Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/audit
[cascardo/linux.git] / arch / sparc / kernel / process_64.c
1 /*  arch/sparc64/kernel/process.c
2  *
3  *  Copyright (C) 1995, 1996, 2008 David S. Miller (davem@davemloft.net)
4  *  Copyright (C) 1996       Eddie C. Dost   (ecd@skynet.be)
5  *  Copyright (C) 1997, 1998 Jakub Jelinek   (jj@sunsite.mff.cuni.cz)
6  */
7
8 /*
9  * This file handles the architecture-dependent parts of process handling..
10  */
11
12 #include <stdarg.h>
13
14 #include <linux/errno.h>
15 #include <linux/export.h>
16 #include <linux/sched.h>
17 #include <linux/kernel.h>
18 #include <linux/mm.h>
19 #include <linux/fs.h>
20 #include <linux/smp.h>
21 #include <linux/stddef.h>
22 #include <linux/ptrace.h>
23 #include <linux/slab.h>
24 #include <linux/user.h>
25 #include <linux/delay.h>
26 #include <linux/compat.h>
27 #include <linux/tick.h>
28 #include <linux/init.h>
29 #include <linux/cpu.h>
30 #include <linux/perf_event.h>
31 #include <linux/elfcore.h>
32 #include <linux/sysrq.h>
33 #include <linux/nmi.h>
34 #include <linux/context_tracking.h>
35
36 #include <asm/uaccess.h>
37 #include <asm/page.h>
38 #include <asm/pgalloc.h>
39 #include <asm/pgtable.h>
40 #include <asm/processor.h>
41 #include <asm/pstate.h>
42 #include <asm/elf.h>
43 #include <asm/fpumacro.h>
44 #include <asm/head.h>
45 #include <asm/cpudata.h>
46 #include <asm/mmu_context.h>
47 #include <asm/unistd.h>
48 #include <asm/hypervisor.h>
49 #include <asm/syscalls.h>
50 #include <asm/irq_regs.h>
51 #include <asm/smp.h>
52 #include <asm/pcr.h>
53
54 #include "kstack.h"
55
56 /* Idle loop support on sparc64. */
57 void arch_cpu_idle(void)
58 {
59         if (tlb_type != hypervisor) {
60                 touch_nmi_watchdog();
61                 local_irq_enable();
62         } else {
63                 unsigned long pstate;
64
65                 local_irq_enable();
66
67                 /* The sun4v sleeping code requires that we have PSTATE.IE cleared over
68                  * the cpu sleep hypervisor call.
69                  */
70                 __asm__ __volatile__(
71                         "rdpr %%pstate, %0\n\t"
72                         "andn %0, %1, %0\n\t"
73                         "wrpr %0, %%g0, %%pstate"
74                         : "=&r" (pstate)
75                         : "i" (PSTATE_IE));
76
77                 if (!need_resched() && !cpu_is_offline(smp_processor_id()))
78                         sun4v_cpu_yield();
79
80                 /* Re-enable interrupts. */
81                 __asm__ __volatile__(
82                         "rdpr %%pstate, %0\n\t"
83                         "or %0, %1, %0\n\t"
84                         "wrpr %0, %%g0, %%pstate"
85                         : "=&r" (pstate)
86                         : "i" (PSTATE_IE));
87         }
88 }
89
90 #ifdef CONFIG_HOTPLUG_CPU
91 void arch_cpu_idle_dead(void)
92 {
93         sched_preempt_enable_no_resched();
94         cpu_play_dead();
95 }
96 #endif
97
98 #ifdef CONFIG_COMPAT
99 static void show_regwindow32(struct pt_regs *regs)
100 {
101         struct reg_window32 __user *rw;
102         struct reg_window32 r_w;
103         mm_segment_t old_fs;
104         
105         __asm__ __volatile__ ("flushw");
106         rw = compat_ptr((unsigned int)regs->u_regs[14]);
107         old_fs = get_fs();
108         set_fs (USER_DS);
109         if (copy_from_user (&r_w, rw, sizeof(r_w))) {
110                 set_fs (old_fs);
111                 return;
112         }
113
114         set_fs (old_fs);                        
115         printk("l0: %08x l1: %08x l2: %08x l3: %08x "
116                "l4: %08x l5: %08x l6: %08x l7: %08x\n",
117                r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
118                r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
119         printk("i0: %08x i1: %08x i2: %08x i3: %08x "
120                "i4: %08x i5: %08x i6: %08x i7: %08x\n",
121                r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
122                r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
123 }
124 #else
125 #define show_regwindow32(regs)  do { } while (0)
126 #endif
127
128 static void show_regwindow(struct pt_regs *regs)
129 {
130         struct reg_window __user *rw;
131         struct reg_window *rwk;
132         struct reg_window r_w;
133         mm_segment_t old_fs;
134
135         if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
136                 __asm__ __volatile__ ("flushw");
137                 rw = (struct reg_window __user *)
138                         (regs->u_regs[14] + STACK_BIAS);
139                 rwk = (struct reg_window *)
140                         (regs->u_regs[14] + STACK_BIAS);
141                 if (!(regs->tstate & TSTATE_PRIV)) {
142                         old_fs = get_fs();
143                         set_fs (USER_DS);
144                         if (copy_from_user (&r_w, rw, sizeof(r_w))) {
145                                 set_fs (old_fs);
146                                 return;
147                         }
148                         rwk = &r_w;
149                         set_fs (old_fs);                        
150                 }
151         } else {
152                 show_regwindow32(regs);
153                 return;
154         }
155         printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
156                rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
157         printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
158                rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
159         printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
160                rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
161         printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
162                rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
163         if (regs->tstate & TSTATE_PRIV)
164                 printk("I7: <%pS>\n", (void *) rwk->ins[7]);
165 }
166
167 void show_regs(struct pt_regs *regs)
168 {
169         show_regs_print_info(KERN_DEFAULT);
170
171         printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x    %s\n", regs->tstate,
172                regs->tpc, regs->tnpc, regs->y, print_tainted());
173         printk("TPC: <%pS>\n", (void *) regs->tpc);
174         printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
175                regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
176                regs->u_regs[3]);
177         printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
178                regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
179                regs->u_regs[7]);
180         printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
181                regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
182                regs->u_regs[11]);
183         printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
184                regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
185                regs->u_regs[15]);
186         printk("RPC: <%pS>\n", (void *) regs->u_regs[15]);
187         show_regwindow(regs);
188         show_stack(current, (unsigned long *) regs->u_regs[UREG_FP]);
189 }
190
191 union global_cpu_snapshot global_cpu_snapshot[NR_CPUS];
192 static DEFINE_SPINLOCK(global_cpu_snapshot_lock);
193
194 static void __global_reg_self(struct thread_info *tp, struct pt_regs *regs,
195                               int this_cpu)
196 {
197         struct global_reg_snapshot *rp;
198
199         flushw_all();
200
201         rp = &global_cpu_snapshot[this_cpu].reg;
202
203         rp->tstate = regs->tstate;
204         rp->tpc = regs->tpc;
205         rp->tnpc = regs->tnpc;
206         rp->o7 = regs->u_regs[UREG_I7];
207
208         if (regs->tstate & TSTATE_PRIV) {
209                 struct reg_window *rw;
210
211                 rw = (struct reg_window *)
212                         (regs->u_regs[UREG_FP] + STACK_BIAS);
213                 if (kstack_valid(tp, (unsigned long) rw)) {
214                         rp->i7 = rw->ins[7];
215                         rw = (struct reg_window *)
216                                 (rw->ins[6] + STACK_BIAS);
217                         if (kstack_valid(tp, (unsigned long) rw))
218                                 rp->rpc = rw->ins[7];
219                 }
220         } else {
221                 rp->i7 = 0;
222                 rp->rpc = 0;
223         }
224         rp->thread = tp;
225 }
226
227 /* In order to avoid hangs we do not try to synchronize with the
228  * global register dump client cpus.  The last store they make is to
229  * the thread pointer, so do a short poll waiting for that to become
230  * non-NULL.
231  */
232 static void __global_reg_poll(struct global_reg_snapshot *gp)
233 {
234         int limit = 0;
235
236         while (!gp->thread && ++limit < 100) {
237                 barrier();
238                 udelay(1);
239         }
240 }
241
242 void arch_trigger_all_cpu_backtrace(bool include_self)
243 {
244         struct thread_info *tp = current_thread_info();
245         struct pt_regs *regs = get_irq_regs();
246         unsigned long flags;
247         int this_cpu, cpu;
248
249         if (!regs)
250                 regs = tp->kregs;
251
252         spin_lock_irqsave(&global_cpu_snapshot_lock, flags);
253
254         this_cpu = raw_smp_processor_id();
255
256         memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
257
258         if (include_self)
259                 __global_reg_self(tp, regs, this_cpu);
260
261         smp_fetch_global_regs();
262
263         for_each_online_cpu(cpu) {
264                 struct global_reg_snapshot *gp;
265
266                 if (!include_self && cpu == this_cpu)
267                         continue;
268
269                 gp = &global_cpu_snapshot[cpu].reg;
270
271                 __global_reg_poll(gp);
272
273                 tp = gp->thread;
274                 printk("%c CPU[%3d]: TSTATE[%016lx] TPC[%016lx] TNPC[%016lx] TASK[%s:%d]\n",
275                        (cpu == this_cpu ? '*' : ' '), cpu,
276                        gp->tstate, gp->tpc, gp->tnpc,
277                        ((tp && tp->task) ? tp->task->comm : "NULL"),
278                        ((tp && tp->task) ? tp->task->pid : -1));
279
280                 if (gp->tstate & TSTATE_PRIV) {
281                         printk("             TPC[%pS] O7[%pS] I7[%pS] RPC[%pS]\n",
282                                (void *) gp->tpc,
283                                (void *) gp->o7,
284                                (void *) gp->i7,
285                                (void *) gp->rpc);
286                 } else {
287                         printk("             TPC[%lx] O7[%lx] I7[%lx] RPC[%lx]\n",
288                                gp->tpc, gp->o7, gp->i7, gp->rpc);
289                 }
290
291                 touch_nmi_watchdog();
292         }
293
294         memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
295
296         spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags);
297 }
298
299 #ifdef CONFIG_MAGIC_SYSRQ
300
301 static void sysrq_handle_globreg(int key)
302 {
303         arch_trigger_all_cpu_backtrace(true);
304 }
305
306 static struct sysrq_key_op sparc_globalreg_op = {
307         .handler        = sysrq_handle_globreg,
308         .help_msg       = "global-regs(y)",
309         .action_msg     = "Show Global CPU Regs",
310 };
311
312 static void __global_pmu_self(int this_cpu)
313 {
314         struct global_pmu_snapshot *pp;
315         int i, num;
316
317         if (!pcr_ops)
318                 return;
319
320         pp = &global_cpu_snapshot[this_cpu].pmu;
321
322         num = 1;
323         if (tlb_type == hypervisor &&
324             sun4v_chip_type >= SUN4V_CHIP_NIAGARA4)
325                 num = 4;
326
327         for (i = 0; i < num; i++) {
328                 pp->pcr[i] = pcr_ops->read_pcr(i);
329                 pp->pic[i] = pcr_ops->read_pic(i);
330         }
331 }
332
333 static void __global_pmu_poll(struct global_pmu_snapshot *pp)
334 {
335         int limit = 0;
336
337         while (!pp->pcr[0] && ++limit < 100) {
338                 barrier();
339                 udelay(1);
340         }
341 }
342
343 static void pmu_snapshot_all_cpus(void)
344 {
345         unsigned long flags;
346         int this_cpu, cpu;
347
348         spin_lock_irqsave(&global_cpu_snapshot_lock, flags);
349
350         memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
351
352         this_cpu = raw_smp_processor_id();
353
354         __global_pmu_self(this_cpu);
355
356         smp_fetch_global_pmu();
357
358         for_each_online_cpu(cpu) {
359                 struct global_pmu_snapshot *pp = &global_cpu_snapshot[cpu].pmu;
360
361                 __global_pmu_poll(pp);
362
363                 printk("%c CPU[%3d]: PCR[%08lx:%08lx:%08lx:%08lx] PIC[%08lx:%08lx:%08lx:%08lx]\n",
364                        (cpu == this_cpu ? '*' : ' '), cpu,
365                        pp->pcr[0], pp->pcr[1], pp->pcr[2], pp->pcr[3],
366                        pp->pic[0], pp->pic[1], pp->pic[2], pp->pic[3]);
367
368                 touch_nmi_watchdog();
369         }
370
371         memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
372
373         spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags);
374 }
375
376 static void sysrq_handle_globpmu(int key)
377 {
378         pmu_snapshot_all_cpus();
379 }
380
381 static struct sysrq_key_op sparc_globalpmu_op = {
382         .handler        = sysrq_handle_globpmu,
383         .help_msg       = "global-pmu(x)",
384         .action_msg     = "Show Global PMU Regs",
385 };
386
387 static int __init sparc_sysrq_init(void)
388 {
389         int ret = register_sysrq_key('y', &sparc_globalreg_op);
390
391         if (!ret)
392                 ret = register_sysrq_key('x', &sparc_globalpmu_op);
393         return ret;
394 }
395
396 core_initcall(sparc_sysrq_init);
397
398 #endif
399
400 unsigned long thread_saved_pc(struct task_struct *tsk)
401 {
402         struct thread_info *ti = task_thread_info(tsk);
403         unsigned long ret = 0xdeadbeefUL;
404         
405         if (ti && ti->ksp) {
406                 unsigned long *sp;
407                 sp = (unsigned long *)(ti->ksp + STACK_BIAS);
408                 if (((unsigned long)sp & (sizeof(long) - 1)) == 0UL &&
409                     sp[14]) {
410                         unsigned long *fp;
411                         fp = (unsigned long *)(sp[14] + STACK_BIAS);
412                         if (((unsigned long)fp & (sizeof(long) - 1)) == 0UL)
413                                 ret = fp[15];
414                 }
415         }
416         return ret;
417 }
418
419 /* Free current thread data structures etc.. */
420 void exit_thread(struct task_struct *tsk)
421 {
422         struct thread_info *t = task_thread_info(tsk);
423
424         if (t->utraps) {
425                 if (t->utraps[0] < 2)
426                         kfree (t->utraps);
427                 else
428                         t->utraps[0]--;
429         }
430 }
431
432 void flush_thread(void)
433 {
434         struct thread_info *t = current_thread_info();
435         struct mm_struct *mm;
436
437         mm = t->task->mm;
438         if (mm)
439                 tsb_context_switch(mm);
440
441         set_thread_wsaved(0);
442
443         /* Clear FPU register state. */
444         t->fpsaved[0] = 0;
445 }
446
447 /* It's a bit more tricky when 64-bit tasks are involved... */
448 static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
449 {
450         bool stack_64bit = test_thread_64bit_stack(psp);
451         unsigned long fp, distance, rval;
452
453         if (stack_64bit) {
454                 csp += STACK_BIAS;
455                 psp += STACK_BIAS;
456                 __get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
457                 fp += STACK_BIAS;
458                 if (test_thread_flag(TIF_32BIT))
459                         fp &= 0xffffffff;
460         } else
461                 __get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
462
463         /* Now align the stack as this is mandatory in the Sparc ABI
464          * due to how register windows work.  This hides the
465          * restriction from thread libraries etc.
466          */
467         csp &= ~15UL;
468
469         distance = fp - psp;
470         rval = (csp - distance);
471         if (copy_in_user((void __user *) rval, (void __user *) psp, distance))
472                 rval = 0;
473         else if (!stack_64bit) {
474                 if (put_user(((u32)csp),
475                              &(((struct reg_window32 __user *)rval)->ins[6])))
476                         rval = 0;
477         } else {
478                 if (put_user(((u64)csp - STACK_BIAS),
479                              &(((struct reg_window __user *)rval)->ins[6])))
480                         rval = 0;
481                 else
482                         rval = rval - STACK_BIAS;
483         }
484
485         return rval;
486 }
487
488 /* Standard stuff. */
489 static inline void shift_window_buffer(int first_win, int last_win,
490                                        struct thread_info *t)
491 {
492         int i;
493
494         for (i = first_win; i < last_win; i++) {
495                 t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
496                 memcpy(&t->reg_window[i], &t->reg_window[i+1],
497                        sizeof(struct reg_window));
498         }
499 }
500
501 void synchronize_user_stack(void)
502 {
503         struct thread_info *t = current_thread_info();
504         unsigned long window;
505
506         flush_user_windows();
507         if ((window = get_thread_wsaved()) != 0) {
508                 window -= 1;
509                 do {
510                         struct reg_window *rwin = &t->reg_window[window];
511                         int winsize = sizeof(struct reg_window);
512                         unsigned long sp;
513
514                         sp = t->rwbuf_stkptrs[window];
515
516                         if (test_thread_64bit_stack(sp))
517                                 sp += STACK_BIAS;
518                         else
519                                 winsize = sizeof(struct reg_window32);
520
521                         if (!copy_to_user((char __user *)sp, rwin, winsize)) {
522                                 shift_window_buffer(window, get_thread_wsaved() - 1, t);
523                                 set_thread_wsaved(get_thread_wsaved() - 1);
524                         }
525                 } while (window--);
526         }
527 }
528
529 static void stack_unaligned(unsigned long sp)
530 {
531         siginfo_t info;
532
533         info.si_signo = SIGBUS;
534         info.si_errno = 0;
535         info.si_code = BUS_ADRALN;
536         info.si_addr = (void __user *) sp;
537         info.si_trapno = 0;
538         force_sig_info(SIGBUS, &info, current);
539 }
540
541 void fault_in_user_windows(void)
542 {
543         struct thread_info *t = current_thread_info();
544         unsigned long window;
545
546         flush_user_windows();
547         window = get_thread_wsaved();
548
549         if (likely(window != 0)) {
550                 window -= 1;
551                 do {
552                         struct reg_window *rwin = &t->reg_window[window];
553                         int winsize = sizeof(struct reg_window);
554                         unsigned long sp;
555
556                         sp = t->rwbuf_stkptrs[window];
557
558                         if (test_thread_64bit_stack(sp))
559                                 sp += STACK_BIAS;
560                         else
561                                 winsize = sizeof(struct reg_window32);
562
563                         if (unlikely(sp & 0x7UL))
564                                 stack_unaligned(sp);
565
566                         if (unlikely(copy_to_user((char __user *)sp,
567                                                   rwin, winsize)))
568                                 goto barf;
569                 } while (window--);
570         }
571         set_thread_wsaved(0);
572         return;
573
574 barf:
575         set_thread_wsaved(window + 1);
576         user_exit();
577         do_exit(SIGILL);
578 }
579
580 asmlinkage long sparc_do_fork(unsigned long clone_flags,
581                               unsigned long stack_start,
582                               struct pt_regs *regs,
583                               unsigned long stack_size)
584 {
585         int __user *parent_tid_ptr, *child_tid_ptr;
586         unsigned long orig_i1 = regs->u_regs[UREG_I1];
587         long ret;
588
589 #ifdef CONFIG_COMPAT
590         if (test_thread_flag(TIF_32BIT)) {
591                 parent_tid_ptr = compat_ptr(regs->u_regs[UREG_I2]);
592                 child_tid_ptr = compat_ptr(regs->u_regs[UREG_I4]);
593         } else
594 #endif
595         {
596                 parent_tid_ptr = (int __user *) regs->u_regs[UREG_I2];
597                 child_tid_ptr = (int __user *) regs->u_regs[UREG_I4];
598         }
599
600         ret = do_fork(clone_flags, stack_start, stack_size,
601                       parent_tid_ptr, child_tid_ptr);
602
603         /* If we get an error and potentially restart the system
604          * call, we're screwed because copy_thread() clobbered
605          * the parent's %o1.  So detect that case and restore it
606          * here.
607          */
608         if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
609                 regs->u_regs[UREG_I1] = orig_i1;
610
611         return ret;
612 }
613
614 /* Copy a Sparc thread.  The fork() return value conventions
615  * under SunOS are nothing short of bletcherous:
616  * Parent -->  %o0 == childs  pid, %o1 == 0
617  * Child  -->  %o0 == parents pid, %o1 == 1
618  */
619 int copy_thread(unsigned long clone_flags, unsigned long sp,
620                 unsigned long arg, struct task_struct *p)
621 {
622         struct thread_info *t = task_thread_info(p);
623         struct pt_regs *regs = current_pt_regs();
624         struct sparc_stackf *parent_sf;
625         unsigned long child_stack_sz;
626         char *child_trap_frame;
627
628         /* Calculate offset to stack_frame & pt_regs */
629         child_stack_sz = (STACKFRAME_SZ + TRACEREG_SZ);
630         child_trap_frame = (task_stack_page(p) +
631                             (THREAD_SIZE - child_stack_sz));
632
633         t->new_child = 1;
634         t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
635         t->kregs = (struct pt_regs *) (child_trap_frame +
636                                        sizeof(struct sparc_stackf));
637         t->fpsaved[0] = 0;
638
639         if (unlikely(p->flags & PF_KTHREAD)) {
640                 memset(child_trap_frame, 0, child_stack_sz);
641                 __thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] = 
642                         (current_pt_regs()->tstate + 1) & TSTATE_CWP;
643                 t->current_ds = ASI_P;
644                 t->kregs->u_regs[UREG_G1] = sp; /* function */
645                 t->kregs->u_regs[UREG_G2] = arg;
646                 return 0;
647         }
648
649         parent_sf = ((struct sparc_stackf *) regs) - 1;
650         memcpy(child_trap_frame, parent_sf, child_stack_sz);
651         if (t->flags & _TIF_32BIT) {
652                 sp &= 0x00000000ffffffffUL;
653                 regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
654         }
655         t->kregs->u_regs[UREG_FP] = sp;
656         __thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] = 
657                 (regs->tstate + 1) & TSTATE_CWP;
658         t->current_ds = ASI_AIUS;
659         if (sp != regs->u_regs[UREG_FP]) {
660                 unsigned long csp;
661
662                 csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
663                 if (!csp)
664                         return -EFAULT;
665                 t->kregs->u_regs[UREG_FP] = csp;
666         }
667         if (t->utraps)
668                 t->utraps[0]++;
669
670         /* Set the return value for the child. */
671         t->kregs->u_regs[UREG_I0] = current->pid;
672         t->kregs->u_regs[UREG_I1] = 1;
673
674         /* Set the second return value for the parent. */
675         regs->u_regs[UREG_I1] = 0;
676
677         if (clone_flags & CLONE_SETTLS)
678                 t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
679
680         return 0;
681 }
682
683 typedef struct {
684         union {
685                 unsigned int    pr_regs[32];
686                 unsigned long   pr_dregs[16];
687         } pr_fr;
688         unsigned int __unused;
689         unsigned int    pr_fsr;
690         unsigned char   pr_qcnt;
691         unsigned char   pr_q_entrysize;
692         unsigned char   pr_en;
693         unsigned int    pr_q[64];
694 } elf_fpregset_t32;
695
696 /*
697  * fill in the fpu structure for a core dump.
698  */
699 int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
700 {
701         unsigned long *kfpregs = current_thread_info()->fpregs;
702         unsigned long fprs = current_thread_info()->fpsaved[0];
703
704         if (test_thread_flag(TIF_32BIT)) {
705                 elf_fpregset_t32 *fpregs32 = (elf_fpregset_t32 *)fpregs;
706
707                 if (fprs & FPRS_DL)
708                         memcpy(&fpregs32->pr_fr.pr_regs[0], kfpregs,
709                                sizeof(unsigned int) * 32);
710                 else
711                         memset(&fpregs32->pr_fr.pr_regs[0], 0,
712                                sizeof(unsigned int) * 32);
713                 fpregs32->pr_qcnt = 0;
714                 fpregs32->pr_q_entrysize = 8;
715                 memset(&fpregs32->pr_q[0], 0,
716                        (sizeof(unsigned int) * 64));
717                 if (fprs & FPRS_FEF) {
718                         fpregs32->pr_fsr = (unsigned int) current_thread_info()->xfsr[0];
719                         fpregs32->pr_en = 1;
720                 } else {
721                         fpregs32->pr_fsr = 0;
722                         fpregs32->pr_en = 0;
723                 }
724         } else {
725                 if(fprs & FPRS_DL)
726                         memcpy(&fpregs->pr_regs[0], kfpregs,
727                                sizeof(unsigned int) * 32);
728                 else
729                         memset(&fpregs->pr_regs[0], 0,
730                                sizeof(unsigned int) * 32);
731                 if(fprs & FPRS_DU)
732                         memcpy(&fpregs->pr_regs[16], kfpregs+16,
733                                sizeof(unsigned int) * 32);
734                 else
735                         memset(&fpregs->pr_regs[16], 0,
736                                sizeof(unsigned int) * 32);
737                 if(fprs & FPRS_FEF) {
738                         fpregs->pr_fsr = current_thread_info()->xfsr[0];
739                         fpregs->pr_gsr = current_thread_info()->gsr[0];
740                 } else {
741                         fpregs->pr_fsr = fpregs->pr_gsr = 0;
742                 }
743                 fpregs->pr_fprs = fprs;
744         }
745         return 1;
746 }
747 EXPORT_SYMBOL(dump_fpu);
748
749 unsigned long get_wchan(struct task_struct *task)
750 {
751         unsigned long pc, fp, bias = 0;
752         struct thread_info *tp;
753         struct reg_window *rw;
754         unsigned long ret = 0;
755         int count = 0; 
756
757         if (!task || task == current ||
758             task->state == TASK_RUNNING)
759                 goto out;
760
761         tp = task_thread_info(task);
762         bias = STACK_BIAS;
763         fp = task_thread_info(task)->ksp + bias;
764
765         do {
766                 if (!kstack_valid(tp, fp))
767                         break;
768                 rw = (struct reg_window *) fp;
769                 pc = rw->ins[7];
770                 if (!in_sched_functions(pc)) {
771                         ret = pc;
772                         goto out;
773                 }
774                 fp = rw->ins[6] + bias;
775         } while (++count < 16);
776
777 out:
778         return ret;
779 }