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v6.2
  1// SPDX-License-Identifier: GPL-2.0
  2/*  arch/sparc64/kernel/process.c
  3 *
  4 *  Copyright (C) 1995, 1996, 2008 David S. Miller (davem@davemloft.net)
  5 *  Copyright (C) 1996       Eddie C. Dost   (ecd@skynet.be)
  6 *  Copyright (C) 1997, 1998 Jakub Jelinek   (jj@sunsite.mff.cuni.cz)
  7 */
  8
  9/*
 10 * This file handles the architecture-dependent parts of process handling..
 11 */
 
 
 
 12#include <linux/errno.h>
 13#include <linux/export.h>
 14#include <linux/sched.h>
 15#include <linux/sched/debug.h>
 16#include <linux/sched/task.h>
 17#include <linux/sched/task_stack.h>
 18#include <linux/kernel.h>
 19#include <linux/mm.h>
 20#include <linux/fs.h>
 21#include <linux/smp.h>
 22#include <linux/stddef.h>
 23#include <linux/ptrace.h>
 24#include <linux/slab.h>
 25#include <linux/user.h>
 26#include <linux/delay.h>
 27#include <linux/compat.h>
 28#include <linux/tick.h>
 29#include <linux/init.h>
 30#include <linux/cpu.h>
 31#include <linux/perf_event.h>
 32#include <linux/elfcore.h>
 33#include <linux/sysrq.h>
 34#include <linux/nmi.h>
 35#include <linux/context_tracking.h>
 36#include <linux/signal.h>
 37
 38#include <linux/uaccess.h>
 39#include <asm/page.h>
 40#include <asm/pgalloc.h>
 
 41#include <asm/processor.h>
 42#include <asm/pstate.h>
 43#include <asm/elf.h>
 44#include <asm/fpumacro.h>
 45#include <asm/head.h>
 46#include <asm/cpudata.h>
 47#include <asm/mmu_context.h>
 48#include <asm/unistd.h>
 49#include <asm/hypervisor.h>
 50#include <asm/syscalls.h>
 51#include <asm/irq_regs.h>
 52#include <asm/smp.h>
 53#include <asm/pcr.h>
 54
 55#include "kstack.h"
 56
 57/* Idle loop support on sparc64. */
 58void arch_cpu_idle(void)
 59{
 60	if (tlb_type != hypervisor) {
 61		touch_nmi_watchdog();
 62		raw_local_irq_enable();
 63	} else {
 64		unsigned long pstate;
 65
 66		raw_local_irq_enable();
 67
 68                /* The sun4v sleeping code requires that we have PSTATE.IE cleared over
 69                 * the cpu sleep hypervisor call.
 70                 */
 71		__asm__ __volatile__(
 72			"rdpr %%pstate, %0\n\t"
 73			"andn %0, %1, %0\n\t"
 74			"wrpr %0, %%g0, %%pstate"
 75			: "=&r" (pstate)
 76			: "i" (PSTATE_IE));
 77
 78		if (!need_resched() && !cpu_is_offline(smp_processor_id())) {
 79			sun4v_cpu_yield();
 80			/* If resumed by cpu_poke then we need to explicitly
 81			 * call scheduler_ipi().
 82			 */
 83			scheduler_poke();
 84		}
 85
 86		/* Re-enable interrupts. */
 87		__asm__ __volatile__(
 88			"rdpr %%pstate, %0\n\t"
 89			"or %0, %1, %0\n\t"
 90			"wrpr %0, %%g0, %%pstate"
 91			: "=&r" (pstate)
 92			: "i" (PSTATE_IE));
 93	}
 94}
 95
 96#ifdef CONFIG_HOTPLUG_CPU
 97void arch_cpu_idle_dead(void)
 98{
 99	sched_preempt_enable_no_resched();
100	cpu_play_dead();
101}
102#endif
103
104#ifdef CONFIG_COMPAT
105static void show_regwindow32(struct pt_regs *regs)
106{
107	struct reg_window32 __user *rw;
108	struct reg_window32 r_w;
 
109	
110	__asm__ __volatile__ ("flushw");
111	rw = compat_ptr((unsigned int)regs->u_regs[14]);
 
 
112	if (copy_from_user (&r_w, rw, sizeof(r_w))) {
 
113		return;
114	}
115
 
116	printk("l0: %08x l1: %08x l2: %08x l3: %08x "
117	       "l4: %08x l5: %08x l6: %08x l7: %08x\n",
118	       r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
119	       r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
120	printk("i0: %08x i1: %08x i2: %08x i3: %08x "
121	       "i4: %08x i5: %08x i6: %08x i7: %08x\n",
122	       r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
123	       r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
124}
125#else
126#define show_regwindow32(regs)	do { } while (0)
127#endif
128
129static void show_regwindow(struct pt_regs *regs)
130{
131	struct reg_window __user *rw;
132	struct reg_window *rwk;
133	struct reg_window r_w;
 
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			if (copy_from_user (&r_w, rw, sizeof(r_w))) {
 
143				return;
144			}
145			rwk = &r_w;
 
146		}
147	} else {
148		show_regwindow32(regs);
149		return;
150	}
151	printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
152	       rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
153	printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
154	       rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
155	printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
156	       rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
157	printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
158	       rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
159	if (regs->tstate & TSTATE_PRIV)
160		printk("I7: <%pS>\n", (void *) rwk->ins[7]);
161}
162
163void show_regs(struct pt_regs *regs)
164{
165	show_regs_print_info(KERN_DEFAULT);
166
167	printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x    %s\n", regs->tstate,
168	       regs->tpc, regs->tnpc, regs->y, print_tainted());
169	printk("TPC: <%pS>\n", (void *) regs->tpc);
170	printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
171	       regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
172	       regs->u_regs[3]);
173	printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
174	       regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
175	       regs->u_regs[7]);
176	printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
177	       regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
178	       regs->u_regs[11]);
179	printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
180	       regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
181	       regs->u_regs[15]);
182	printk("RPC: <%pS>\n", (void *) regs->u_regs[15]);
183	show_regwindow(regs);
184	show_stack(current, (unsigned long *)regs->u_regs[UREG_FP], KERN_DEFAULT);
185}
186
187union global_cpu_snapshot global_cpu_snapshot[NR_CPUS];
188static DEFINE_SPINLOCK(global_cpu_snapshot_lock);
189
190static void __global_reg_self(struct thread_info *tp, struct pt_regs *regs,
191			      int this_cpu)
192{
193	struct global_reg_snapshot *rp;
194
195	flushw_all();
196
197	rp = &global_cpu_snapshot[this_cpu].reg;
198
199	rp->tstate = regs->tstate;
200	rp->tpc = regs->tpc;
201	rp->tnpc = regs->tnpc;
202	rp->o7 = regs->u_regs[UREG_I7];
203
204	if (regs->tstate & TSTATE_PRIV) {
205		struct reg_window *rw;
206
207		rw = (struct reg_window *)
208			(regs->u_regs[UREG_FP] + STACK_BIAS);
209		if (kstack_valid(tp, (unsigned long) rw)) {
210			rp->i7 = rw->ins[7];
211			rw = (struct reg_window *)
212				(rw->ins[6] + STACK_BIAS);
213			if (kstack_valid(tp, (unsigned long) rw))
214				rp->rpc = rw->ins[7];
215		}
216	} else {
217		rp->i7 = 0;
218		rp->rpc = 0;
219	}
220	rp->thread = tp;
221}
222
223/* In order to avoid hangs we do not try to synchronize with the
224 * global register dump client cpus.  The last store they make is to
225 * the thread pointer, so do a short poll waiting for that to become
226 * non-NULL.
227 */
228static void __global_reg_poll(struct global_reg_snapshot *gp)
229{
230	int limit = 0;
231
232	while (!gp->thread && ++limit < 100) {
233		barrier();
234		udelay(1);
235	}
236}
237
238void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
239{
240	struct thread_info *tp = current_thread_info();
241	struct pt_regs *regs = get_irq_regs();
242	unsigned long flags;
243	int this_cpu, cpu;
244
245	if (!regs)
246		regs = tp->kregs;
247
248	spin_lock_irqsave(&global_cpu_snapshot_lock, flags);
249
250	this_cpu = raw_smp_processor_id();
251
252	memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
253
254	if (cpumask_test_cpu(this_cpu, mask) && !exclude_self)
255		__global_reg_self(tp, regs, this_cpu);
256
257	smp_fetch_global_regs();
258
259	for_each_cpu(cpu, mask) {
260		struct global_reg_snapshot *gp;
261
262		if (exclude_self && cpu == this_cpu)
263			continue;
264
265		gp = &global_cpu_snapshot[cpu].reg;
 
266
267		__global_reg_poll(gp);
268
269		tp = gp->thread;
270		printk("%c CPU[%3d]: TSTATE[%016lx] TPC[%016lx] TNPC[%016lx] TASK[%s:%d]\n",
271		       (cpu == this_cpu ? '*' : ' '), cpu,
272		       gp->tstate, gp->tpc, gp->tnpc,
273		       ((tp && tp->task) ? tp->task->comm : "NULL"),
274		       ((tp && tp->task) ? tp->task->pid : -1));
275
276		if (gp->tstate & TSTATE_PRIV) {
277			printk("             TPC[%pS] O7[%pS] I7[%pS] RPC[%pS]\n",
278			       (void *) gp->tpc,
279			       (void *) gp->o7,
280			       (void *) gp->i7,
281			       (void *) gp->rpc);
282		} else {
283			printk("             TPC[%lx] O7[%lx] I7[%lx] RPC[%lx]\n",
284			       gp->tpc, gp->o7, gp->i7, gp->rpc);
285		}
286
287		touch_nmi_watchdog();
288	}
289
290	memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
291
292	spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags);
293}
294
295#ifdef CONFIG_MAGIC_SYSRQ
296
297static void sysrq_handle_globreg(int key)
298{
299	trigger_all_cpu_backtrace();
300}
301
302static const struct sysrq_key_op sparc_globalreg_op = {
303	.handler	= sysrq_handle_globreg,
304	.help_msg	= "global-regs(y)",
305	.action_msg	= "Show Global CPU Regs",
306};
307
308static void __global_pmu_self(int this_cpu)
309{
310	struct global_pmu_snapshot *pp;
311	int i, num;
312
313	if (!pcr_ops)
314		return;
315
316	pp = &global_cpu_snapshot[this_cpu].pmu;
317
318	num = 1;
319	if (tlb_type == hypervisor &&
320	    sun4v_chip_type >= SUN4V_CHIP_NIAGARA4)
321		num = 4;
322
323	for (i = 0; i < num; i++) {
324		pp->pcr[i] = pcr_ops->read_pcr(i);
325		pp->pic[i] = pcr_ops->read_pic(i);
326	}
327}
328
329static void __global_pmu_poll(struct global_pmu_snapshot *pp)
330{
331	int limit = 0;
332
333	while (!pp->pcr[0] && ++limit < 100) {
334		barrier();
335		udelay(1);
336	}
337}
338
339static void pmu_snapshot_all_cpus(void)
340{
341	unsigned long flags;
342	int this_cpu, cpu;
343
344	spin_lock_irqsave(&global_cpu_snapshot_lock, flags);
345
346	memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
347
348	this_cpu = raw_smp_processor_id();
349
350	__global_pmu_self(this_cpu);
351
352	smp_fetch_global_pmu();
353
354	for_each_online_cpu(cpu) {
355		struct global_pmu_snapshot *pp = &global_cpu_snapshot[cpu].pmu;
356
357		__global_pmu_poll(pp);
358
359		printk("%c CPU[%3d]: PCR[%08lx:%08lx:%08lx:%08lx] PIC[%08lx:%08lx:%08lx:%08lx]\n",
360		       (cpu == this_cpu ? '*' : ' '), cpu,
361		       pp->pcr[0], pp->pcr[1], pp->pcr[2], pp->pcr[3],
362		       pp->pic[0], pp->pic[1], pp->pic[2], pp->pic[3]);
363
364		touch_nmi_watchdog();
365	}
366
367	memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
368
369	spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags);
370}
371
372static void sysrq_handle_globpmu(int key)
373{
374	pmu_snapshot_all_cpus();
375}
376
377static const struct sysrq_key_op sparc_globalpmu_op = {
378	.handler	= sysrq_handle_globpmu,
379	.help_msg	= "global-pmu(x)",
380	.action_msg	= "Show Global PMU Regs",
381};
382
383static int __init sparc_sysrq_init(void)
384{
385	int ret = register_sysrq_key('y', &sparc_globalreg_op);
386
387	if (!ret)
388		ret = register_sysrq_key('x', &sparc_globalpmu_op);
389	return ret;
390}
391
392core_initcall(sparc_sysrq_init);
393
394#endif
395
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
396/* Free current thread data structures etc.. */
397void exit_thread(struct task_struct *tsk)
398{
399	struct thread_info *t = task_thread_info(tsk);
400
401	if (t->utraps) {
402		if (t->utraps[0] < 2)
403			kfree (t->utraps);
404		else
405			t->utraps[0]--;
406	}
407}
408
409void flush_thread(void)
410{
411	struct thread_info *t = current_thread_info();
412	struct mm_struct *mm;
413
414	mm = t->task->mm;
415	if (mm)
416		tsb_context_switch(mm);
417
418	set_thread_wsaved(0);
419
420	/* Clear FPU register state. */
421	t->fpsaved[0] = 0;
422}
423
424/* It's a bit more tricky when 64-bit tasks are involved... */
425static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
426{
427	bool stack_64bit = test_thread_64bit_stack(psp);
428	unsigned long fp, distance, rval;
429
430	if (stack_64bit) {
431		csp += STACK_BIAS;
432		psp += STACK_BIAS;
433		__get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
434		fp += STACK_BIAS;
435		if (test_thread_flag(TIF_32BIT))
436			fp &= 0xffffffff;
437	} else
438		__get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
439
440	/* Now align the stack as this is mandatory in the Sparc ABI
441	 * due to how register windows work.  This hides the
442	 * restriction from thread libraries etc.
443	 */
444	csp &= ~15UL;
445
446	distance = fp - psp;
447	rval = (csp - distance);
448	if (raw_copy_in_user((void __user *)rval, (void __user *)psp, distance))
449		rval = 0;
450	else if (!stack_64bit) {
451		if (put_user(((u32)csp),
452			     &(((struct reg_window32 __user *)rval)->ins[6])))
453			rval = 0;
454	} else {
455		if (put_user(((u64)csp - STACK_BIAS),
456			     &(((struct reg_window __user *)rval)->ins[6])))
457			rval = 0;
458		else
459			rval = rval - STACK_BIAS;
460	}
461
462	return rval;
463}
464
465/* Standard stuff. */
466static inline void shift_window_buffer(int first_win, int last_win,
467				       struct thread_info *t)
468{
469	int i;
470
471	for (i = first_win; i < last_win; i++) {
472		t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
473		memcpy(&t->reg_window[i], &t->reg_window[i+1],
474		       sizeof(struct reg_window));
475	}
476}
477
478void synchronize_user_stack(void)
479{
480	struct thread_info *t = current_thread_info();
481	unsigned long window;
482
483	flush_user_windows();
484	if ((window = get_thread_wsaved()) != 0) {
485		window -= 1;
486		do {
487			struct reg_window *rwin = &t->reg_window[window];
488			int winsize = sizeof(struct reg_window);
489			unsigned long sp;
490
491			sp = t->rwbuf_stkptrs[window];
492
493			if (test_thread_64bit_stack(sp))
494				sp += STACK_BIAS;
495			else
496				winsize = sizeof(struct reg_window32);
497
498			if (!copy_to_user((char __user *)sp, rwin, winsize)) {
499				shift_window_buffer(window, get_thread_wsaved() - 1, t);
500				set_thread_wsaved(get_thread_wsaved() - 1);
501			}
502		} while (window--);
503	}
504}
505
506static void stack_unaligned(unsigned long sp)
507{
508	force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *) sp);
509}
510
511static const char uwfault32[] = KERN_INFO \
512	"%s[%d]: bad register window fault: SP %08lx (orig_sp %08lx) TPC %08lx O7 %08lx\n";
513static const char uwfault64[] = KERN_INFO \
514	"%s[%d]: bad register window fault: SP %016lx (orig_sp %016lx) TPC %08lx O7 %016lx\n";
 
 
 
515
516void fault_in_user_windows(struct pt_regs *regs)
517{
518	struct thread_info *t = current_thread_info();
519	unsigned long window;
520
521	flush_user_windows();
522	window = get_thread_wsaved();
523
524	if (likely(window != 0)) {
525		window -= 1;
526		do {
527			struct reg_window *rwin = &t->reg_window[window];
528			int winsize = sizeof(struct reg_window);
529			unsigned long sp, orig_sp;
530
531			orig_sp = sp = t->rwbuf_stkptrs[window];
532
533			if (test_thread_64bit_stack(sp))
534				sp += STACK_BIAS;
535			else
536				winsize = sizeof(struct reg_window32);
537
538			if (unlikely(sp & 0x7UL))
539				stack_unaligned(sp);
540
541			if (unlikely(copy_to_user((char __user *)sp,
542						  rwin, winsize))) {
543				if (show_unhandled_signals)
544					printk_ratelimited(is_compat_task() ?
545							   uwfault32 : uwfault64,
546							   current->comm, current->pid,
547							   sp, orig_sp,
548							   regs->tpc,
549							   regs->u_regs[UREG_I7]);
550				goto barf;
551			}
552		} while (window--);
553	}
554	set_thread_wsaved(0);
555	return;
556
557barf:
558	set_thread_wsaved(window + 1);
559	force_sig(SIGSEGV);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
560}
561
562/* Copy a Sparc thread.  The fork() return value conventions
563 * under SunOS are nothing short of bletcherous:
564 * Parent -->  %o0 == childs  pid, %o1 == 0
565 * Child  -->  %o0 == parents pid, %o1 == 1
566 */
567int copy_thread(struct task_struct *p, const struct kernel_clone_args *args)
 
568{
569	unsigned long clone_flags = args->flags;
570	unsigned long sp = args->stack;
571	unsigned long tls = args->tls;
572	struct thread_info *t = task_thread_info(p);
573	struct pt_regs *regs = current_pt_regs();
574	struct sparc_stackf *parent_sf;
575	unsigned long child_stack_sz;
576	char *child_trap_frame;
577
578	/* Calculate offset to stack_frame & pt_regs */
579	child_stack_sz = (STACKFRAME_SZ + TRACEREG_SZ);
580	child_trap_frame = (task_stack_page(p) +
581			    (THREAD_SIZE - child_stack_sz));
582
583	t->new_child = 1;
584	t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
585	t->kregs = (struct pt_regs *) (child_trap_frame +
586				       sizeof(struct sparc_stackf));
587	t->fpsaved[0] = 0;
588
589	if (unlikely(args->fn)) {
590		memset(child_trap_frame, 0, child_stack_sz);
591		__thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] = 
592			(current_pt_regs()->tstate + 1) & TSTATE_CWP;
593		t->kregs->u_regs[UREG_G1] = (unsigned long) args->fn;
594		t->kregs->u_regs[UREG_G2] = (unsigned long) args->fn_arg;
 
595		return 0;
596	}
597
598	parent_sf = ((struct sparc_stackf *) regs) - 1;
599	memcpy(child_trap_frame, parent_sf, child_stack_sz);
600	if (t->flags & _TIF_32BIT) {
601		sp &= 0x00000000ffffffffUL;
602		regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
603	}
604	t->kregs->u_regs[UREG_FP] = sp;
605	__thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] = 
606		(regs->tstate + 1) & TSTATE_CWP;
 
607	if (sp != regs->u_regs[UREG_FP]) {
608		unsigned long csp;
609
610		csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
611		if (!csp)
612			return -EFAULT;
613		t->kregs->u_regs[UREG_FP] = csp;
614	}
615	if (t->utraps)
616		t->utraps[0]++;
617
618	/* Set the return value for the child. */
619	t->kregs->u_regs[UREG_I0] = current->pid;
620	t->kregs->u_regs[UREG_I1] = 1;
621
622	/* Set the second return value for the parent. */
623	regs->u_regs[UREG_I1] = 0;
624
625	if (clone_flags & CLONE_SETTLS)
626		t->kregs->u_regs[UREG_G7] = tls;
627
628	return 0;
629}
630
631/* TIF_MCDPER in thread info flags for current task is updated lazily upon
632 * a context switch. Update this flag in current task's thread flags
633 * before dup so the dup'd task will inherit the current TIF_MCDPER flag.
 
 
 
 
 
 
 
 
 
 
 
 
634 */
635int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
636{
637	if (adi_capable()) {
638		register unsigned long tmp_mcdper;
639
640		__asm__ __volatile__(
641			".word 0x83438000\n\t"	/* rd  %mcdper, %g1 */
642			"mov %%g1, %0\n\t"
643			: "=r" (tmp_mcdper)
644			:
645			: "g1");
646		if (tmp_mcdper)
647			set_thread_flag(TIF_MCDPER);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
648		else
649			clear_thread_flag(TIF_MCDPER);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
650	}
651
652	*dst = *src;
653	return 0;
654}
 
655
656unsigned long __get_wchan(struct task_struct *task)
657{
658	unsigned long pc, fp, bias = 0;
659	struct thread_info *tp;
660	struct reg_window *rw;
661        unsigned long ret = 0;
662	int count = 0; 
 
 
 
 
663
664	tp = task_thread_info(task);
665	bias = STACK_BIAS;
666	fp = task_thread_info(task)->ksp + bias;
667
668	do {
669		if (!kstack_valid(tp, fp))
670			break;
671		rw = (struct reg_window *) fp;
672		pc = rw->ins[7];
673		if (!in_sched_functions(pc)) {
674			ret = pc;
675			goto out;
676		}
677		fp = rw->ins[6] + bias;
678	} while (++count < 16);
679
680out:
681	return ret;
682}
v3.15
 
  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. */
 57void 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
 91void arch_cpu_idle_dead()
 92{
 93	sched_preempt_enable_no_resched();
 94	cpu_play_dead();
 95}
 96#endif
 97
 98#ifdef CONFIG_COMPAT
 99static 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)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
128static 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
167void 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
191union global_cpu_snapshot global_cpu_snapshot[NR_CPUS];
192static DEFINE_SPINLOCK(global_cpu_snapshot_lock);
193
194static 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 */
232static 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
242void arch_trigger_all_cpu_backtrace(void)
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	memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
255
256	this_cpu = raw_smp_processor_id();
 
 
 
257
258	__global_reg_self(tp, regs, this_cpu);
 
259
260	smp_fetch_global_regs();
 
261
262	for_each_online_cpu(cpu) {
263		struct global_reg_snapshot *gp = &global_cpu_snapshot[cpu].reg;
264
265		__global_reg_poll(gp);
266
267		tp = gp->thread;
268		printk("%c CPU[%3d]: TSTATE[%016lx] TPC[%016lx] TNPC[%016lx] TASK[%s:%d]\n",
269		       (cpu == this_cpu ? '*' : ' '), cpu,
270		       gp->tstate, gp->tpc, gp->tnpc,
271		       ((tp && tp->task) ? tp->task->comm : "NULL"),
272		       ((tp && tp->task) ? tp->task->pid : -1));
273
274		if (gp->tstate & TSTATE_PRIV) {
275			printk("             TPC[%pS] O7[%pS] I7[%pS] RPC[%pS]\n",
276			       (void *) gp->tpc,
277			       (void *) gp->o7,
278			       (void *) gp->i7,
279			       (void *) gp->rpc);
280		} else {
281			printk("             TPC[%lx] O7[%lx] I7[%lx] RPC[%lx]\n",
282			       gp->tpc, gp->o7, gp->i7, gp->rpc);
283		}
 
 
284	}
285
286	memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
287
288	spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags);
289}
290
291#ifdef CONFIG_MAGIC_SYSRQ
292
293static void sysrq_handle_globreg(int key)
294{
295	arch_trigger_all_cpu_backtrace();
296}
297
298static struct sysrq_key_op sparc_globalreg_op = {
299	.handler	= sysrq_handle_globreg,
300	.help_msg	= "global-regs(y)",
301	.action_msg	= "Show Global CPU Regs",
302};
303
304static void __global_pmu_self(int this_cpu)
305{
306	struct global_pmu_snapshot *pp;
307	int i, num;
308
 
 
 
309	pp = &global_cpu_snapshot[this_cpu].pmu;
310
311	num = 1;
312	if (tlb_type == hypervisor &&
313	    sun4v_chip_type >= SUN4V_CHIP_NIAGARA4)
314		num = 4;
315
316	for (i = 0; i < num; i++) {
317		pp->pcr[i] = pcr_ops->read_pcr(i);
318		pp->pic[i] = pcr_ops->read_pic(i);
319	}
320}
321
322static void __global_pmu_poll(struct global_pmu_snapshot *pp)
323{
324	int limit = 0;
325
326	while (!pp->pcr[0] && ++limit < 100) {
327		barrier();
328		udelay(1);
329	}
330}
331
332static void pmu_snapshot_all_cpus(void)
333{
334	unsigned long flags;
335	int this_cpu, cpu;
336
337	spin_lock_irqsave(&global_cpu_snapshot_lock, flags);
338
339	memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
340
341	this_cpu = raw_smp_processor_id();
342
343	__global_pmu_self(this_cpu);
344
345	smp_fetch_global_pmu();
346
347	for_each_online_cpu(cpu) {
348		struct global_pmu_snapshot *pp = &global_cpu_snapshot[cpu].pmu;
349
350		__global_pmu_poll(pp);
351
352		printk("%c CPU[%3d]: PCR[%08lx:%08lx:%08lx:%08lx] PIC[%08lx:%08lx:%08lx:%08lx]\n",
353		       (cpu == this_cpu ? '*' : ' '), cpu,
354		       pp->pcr[0], pp->pcr[1], pp->pcr[2], pp->pcr[3],
355		       pp->pic[0], pp->pic[1], pp->pic[2], pp->pic[3]);
 
 
356	}
357
358	memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
359
360	spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags);
361}
362
363static void sysrq_handle_globpmu(int key)
364{
365	pmu_snapshot_all_cpus();
366}
367
368static struct sysrq_key_op sparc_globalpmu_op = {
369	.handler	= sysrq_handle_globpmu,
370	.help_msg	= "global-pmu(x)",
371	.action_msg	= "Show Global PMU Regs",
372};
373
374static int __init sparc_sysrq_init(void)
375{
376	int ret = register_sysrq_key('y', &sparc_globalreg_op);
377
378	if (!ret)
379		ret = register_sysrq_key('x', &sparc_globalpmu_op);
380	return ret;
381}
382
383core_initcall(sparc_sysrq_init);
384
385#endif
386
387unsigned long thread_saved_pc(struct task_struct *tsk)
388{
389	struct thread_info *ti = task_thread_info(tsk);
390	unsigned long ret = 0xdeadbeefUL;
391	
392	if (ti && ti->ksp) {
393		unsigned long *sp;
394		sp = (unsigned long *)(ti->ksp + STACK_BIAS);
395		if (((unsigned long)sp & (sizeof(long) - 1)) == 0UL &&
396		    sp[14]) {
397			unsigned long *fp;
398			fp = (unsigned long *)(sp[14] + STACK_BIAS);
399			if (((unsigned long)fp & (sizeof(long) - 1)) == 0UL)
400				ret = fp[15];
401		}
402	}
403	return ret;
404}
405
406/* Free current thread data structures etc.. */
407void exit_thread(void)
408{
409	struct thread_info *t = current_thread_info();
410
411	if (t->utraps) {
412		if (t->utraps[0] < 2)
413			kfree (t->utraps);
414		else
415			t->utraps[0]--;
416	}
417}
418
419void flush_thread(void)
420{
421	struct thread_info *t = current_thread_info();
422	struct mm_struct *mm;
423
424	mm = t->task->mm;
425	if (mm)
426		tsb_context_switch(mm);
427
428	set_thread_wsaved(0);
429
430	/* Clear FPU register state. */
431	t->fpsaved[0] = 0;
432}
433
434/* It's a bit more tricky when 64-bit tasks are involved... */
435static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
436{
437	bool stack_64bit = test_thread_64bit_stack(psp);
438	unsigned long fp, distance, rval;
439
440	if (stack_64bit) {
441		csp += STACK_BIAS;
442		psp += STACK_BIAS;
443		__get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
444		fp += STACK_BIAS;
445		if (test_thread_flag(TIF_32BIT))
446			fp &= 0xffffffff;
447	} else
448		__get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
449
450	/* Now align the stack as this is mandatory in the Sparc ABI
451	 * due to how register windows work.  This hides the
452	 * restriction from thread libraries etc.
453	 */
454	csp &= ~15UL;
455
456	distance = fp - psp;
457	rval = (csp - distance);
458	if (copy_in_user((void __user *) rval, (void __user *) psp, distance))
459		rval = 0;
460	else if (!stack_64bit) {
461		if (put_user(((u32)csp),
462			     &(((struct reg_window32 __user *)rval)->ins[6])))
463			rval = 0;
464	} else {
465		if (put_user(((u64)csp - STACK_BIAS),
466			     &(((struct reg_window __user *)rval)->ins[6])))
467			rval = 0;
468		else
469			rval = rval - STACK_BIAS;
470	}
471
472	return rval;
473}
474
475/* Standard stuff. */
476static inline void shift_window_buffer(int first_win, int last_win,
477				       struct thread_info *t)
478{
479	int i;
480
481	for (i = first_win; i < last_win; i++) {
482		t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
483		memcpy(&t->reg_window[i], &t->reg_window[i+1],
484		       sizeof(struct reg_window));
485	}
486}
487
488void synchronize_user_stack(void)
489{
490	struct thread_info *t = current_thread_info();
491	unsigned long window;
492
493	flush_user_windows();
494	if ((window = get_thread_wsaved()) != 0) {
495		window -= 1;
496		do {
497			struct reg_window *rwin = &t->reg_window[window];
498			int winsize = sizeof(struct reg_window);
499			unsigned long sp;
500
501			sp = t->rwbuf_stkptrs[window];
502
503			if (test_thread_64bit_stack(sp))
504				sp += STACK_BIAS;
505			else
506				winsize = sizeof(struct reg_window32);
507
508			if (!copy_to_user((char __user *)sp, rwin, winsize)) {
509				shift_window_buffer(window, get_thread_wsaved() - 1, t);
510				set_thread_wsaved(get_thread_wsaved() - 1);
511			}
512		} while (window--);
513	}
514}
515
516static void stack_unaligned(unsigned long sp)
517{
518	siginfo_t info;
 
519
520	info.si_signo = SIGBUS;
521	info.si_errno = 0;
522	info.si_code = BUS_ADRALN;
523	info.si_addr = (void __user *) sp;
524	info.si_trapno = 0;
525	force_sig_info(SIGBUS, &info, current);
526}
527
528void fault_in_user_windows(void)
529{
530	struct thread_info *t = current_thread_info();
531	unsigned long window;
532
533	flush_user_windows();
534	window = get_thread_wsaved();
535
536	if (likely(window != 0)) {
537		window -= 1;
538		do {
539			struct reg_window *rwin = &t->reg_window[window];
540			int winsize = sizeof(struct reg_window);
541			unsigned long sp;
542
543			sp = t->rwbuf_stkptrs[window];
544
545			if (test_thread_64bit_stack(sp))
546				sp += STACK_BIAS;
547			else
548				winsize = sizeof(struct reg_window32);
549
550			if (unlikely(sp & 0x7UL))
551				stack_unaligned(sp);
552
553			if (unlikely(copy_to_user((char __user *)sp,
554						  rwin, winsize)))
 
 
 
 
 
 
 
555				goto barf;
 
556		} while (window--);
557	}
558	set_thread_wsaved(0);
559	return;
560
561barf:
562	set_thread_wsaved(window + 1);
563	user_exit();
564	do_exit(SIGILL);
565}
566
567asmlinkage long sparc_do_fork(unsigned long clone_flags,
568			      unsigned long stack_start,
569			      struct pt_regs *regs,
570			      unsigned long stack_size)
571{
572	int __user *parent_tid_ptr, *child_tid_ptr;
573	unsigned long orig_i1 = regs->u_regs[UREG_I1];
574	long ret;
575
576#ifdef CONFIG_COMPAT
577	if (test_thread_flag(TIF_32BIT)) {
578		parent_tid_ptr = compat_ptr(regs->u_regs[UREG_I2]);
579		child_tid_ptr = compat_ptr(regs->u_regs[UREG_I4]);
580	} else
581#endif
582	{
583		parent_tid_ptr = (int __user *) regs->u_regs[UREG_I2];
584		child_tid_ptr = (int __user *) regs->u_regs[UREG_I4];
585	}
586
587	ret = do_fork(clone_flags, stack_start, stack_size,
588		      parent_tid_ptr, child_tid_ptr);
589
590	/* If we get an error and potentially restart the system
591	 * call, we're screwed because copy_thread() clobbered
592	 * the parent's %o1.  So detect that case and restore it
593	 * here.
594	 */
595	if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
596		regs->u_regs[UREG_I1] = orig_i1;
597
598	return ret;
599}
600
601/* Copy a Sparc thread.  The fork() return value conventions
602 * under SunOS are nothing short of bletcherous:
603 * Parent -->  %o0 == childs  pid, %o1 == 0
604 * Child  -->  %o0 == parents pid, %o1 == 1
605 */
606int copy_thread(unsigned long clone_flags, unsigned long sp,
607		unsigned long arg, struct task_struct *p)
608{
 
 
 
609	struct thread_info *t = task_thread_info(p);
610	struct pt_regs *regs = current_pt_regs();
611	struct sparc_stackf *parent_sf;
612	unsigned long child_stack_sz;
613	char *child_trap_frame;
614
615	/* Calculate offset to stack_frame & pt_regs */
616	child_stack_sz = (STACKFRAME_SZ + TRACEREG_SZ);
617	child_trap_frame = (task_stack_page(p) +
618			    (THREAD_SIZE - child_stack_sz));
619
620	t->new_child = 1;
621	t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
622	t->kregs = (struct pt_regs *) (child_trap_frame +
623				       sizeof(struct sparc_stackf));
624	t->fpsaved[0] = 0;
625
626	if (unlikely(p->flags & PF_KTHREAD)) {
627		memset(child_trap_frame, 0, child_stack_sz);
628		__thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] = 
629			(current_pt_regs()->tstate + 1) & TSTATE_CWP;
630		t->current_ds = ASI_P;
631		t->kregs->u_regs[UREG_G1] = sp; /* function */
632		t->kregs->u_regs[UREG_G2] = arg;
633		return 0;
634	}
635
636	parent_sf = ((struct sparc_stackf *) regs) - 1;
637	memcpy(child_trap_frame, parent_sf, child_stack_sz);
638	if (t->flags & _TIF_32BIT) {
639		sp &= 0x00000000ffffffffUL;
640		regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
641	}
642	t->kregs->u_regs[UREG_FP] = sp;
643	__thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] = 
644		(regs->tstate + 1) & TSTATE_CWP;
645	t->current_ds = ASI_AIUS;
646	if (sp != regs->u_regs[UREG_FP]) {
647		unsigned long csp;
648
649		csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
650		if (!csp)
651			return -EFAULT;
652		t->kregs->u_regs[UREG_FP] = csp;
653	}
654	if (t->utraps)
655		t->utraps[0]++;
656
657	/* Set the return value for the child. */
658	t->kregs->u_regs[UREG_I0] = current->pid;
659	t->kregs->u_regs[UREG_I1] = 1;
660
661	/* Set the second return value for the parent. */
662	regs->u_regs[UREG_I1] = 0;
663
664	if (clone_flags & CLONE_SETTLS)
665		t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
666
667	return 0;
668}
669
670typedef struct {
671	union {
672		unsigned int	pr_regs[32];
673		unsigned long	pr_dregs[16];
674	} pr_fr;
675	unsigned int __unused;
676	unsigned int	pr_fsr;
677	unsigned char	pr_qcnt;
678	unsigned char	pr_q_entrysize;
679	unsigned char	pr_en;
680	unsigned int	pr_q[64];
681} elf_fpregset_t32;
682
683/*
684 * fill in the fpu structure for a core dump.
685 */
686int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
687{
688	unsigned long *kfpregs = current_thread_info()->fpregs;
689	unsigned long fprs = current_thread_info()->fpsaved[0];
690
691	if (test_thread_flag(TIF_32BIT)) {
692		elf_fpregset_t32 *fpregs32 = (elf_fpregset_t32 *)fpregs;
693
694		if (fprs & FPRS_DL)
695			memcpy(&fpregs32->pr_fr.pr_regs[0], kfpregs,
696			       sizeof(unsigned int) * 32);
697		else
698			memset(&fpregs32->pr_fr.pr_regs[0], 0,
699			       sizeof(unsigned int) * 32);
700		fpregs32->pr_qcnt = 0;
701		fpregs32->pr_q_entrysize = 8;
702		memset(&fpregs32->pr_q[0], 0,
703		       (sizeof(unsigned int) * 64));
704		if (fprs & FPRS_FEF) {
705			fpregs32->pr_fsr = (unsigned int) current_thread_info()->xfsr[0];
706			fpregs32->pr_en = 1;
707		} else {
708			fpregs32->pr_fsr = 0;
709			fpregs32->pr_en = 0;
710		}
711	} else {
712		if(fprs & FPRS_DL)
713			memcpy(&fpregs->pr_regs[0], kfpregs,
714			       sizeof(unsigned int) * 32);
715		else
716			memset(&fpregs->pr_regs[0], 0,
717			       sizeof(unsigned int) * 32);
718		if(fprs & FPRS_DU)
719			memcpy(&fpregs->pr_regs[16], kfpregs+16,
720			       sizeof(unsigned int) * 32);
721		else
722			memset(&fpregs->pr_regs[16], 0,
723			       sizeof(unsigned int) * 32);
724		if(fprs & FPRS_FEF) {
725			fpregs->pr_fsr = current_thread_info()->xfsr[0];
726			fpregs->pr_gsr = current_thread_info()->gsr[0];
727		} else {
728			fpregs->pr_fsr = fpregs->pr_gsr = 0;
729		}
730		fpregs->pr_fprs = fprs;
731	}
732	return 1;
 
 
733}
734EXPORT_SYMBOL(dump_fpu);
735
736unsigned long get_wchan(struct task_struct *task)
737{
738	unsigned long pc, fp, bias = 0;
739	struct thread_info *tp;
740	struct reg_window *rw;
741        unsigned long ret = 0;
742	int count = 0; 
743
744	if (!task || task == current ||
745            task->state == TASK_RUNNING)
746		goto out;
747
748	tp = task_thread_info(task);
749	bias = STACK_BIAS;
750	fp = task_thread_info(task)->ksp + bias;
751
752	do {
753		if (!kstack_valid(tp, fp))
754			break;
755		rw = (struct reg_window *) fp;
756		pc = rw->ins[7];
757		if (!in_sched_functions(pc)) {
758			ret = pc;
759			goto out;
760		}
761		fp = rw->ins[6] + bias;
762	} while (++count < 16);
763
764out:
765	return ret;
766}