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v4.17
  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
 13#include <stdarg.h>
 14
 15#include <linux/errno.h>
 16#include <linux/export.h>
 17#include <linux/sched.h>
 18#include <linux/sched/debug.h>
 19#include <linux/sched/task.h>
 20#include <linux/sched/task_stack.h>
 21#include <linux/kernel.h>
 22#include <linux/mm.h>
 23#include <linux/fs.h>
 24#include <linux/smp.h>
 25#include <linux/stddef.h>
 26#include <linux/ptrace.h>
 27#include <linux/slab.h>
 28#include <linux/user.h>
 29#include <linux/delay.h>
 30#include <linux/compat.h>
 31#include <linux/tick.h>
 32#include <linux/init.h>
 33#include <linux/cpu.h>
 34#include <linux/perf_event.h>
 35#include <linux/elfcore.h>
 36#include <linux/sysrq.h>
 37#include <linux/nmi.h>
 38#include <linux/context_tracking.h>
 
 39
 40#include <linux/uaccess.h>
 41#include <asm/page.h>
 42#include <asm/pgalloc.h>
 43#include <asm/pgtable.h>
 44#include <asm/processor.h>
 45#include <asm/pstate.h>
 46#include <asm/elf.h>
 47#include <asm/fpumacro.h>
 48#include <asm/head.h>
 49#include <asm/cpudata.h>
 50#include <asm/mmu_context.h>
 51#include <asm/unistd.h>
 52#include <asm/hypervisor.h>
 53#include <asm/syscalls.h>
 54#include <asm/irq_regs.h>
 55#include <asm/smp.h>
 56#include <asm/pcr.h>
 57
 58#include "kstack.h"
 59
 60/* Idle loop support on sparc64. */
 61void arch_cpu_idle(void)
 62{
 63	if (tlb_type != hypervisor) {
 64		touch_nmi_watchdog();
 65		local_irq_enable();
 66	} else {
 67		unsigned long pstate;
 68
 69		local_irq_enable();
 70
 71                /* The sun4v sleeping code requires that we have PSTATE.IE cleared over
 72                 * the cpu sleep hypervisor call.
 73                 */
 74		__asm__ __volatile__(
 75			"rdpr %%pstate, %0\n\t"
 76			"andn %0, %1, %0\n\t"
 77			"wrpr %0, %%g0, %%pstate"
 78			: "=&r" (pstate)
 79			: "i" (PSTATE_IE));
 80
 81		if (!need_resched() && !cpu_is_offline(smp_processor_id())) {
 82			sun4v_cpu_yield();
 83			/* If resumed by cpu_poke then we need to explicitly
 84			 * call scheduler_ipi().
 85			 */
 86			scheduler_poke();
 87		}
 88
 89		/* Re-enable interrupts. */
 90		__asm__ __volatile__(
 91			"rdpr %%pstate, %0\n\t"
 92			"or %0, %1, %0\n\t"
 93			"wrpr %0, %%g0, %%pstate"
 94			: "=&r" (pstate)
 95			: "i" (PSTATE_IE));
 96	}
 97}
 98
 99#ifdef CONFIG_HOTPLUG_CPU
100void arch_cpu_idle_dead(void)
101{
102	sched_preempt_enable_no_resched();
103	cpu_play_dead();
104}
105#endif
106
107#ifdef CONFIG_COMPAT
108static void show_regwindow32(struct pt_regs *regs)
109{
110	struct reg_window32 __user *rw;
111	struct reg_window32 r_w;
112	mm_segment_t old_fs;
113	
114	__asm__ __volatile__ ("flushw");
115	rw = compat_ptr((unsigned int)regs->u_regs[14]);
116	old_fs = get_fs();
117	set_fs (USER_DS);
118	if (copy_from_user (&r_w, rw, sizeof(r_w))) {
119		set_fs (old_fs);
120		return;
121	}
122
123	set_fs (old_fs);			
124	printk("l0: %08x l1: %08x l2: %08x l3: %08x "
125	       "l4: %08x l5: %08x l6: %08x l7: %08x\n",
126	       r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
127	       r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
128	printk("i0: %08x i1: %08x i2: %08x i3: %08x "
129	       "i4: %08x i5: %08x i6: %08x i7: %08x\n",
130	       r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
131	       r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
132}
133#else
134#define show_regwindow32(regs)	do { } while (0)
135#endif
136
137static void show_regwindow(struct pt_regs *regs)
138{
139	struct reg_window __user *rw;
140	struct reg_window *rwk;
141	struct reg_window r_w;
142	mm_segment_t old_fs;
143
144	if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
145		__asm__ __volatile__ ("flushw");
146		rw = (struct reg_window __user *)
147			(regs->u_regs[14] + STACK_BIAS);
148		rwk = (struct reg_window *)
149			(regs->u_regs[14] + STACK_BIAS);
150		if (!(regs->tstate & TSTATE_PRIV)) {
151			old_fs = get_fs();
152			set_fs (USER_DS);
153			if (copy_from_user (&r_w, rw, sizeof(r_w))) {
154				set_fs (old_fs);
155				return;
156			}
157			rwk = &r_w;
158			set_fs (old_fs);			
159		}
160	} else {
161		show_regwindow32(regs);
162		return;
163	}
164	printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
165	       rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
166	printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
167	       rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
168	printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
169	       rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
170	printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
171	       rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
172	if (regs->tstate & TSTATE_PRIV)
173		printk("I7: <%pS>\n", (void *) rwk->ins[7]);
174}
175
176void show_regs(struct pt_regs *regs)
177{
178	show_regs_print_info(KERN_DEFAULT);
179
180	printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x    %s\n", regs->tstate,
181	       regs->tpc, regs->tnpc, regs->y, print_tainted());
182	printk("TPC: <%pS>\n", (void *) regs->tpc);
183	printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
184	       regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
185	       regs->u_regs[3]);
186	printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
187	       regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
188	       regs->u_regs[7]);
189	printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
190	       regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
191	       regs->u_regs[11]);
192	printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
193	       regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
194	       regs->u_regs[15]);
195	printk("RPC: <%pS>\n", (void *) regs->u_regs[15]);
196	show_regwindow(regs);
197	show_stack(current, (unsigned long *) regs->u_regs[UREG_FP]);
198}
199
200union global_cpu_snapshot global_cpu_snapshot[NR_CPUS];
201static DEFINE_SPINLOCK(global_cpu_snapshot_lock);
202
203static void __global_reg_self(struct thread_info *tp, struct pt_regs *regs,
204			      int this_cpu)
205{
206	struct global_reg_snapshot *rp;
207
208	flushw_all();
209
210	rp = &global_cpu_snapshot[this_cpu].reg;
211
212	rp->tstate = regs->tstate;
213	rp->tpc = regs->tpc;
214	rp->tnpc = regs->tnpc;
215	rp->o7 = regs->u_regs[UREG_I7];
216
217	if (regs->tstate & TSTATE_PRIV) {
218		struct reg_window *rw;
219
220		rw = (struct reg_window *)
221			(regs->u_regs[UREG_FP] + STACK_BIAS);
222		if (kstack_valid(tp, (unsigned long) rw)) {
223			rp->i7 = rw->ins[7];
224			rw = (struct reg_window *)
225				(rw->ins[6] + STACK_BIAS);
226			if (kstack_valid(tp, (unsigned long) rw))
227				rp->rpc = rw->ins[7];
228		}
229	} else {
230		rp->i7 = 0;
231		rp->rpc = 0;
232	}
233	rp->thread = tp;
234}
235
236/* In order to avoid hangs we do not try to synchronize with the
237 * global register dump client cpus.  The last store they make is to
238 * the thread pointer, so do a short poll waiting for that to become
239 * non-NULL.
240 */
241static void __global_reg_poll(struct global_reg_snapshot *gp)
242{
243	int limit = 0;
244
245	while (!gp->thread && ++limit < 100) {
246		barrier();
247		udelay(1);
248	}
249}
250
251void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
252{
253	struct thread_info *tp = current_thread_info();
254	struct pt_regs *regs = get_irq_regs();
255	unsigned long flags;
256	int this_cpu, cpu;
257
258	if (!regs)
259		regs = tp->kregs;
260
261	spin_lock_irqsave(&global_cpu_snapshot_lock, flags);
262
263	this_cpu = raw_smp_processor_id();
264
265	memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
266
267	if (cpumask_test_cpu(this_cpu, mask) && !exclude_self)
268		__global_reg_self(tp, regs, this_cpu);
269
270	smp_fetch_global_regs();
271
272	for_each_cpu(cpu, mask) {
273		struct global_reg_snapshot *gp;
274
275		if (exclude_self && cpu == this_cpu)
276			continue;
277
278		gp = &global_cpu_snapshot[cpu].reg;
279
280		__global_reg_poll(gp);
281
282		tp = gp->thread;
283		printk("%c CPU[%3d]: TSTATE[%016lx] TPC[%016lx] TNPC[%016lx] TASK[%s:%d]\n",
284		       (cpu == this_cpu ? '*' : ' '), cpu,
285		       gp->tstate, gp->tpc, gp->tnpc,
286		       ((tp && tp->task) ? tp->task->comm : "NULL"),
287		       ((tp && tp->task) ? tp->task->pid : -1));
288
289		if (gp->tstate & TSTATE_PRIV) {
290			printk("             TPC[%pS] O7[%pS] I7[%pS] RPC[%pS]\n",
291			       (void *) gp->tpc,
292			       (void *) gp->o7,
293			       (void *) gp->i7,
294			       (void *) gp->rpc);
295		} else {
296			printk("             TPC[%lx] O7[%lx] I7[%lx] RPC[%lx]\n",
297			       gp->tpc, gp->o7, gp->i7, gp->rpc);
298		}
299
300		touch_nmi_watchdog();
301	}
302
303	memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
304
305	spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags);
306}
307
308#ifdef CONFIG_MAGIC_SYSRQ
309
310static void sysrq_handle_globreg(int key)
311{
312	trigger_all_cpu_backtrace();
313}
314
315static struct sysrq_key_op sparc_globalreg_op = {
316	.handler	= sysrq_handle_globreg,
317	.help_msg	= "global-regs(y)",
318	.action_msg	= "Show Global CPU Regs",
319};
320
321static void __global_pmu_self(int this_cpu)
322{
323	struct global_pmu_snapshot *pp;
324	int i, num;
325
326	if (!pcr_ops)
327		return;
328
329	pp = &global_cpu_snapshot[this_cpu].pmu;
330
331	num = 1;
332	if (tlb_type == hypervisor &&
333	    sun4v_chip_type >= SUN4V_CHIP_NIAGARA4)
334		num = 4;
335
336	for (i = 0; i < num; i++) {
337		pp->pcr[i] = pcr_ops->read_pcr(i);
338		pp->pic[i] = pcr_ops->read_pic(i);
339	}
340}
341
342static void __global_pmu_poll(struct global_pmu_snapshot *pp)
343{
344	int limit = 0;
345
346	while (!pp->pcr[0] && ++limit < 100) {
347		barrier();
348		udelay(1);
349	}
350}
351
352static void pmu_snapshot_all_cpus(void)
353{
354	unsigned long flags;
355	int this_cpu, cpu;
356
357	spin_lock_irqsave(&global_cpu_snapshot_lock, flags);
358
359	memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
360
361	this_cpu = raw_smp_processor_id();
362
363	__global_pmu_self(this_cpu);
364
365	smp_fetch_global_pmu();
366
367	for_each_online_cpu(cpu) {
368		struct global_pmu_snapshot *pp = &global_cpu_snapshot[cpu].pmu;
369
370		__global_pmu_poll(pp);
371
372		printk("%c CPU[%3d]: PCR[%08lx:%08lx:%08lx:%08lx] PIC[%08lx:%08lx:%08lx:%08lx]\n",
373		       (cpu == this_cpu ? '*' : ' '), cpu,
374		       pp->pcr[0], pp->pcr[1], pp->pcr[2], pp->pcr[3],
375		       pp->pic[0], pp->pic[1], pp->pic[2], pp->pic[3]);
376
377		touch_nmi_watchdog();
378	}
379
380	memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
381
382	spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags);
383}
384
385static void sysrq_handle_globpmu(int key)
386{
387	pmu_snapshot_all_cpus();
388}
389
390static struct sysrq_key_op sparc_globalpmu_op = {
391	.handler	= sysrq_handle_globpmu,
392	.help_msg	= "global-pmu(x)",
393	.action_msg	= "Show Global PMU Regs",
394};
395
396static int __init sparc_sysrq_init(void)
397{
398	int ret = register_sysrq_key('y', &sparc_globalreg_op);
399
400	if (!ret)
401		ret = register_sysrq_key('x', &sparc_globalpmu_op);
402	return ret;
403}
404
405core_initcall(sparc_sysrq_init);
406
407#endif
408
409/* Free current thread data structures etc.. */
410void exit_thread(struct task_struct *tsk)
411{
412	struct thread_info *t = task_thread_info(tsk);
413
414	if (t->utraps) {
415		if (t->utraps[0] < 2)
416			kfree (t->utraps);
417		else
418			t->utraps[0]--;
419	}
420}
421
422void flush_thread(void)
423{
424	struct thread_info *t = current_thread_info();
425	struct mm_struct *mm;
426
427	mm = t->task->mm;
428	if (mm)
429		tsb_context_switch(mm);
430
431	set_thread_wsaved(0);
432
433	/* Clear FPU register state. */
434	t->fpsaved[0] = 0;
435}
436
437/* It's a bit more tricky when 64-bit tasks are involved... */
438static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
439{
440	bool stack_64bit = test_thread_64bit_stack(psp);
441	unsigned long fp, distance, rval;
442
443	if (stack_64bit) {
444		csp += STACK_BIAS;
445		psp += STACK_BIAS;
446		__get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
447		fp += STACK_BIAS;
448		if (test_thread_flag(TIF_32BIT))
449			fp &= 0xffffffff;
450	} else
451		__get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
452
453	/* Now align the stack as this is mandatory in the Sparc ABI
454	 * due to how register windows work.  This hides the
455	 * restriction from thread libraries etc.
456	 */
457	csp &= ~15UL;
458
459	distance = fp - psp;
460	rval = (csp - distance);
461	if (copy_in_user((void __user *) rval, (void __user *) psp, distance))
462		rval = 0;
463	else if (!stack_64bit) {
464		if (put_user(((u32)csp),
465			     &(((struct reg_window32 __user *)rval)->ins[6])))
466			rval = 0;
467	} else {
468		if (put_user(((u64)csp - STACK_BIAS),
469			     &(((struct reg_window __user *)rval)->ins[6])))
470			rval = 0;
471		else
472			rval = rval - STACK_BIAS;
473	}
474
475	return rval;
476}
477
478/* Standard stuff. */
479static inline void shift_window_buffer(int first_win, int last_win,
480				       struct thread_info *t)
481{
482	int i;
483
484	for (i = first_win; i < last_win; i++) {
485		t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
486		memcpy(&t->reg_window[i], &t->reg_window[i+1],
487		       sizeof(struct reg_window));
488	}
489}
490
491void synchronize_user_stack(void)
492{
493	struct thread_info *t = current_thread_info();
494	unsigned long window;
495
496	flush_user_windows();
497	if ((window = get_thread_wsaved()) != 0) {
498		window -= 1;
499		do {
500			struct reg_window *rwin = &t->reg_window[window];
501			int winsize = sizeof(struct reg_window);
502			unsigned long sp;
503
504			sp = t->rwbuf_stkptrs[window];
505
506			if (test_thread_64bit_stack(sp))
507				sp += STACK_BIAS;
508			else
509				winsize = sizeof(struct reg_window32);
510
511			if (!copy_to_user((char __user *)sp, rwin, winsize)) {
512				shift_window_buffer(window, get_thread_wsaved() - 1, t);
513				set_thread_wsaved(get_thread_wsaved() - 1);
514			}
515		} while (window--);
516	}
517}
518
519static void stack_unaligned(unsigned long sp)
520{
521	siginfo_t info;
522
523	info.si_signo = SIGBUS;
524	info.si_errno = 0;
525	info.si_code = BUS_ADRALN;
526	info.si_addr = (void __user *) sp;
527	info.si_trapno = 0;
528	force_sig_info(SIGBUS, &info, current);
529}
530
531void fault_in_user_windows(void)
 
 
 
 
 
532{
533	struct thread_info *t = current_thread_info();
534	unsigned long window;
535
536	flush_user_windows();
537	window = get_thread_wsaved();
538
539	if (likely(window != 0)) {
540		window -= 1;
541		do {
542			struct reg_window *rwin = &t->reg_window[window];
543			int winsize = sizeof(struct reg_window);
544			unsigned long sp;
545
546			sp = t->rwbuf_stkptrs[window];
547
548			if (test_thread_64bit_stack(sp))
549				sp += STACK_BIAS;
550			else
551				winsize = sizeof(struct reg_window32);
552
553			if (unlikely(sp & 0x7UL))
554				stack_unaligned(sp);
555
556			if (unlikely(copy_to_user((char __user *)sp,
557						  rwin, winsize)))
 
 
 
 
 
 
 
558				goto barf;
 
559		} while (window--);
560	}
561	set_thread_wsaved(0);
562	return;
563
564barf:
565	set_thread_wsaved(window + 1);
566	user_exit();
567	do_exit(SIGILL);
568}
569
570asmlinkage long sparc_do_fork(unsigned long clone_flags,
571			      unsigned long stack_start,
572			      struct pt_regs *regs,
573			      unsigned long stack_size)
574{
575	int __user *parent_tid_ptr, *child_tid_ptr;
576	unsigned long orig_i1 = regs->u_regs[UREG_I1];
577	long ret;
578
579#ifdef CONFIG_COMPAT
580	if (test_thread_flag(TIF_32BIT)) {
581		parent_tid_ptr = compat_ptr(regs->u_regs[UREG_I2]);
582		child_tid_ptr = compat_ptr(regs->u_regs[UREG_I4]);
583	} else
584#endif
585	{
586		parent_tid_ptr = (int __user *) regs->u_regs[UREG_I2];
587		child_tid_ptr = (int __user *) regs->u_regs[UREG_I4];
588	}
589
590	ret = do_fork(clone_flags, stack_start, stack_size,
591		      parent_tid_ptr, child_tid_ptr);
592
593	/* If we get an error and potentially restart the system
594	 * call, we're screwed because copy_thread() clobbered
595	 * the parent's %o1.  So detect that case and restore it
596	 * here.
597	 */
598	if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
599		regs->u_regs[UREG_I1] = orig_i1;
600
601	return ret;
602}
603
604/* Copy a Sparc thread.  The fork() return value conventions
605 * under SunOS are nothing short of bletcherous:
606 * Parent -->  %o0 == childs  pid, %o1 == 0
607 * Child  -->  %o0 == parents pid, %o1 == 1
608 */
609int copy_thread(unsigned long clone_flags, unsigned long sp,
610		unsigned long arg, struct task_struct *p)
611{
612	struct thread_info *t = task_thread_info(p);
613	struct pt_regs *regs = current_pt_regs();
614	struct sparc_stackf *parent_sf;
615	unsigned long child_stack_sz;
616	char *child_trap_frame;
617
618	/* Calculate offset to stack_frame & pt_regs */
619	child_stack_sz = (STACKFRAME_SZ + TRACEREG_SZ);
620	child_trap_frame = (task_stack_page(p) +
621			    (THREAD_SIZE - child_stack_sz));
622
623	t->new_child = 1;
624	t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
625	t->kregs = (struct pt_regs *) (child_trap_frame +
626				       sizeof(struct sparc_stackf));
627	t->fpsaved[0] = 0;
628
629	if (unlikely(p->flags & PF_KTHREAD)) {
630		memset(child_trap_frame, 0, child_stack_sz);
631		__thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] = 
632			(current_pt_regs()->tstate + 1) & TSTATE_CWP;
633		t->current_ds = ASI_P;
634		t->kregs->u_regs[UREG_G1] = sp; /* function */
635		t->kregs->u_regs[UREG_G2] = arg;
636		return 0;
637	}
638
639	parent_sf = ((struct sparc_stackf *) regs) - 1;
640	memcpy(child_trap_frame, parent_sf, child_stack_sz);
641	if (t->flags & _TIF_32BIT) {
642		sp &= 0x00000000ffffffffUL;
643		regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
644	}
645	t->kregs->u_regs[UREG_FP] = sp;
646	__thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] = 
647		(regs->tstate + 1) & TSTATE_CWP;
648	t->current_ds = ASI_AIUS;
649	if (sp != regs->u_regs[UREG_FP]) {
650		unsigned long csp;
651
652		csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
653		if (!csp)
654			return -EFAULT;
655		t->kregs->u_regs[UREG_FP] = csp;
656	}
657	if (t->utraps)
658		t->utraps[0]++;
659
660	/* Set the return value for the child. */
661	t->kregs->u_regs[UREG_I0] = current->pid;
662	t->kregs->u_regs[UREG_I1] = 1;
663
664	/* Set the second return value for the parent. */
665	regs->u_regs[UREG_I1] = 0;
666
667	if (clone_flags & CLONE_SETTLS)
668		t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
669
670	return 0;
671}
672
673/* TIF_MCDPER in thread info flags for current task is updated lazily upon
674 * a context switch. Update this flag in current task's thread flags
675 * before dup so the dup'd task will inherit the current TIF_MCDPER flag.
676 */
677int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
678{
679	if (adi_capable()) {
680		register unsigned long tmp_mcdper;
681
682		__asm__ __volatile__(
683			".word 0x83438000\n\t"	/* rd  %mcdper, %g1 */
684			"mov %%g1, %0\n\t"
685			: "=r" (tmp_mcdper)
686			:
687			: "g1");
688		if (tmp_mcdper)
689			set_thread_flag(TIF_MCDPER);
690		else
691			clear_thread_flag(TIF_MCDPER);
692	}
693
694	*dst = *src;
695	return 0;
696}
697
698typedef struct {
699	union {
700		unsigned int	pr_regs[32];
701		unsigned long	pr_dregs[16];
702	} pr_fr;
703	unsigned int __unused;
704	unsigned int	pr_fsr;
705	unsigned char	pr_qcnt;
706	unsigned char	pr_q_entrysize;
707	unsigned char	pr_en;
708	unsigned int	pr_q[64];
709} elf_fpregset_t32;
710
711/*
712 * fill in the fpu structure for a core dump.
713 */
714int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
715{
716	unsigned long *kfpregs = current_thread_info()->fpregs;
717	unsigned long fprs = current_thread_info()->fpsaved[0];
718
719	if (test_thread_flag(TIF_32BIT)) {
720		elf_fpregset_t32 *fpregs32 = (elf_fpregset_t32 *)fpregs;
721
722		if (fprs & FPRS_DL)
723			memcpy(&fpregs32->pr_fr.pr_regs[0], kfpregs,
724			       sizeof(unsigned int) * 32);
725		else
726			memset(&fpregs32->pr_fr.pr_regs[0], 0,
727			       sizeof(unsigned int) * 32);
728		fpregs32->pr_qcnt = 0;
729		fpregs32->pr_q_entrysize = 8;
730		memset(&fpregs32->pr_q[0], 0,
731		       (sizeof(unsigned int) * 64));
732		if (fprs & FPRS_FEF) {
733			fpregs32->pr_fsr = (unsigned int) current_thread_info()->xfsr[0];
734			fpregs32->pr_en = 1;
735		} else {
736			fpregs32->pr_fsr = 0;
737			fpregs32->pr_en = 0;
738		}
739	} else {
740		if(fprs & FPRS_DL)
741			memcpy(&fpregs->pr_regs[0], kfpregs,
742			       sizeof(unsigned int) * 32);
743		else
744			memset(&fpregs->pr_regs[0], 0,
745			       sizeof(unsigned int) * 32);
746		if(fprs & FPRS_DU)
747			memcpy(&fpregs->pr_regs[16], kfpregs+16,
748			       sizeof(unsigned int) * 32);
749		else
750			memset(&fpregs->pr_regs[16], 0,
751			       sizeof(unsigned int) * 32);
752		if(fprs & FPRS_FEF) {
753			fpregs->pr_fsr = current_thread_info()->xfsr[0];
754			fpregs->pr_gsr = current_thread_info()->gsr[0];
755		} else {
756			fpregs->pr_fsr = fpregs->pr_gsr = 0;
757		}
758		fpregs->pr_fprs = fprs;
759	}
760	return 1;
761}
762EXPORT_SYMBOL(dump_fpu);
763
764unsigned long get_wchan(struct task_struct *task)
765{
766	unsigned long pc, fp, bias = 0;
767	struct thread_info *tp;
768	struct reg_window *rw;
769        unsigned long ret = 0;
770	int count = 0; 
771
772	if (!task || task == current ||
773            task->state == TASK_RUNNING)
774		goto out;
775
776	tp = task_thread_info(task);
777	bias = STACK_BIAS;
778	fp = task_thread_info(task)->ksp + bias;
779
780	do {
781		if (!kstack_valid(tp, fp))
782			break;
783		rw = (struct reg_window *) fp;
784		pc = rw->ins[7];
785		if (!in_sched_functions(pc)) {
786			ret = pc;
787			goto out;
788		}
789		fp = rw->ins[6] + bias;
790	} while (++count < 16);
791
792out:
793	return ret;
794}
v5.4
  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
 13#include <stdarg.h>
 14
 15#include <linux/errno.h>
 16#include <linux/export.h>
 17#include <linux/sched.h>
 18#include <linux/sched/debug.h>
 19#include <linux/sched/task.h>
 20#include <linux/sched/task_stack.h>
 21#include <linux/kernel.h>
 22#include <linux/mm.h>
 23#include <linux/fs.h>
 24#include <linux/smp.h>
 25#include <linux/stddef.h>
 26#include <linux/ptrace.h>
 27#include <linux/slab.h>
 28#include <linux/user.h>
 29#include <linux/delay.h>
 30#include <linux/compat.h>
 31#include <linux/tick.h>
 32#include <linux/init.h>
 33#include <linux/cpu.h>
 34#include <linux/perf_event.h>
 35#include <linux/elfcore.h>
 36#include <linux/sysrq.h>
 37#include <linux/nmi.h>
 38#include <linux/context_tracking.h>
 39#include <linux/signal.h>
 40
 41#include <linux/uaccess.h>
 42#include <asm/page.h>
 43#include <asm/pgalloc.h>
 44#include <asm/pgtable.h>
 45#include <asm/processor.h>
 46#include <asm/pstate.h>
 47#include <asm/elf.h>
 48#include <asm/fpumacro.h>
 49#include <asm/head.h>
 50#include <asm/cpudata.h>
 51#include <asm/mmu_context.h>
 52#include <asm/unistd.h>
 53#include <asm/hypervisor.h>
 54#include <asm/syscalls.h>
 55#include <asm/irq_regs.h>
 56#include <asm/smp.h>
 57#include <asm/pcr.h>
 58
 59#include "kstack.h"
 60
 61/* Idle loop support on sparc64. */
 62void arch_cpu_idle(void)
 63{
 64	if (tlb_type != hypervisor) {
 65		touch_nmi_watchdog();
 66		local_irq_enable();
 67	} else {
 68		unsigned long pstate;
 69
 70		local_irq_enable();
 71
 72                /* The sun4v sleeping code requires that we have PSTATE.IE cleared over
 73                 * the cpu sleep hypervisor call.
 74                 */
 75		__asm__ __volatile__(
 76			"rdpr %%pstate, %0\n\t"
 77			"andn %0, %1, %0\n\t"
 78			"wrpr %0, %%g0, %%pstate"
 79			: "=&r" (pstate)
 80			: "i" (PSTATE_IE));
 81
 82		if (!need_resched() && !cpu_is_offline(smp_processor_id())) {
 83			sun4v_cpu_yield();
 84			/* If resumed by cpu_poke then we need to explicitly
 85			 * call scheduler_ipi().
 86			 */
 87			scheduler_poke();
 88		}
 89
 90		/* Re-enable interrupts. */
 91		__asm__ __volatile__(
 92			"rdpr %%pstate, %0\n\t"
 93			"or %0, %1, %0\n\t"
 94			"wrpr %0, %%g0, %%pstate"
 95			: "=&r" (pstate)
 96			: "i" (PSTATE_IE));
 97	}
 98}
 99
100#ifdef CONFIG_HOTPLUG_CPU
101void arch_cpu_idle_dead(void)
102{
103	sched_preempt_enable_no_resched();
104	cpu_play_dead();
105}
106#endif
107
108#ifdef CONFIG_COMPAT
109static void show_regwindow32(struct pt_regs *regs)
110{
111	struct reg_window32 __user *rw;
112	struct reg_window32 r_w;
113	mm_segment_t old_fs;
114	
115	__asm__ __volatile__ ("flushw");
116	rw = compat_ptr((unsigned int)regs->u_regs[14]);
117	old_fs = get_fs();
118	set_fs (USER_DS);
119	if (copy_from_user (&r_w, rw, sizeof(r_w))) {
120		set_fs (old_fs);
121		return;
122	}
123
124	set_fs (old_fs);			
125	printk("l0: %08x l1: %08x l2: %08x l3: %08x "
126	       "l4: %08x l5: %08x l6: %08x l7: %08x\n",
127	       r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
128	       r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
129	printk("i0: %08x i1: %08x i2: %08x i3: %08x "
130	       "i4: %08x i5: %08x i6: %08x i7: %08x\n",
131	       r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
132	       r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
133}
134#else
135#define show_regwindow32(regs)	do { } while (0)
136#endif
137
138static void show_regwindow(struct pt_regs *regs)
139{
140	struct reg_window __user *rw;
141	struct reg_window *rwk;
142	struct reg_window r_w;
143	mm_segment_t old_fs;
144
145	if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
146		__asm__ __volatile__ ("flushw");
147		rw = (struct reg_window __user *)
148			(regs->u_regs[14] + STACK_BIAS);
149		rwk = (struct reg_window *)
150			(regs->u_regs[14] + STACK_BIAS);
151		if (!(regs->tstate & TSTATE_PRIV)) {
152			old_fs = get_fs();
153			set_fs (USER_DS);
154			if (copy_from_user (&r_w, rw, sizeof(r_w))) {
155				set_fs (old_fs);
156				return;
157			}
158			rwk = &r_w;
159			set_fs (old_fs);			
160		}
161	} else {
162		show_regwindow32(regs);
163		return;
164	}
165	printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
166	       rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
167	printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
168	       rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
169	printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
170	       rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
171	printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
172	       rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
173	if (regs->tstate & TSTATE_PRIV)
174		printk("I7: <%pS>\n", (void *) rwk->ins[7]);
175}
176
177void show_regs(struct pt_regs *regs)
178{
179	show_regs_print_info(KERN_DEFAULT);
180
181	printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x    %s\n", regs->tstate,
182	       regs->tpc, regs->tnpc, regs->y, print_tainted());
183	printk("TPC: <%pS>\n", (void *) regs->tpc);
184	printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
185	       regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
186	       regs->u_regs[3]);
187	printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
188	       regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
189	       regs->u_regs[7]);
190	printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
191	       regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
192	       regs->u_regs[11]);
193	printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
194	       regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
195	       regs->u_regs[15]);
196	printk("RPC: <%pS>\n", (void *) regs->u_regs[15]);
197	show_regwindow(regs);
198	show_stack(current, (unsigned long *) regs->u_regs[UREG_FP]);
199}
200
201union global_cpu_snapshot global_cpu_snapshot[NR_CPUS];
202static DEFINE_SPINLOCK(global_cpu_snapshot_lock);
203
204static void __global_reg_self(struct thread_info *tp, struct pt_regs *regs,
205			      int this_cpu)
206{
207	struct global_reg_snapshot *rp;
208
209	flushw_all();
210
211	rp = &global_cpu_snapshot[this_cpu].reg;
212
213	rp->tstate = regs->tstate;
214	rp->tpc = regs->tpc;
215	rp->tnpc = regs->tnpc;
216	rp->o7 = regs->u_regs[UREG_I7];
217
218	if (regs->tstate & TSTATE_PRIV) {
219		struct reg_window *rw;
220
221		rw = (struct reg_window *)
222			(regs->u_regs[UREG_FP] + STACK_BIAS);
223		if (kstack_valid(tp, (unsigned long) rw)) {
224			rp->i7 = rw->ins[7];
225			rw = (struct reg_window *)
226				(rw->ins[6] + STACK_BIAS);
227			if (kstack_valid(tp, (unsigned long) rw))
228				rp->rpc = rw->ins[7];
229		}
230	} else {
231		rp->i7 = 0;
232		rp->rpc = 0;
233	}
234	rp->thread = tp;
235}
236
237/* In order to avoid hangs we do not try to synchronize with the
238 * global register dump client cpus.  The last store they make is to
239 * the thread pointer, so do a short poll waiting for that to become
240 * non-NULL.
241 */
242static void __global_reg_poll(struct global_reg_snapshot *gp)
243{
244	int limit = 0;
245
246	while (!gp->thread && ++limit < 100) {
247		barrier();
248		udelay(1);
249	}
250}
251
252void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
253{
254	struct thread_info *tp = current_thread_info();
255	struct pt_regs *regs = get_irq_regs();
256	unsigned long flags;
257	int this_cpu, cpu;
258
259	if (!regs)
260		regs = tp->kregs;
261
262	spin_lock_irqsave(&global_cpu_snapshot_lock, flags);
263
264	this_cpu = raw_smp_processor_id();
265
266	memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
267
268	if (cpumask_test_cpu(this_cpu, mask) && !exclude_self)
269		__global_reg_self(tp, regs, this_cpu);
270
271	smp_fetch_global_regs();
272
273	for_each_cpu(cpu, mask) {
274		struct global_reg_snapshot *gp;
275
276		if (exclude_self && cpu == this_cpu)
277			continue;
278
279		gp = &global_cpu_snapshot[cpu].reg;
280
281		__global_reg_poll(gp);
282
283		tp = gp->thread;
284		printk("%c CPU[%3d]: TSTATE[%016lx] TPC[%016lx] TNPC[%016lx] TASK[%s:%d]\n",
285		       (cpu == this_cpu ? '*' : ' '), cpu,
286		       gp->tstate, gp->tpc, gp->tnpc,
287		       ((tp && tp->task) ? tp->task->comm : "NULL"),
288		       ((tp && tp->task) ? tp->task->pid : -1));
289
290		if (gp->tstate & TSTATE_PRIV) {
291			printk("             TPC[%pS] O7[%pS] I7[%pS] RPC[%pS]\n",
292			       (void *) gp->tpc,
293			       (void *) gp->o7,
294			       (void *) gp->i7,
295			       (void *) gp->rpc);
296		} else {
297			printk("             TPC[%lx] O7[%lx] I7[%lx] RPC[%lx]\n",
298			       gp->tpc, gp->o7, gp->i7, gp->rpc);
299		}
300
301		touch_nmi_watchdog();
302	}
303
304	memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
305
306	spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags);
307}
308
309#ifdef CONFIG_MAGIC_SYSRQ
310
311static void sysrq_handle_globreg(int key)
312{
313	trigger_all_cpu_backtrace();
314}
315
316static struct sysrq_key_op sparc_globalreg_op = {
317	.handler	= sysrq_handle_globreg,
318	.help_msg	= "global-regs(y)",
319	.action_msg	= "Show Global CPU Regs",
320};
321
322static void __global_pmu_self(int this_cpu)
323{
324	struct global_pmu_snapshot *pp;
325	int i, num;
326
327	if (!pcr_ops)
328		return;
329
330	pp = &global_cpu_snapshot[this_cpu].pmu;
331
332	num = 1;
333	if (tlb_type == hypervisor &&
334	    sun4v_chip_type >= SUN4V_CHIP_NIAGARA4)
335		num = 4;
336
337	for (i = 0; i < num; i++) {
338		pp->pcr[i] = pcr_ops->read_pcr(i);
339		pp->pic[i] = pcr_ops->read_pic(i);
340	}
341}
342
343static void __global_pmu_poll(struct global_pmu_snapshot *pp)
344{
345	int limit = 0;
346
347	while (!pp->pcr[0] && ++limit < 100) {
348		barrier();
349		udelay(1);
350	}
351}
352
353static void pmu_snapshot_all_cpus(void)
354{
355	unsigned long flags;
356	int this_cpu, cpu;
357
358	spin_lock_irqsave(&global_cpu_snapshot_lock, flags);
359
360	memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
361
362	this_cpu = raw_smp_processor_id();
363
364	__global_pmu_self(this_cpu);
365
366	smp_fetch_global_pmu();
367
368	for_each_online_cpu(cpu) {
369		struct global_pmu_snapshot *pp = &global_cpu_snapshot[cpu].pmu;
370
371		__global_pmu_poll(pp);
372
373		printk("%c CPU[%3d]: PCR[%08lx:%08lx:%08lx:%08lx] PIC[%08lx:%08lx:%08lx:%08lx]\n",
374		       (cpu == this_cpu ? '*' : ' '), cpu,
375		       pp->pcr[0], pp->pcr[1], pp->pcr[2], pp->pcr[3],
376		       pp->pic[0], pp->pic[1], pp->pic[2], pp->pic[3]);
377
378		touch_nmi_watchdog();
379	}
380
381	memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
382
383	spin_unlock_irqrestore(&global_cpu_snapshot_lock, flags);
384}
385
386static void sysrq_handle_globpmu(int key)
387{
388	pmu_snapshot_all_cpus();
389}
390
391static struct sysrq_key_op sparc_globalpmu_op = {
392	.handler	= sysrq_handle_globpmu,
393	.help_msg	= "global-pmu(x)",
394	.action_msg	= "Show Global PMU Regs",
395};
396
397static int __init sparc_sysrq_init(void)
398{
399	int ret = register_sysrq_key('y', &sparc_globalreg_op);
400
401	if (!ret)
402		ret = register_sysrq_key('x', &sparc_globalpmu_op);
403	return ret;
404}
405
406core_initcall(sparc_sysrq_init);
407
408#endif
409
410/* Free current thread data structures etc.. */
411void exit_thread(struct task_struct *tsk)
412{
413	struct thread_info *t = task_thread_info(tsk);
414
415	if (t->utraps) {
416		if (t->utraps[0] < 2)
417			kfree (t->utraps);
418		else
419			t->utraps[0]--;
420	}
421}
422
423void flush_thread(void)
424{
425	struct thread_info *t = current_thread_info();
426	struct mm_struct *mm;
427
428	mm = t->task->mm;
429	if (mm)
430		tsb_context_switch(mm);
431
432	set_thread_wsaved(0);
433
434	/* Clear FPU register state. */
435	t->fpsaved[0] = 0;
436}
437
438/* It's a bit more tricky when 64-bit tasks are involved... */
439static unsigned long clone_stackframe(unsigned long csp, unsigned long psp)
440{
441	bool stack_64bit = test_thread_64bit_stack(psp);
442	unsigned long fp, distance, rval;
443
444	if (stack_64bit) {
445		csp += STACK_BIAS;
446		psp += STACK_BIAS;
447		__get_user(fp, &(((struct reg_window __user *)psp)->ins[6]));
448		fp += STACK_BIAS;
449		if (test_thread_flag(TIF_32BIT))
450			fp &= 0xffffffff;
451	} else
452		__get_user(fp, &(((struct reg_window32 __user *)psp)->ins[6]));
453
454	/* Now align the stack as this is mandatory in the Sparc ABI
455	 * due to how register windows work.  This hides the
456	 * restriction from thread libraries etc.
457	 */
458	csp &= ~15UL;
459
460	distance = fp - psp;
461	rval = (csp - distance);
462	if (copy_in_user((void __user *) rval, (void __user *) psp, distance))
463		rval = 0;
464	else if (!stack_64bit) {
465		if (put_user(((u32)csp),
466			     &(((struct reg_window32 __user *)rval)->ins[6])))
467			rval = 0;
468	} else {
469		if (put_user(((u64)csp - STACK_BIAS),
470			     &(((struct reg_window __user *)rval)->ins[6])))
471			rval = 0;
472		else
473			rval = rval - STACK_BIAS;
474	}
475
476	return rval;
477}
478
479/* Standard stuff. */
480static inline void shift_window_buffer(int first_win, int last_win,
481				       struct thread_info *t)
482{
483	int i;
484
485	for (i = first_win; i < last_win; i++) {
486		t->rwbuf_stkptrs[i] = t->rwbuf_stkptrs[i+1];
487		memcpy(&t->reg_window[i], &t->reg_window[i+1],
488		       sizeof(struct reg_window));
489	}
490}
491
492void synchronize_user_stack(void)
493{
494	struct thread_info *t = current_thread_info();
495	unsigned long window;
496
497	flush_user_windows();
498	if ((window = get_thread_wsaved()) != 0) {
499		window -= 1;
500		do {
501			struct reg_window *rwin = &t->reg_window[window];
502			int winsize = sizeof(struct reg_window);
503			unsigned long sp;
504
505			sp = t->rwbuf_stkptrs[window];
506
507			if (test_thread_64bit_stack(sp))
508				sp += STACK_BIAS;
509			else
510				winsize = sizeof(struct reg_window32);
511
512			if (!copy_to_user((char __user *)sp, rwin, winsize)) {
513				shift_window_buffer(window, get_thread_wsaved() - 1, t);
514				set_thread_wsaved(get_thread_wsaved() - 1);
515			}
516		} while (window--);
517	}
518}
519
520static void stack_unaligned(unsigned long sp)
521{
522	force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *) sp, 0);
 
 
 
 
 
 
 
523}
524
525static const char uwfault32[] = KERN_INFO \
526	"%s[%d]: bad register window fault: SP %08lx (orig_sp %08lx) TPC %08lx O7 %08lx\n";
527static const char uwfault64[] = KERN_INFO \
528	"%s[%d]: bad register window fault: SP %016lx (orig_sp %016lx) TPC %08lx O7 %016lx\n";
529
530void fault_in_user_windows(struct pt_regs *regs)
531{
532	struct thread_info *t = current_thread_info();
533	unsigned long window;
534
535	flush_user_windows();
536	window = get_thread_wsaved();
537
538	if (likely(window != 0)) {
539		window -= 1;
540		do {
541			struct reg_window *rwin = &t->reg_window[window];
542			int winsize = sizeof(struct reg_window);
543			unsigned long sp, orig_sp;
544
545			orig_sp = sp = t->rwbuf_stkptrs[window];
546
547			if (test_thread_64bit_stack(sp))
548				sp += STACK_BIAS;
549			else
550				winsize = sizeof(struct reg_window32);
551
552			if (unlikely(sp & 0x7UL))
553				stack_unaligned(sp);
554
555			if (unlikely(copy_to_user((char __user *)sp,
556						  rwin, winsize))) {
557				if (show_unhandled_signals)
558					printk_ratelimited(is_compat_task() ?
559							   uwfault32 : uwfault64,
560							   current->comm, current->pid,
561							   sp, orig_sp,
562							   regs->tpc,
563							   regs->u_regs[UREG_I7]);
564				goto barf;
565			}
566		} while (window--);
567	}
568	set_thread_wsaved(0);
569	return;
570
571barf:
572	set_thread_wsaved(window + 1);
573	force_sig(SIGSEGV);
 
574}
575
576asmlinkage long sparc_do_fork(unsigned long clone_flags,
577			      unsigned long stack_start,
578			      struct pt_regs *regs,
579			      unsigned long stack_size)
580{
581	int __user *parent_tid_ptr, *child_tid_ptr;
582	unsigned long orig_i1 = regs->u_regs[UREG_I1];
583	long ret;
584
585#ifdef CONFIG_COMPAT
586	if (test_thread_flag(TIF_32BIT)) {
587		parent_tid_ptr = compat_ptr(regs->u_regs[UREG_I2]);
588		child_tid_ptr = compat_ptr(regs->u_regs[UREG_I4]);
589	} else
590#endif
591	{
592		parent_tid_ptr = (int __user *) regs->u_regs[UREG_I2];
593		child_tid_ptr = (int __user *) regs->u_regs[UREG_I4];
594	}
595
596	ret = do_fork(clone_flags, stack_start, stack_size,
597		      parent_tid_ptr, child_tid_ptr);
598
599	/* If we get an error and potentially restart the system
600	 * call, we're screwed because copy_thread() clobbered
601	 * the parent's %o1.  So detect that case and restore it
602	 * here.
603	 */
604	if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
605		regs->u_regs[UREG_I1] = orig_i1;
606
607	return ret;
608}
609
610/* Copy a Sparc thread.  The fork() return value conventions
611 * under SunOS are nothing short of bletcherous:
612 * Parent -->  %o0 == childs  pid, %o1 == 0
613 * Child  -->  %o0 == parents pid, %o1 == 1
614 */
615int copy_thread(unsigned long clone_flags, unsigned long sp,
616		unsigned long arg, struct task_struct *p)
617{
618	struct thread_info *t = task_thread_info(p);
619	struct pt_regs *regs = current_pt_regs();
620	struct sparc_stackf *parent_sf;
621	unsigned long child_stack_sz;
622	char *child_trap_frame;
623
624	/* Calculate offset to stack_frame & pt_regs */
625	child_stack_sz = (STACKFRAME_SZ + TRACEREG_SZ);
626	child_trap_frame = (task_stack_page(p) +
627			    (THREAD_SIZE - child_stack_sz));
628
629	t->new_child = 1;
630	t->ksp = ((unsigned long) child_trap_frame) - STACK_BIAS;
631	t->kregs = (struct pt_regs *) (child_trap_frame +
632				       sizeof(struct sparc_stackf));
633	t->fpsaved[0] = 0;
634
635	if (unlikely(p->flags & PF_KTHREAD)) {
636		memset(child_trap_frame, 0, child_stack_sz);
637		__thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] = 
638			(current_pt_regs()->tstate + 1) & TSTATE_CWP;
639		t->current_ds = ASI_P;
640		t->kregs->u_regs[UREG_G1] = sp; /* function */
641		t->kregs->u_regs[UREG_G2] = arg;
642		return 0;
643	}
644
645	parent_sf = ((struct sparc_stackf *) regs) - 1;
646	memcpy(child_trap_frame, parent_sf, child_stack_sz);
647	if (t->flags & _TIF_32BIT) {
648		sp &= 0x00000000ffffffffUL;
649		regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
650	}
651	t->kregs->u_regs[UREG_FP] = sp;
652	__thread_flag_byte_ptr(t)[TI_FLAG_BYTE_CWP] = 
653		(regs->tstate + 1) & TSTATE_CWP;
654	t->current_ds = ASI_AIUS;
655	if (sp != regs->u_regs[UREG_FP]) {
656		unsigned long csp;
657
658		csp = clone_stackframe(sp, regs->u_regs[UREG_FP]);
659		if (!csp)
660			return -EFAULT;
661		t->kregs->u_regs[UREG_FP] = csp;
662	}
663	if (t->utraps)
664		t->utraps[0]++;
665
666	/* Set the return value for the child. */
667	t->kregs->u_regs[UREG_I0] = current->pid;
668	t->kregs->u_regs[UREG_I1] = 1;
669
670	/* Set the second return value for the parent. */
671	regs->u_regs[UREG_I1] = 0;
672
673	if (clone_flags & CLONE_SETTLS)
674		t->kregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
675
676	return 0;
677}
678
679/* TIF_MCDPER in thread info flags for current task is updated lazily upon
680 * a context switch. Update this flag in current task's thread flags
681 * before dup so the dup'd task will inherit the current TIF_MCDPER flag.
682 */
683int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
684{
685	if (adi_capable()) {
686		register unsigned long tmp_mcdper;
687
688		__asm__ __volatile__(
689			".word 0x83438000\n\t"	/* rd  %mcdper, %g1 */
690			"mov %%g1, %0\n\t"
691			: "=r" (tmp_mcdper)
692			:
693			: "g1");
694		if (tmp_mcdper)
695			set_thread_flag(TIF_MCDPER);
696		else
697			clear_thread_flag(TIF_MCDPER);
698	}
699
700	*dst = *src;
701	return 0;
702}
703
704typedef struct {
705	union {
706		unsigned int	pr_regs[32];
707		unsigned long	pr_dregs[16];
708	} pr_fr;
709	unsigned int __unused;
710	unsigned int	pr_fsr;
711	unsigned char	pr_qcnt;
712	unsigned char	pr_q_entrysize;
713	unsigned char	pr_en;
714	unsigned int	pr_q[64];
715} elf_fpregset_t32;
716
717/*
718 * fill in the fpu structure for a core dump.
719 */
720int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
721{
722	unsigned long *kfpregs = current_thread_info()->fpregs;
723	unsigned long fprs = current_thread_info()->fpsaved[0];
724
725	if (test_thread_flag(TIF_32BIT)) {
726		elf_fpregset_t32 *fpregs32 = (elf_fpregset_t32 *)fpregs;
727
728		if (fprs & FPRS_DL)
729			memcpy(&fpregs32->pr_fr.pr_regs[0], kfpregs,
730			       sizeof(unsigned int) * 32);
731		else
732			memset(&fpregs32->pr_fr.pr_regs[0], 0,
733			       sizeof(unsigned int) * 32);
734		fpregs32->pr_qcnt = 0;
735		fpregs32->pr_q_entrysize = 8;
736		memset(&fpregs32->pr_q[0], 0,
737		       (sizeof(unsigned int) * 64));
738		if (fprs & FPRS_FEF) {
739			fpregs32->pr_fsr = (unsigned int) current_thread_info()->xfsr[0];
740			fpregs32->pr_en = 1;
741		} else {
742			fpregs32->pr_fsr = 0;
743			fpregs32->pr_en = 0;
744		}
745	} else {
746		if(fprs & FPRS_DL)
747			memcpy(&fpregs->pr_regs[0], kfpregs,
748			       sizeof(unsigned int) * 32);
749		else
750			memset(&fpregs->pr_regs[0], 0,
751			       sizeof(unsigned int) * 32);
752		if(fprs & FPRS_DU)
753			memcpy(&fpregs->pr_regs[16], kfpregs+16,
754			       sizeof(unsigned int) * 32);
755		else
756			memset(&fpregs->pr_regs[16], 0,
757			       sizeof(unsigned int) * 32);
758		if(fprs & FPRS_FEF) {
759			fpregs->pr_fsr = current_thread_info()->xfsr[0];
760			fpregs->pr_gsr = current_thread_info()->gsr[0];
761		} else {
762			fpregs->pr_fsr = fpregs->pr_gsr = 0;
763		}
764		fpregs->pr_fprs = fprs;
765	}
766	return 1;
767}
768EXPORT_SYMBOL(dump_fpu);
769
770unsigned long get_wchan(struct task_struct *task)
771{
772	unsigned long pc, fp, bias = 0;
773	struct thread_info *tp;
774	struct reg_window *rw;
775        unsigned long ret = 0;
776	int count = 0; 
777
778	if (!task || task == current ||
779            task->state == TASK_RUNNING)
780		goto out;
781
782	tp = task_thread_info(task);
783	bias = STACK_BIAS;
784	fp = task_thread_info(task)->ksp + bias;
785
786	do {
787		if (!kstack_valid(tp, fp))
788			break;
789		rw = (struct reg_window *) fp;
790		pc = rw->ins[7];
791		if (!in_sched_functions(pc)) {
792			ret = pc;
793			goto out;
794		}
795		fp = rw->ins[6] + bias;
796	} while (++count < 16);
797
798out:
799	return ret;
800}