aboutsummaryrefslogtreecommitdiff
path: root/arch/sparc/kernel/signal32.c
blob: 62deba7be1a9ed6dba7af17177c3279577a6be85 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
/*  arch/sparc64/kernel/signal32.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 *  Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
 *  Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
 *  Copyright (C) 1997 Eddie C. Dost   (ecd@skynet.be)
 *  Copyright (C) 1997,1998 Jakub Jelinek   (jj@sunsite.mff.cuni.cz)
 */

#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/signal.h>
#include <linux/errno.h>
#include <linux/wait.h>
#include <linux/ptrace.h>
#include <linux/unistd.h>
#include <linux/mm.h>
#include <linux/tty.h>
#include <linux/binfmts.h>
#include <linux/compat.h>
#include <linux/bitops.h>
#include <linux/tracehook.h>

#include <asm/uaccess.h>
#include <asm/ptrace.h>
#include <asm/pgtable.h>
#include <asm/psrcompat.h>
#include <asm/fpumacro.h>
#include <asm/visasm.h>
#include <asm/compat_signal.h>
#include <asm/switch_to.h>

#include "sigutil.h"
#include "kernel.h"

/* This magic should be in g_upper[0] for all upper parts
 * to be valid.
 */
#define SIGINFO_EXTRA_V8PLUS_MAGIC	0x130e269
typedef struct {
	unsigned int g_upper[8];
	unsigned int o_upper[8];
	unsigned int asi;
} siginfo_extra_v8plus_t;

struct signal_frame32 {
	struct sparc_stackf32	ss;
	__siginfo32_t		info;
	/* __siginfo_fpu_t * */ u32 fpu_save;
	unsigned int		insns[2];
	unsigned int		extramask[_COMPAT_NSIG_WORDS - 1];
	unsigned int		extra_size; /* Should be sizeof(siginfo_extra_v8plus_t) */
	/* Only valid if (info.si_regs.psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS */
	siginfo_extra_v8plus_t	v8plus;
	/* __siginfo_rwin_t * */u32 rwin_save;
} __attribute__((aligned(8)));

struct rt_signal_frame32 {
	struct sparc_stackf32	ss;
	compat_siginfo_t	info;
	struct pt_regs32	regs;
	compat_sigset_t		mask;
	/* __siginfo_fpu_t * */ u32 fpu_save;
	unsigned int		insns[2];
	compat_stack_t		stack;
	unsigned int		extra_size; /* Should be sizeof(siginfo_extra_v8plus_t) */
	/* Only valid if (regs.psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS */
	siginfo_extra_v8plus_t	v8plus;
	/* __siginfo_rwin_t * */u32 rwin_save;
} __attribute__((aligned(8)));

int copy_siginfo_to_user32(compat_siginfo_t __user *to, const siginfo_t *from)
{
	int err;

	if (!access_ok(VERIFY_WRITE, to, sizeof(compat_siginfo_t)))
		return -EFAULT;

	/* If you change siginfo_t structure, please be sure
	   this code is fixed accordingly.
	   It should never copy any pad contained in the structure
	   to avoid security leaks, but must copy the generic
	   3 ints plus the relevant union member.
	   This routine must convert siginfo from 64bit to 32bit as well
	   at the same time.  */
	err = __put_user(from->si_signo, &to->si_signo);
	err |= __put_user(from->si_errno, &to->si_errno);
	err |= __put_user((short)from->si_code, &to->si_code);
	if (from->si_code < 0)
		err |= __copy_to_user(&to->_sifields._pad, &from->_sifields._pad, SI_PAD_SIZE);
	else {
		switch (from->si_code >> 16) {
		case __SI_TIMER >> 16:
			err |= __put_user(from->si_tid, &to->si_tid);
			err |= __put_user(from->si_overrun, &to->si_overrun);
			err |= __put_user(from->si_int, &to->si_int);
			break;
		case __SI_CHLD >> 16:
			err |= __put_user(from->si_utime, &to->si_utime);
			err |= __put_user(from->si_stime, &to->si_stime);
			err |= __put_user(from->si_status, &to->si_status);
		default:
			err |= __put_user(from->si_pid, &to->si_pid);
			err |= __put_user(from->si_uid, &to->si_uid);
			break;
		case __SI_FAULT >> 16:
			err |= __put_user(from->si_trapno, &to->si_trapno);
			err |= __put_user((unsigned long)from->si_addr, &to->si_addr);
			break;
		case __SI_POLL >> 16:
			err |= __put_user(from->si_band, &to->si_band);
			err |= __put_user(from->si_fd, &to->si_fd);
			break;
		case __SI_RT >> 16: /* This is not generated by the kernel as of now.  */
		case __SI_MESGQ >> 16:
			err |= __put_user(from->si_pid, &to->si_pid);
			err |= __put_user(from->si_uid, &to->si_uid);
			err |= __put_user(from->si_int, &to->si_int);
			break;
		}
	}
	return err;
}

/* CAUTION: This is just a very minimalist implementation for the
 *          sake of compat_sys_rt_sigqueueinfo()
 */
int copy_siginfo_from_user32(siginfo_t *to, compat_siginfo_t __user *from)
{
	if (!access_ok(VERIFY_WRITE, from, sizeof(compat_siginfo_t)))
		return -EFAULT;

	if (copy_from_user(to, from, 3*sizeof(int)) ||
	    copy_from_user(to->_sifields._pad, from->_sifields._pad,
			   SI_PAD_SIZE))
		return -EFAULT;

	return 0;
}

void do_sigreturn32(struct pt_regs *regs)
{
	struct signal_frame32 __user *sf;
	compat_uptr_t fpu_save;
	compat_uptr_t rwin_save;
	unsigned int psr;
	unsigned pc, npc;
	sigset_t set;
	compat_sigset_t seta;
	int err, i;
	
	/* Always make any pending restarted system calls return -EINTR */
	current_thread_info()->restart_block.fn = do_no_restart_syscall;

	synchronize_user_stack();

	regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
	sf = (struct signal_frame32 __user *) regs->u_regs[UREG_FP];

	/* 1. Make sure we are not getting garbage from the user */
	if (!access_ok(VERIFY_READ, sf, sizeof(*sf)) ||
	    (((unsigned long) sf) & 3))
		goto segv;

	if (get_user(pc, &sf->info.si_regs.pc) ||
	    __get_user(npc, &sf->info.si_regs.npc))
		goto segv;

	if ((pc | npc) & 3)
		goto segv;

	if (test_thread_flag(TIF_32BIT)) {
		pc &= 0xffffffff;
		npc &= 0xffffffff;
	}
	regs->tpc = pc;
	regs->tnpc = npc;

	/* 2. Restore the state */
	err = __get_user(regs->y, &sf->info.si_regs.y);
	err |= __get_user(psr, &sf->info.si_regs.psr);

	for (i = UREG_G1; i <= UREG_I7; i++)
		err |= __get_user(regs->u_regs[i], &sf->info.si_regs.u_regs[i]);
	if ((psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS) {
		err |= __get_user(i, &sf->v8plus.g_upper[0]);
		if (i == SIGINFO_EXTRA_V8PLUS_MAGIC) {
			unsigned long asi;

			for (i = UREG_G1; i <= UREG_I7; i++)
				err |= __get_user(((u32 *)regs->u_regs)[2*i], &sf->v8plus.g_upper[i]);
			err |= __get_user(asi, &sf->v8plus.asi);
			regs->tstate &= ~TSTATE_ASI;
			regs->tstate |= ((asi & 0xffUL) << 24UL);
		}
	}

	/* User can only change condition codes in %tstate. */
	regs->tstate &= ~(TSTATE_ICC|TSTATE_XCC);
	regs->tstate |= psr_to_tstate_icc(psr);

	/* Prevent syscall restart.  */
	pt_regs_clear_syscall(regs);

	err |= __get_user(fpu_save, &sf->fpu_save);
	if (!err && fpu_save)
		err |= restore_fpu_state(regs, compat_ptr(fpu_save));
	err |= __get_user(rwin_save, &sf->rwin_save);
	if (!err && rwin_save) {
		if (restore_rwin_state(compat_ptr(rwin_save)))
			goto segv;
	}
	err |= __get_user(seta.sig[0], &sf->info.si_mask);
	err |= copy_from_user(&seta.sig[1], &sf->extramask,
			      (_COMPAT_NSIG_WORDS - 1) * sizeof(unsigned int));
	if (err)
	    	goto segv;

	set.sig[0] = seta.sig[0] + (((long)seta.sig[1]) << 32);
	set_current_blocked(&set);
	return;

segv:
	force_sig(SIGSEGV, current);
}

asmlinkage void do_rt_sigreturn32(struct pt_regs *regs)
{
	struct rt_signal_frame32 __user *sf;
	unsigned int psr, pc, npc;
	compat_uptr_t fpu_save;
	compat_uptr_t rwin_save;
	sigset_t set;
	compat_sigset_t seta;
	int err, i;
	
	/* Always make any pending restarted system calls return -EINTR */
	current_thread_info()->restart_block.fn = do_no_restart_syscall;

	synchronize_user_stack();
	regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
	sf = (struct rt_signal_frame32 __user *) regs->u_regs[UREG_FP];

	/* 1. Make sure we are not getting garbage from the user */
	if (!access_ok(VERIFY_READ, sf, sizeof(*sf)) ||
	    (((unsigned long) sf) & 3))
		goto segv;

	if (get_user(pc, &sf->regs.pc) || 
	    __get_user(npc, &sf->regs.npc))
		goto segv;

	if ((pc | npc) & 3)
		goto segv;

	if (test_thread_flag(TIF_32BIT)) {
		pc &= 0xffffffff;
		npc &= 0xffffffff;
	}
	regs->tpc = pc;
	regs->tnpc = npc;

	/* 2. Restore the state */
	err = __get_user(regs->y, &sf->regs.y);
	err |= __get_user(psr, &sf->regs.psr);
	
	for (i = UREG_G1; i <= UREG_I7; i++)
		err |= __get_user(regs->u_regs[i], &sf->regs.u_regs[i]);
	if ((psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS) {
		err |= __get_user(i, &sf->v8plus.g_upper[0]);
		if (i == SIGINFO_EXTRA_V8PLUS_MAGIC) {
			unsigned long asi;

			for (i = UREG_G1; i <= UREG_I7; i++)
				err |= __get_user(((u32 *)regs->u_regs)[2*i], &sf->v8plus.g_upper[i]);
			err |= __get_user(asi, &sf->v8plus.asi);
			regs->tstate &= ~TSTATE_ASI;
			regs->tstate |= ((asi & 0xffUL) << 24UL);
		}
	}

	/* User can only change condition codes in %tstate. */
	regs->tstate &= ~(TSTATE_ICC|TSTATE_XCC);
	regs->tstate |= psr_to_tstate_icc(psr);

	/* Prevent syscall restart.  */
	pt_regs_clear_syscall(regs);

	err |= __get_user(fpu_save, &sf->fpu_save);
	if (!err && fpu_save)
		err |= restore_fpu_state(regs, compat_ptr(fpu_save));
	err |= copy_from_user(&seta, &sf->mask, sizeof(compat_sigset_t));
	err |= compat_restore_altstack(&sf->stack);
	if (err)
		goto segv;
		
	err |= __get_user(rwin_save, &sf->rwin_save);
	if (!err && rwin_save) {
		if (restore_rwin_state(compat_ptr(rwin_save)))
			goto segv;
	}

	set.sig[0] = seta.sig[0] + (((long)seta.sig[1]) << 32);
	set_current_blocked(&set);
	return;
segv:
	force_sig(SIGSEGV, current);
}

/* Checks if the fp is valid */
static int invalid_frame_pointer(void __user *fp, int fplen)
{
	if ((((unsigned long) fp) & 7) || ((unsigned long)fp) > 0x100000000ULL - fplen)
		return 1;
	return 0;
}

static void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, unsigned long framesize)
{
	unsigned long sp;
	
	regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
	sp = regs->u_regs[UREG_FP];
	
	/*
	 * If we are on the alternate signal stack and would overflow it, don't.
	 * Return an always-bogus address instead so we will die with SIGSEGV.
	 */
	if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize)))
		return (void __user *) -1L;

	/* This is the X/Open sanctioned signal stack switching.  */
	sp = sigsp(sp, ksig) - framesize;

	/* Always align the stack frame.  This handles two cases.  First,
	 * sigaltstack need not be mindful of platform specific stack
	 * alignment.  Second, if we took this signal because the stack
	 * is not aligned properly, we'd like to take the signal cleanly
	 * and report that.
	 */
	sp &= ~15UL;

	return (void __user *) sp;
}

/* The I-cache flush instruction only works in the primary ASI, which
 * right now is the nucleus, aka. kernel space.
 *
 * Therefore we have to kick the instructions out using the kernel
 * side linear mapping of the physical address backing the user
 * instructions.
 */
static void flush_signal_insns(unsigned long address)
{
	unsigned long pstate, paddr;
	pte_t *ptep, pte;
	pgd_t *pgdp;
	pud_t *pudp;
	pmd_t *pmdp;

	/* Commit all stores of the instructions we are about to flush.  */
	wmb();

	/* Disable cross-call reception.  In this way even a very wide
	 * munmap() on another cpu can't tear down the page table
	 * hierarchy from underneath us, since that can't complete
	 * until the IPI tlb flush returns.
	 */

	__asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
	__asm__ __volatile__("wrpr %0, %1, %%pstate"
				: : "r" (pstate), "i" (PSTATE_IE));

	pgdp = pgd_offset(current->mm, address);
	if (pgd_none(*pgdp))
		goto out_irqs_on;
	pudp = pud_offset(pgdp, address);
	if (pud_none(*pudp))
		goto out_irqs_on;
	pmdp = pmd_offset(pudp, address);
	if (pmd_none(*pmdp))
		goto out_irqs_on;

	ptep = pte_offset_map(pmdp, address);
	pte = *ptep;
	if (!pte_present(pte))
		goto out_unmap;

	paddr = (unsigned long) page_address(pte_page(pte));

	__asm__ __volatile__("flush	%0 + %1"
			     : /* no outputs */
			     : "r" (paddr),
			       "r" (address & (PAGE_SIZE - 1))
			     : "memory");

out_unmap:
	pte_unmap(ptep);
out_irqs_on:
	__asm__ __volatile__("wrpr %0, 0x0, %%pstate" : : "r" (pstate));

}

static int setup_frame32(struct ksignal *ksig, struct pt_regs *regs,
			 sigset_t *oldset)
{
	struct signal_frame32 __user *sf;
	int i, err, wsaved;
	void __user *tail;
	int sigframe_size;
	u32 psr;
	compat_sigset_t seta;

	/* 1. Make sure everything is clean */
	synchronize_user_stack();
	save_and_clear_fpu();
	
	wsaved = get_thread_wsaved();

	sigframe_size = sizeof(*sf);
	if (current_thread_info()->fpsaved[0] & FPRS_FEF)
		sigframe_size += sizeof(__siginfo_fpu_t);
	if (wsaved)
		sigframe_size += sizeof(__siginfo_rwin_t);

	sf = (struct signal_frame32 __user *)
		get_sigframe(ksig, regs, sigframe_size);
	
	if (invalid_frame_pointer(sf, sigframe_size)) {
		do_exit(SIGILL);
		return -EINVAL;
	}

	tail = (sf + 1);

	/* 2. Save the current process state */
	if (test_thread_flag(TIF_32BIT)) {
		regs->tpc &= 0xffffffff;
		regs->tnpc &= 0xffffffff;
	}
	err  = put_user(regs->tpc, &sf->info.si_regs.pc);
	err |= __put_user(regs->tnpc, &sf->info.si_regs.npc);
	err |= __put_user(regs->y, &sf->info.si_regs.y);
	psr = tstate_to_psr(regs->tstate);
	if (current_thread_info()->fpsaved[0] & FPRS_FEF)
		psr |= PSR_EF;
	err |= __put_user(psr, &sf->info.si_regs.psr);
	for (i = 0; i < 16; i++)
		err |= __put_user(regs->u_regs[i], &sf->info.si_regs.u_regs[i]);
	err |= __put_user(sizeof(siginfo_extra_v8plus_t), &sf->extra_size);
	err |= __put_user(SIGINFO_EXTRA_V8PLUS_MAGIC, &sf->v8plus.g_upper[0]);
	for (i = 1; i < 16; i++)
		err |= __put_user(((u32 *)regs->u_regs)[2*i],
				  &sf->v8plus.g_upper[i]);
	err |= __put_user((regs->tstate & TSTATE_ASI) >> 24UL,
			  &sf->v8plus.asi);

	if (psr & PSR_EF) {
		__siginfo_fpu_t __user *fp = tail;
		tail += sizeof(*fp);
		err |= save_fpu_state(regs, fp);
		err |= __put_user((u64)fp, &sf->fpu_save);
	} else {
		err |= __put_user(0, &sf->fpu_save);
	}
	if (wsaved) {
		__siginfo_rwin_t __user *rwp = tail;
		tail += sizeof(*rwp);
		err |= save_rwin_state(wsaved, rwp);
		err |= __put_user((u64)rwp, &sf->rwin_save);
		set_thread_wsaved(0);
	} else {
		err |= __put_user(0, &sf->rwin_save);
	}

	/* If these change we need to know - assignments to seta relies on these sizes */
	BUILD_BUG_ON(_NSIG_WORDS != 1);
	BUILD_BUG_ON(_COMPAT_NSIG_WORDS != 2);
	seta.sig[1] = (oldset->sig[0] >> 32);
	seta.sig[0] = oldset->sig[0];

	err |= __put_user(seta.sig[0], &sf->info.si_mask);
	err |= __copy_to_user(sf->extramask, &seta.sig[1],
			      (_COMPAT_NSIG_WORDS - 1) * sizeof(unsigned int));

	if (!wsaved) {
		err |= copy_in_user((u32 __user *)sf,
				    (u32 __user *)(regs->u_regs[UREG_FP]),
				    sizeof(struct reg_window32));
	} else {
		struct reg_window *rp;

		rp = &current_thread_info()->reg_window[wsaved - 1];
		for (i = 0; i < 8; i++)
			err |= __put_user(rp->locals[i], &sf->ss.locals[i]);
		for (i = 0; i < 6; i++)
			err |= __put_user(rp->ins[i], &sf->ss.ins[i]);
		err |= __put_user(rp->ins[6], &sf->ss.fp);
		err |= __put_user(rp->ins[7], &sf->ss.callers_pc);
	}	
	if (err)
		return err;

	/* 3. signal handler back-trampoline and parameters */
	regs->u_regs[UREG_FP] = (unsigned long) sf;
	regs->u_regs[UREG_I0] = ksig->sig;
	regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
	regs->u_regs[UREG_I2] = (unsigned long) &sf->info;

	/* 4. signal handler */
	regs->tpc = (unsigned long) ksig->ka.sa.sa_handler;
	regs->tnpc = (regs->tpc + 4);
	if (test_thread_flag(TIF_32BIT)) {
		regs->tpc &= 0xffffffff;
		regs->tnpc &= 0xffffffff;
	}

	/* 5. return to kernel instructions */
	if (ksig->ka.ka_restorer) {
		regs->u_regs[UREG_I7] = (unsigned long)ksig->ka.ka_restorer;
	} else {
		unsigned long address = ((unsigned long)&(sf->insns[0]));

		regs->u_regs[UREG_I7] = (unsigned long) (&(sf->insns[0]) - 2);
	
		err  = __put_user(0x821020d8, &sf->insns[0]); /*mov __NR_sigreturn, %g1*/
		err |= __put_user(0x91d02010, &sf->insns[1]); /*t 0x10*/
		if (err)
			return err;
		flush_signal_insns(address);
	}
	return 0;
}

static int setup_rt_frame32(struct ksignal *ksig, struct pt_regs *regs,
			    sigset_t *oldset)
{
	struct rt_signal_frame32 __user *sf;
	int i, err, wsaved;
	void __user *tail;
	int sigframe_size;
	u32 psr;
	compat_sigset_t seta;

	/* 1. Make sure everything is clean */
	synchronize_user_stack();
	save_and_clear_fpu();
	
	wsaved = get_thread_wsaved();

	sigframe_size = sizeof(*sf);
	if (current_thread_info()->fpsaved[0] & FPRS_FEF)
		sigframe_size += sizeof(__siginfo_fpu_t);
	if (wsaved)
		sigframe_size += sizeof(__siginfo_rwin_t);

	sf = (struct rt_signal_frame32 __user *)
		get_sigframe(ksig, regs, sigframe_size);
	
	if (invalid_frame_pointer(sf, sigframe_size)) {
		do_exit(SIGILL);
		return -EINVAL;
	}

	tail = (sf + 1);

	/* 2. Save the current process state */
	if (test_thread_flag(TIF_32BIT)) {
		regs->tpc &= 0xffffffff;
		regs->tnpc &= 0xffffffff;
	}
	err  = put_user(regs->tpc, &sf->regs.pc);
	err |= __put_user(regs->tnpc, &sf->regs.npc);
	err |= __put_user(regs->y, &sf->regs.y);
	psr = tstate_to_psr(regs->tstate);
	if (current_thread_info()->fpsaved[0] & FPRS_FEF)
		psr |= PSR_EF;
	err |= __put_user(psr, &sf->regs.psr);
	for (i = 0; i < 16; i++)
		err |= __put_user(regs->u_regs[i], &sf->regs.u_regs[i]);
	err |= __put_user(sizeof(siginfo_extra_v8plus_t), &sf->extra_size);
	err |= __put_user(SIGINFO_EXTRA_V8PLUS_MAGIC, &sf->v8plus.g_upper[0]);
	for (i = 1; i < 16; i++)
		err |= __put_user(((u32 *)regs->u_regs)[2*i],
				  &sf->v8plus.g_upper[i]);
	err |= __put_user((regs->tstate & TSTATE_ASI) >> 24UL,
			  &sf->v8plus.asi);

	if (psr & PSR_EF) {
		__siginfo_fpu_t __user *fp = tail;
		tail += sizeof(*fp);
		err |= save_fpu_state(regs, fp);
		err |= __put_user((u64)fp, &sf->fpu_save);
	} else {
		err |= __put_user(0, &sf->fpu_save);
	}
	if (wsaved) {
		__siginfo_rwin_t __user *rwp = tail;
		tail += sizeof(*rwp);
		err |= save_rwin_state(wsaved, rwp);
		err |= __put_user((u64)rwp, &sf->rwin_save);
		set_thread_wsaved(0);
	} else {
		err |= __put_user(0, &sf->rwin_save);
	}

	/* Update the siginfo structure.  */
	err |= copy_siginfo_to_user32(&sf->info, &ksig->info);
	
	/* Setup sigaltstack */
	err |= __compat_save_altstack(&sf->stack, regs->u_regs[UREG_FP]);

	seta.sig[1] = (oldset->sig[0] >> 32);
	seta.sig[0] = oldset->sig[0];
	err |= __copy_to_user(&sf->mask, &seta, sizeof(compat_sigset_t));

	if (!wsaved) {
		err |= copy_in_user((u32 __user *)sf,
				    (u32 __user *)(regs->u_regs[UREG_FP]),
				    sizeof(struct reg_window32));
	} else {
		struct reg_window *rp;

		rp = &current_thread_info()->reg_window[wsaved - 1];
		for (i = 0; i < 8; i++)
			err |= __put_user(rp->locals[i], &sf->ss.locals[i]);
		for (i = 0; i < 6; i++)
			err |= __put_user(rp->ins[i], &sf->ss.ins[i]);
		err |= __put_user(rp->ins[6], &sf->ss.fp);
		err |= __put_user(rp->ins[7], &sf->ss.callers_pc);
	}
	if (err)
		return err;
	
	/* 3. signal handler back-trampoline and parameters */
	regs->u_regs[UREG_FP] = (unsigned long) sf;
	regs->u_regs[UREG_I0] = ksig->sig;
	regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
	regs->u_regs[UREG_I2] = (unsigned long) &sf->regs;

	/* 4. signal handler */
	regs->tpc = (unsigned long) ksig->ka.sa.sa_handler;
	regs->tnpc = (regs->tpc + 4);
	if (test_thread_flag(TIF_32BIT)) {
		regs->tpc &= 0xffffffff;
		regs->tnpc &= 0xffffffff;
	}

	/* 5. return to kernel instructions */
	if (ksig->ka.ka_restorer)
		regs->u_regs[UREG_I7] = (unsigned long)ksig->ka.ka_restorer;
	else {
		unsigned long address = ((unsigned long)&(sf->insns[0]));

		regs->u_regs[UREG_I7] = (unsigned long) (&(sf->insns[0]) - 2);
	
		/* mov __NR_rt_sigreturn, %g1 */
		err |= __put_user(0x82102065, &sf->insns[0]);

		/* t 0x10 */
		err |= __put_user(0x91d02010, &sf->insns[1]);
		if (err)
			return err;

		flush_signal_insns(address);
	}
	return 0;
}

static inline void handle_signal32(struct ksignal *ksig, 
				  struct pt_regs *regs)
{
	sigset_t *oldset = sigmask_to_save();
	int err;

	if (ksig->ka.sa.sa_flags & SA_SIGINFO)
		err = setup_rt_frame32(ksig, regs, oldset);
	else
		err = setup_frame32(ksig, regs, oldset);

	signal_setup_done(err, ksig, 0);
}

static inline void syscall_restart32(unsigned long orig_i0, struct pt_regs *regs,
				     struct sigaction *sa)
{
	switch (regs->u_regs[UREG_I0]) {
	case ERESTART_RESTARTBLOCK:
	case ERESTARTNOHAND:
	no_system_call_restart:
		regs->u_regs[UREG_I0] = EINTR;
		regs->tstate |= TSTATE_ICARRY;
		break;
	case ERESTARTSYS:
		if (!(sa->sa_flags & SA_RESTART))
			goto no_system_call_restart;
		/* fallthrough */
	case ERESTARTNOINTR:
		regs->u_regs[UREG_I0] = orig_i0;
		regs->tpc -= 4;
		regs->tnpc -= 4;
	}
}

/* Note that 'init' is a special process: it doesn't get signals it doesn't
 * want to handle. Thus you cannot kill init even with a SIGKILL even by
 * mistake.
 */
void do_signal32(struct pt_regs * regs)
{
	struct ksignal ksig;
	unsigned long orig_i0 = 0;
	int restart_syscall = 0;
	bool has_handler = get_signal(&ksig);

	if (pt_regs_is_syscall(regs) &&
	    (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
		restart_syscall = 1;
		orig_i0 = regs->u_regs[UREG_G6];
	}

	if (has_handler) {
		if (restart_syscall)
			syscall_restart32(orig_i0, regs, &ksig.ka.sa);
		handle_signal32(&ksig, regs);
	} else {
		if (restart_syscall) {
			switch (regs->u_regs[UREG_I0]) {
			case ERESTARTNOHAND:
	     		case ERESTARTSYS:
			case ERESTARTNOINTR:
				/* replay the system call when we are done */
				regs->u_regs[UREG_I0] = orig_i0;
				regs->tpc -= 4;
				regs->tnpc -= 4;
				pt_regs_clear_syscall(regs);
			case ERESTART_RESTARTBLOCK:
				regs->u_regs[UREG_G1] = __NR_restart_syscall;
				regs->tpc -= 4;
				regs->tnpc -= 4;
				pt_regs_clear_syscall(regs);
			}
		}
		restore_saved_sigmask();
	}
}

struct sigstack32 {
	u32 the_stack;
	int cur_status;
};

asmlinkage int do_sys32_sigstack(u32 u_ssptr, u32 u_ossptr, unsigned long sp)
{
	struct sigstack32 __user *ssptr =
		(struct sigstack32 __user *)((unsigned long)(u_ssptr));
	struct sigstack32 __user *ossptr =
		(struct sigstack32 __user *)((unsigned long)(u_ossptr));
	int ret = -EFAULT;

	/* First see if old state is wanted. */
	if (ossptr) {
		if (put_user(current->sas_ss_sp + current->sas_ss_size,
			     &ossptr->the_stack) ||
		    __put_user(on_sig_stack(sp), &ossptr->cur_status))
			goto out;
	}
	
	/* Now see if we want to update the new state. */
	if (ssptr) {
		u32 ss_sp;

		if (get_user(ss_sp, &ssptr->the_stack))
			goto out;

		/* If the current stack was set with sigaltstack, don't
		 * swap stacks while we are on it.
		 */
		ret = -EPERM;
		if (current->sas_ss_sp && on_sig_stack(sp))
			goto out;
			
		/* Since we don't know the extent of the stack, and we don't
		 * track onstack-ness, but rather calculate it, we must
		 * presume a size.  Ho hum this interface is lossy.
		 */
		current->sas_ss_sp = (unsigned long)ss_sp - SIGSTKSZ;
		current->sas_ss_size = SIGSTKSZ;
	}
	
	ret = 0;
out:
	return ret;
}