MARKER] == REGS_MARKER) {
890 struct pt_regs *regs = (struct pt_regs *)
891 (sp + STACK_FRAME_OVERHEAD);
892 printk("--- Exception: %lx", regs->trap);
893 print_symbol(" at %s\n", regs->nip);
894 lr = regs->link;
895 print_symbol(" LR = %s\n", lr);
896 firstframe = 1;
897 }
898
899 sp = newsp;
900 } while (count++ < kstack_depth_to_print);
901}
902
903void dump_stack(void)
904{
905 show_stack(current, NULL);
906}
907EXPORT_SYMBOL(dump_stack);
kernel source for telekom puls (alcatel/mediatek)