summaryrefslogtreecommitdiffstats
path: root/arch/s390/kernel/entry64.S
blob: 2b2188b97c6aff464e467b7250823257924e31ab (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
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
/*
 *    S390 low-level entry points.
 *
 *    Copyright IBM Corp. 1999, 2012
 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
 *		 Hartmut Penner (hp@de.ibm.com),
 *		 Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
 *		 Heiko Carstens <heiko.carstens@de.ibm.com>
 */

#include <linux/init.h>
#include <linux/linkage.h>
#include <asm/processor.h>
#include <asm/cache.h>
#include <asm/errno.h>
#include <asm/ptrace.h>
#include <asm/thread_info.h>
#include <asm/asm-offsets.h>
#include <asm/unistd.h>
#include <asm/page.h>
#include <asm/sigp.h>
#include <asm/irq.h>

__PT_R0      =	__PT_GPRS
__PT_R1      =	__PT_GPRS + 8
__PT_R2      =	__PT_GPRS + 16
__PT_R3      =	__PT_GPRS + 24
__PT_R4      =	__PT_GPRS + 32
__PT_R5      =	__PT_GPRS + 40
__PT_R6      =	__PT_GPRS + 48
__PT_R7      =	__PT_GPRS + 56
__PT_R8      =	__PT_GPRS + 64
__PT_R9      =	__PT_GPRS + 72
__PT_R10     =	__PT_GPRS + 80
__PT_R11     =	__PT_GPRS + 88
__PT_R12     =	__PT_GPRS + 96
__PT_R13     =	__PT_GPRS + 104
__PT_R14     =	__PT_GPRS + 112
__PT_R15     =	__PT_GPRS + 120

STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
STACK_SIZE  = 1 << STACK_SHIFT
STACK_INIT = STACK_SIZE - STACK_FRAME_OVERHEAD - __PT_SIZE

_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
		 _TIF_MCCK_PENDING | _TIF_PER_TRAP )
_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
		 _TIF_MCCK_PENDING)
_TIF_TRACE    = (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | \
		 _TIF_SYSCALL_TRACEPOINT)

#define BASED(name) name-system_call(%r13)

	.macro	TRACE_IRQS_ON
#ifdef CONFIG_TRACE_IRQFLAGS
	basr	%r2,%r0
	brasl	%r14,trace_hardirqs_on_caller
#endif
	.endm

	.macro	TRACE_IRQS_OFF
#ifdef CONFIG_TRACE_IRQFLAGS
	basr	%r2,%r0
	brasl	%r14,trace_hardirqs_off_caller
#endif
	.endm

	.macro	LOCKDEP_SYS_EXIT
#ifdef CONFIG_LOCKDEP
	tm	__PT_PSW+1(%r11),0x01	# returning to user ?
	jz	.+10
	brasl	%r14,lockdep_sys_exit
#endif
	.endm

	.macro LPP newpp
#if defined(CONFIG_KVM) || defined(CONFIG_KVM_MODULE)
	tm	__LC_MACHINE_FLAGS+6,0x20	# MACHINE_FLAG_LPP
	jz	.+8
	.insn	s,0xb2800000,\newpp
#endif
	.endm

	.macro	HANDLE_SIE_INTERCEPT scratch,reason
#if defined(CONFIG_KVM) || defined(CONFIG_KVM_MODULE)
	tmhh	%r8,0x0001		# interrupting from user ?
	jnz	.+62
	lgr	\scratch,%r9
	slg	\scratch,BASED(.Lsie_critical)
	clg	\scratch,BASED(.Lsie_critical_length)
	.if	\reason==1
	# Some program interrupts are suppressing (e.g. protection).
	# We must also check the instruction after SIE in that case.
	# do_protection_exception will rewind to rewind_pad
	jh	.+42
	.else
	jhe	.+42
	.endif
	lg	%r14,__SF_EMPTY(%r15)		# get control block pointer
	LPP	__SF_EMPTY+16(%r15)		# set host id
	ni	__SIE_PROG0C+3(%r14),0xfe	# no longer in SIE
	lctlg	%c1,%c1,__LC_USER_ASCE		# load primary asce
	larl	%r9,sie_exit			# skip forward to sie_exit
	mvi	__SF_EMPTY+31(%r15),\reason	# set exit reason
#endif
	.endm

	.macro	CHECK_STACK stacksize,savearea
#ifdef CONFIG_CHECK_STACK
	tml	%r15,\stacksize - CONFIG_STACK_GUARD
	lghi	%r14,\savearea
	jz	stack_overflow
#endif
	.endm

	.macro	SWITCH_ASYNC savearea,stack,shift
	tmhh	%r8,0x0001		# interrupting from user ?
	jnz	1f
	lgr	%r14,%r9
	slg	%r14,BASED(.Lcritical_start)
	clg	%r14,BASED(.Lcritical_length)
	jhe	0f
	lghi	%r11,\savearea		# inside critical section, do cleanup
	brasl	%r14,cleanup_critical
	tmhh	%r8,0x0001		# retest problem state after cleanup
	jnz	1f
0:	lg	%r14,\stack		# are we already on the target stack?
	slgr	%r14,%r15
	srag	%r14,%r14,\shift
	jnz	1f
	CHECK_STACK 1<<\shift,\savearea
	aghi	%r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
	j	2f
1:	lg	%r15,\stack		# load target stack
2:	la	%r11,STACK_FRAME_OVERHEAD(%r15)
	.endm

	.macro UPDATE_VTIME scratch,enter_timer
	lg	\scratch,__LC_EXIT_TIMER
	slg	\scratch,\enter_timer
	alg	\scratch,__LC_USER_TIMER
	stg	\scratch,__LC_USER_TIMER
	lg	\scratch,__LC_LAST_UPDATE_TIMER
	slg	\scratch,__LC_EXIT_TIMER
	alg	\scratch,__LC_SYSTEM_TIMER
	stg	\scratch,__LC_SYSTEM_TIMER
	mvc	__LC_LAST_UPDATE_TIMER(8),\enter_timer
	.endm

	.macro	LAST_BREAK scratch
	srag	\scratch,%r10,23
	jz	.+10
	stg	%r10,__TI_last_break(%r12)
	.endm

	.macro REENABLE_IRQS
	stg	%r8,__LC_RETURN_PSW
	ni	__LC_RETURN_PSW,0xbf
	ssm	__LC_RETURN_PSW
	.endm

	.macro STCK savearea
#ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
	.insn	s,0xb27c0000,\savearea		# store clock fast
#else
	.insn	s,0xb2050000,\savearea		# store clock
#endif
	.endm

	.section .kprobes.text, "ax"

/*
 * Scheduler resume function, called by switch_to
 *  gpr2 = (task_struct *) prev
 *  gpr3 = (task_struct *) next
 * Returns:
 *  gpr2 = prev
 */
ENTRY(__switch_to)
	stmg	%r6,%r15,__SF_GPRS(%r15)	# store gprs of prev task
	stg	%r15,__THREAD_ksp(%r2)		# store kernel stack of prev
	lg	%r4,__THREAD_info(%r2)		# get thread_info of prev
	lg	%r5,__THREAD_info(%r3)		# get thread_info of next
	lgr	%r15,%r5
	aghi	%r15,STACK_INIT			# end of kernel stack of next
	stg	%r3,__LC_CURRENT		# store task struct of next
	stg	%r5,__LC_THREAD_INFO		# store thread info of next
	stg	%r15,__LC_KERNEL_STACK		# store end of kernel stack
	lctl	%c4,%c4,__TASK_pid(%r3)		# load pid to control reg. 4
	mvc	__LC_CURRENT_PID+4(4,%r0),__TASK_pid(%r3) # store pid of next
	lg	%r15,__THREAD_ksp(%r3)		# load kernel stack of next
	tm	__TI_flags+7(%r4),_TIF_MCCK_PENDING # machine check pending?
	jz	0f
	ni	__TI_flags+7(%r4),255-_TIF_MCCK_PENDING	# clear flag in prev
	oi	__TI_flags+7(%r5),_TIF_MCCK_PENDING	# set it in next
0:	lmg	%r6,%r15,__SF_GPRS(%r15)	# load gprs of next task
	br	%r14

__critical_start:
/*
 * SVC interrupt handler routine. System calls are synchronous events and
 * are executed with interrupts enabled.
 */

ENTRY(system_call)
	stpt	__LC_SYNC_ENTER_TIMER
sysc_stmg:
	stmg	%r8,%r15,__LC_SAVE_AREA_SYNC
	lg	%r10,__LC_LAST_BREAK
	lg	%r12,__LC_THREAD_INFO
sysc_per:
	lg	%r15,__LC_KERNEL_STACK
	la	%r11,STACK_FRAME_OVERHEAD(%r15)	# pointer to pt_regs
sysc_vtime:
	UPDATE_VTIME %r13,__LC_SYNC_ENTER_TIMER
	LAST_BREAK %r13
	stmg	%r0,%r7,__PT_R0(%r11)
	mvc	__PT_R8(64,%r11),__LC_SAVE_AREA_SYNC
	mvc	__PT_PSW(16,%r11),__LC_SVC_OLD_PSW
	mvc	__PT_INT_CODE(4,%r11),__LC_SVC_ILC
sysc_do_svc:
	oi	__TI_flags+7(%r12),_TIF_SYSCALL
	lg	%r10,__TI_sysc_table(%r12)	# address of system call table
	llgh	%r8,__PT_INT_CODE+2(%r11)
	slag	%r8,%r8,2			# shift and test for svc 0
	jnz	sysc_nr_ok
	# svc 0: system call number in %r1
	llgfr	%r1,%r1				# clear high word in r1
	cghi	%r1,NR_syscalls
	jnl	sysc_nr_ok
	sth	%r1,__PT_INT_CODE+2(%r11)
	slag	%r8,%r1,2
sysc_nr_ok:
	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
	stg	%r2,__PT_ORIG_GPR2(%r11)
	stg	%r7,STACK_FRAME_OVERHEAD(%r15)
	lgf	%r9,0(%r8,%r10)			# get system call add.
	tm	__TI_flags+6(%r12),_TIF_TRACE >> 8
	jnz	sysc_tracesys
	basr	%r14,%r9			# call sys_xxxx
	stg	%r2,__PT_R2(%r11)		# store return value

sysc_return:
	LOCKDEP_SYS_EXIT
sysc_tif:
	tm	__PT_PSW+1(%r11),0x01		# returning to user ?
	jno	sysc_restore
	tm	__TI_flags+7(%r12),_TIF_WORK_SVC
	jnz	sysc_work			# check for work
	ni	__TI_flags+7(%r12),255-_TIF_SYSCALL
sysc_restore:
	lg	%r14,__LC_VDSO_PER_CPU
	lmg	%r0,%r10,__PT_R0(%r11)
	mvc	__LC_RETURN_PSW(16),__PT_PSW(%r11)
	stpt	__LC_EXIT_TIMER
	mvc	__VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER
	lmg	%r11,%r15,__PT_R11(%r11)
	lpswe	__LC_RETURN_PSW
sysc_done:

#
# One of the work bits is on. Find out which one.
#
sysc_work:
	tm	__TI_flags+7(%r12),_TIF_MCCK_PENDING
	jo	sysc_mcck_pending
	tm	__TI_flags+7(%r12),_TIF_NEED_RESCHED
	jo	sysc_reschedule
	tm	__TI_flags+7(%r12),_TIF_PER_TRAP
	jo	sysc_singlestep
	tm	__TI_flags+7(%r12),_TIF_SIGPENDING
	jo	sysc_sigpending
	tm	__TI_flags+7(%r12),_TIF_NOTIFY_RESUME
	jo	sysc_notify_resume
	j	sysc_return		# beware of critical section cleanup

#
# _TIF_NEED_RESCHED is set, call schedule
#
sysc_reschedule:
	larl	%r14,sysc_return
	jg	schedule

#
# _TIF_MCCK_PENDING is set, call handler
#
sysc_mcck_pending:
	larl	%r14,sysc_return
	jg	s390_handle_mcck	# TIF bit will be cleared by handler

#
# _TIF_SIGPENDING is set, call do_signal
#
sysc_sigpending:
	lgr	%r2,%r11		# pass pointer to pt_regs
	brasl	%r14,do_signal
	tm	__TI_flags+7(%r12),_TIF_SYSCALL
	jno	sysc_return
	lmg	%r2,%r7,__PT_R2(%r11)	# load svc arguments
	lghi	%r8,0			# svc 0 returns -ENOSYS
	llgh	%r1,__PT_INT_CODE+2(%r11)	# load new svc number
	cghi	%r1,NR_syscalls
	jnl	sysc_nr_ok		# invalid svc number -> do svc 0
	slag	%r8,%r1,2
	j	sysc_nr_ok		# restart svc

#
# _TIF_NOTIFY_RESUME is set, call do_notify_resume
#
sysc_notify_resume:
	lgr	%r2,%r11		# pass pointer to pt_regs
	larl	%r14,sysc_return
	jg	do_notify_resume

#
# _TIF_PER_TRAP is set, call do_per_trap
#
sysc_singlestep:
	ni	__TI_flags+7(%r12),255-_TIF_PER_TRAP
	lgr	%r2,%r11		# pass pointer to pt_regs
	larl	%r14,sysc_return
	jg	do_per_trap

#
# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
# and after the system call
#
sysc_tracesys:
	lgr	%r2,%r11		# pass pointer to pt_regs
	la	%r3,0
	llgh	%r0,__PT_INT_CODE+2(%r11)
	stg	%r0,__PT_R2(%r11)
	brasl	%r14,do_syscall_trace_enter
	lghi	%r0,NR_syscalls
	clgr	%r0,%r2
	jnh	sysc_tracenogo
	sllg	%r8,%r2,2
	lgf	%r9,0(%r8,%r10)
sysc_tracego:
	lmg	%r3,%r7,__PT_R3(%r11)
	stg	%r7,STACK_FRAME_OVERHEAD(%r15)
	lg	%r2,__PT_ORIG_GPR2(%r11)
	basr	%r14,%r9		# call sys_xxx
	stg	%r2,__PT_R2(%r11)	# store return value
sysc_tracenogo:
	tm	__TI_flags+6(%r12),_TIF_TRACE >> 8
	jz	sysc_return
	lgr	%r2,%r11		# pass pointer to pt_regs
	larl	%r14,sysc_return
	jg	do_syscall_trace_exit

#
# a new process exits the kernel with ret_from_fork
#
ENTRY(ret_from_fork)
	la	%r11,STACK_FRAME_OVERHEAD(%r15)
	lg	%r12,__LC_THREAD_INFO
	brasl	%r14,schedule_tail
	TRACE_IRQS_ON
	ssm	__LC_SVC_NEW_PSW	# reenable interrupts
	tm	__PT_PSW+1(%r11),0x01	# forking a kernel thread ?
	jne	sysc_tracenogo
	# it's a kernel thread
	lmg	%r9,%r10,__PT_R9(%r11)	# load gprs
ENTRY(kernel_thread_starter)
	la	%r2,0(%r10)
	basr	%r14,%r9
	j	sysc_tracenogo

/*
 * Program check handler routine
 */

ENTRY(pgm_check_handler)
	stpt	__LC_SYNC_ENTER_TIMER
	stmg	%r8,%r15,__LC_SAVE_AREA_SYNC
	lg	%r10,__LC_LAST_BREAK
	lg	%r12,__LC_THREAD_INFO
	larl	%r13,system_call
	lmg	%r8,%r9,__LC_PGM_OLD_PSW
	HANDLE_SIE_INTERCEPT %r14,1
	tmhh	%r8,0x0001		# test problem state bit
	jnz	1f			# -> fault in user space
	tmhh	%r8,0x4000		# PER bit set in old PSW ?
	jnz	0f			# -> enabled, can't be a double fault
	tm	__LC_PGM_ILC+3,0x80	# check for per exception
	jnz	pgm_svcper		# -> single stepped svc
0:	CHECK_STACK STACK_SIZE,__LC_SAVE_AREA_SYNC
	aghi	%r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
	j	2f
1:	UPDATE_VTIME %r14,__LC_SYNC_ENTER_TIMER
	LAST_BREAK %r14
	lg	%r15,__LC_KERNEL_STACK
	lg	%r14,__TI_task(%r12)
	lghi	%r13,__LC_PGM_TDB
	tm	__LC_PGM_ILC+2,0x02	# check for transaction abort
	jz	2f
	mvc	__THREAD_trap_tdb(256,%r14),0(%r13)
2:	la	%r11,STACK_FRAME_OVERHEAD(%r15)
	stmg	%r0,%r7,__PT_R0(%r11)
	mvc	__PT_R8(64,%r11),__LC_SAVE_AREA_SYNC
	stmg	%r8,%r9,__PT_PSW(%r11)
	mvc	__PT_INT_CODE(4,%r11),__LC_PGM_ILC
	mvc	__PT_INT_PARM_LONG(8,%r11),__LC_TRANS_EXC_CODE
	stg	%r10,__PT_ARGS(%r11)
	tm	__LC_PGM_ILC+3,0x80	# check for per exception
	jz	0f
	tmhh	%r8,0x0001		# kernel per event ?
	jz	pgm_kprobe
	oi	__TI_flags+7(%r12),_TIF_PER_TRAP
	mvc	__THREAD_per_address(8,%r14),__LC_PER_ADDRESS
	mvc	__THREAD_per_cause(2,%r14),__LC_PER_CAUSE
	mvc	__THREAD_per_paid(1,%r14),__LC_PER_PAID
0:	REENABLE_IRQS
	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
	larl	%r1,pgm_check_table
	llgh	%r10,__PT_INT_CODE+2(%r11)
	nill	%r10,0x007f
	sll	%r10,2
	je	sysc_return
	lgf	%r1,0(%r10,%r1)		# load address of handler routine
	lgr	%r2,%r11		# pass pointer to pt_regs
	basr	%r14,%r1		# branch to interrupt-handler
	j	sysc_return

#
# PER event in supervisor state, must be kprobes
#
pgm_kprobe:
	REENABLE_IRQS
	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
	lgr	%r2,%r11		# pass pointer to pt_regs
	brasl	%r14,do_per_trap
	j	sysc_return

#
# single stepped system call
#
pgm_svcper:
	oi	__TI_flags+7(%r12),_TIF_PER_TRAP
	mvc	__LC_RETURN_PSW(8),__LC_SVC_NEW_PSW
	larl	%r14,sysc_per
	stg	%r14,__LC_RETURN_PSW+8
	lpswe	__LC_RETURN_PSW		# branch to sysc_per and enable irqs

/*
 * IO interrupt handler routine
 */
ENTRY(io_int_handler)
	STCK	__LC_INT_CLOCK
	stpt	__LC_ASYNC_ENTER_TIMER
	stmg	%r8,%r15,__LC_SAVE_AREA_ASYNC
	lg	%r10,__LC_LAST_BREAK
	lg	%r12,__LC_THREAD_INFO
	larl	%r13,system_call
	lmg	%r8,%r9,__LC_IO_OLD_PSW
	HANDLE_SIE_INTERCEPT %r14,2
	SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT
	tmhh	%r8,0x0001		# interrupting from user?
	jz	io_skip
	UPDATE_VTIME %r14,__LC_ASYNC_ENTER_TIMER
	LAST_BREAK %r14
io_skip:
	stmg	%r0,%r7,__PT_R0(%r11)
	mvc	__PT_R8(64,%r11),__LC_SAVE_AREA_ASYNC
	stmg	%r8,%r9,__PT_PSW(%r11)
	mvc	__PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID
	TRACE_IRQS_OFF
	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
io_loop:
	lgr	%r2,%r11		# pass pointer to pt_regs
	lghi	%r3,IO_INTERRUPT
	tm	__PT_INT_CODE+8(%r11),0x80	# adapter interrupt ?
	jz	io_call
	lghi	%r3,THIN_INTERRUPT
io_call:
	brasl	%r14,do_IRQ
	tm	__LC_MACHINE_FLAGS+6,0x10	# MACHINE_FLAG_LPAR
	jz	io_return
	tpi	0
	jz	io_return
	mvc	__PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID
	j	io_loop
io_return:
	LOCKDEP_SYS_EXIT
	TRACE_IRQS_ON
io_tif:
	tm	__TI_flags+7(%r12),_TIF_WORK_INT
	jnz	io_work 		# there is work to do (signals etc.)
io_restore:
	lg	%r14,__LC_VDSO_PER_CPU
	lmg	%r0,%r10,__PT_R0(%r11)
	mvc	__LC_RETURN_PSW(16),__PT_PSW(%r11)
	stpt	__LC_EXIT_TIMER
	mvc	__VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER
	lmg	%r11,%r15,__PT_R11(%r11)
	lpswe	__LC_RETURN_PSW
io_done:

#
# There is work todo, find out in which context we have been interrupted:
# 1) if we return to user space we can do all _TIF_WORK_INT work
# 2) if we return to kernel code and kvm is enabled check if we need to
#    modify the psw to leave SIE
# 3) if we return to kernel code and preemptive scheduling is enabled check
#    the preemption counter and if it is zero call preempt_schedule_irq
# Before any work can be done, a switch to the kernel stack is required.
#
io_work:
	tm	__PT_PSW+1(%r11),0x01	# returning to user ?
	jo	io_work_user		# yes -> do resched & signal
#ifdef CONFIG_PREEMPT
	# check for preemptive scheduling
	icm	%r0,15,__TI_precount(%r12)
	jnz	io_restore		# preemption is disabled
	tm	__TI_flags+7(%r12),_TIF_NEED_RESCHED
	jno	io_restore
	# switch to kernel stack
	lg	%r1,__PT_R15(%r11)
	aghi	%r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
	mvc	STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
	xc	__SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1)
	la	%r11,STACK_FRAME_OVERHEAD(%r1)
	lgr	%r15,%r1
	# TRACE_IRQS_ON already done at io_return, call
	# TRACE_IRQS_OFF to keep things symmetrical
	TRACE_IRQS_OFF
	brasl	%r14,preempt_schedule_irq
	j	io_return
#else
	j	io_restore
#endif

#
# Need to do work before returning to userspace, switch to kernel stack
#
io_work_user:
	lg	%r1,__LC_KERNEL_STACK
	mvc	STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
	xc	__SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1)
	la	%r11,STACK_FRAME_OVERHEAD(%r1)
	lgr	%r15,%r1

#
# One of the work bits is on. Find out which one.
# Checked are: _TIF_SIGPENDING, _TIF_NOTIFY_RESUME, _TIF_NEED_RESCHED
#	       and _TIF_MCCK_PENDING
#
io_work_tif:
	tm	__TI_flags+7(%r12),_TIF_MCCK_PENDING
	jo	io_mcck_pending
	tm	__TI_flags+7(%r12),_TIF_NEED_RESCHED
	jo	io_reschedule
	tm	__TI_flags+7(%r12),_TIF_SIGPENDING
	jo	io_sigpending
	tm	__TI_flags+7(%r12),_TIF_NOTIFY_RESUME
	jo	io_notify_resume
	j	io_return		# beware of critical section cleanup

#
# _TIF_MCCK_PENDING is set, call handler
#
io_mcck_pending:
	# TRACE_IRQS_ON already done at io_return
	brasl	%r14,s390_handle_mcck	# TIF bit will be cleared by handler
	TRACE_IRQS_OFF
	j	io_return

#
# _TIF_NEED_RESCHED is set, call schedule
#
io_reschedule:
	# TRACE_IRQS_ON already done at io_return
	ssm	__LC_SVC_NEW_PSW	# reenable interrupts
	brasl	%r14,schedule		# call scheduler
	ssm	__LC_PGM_NEW_PSW	# disable I/O and ext. interrupts
	TRACE_IRQS_OFF
	j	io_return

#
# _TIF_SIGPENDING or is set, call do_signal
#
io_sigpending:
	# TRACE_IRQS_ON already done at io_return
	ssm	__LC_SVC_NEW_PSW	# reenable interrupts
	lgr	%r2,%r11		# pass pointer to pt_regs
	brasl	%r14,do_signal
	ssm	__LC_PGM_NEW_PSW	# disable I/O and ext. interrupts
	TRACE_IRQS_OFF
	j	io_return

#
# _TIF_NOTIFY_RESUME or is set, call do_notify_resume
#
io_notify_resume:
	# TRACE_IRQS_ON already done at io_return
	ssm	__LC_SVC_NEW_PSW	# reenable interrupts
	lgr	%r2,%r11		# pass pointer to pt_regs
	brasl	%r14,do_notify_resume
	ssm	__LC_PGM_NEW_PSW	# disable I/O and ext. interrupts
	TRACE_IRQS_OFF
	j	io_return

/*
 * External interrupt handler routine
 */
ENTRY(ext_int_handler)
	STCK	__LC_INT_CLOCK
	stpt	__LC_ASYNC_ENTER_TIMER
	stmg	%r8,%r15,__LC_SAVE_AREA_ASYNC
	lg	%r10,__LC_LAST_BREAK
	lg	%r12,__LC_THREAD_INFO
	larl	%r13,system_call
	lmg	%r8,%r9,__LC_EXT_OLD_PSW
	HANDLE_SIE_INTERCEPT %r14,3
	SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT
	tmhh	%r8,0x0001		# interrupting from user ?
	jz	ext_skip
	UPDATE_VTIME %r14,__LC_ASYNC_ENTER_TIMER
	LAST_BREAK %r14
ext_skip:
	stmg	%r0,%r7,__PT_R0(%r11)
	mvc	__PT_R8(64,%r11),__LC_SAVE_AREA_ASYNC
	stmg	%r8,%r9,__PT_PSW(%r11)
	lghi	%r1,__LC_EXT_PARAMS2
	mvc	__PT_INT_CODE(4,%r11),__LC_EXT_CPU_ADDR
	mvc	__PT_INT_PARM(4,%r11),__LC_EXT_PARAMS
	mvc	__PT_INT_PARM_LONG(8,%r11),0(%r1)
	TRACE_IRQS_OFF
	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
	lgr	%r2,%r11		# pass pointer to pt_regs
	lghi	%r3,EXT_INTERRUPT
	brasl	%r14,do_IRQ
	j	io_return

/*
 * Load idle PSW. The second "half" of this function is in cleanup_idle.
 */
ENTRY(psw_idle)
	stg	%r3,__SF_EMPTY(%r15)
	larl	%r1,psw_idle_lpsw+4
	stg	%r1,__SF_EMPTY+8(%r15)
	STCK	__CLOCK_IDLE_ENTER(%r2)
	stpt	__TIMER_IDLE_ENTER(%r2)
psw_idle_lpsw:
	lpswe	__SF_EMPTY(%r15)
	br	%r14
psw_idle_end:

__critical_end:

/*
 * Machine check handler routines
 */
ENTRY(mcck_int_handler)
	STCK	__LC_MCCK_CLOCK
	la	%r1,4095		# revalidate r1
	spt	__LC_CPU_TIMER_SAVE_AREA-4095(%r1)	# revalidate cpu timer
	lmg	%r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r1)# revalidate gprs
	lg	%r10,__LC_LAST_BREAK
	lg	%r12,__LC_THREAD_INFO
	larl	%r13,system_call
	lmg	%r8,%r9,__LC_MCK_OLD_PSW
	HANDLE_SIE_INTERCEPT %r14,4
	tm	__LC_MCCK_CODE,0x80	# system damage?
	jo	mcck_panic		# yes -> rest of mcck code invalid
	lghi	%r14,__LC_CPU_TIMER_SAVE_AREA
	mvc	__LC_MCCK_ENTER_TIMER(8),0(%r14)
	tm	__LC_MCCK_CODE+5,0x02	# stored cpu timer value valid?
	jo	3f
	la	%r14,__LC_SYNC_ENTER_TIMER
	clc	0(8,%r14),__LC_ASYNC_ENTER_TIMER
	jl	0f
	la	%r14,__LC_ASYNC_ENTER_TIMER
0:	clc	0(8,%r14),__LC_EXIT_TIMER
	jl	1f
	la	%r14,__LC_EXIT_TIMER
1:	clc	0(8,%r14),__LC_LAST_UPDATE_TIMER
	jl	2f
	la	%r14,__LC_LAST_UPDATE_TIMER
2:	spt	0(%r14)
	mvc	__LC_MCCK_ENTER_TIMER(8),0(%r14)
3:	tm	__LC_MCCK_CODE+2,0x09	# mwp + ia of old psw valid?
	jno	mcck_panic		# no -> skip cleanup critical
	SWITCH_ASYNC __LC_GPREGS_SAVE_AREA+64,__LC_PANIC_STACK,PAGE_SHIFT
	tm	%r8,0x0001		# interrupting from user ?
	jz	mcck_skip
	UPDATE_VTIME %r14,__LC_MCCK_ENTER_TIMER
	LAST_BREAK %r14
mcck_skip:
	lghi	%r14,__LC_GPREGS_SAVE_AREA+64
	stmg	%r0,%r7,__PT_R0(%r11)
	mvc	__PT_R8(64,%r11),0(%r14)
	stmg	%r8,%r9,__PT_PSW(%r11)
	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
	lgr	%r2,%r11		# pass pointer to pt_regs
	brasl	%r14,s390_do_machine_check
	tm	__PT_PSW+1(%r11),0x01	# returning to user ?
	jno	mcck_return
	lg	%r1,__LC_KERNEL_STACK	# switch to kernel stack
	mvc	STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
	xc	__SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1)
	la	%r11,STACK_FRAME_OVERHEAD(%r1)
	lgr	%r15,%r1
	ssm	__LC_PGM_NEW_PSW	# turn dat on, keep irqs off
	tm	__TI_flags+7(%r12),_TIF_MCCK_PENDING
	jno	mcck_return
	TRACE_IRQS_OFF
	brasl	%r14,s390_handle_mcck
	TRACE_IRQS_ON
mcck_return:
	lg	%r14,__LC_VDSO_PER_CPU
	lmg	%r0,%r10,__PT_R0(%r11)
	mvc	__LC_RETURN_MCCK_PSW(16),__PT_PSW(%r11) # move return PSW
	tm	__LC_RETURN_MCCK_PSW+1,0x01 # returning to user ?
	jno	0f
	stpt	__LC_EXIT_TIMER
	mvc	__VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER
0:	lmg	%r11,%r15,__PT_R11(%r11)
	lpswe	__LC_RETURN_MCCK_PSW

mcck_panic:
	lg	%r14,__LC_PANIC_STACK
	slgr	%r14,%r15
	srag	%r14,%r14,PAGE_SHIFT
	jz	0f
	lg	%r15,__LC_PANIC_STACK
0:	aghi	%r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
	j	mcck_skip

#
# PSW restart interrupt handler
#
ENTRY(restart_int_handler)
	stg	%r15,__LC_SAVE_AREA_RESTART
	lg	%r15,__LC_RESTART_STACK
	aghi	%r15,-__PT_SIZE			# create pt_regs on stack
	xc	0(__PT_SIZE,%r15),0(%r15)
	stmg	%r0,%r14,__PT_R0(%r15)
	mvc	__PT_R15(8,%r15),__LC_SAVE_AREA_RESTART
	mvc	__PT_PSW(16,%r15),__LC_RST_OLD_PSW # store restart old psw
	aghi	%r15,-STACK_FRAME_OVERHEAD	# create stack frame on stack
	xc	0(STACK_FRAME_OVERHEAD,%r15),0(%r15)
	lg	%r1,__LC_RESTART_FN		# load fn, parm & source cpu
	lg	%r2,__LC_RESTART_DATA
	lg	%r3,__LC_RESTART_SOURCE
	ltgr	%r3,%r3				# test source cpu address
	jm	1f				# negative -> skip source stop
0:	sigp	%r4,%r3,SIGP_SENSE		# sigp sense to source cpu
	brc	10,0b				# wait for status stored
1:	basr	%r14,%r1			# call function
	stap	__SF_EMPTY(%r15)		# store cpu address
	llgh	%r3,__SF_EMPTY(%r15)
2:	sigp	%r4,%r3,SIGP_STOP		# sigp stop to current cpu
	brc	2,2b
3:	j	3b

	.section .kprobes.text, "ax"

#ifdef CONFIG_CHECK_STACK
/*
 * The synchronous or the asynchronous stack overflowed. We are dead.
 * No need to properly save the registers, we are going to panic anyway.
 * Setup a pt_regs so that show_trace can provide a good call trace.
 */
stack_overflow:
	lg	%r15,__LC_PANIC_STACK	# change to panic stack
	la	%r11,STACK_FRAME_OVERHEAD(%r15)
	stmg	%r0,%r7,__PT_R0(%r11)
	stmg	%r8,%r9,__PT_PSW(%r11)
	mvc	__PT_R8(64,%r11),0(%r14)
	stg	%r10,__PT_ORIG_GPR2(%r11) # store last break to orig_gpr2
	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
	lgr	%r2,%r11		# pass pointer to pt_regs
	jg	kernel_stack_overflow
#endif

	.align	8
cleanup_table:
	.quad	system_call
	.quad	sysc_do_svc
	.quad	sysc_tif
	.quad	sysc_restore
	.quad	sysc_done
	.quad	io_tif
	.quad	io_restore
	.quad	io_done
	.quad	psw_idle
	.quad	psw_idle_end

cleanup_critical:
	clg	%r9,BASED(cleanup_table)	# system_call
	jl	0f
	clg	%r9,BASED(cleanup_table+8)	# sysc_do_svc
	jl	cleanup_system_call
	clg	%r9,BASED(cleanup_table+16)	# sysc_tif
	jl	0f
	clg	%r9,BASED(cleanup_table+24)	# sysc_restore
	jl	cleanup_sysc_tif
	clg	%r9,BASED(cleanup_table+32)	# sysc_done
	jl	cleanup_sysc_restore
	clg	%r9,BASED(cleanup_table+40)	# io_tif
	jl	0f
	clg	%r9,BASED(cleanup_table+48)	# io_restore
	jl	cleanup_io_tif
	clg	%r9,BASED(cleanup_table+56)	# io_done
	jl	cleanup_io_restore
	clg	%r9,BASED(cleanup_table+64)	# psw_idle
	jl	0f
	clg	%r9,BASED(cleanup_table+72)	# psw_idle_end
	jl	cleanup_idle
0:	br	%r14


cleanup_system_call:
	# check if stpt has been executed
	clg	%r9,BASED(cleanup_system_call_insn)
	jh	0f
	mvc	__LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER
	cghi	%r11,__LC_SAVE_AREA_ASYNC
	je	0f
	mvc	__LC_SYNC_ENTER_TIMER(8),__LC_MCCK_ENTER_TIMER
0:	# check if stmg has been executed
	clg	%r9,BASED(cleanup_system_call_insn+8)
	jh	0f
	mvc	__LC_SAVE_AREA_SYNC(64),0(%r11)
0:	# check if base register setup + TIF bit load has been done
	clg	%r9,BASED(cleanup_system_call_insn+16)
	jhe	0f
	# set up saved registers r10 and r12
	stg	%r10,16(%r11)		# r10 last break
	stg	%r12,32(%r11)		# r12 thread-info pointer
0:	# check if the user time update has been done
	clg	%r9,BASED(cleanup_system_call_insn+24)
	jh	0f
	lg	%r15,__LC_EXIT_TIMER
	slg	%r15,__LC_SYNC_ENTER_TIMER
	alg	%r15,__LC_USER_TIMER
	stg	%r15,__LC_USER_TIMER
0:	# check if the system time update has been done
	clg	%r9,BASED(cleanup_system_call_insn+32)
	jh	0f
	lg	%r15,__LC_LAST_UPDATE_TIMER
	slg	%r15,__LC_EXIT_TIMER
	alg	%r15,__LC_SYSTEM_TIMER
	stg	%r15,__LC_SYSTEM_TIMER
0:	# update accounting time stamp
	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
	# do LAST_BREAK
	lg	%r9,16(%r11)
	srag	%r9,%r9,23
	jz	0f
	mvc	__TI_last_break(8,%r12),16(%r11)
0:	# set up saved register r11
	lg	%r15,__LC_KERNEL_STACK
	la	%r9,STACK_FRAME_OVERHEAD(%r15)
	stg	%r9,24(%r11)		# r11 pt_regs pointer
	# fill pt_regs
	mvc	__PT_R8(64,%r9),__LC_SAVE_AREA_SYNC
	stmg	%r0,%r7,__PT_R0(%r9)
	mvc	__PT_PSW(16,%r9),__LC_SVC_OLD_PSW
	mvc	__PT_INT_CODE(4,%r9),__LC_SVC_ILC
	# setup saved register r15
	stg	%r15,56(%r11)		# r15 stack pointer
	# set new psw address and exit
	larl	%r9,sysc_do_svc
	br	%r14
cleanup_system_call_insn:
	.quad	system_call
	.quad	sysc_stmg
	.quad	sysc_per
	.quad	sysc_vtime+18
	.quad	sysc_vtime+42

cleanup_sysc_tif:
	larl	%r9,sysc_tif
	br	%r14

cleanup_sysc_restore:
	clg	%r9,BASED(cleanup_sysc_restore_insn)
	je	0f
	lg	%r9,24(%r11)		# get saved pointer to pt_regs
	mvc	__LC_RETURN_PSW(16),__PT_PSW(%r9)
	mvc	0(64,%r11),__PT_R8(%r9)
	lmg	%r0,%r7,__PT_R0(%r9)
0:	lmg	%r8,%r9,__LC_RETURN_PSW
	br	%r14
cleanup_sysc_restore_insn:
	.quad	sysc_done - 4

cleanup_io_tif:
	larl	%r9,io_tif
	br	%r14

cleanup_io_restore:
	clg	%r9,BASED(cleanup_io_restore_insn)
	je	0f
	lg	%r9,24(%r11)		# get saved r11 pointer to pt_regs
	mvc	__LC_RETURN_PSW(16),__PT_PSW(%r9)
	mvc	0(64,%r11),__PT_R8(%r9)
	lmg	%r0,%r7,__PT_R0(%r9)
0:	lmg	%r8,%r9,__LC_RETURN_PSW
	br	%r14
cleanup_io_restore_insn:
	.quad	io_done - 4

cleanup_idle:
	# copy interrupt clock & cpu timer
	mvc	__CLOCK_IDLE_EXIT(8,%r2),__LC_INT_CLOCK
	mvc	__TIMER_IDLE_EXIT(8,%r2),__LC_ASYNC_ENTER_TIMER
	cghi	%r11,__LC_SAVE_AREA_ASYNC
	je	0f
	mvc	__CLOCK_IDLE_EXIT(8,%r2),__LC_MCCK_CLOCK
	mvc	__TIMER_IDLE_EXIT(8,%r2),__LC_MCCK_ENTER_TIMER
0:	# check if stck & stpt have been executed
	clg	%r9,BASED(cleanup_idle_insn)
	jhe	1f
	mvc	__CLOCK_IDLE_ENTER(8,%r2),__CLOCK_IDLE_EXIT(%r2)
	mvc	__TIMER_IDLE_ENTER(8,%r2),__TIMER_IDLE_EXIT(%r2)
1:	# account system time going idle
	lg	%r9,__LC_STEAL_TIMER
	alg	%r9,__CLOCK_IDLE_ENTER(%r2)
	slg	%r9,__LC_LAST_UPDATE_CLOCK
	stg	%r9,__LC_STEAL_TIMER
	mvc	__LC_LAST_UPDATE_CLOCK(8),__CLOCK_IDLE_EXIT(%r2)
	lg	%r9,__LC_SYSTEM_TIMER
	alg	%r9,__LC_LAST_UPDATE_TIMER
	slg	%r9,__TIMER_IDLE_ENTER(%r2)
	stg	%r9,__LC_SYSTEM_TIMER
	mvc	__LC_LAST_UPDATE_TIMER(8),__TIMER_IDLE_EXIT(%r2)
	# prepare return psw
	nihh	%r8,0xfcfd		# clear irq & wait state bits
	lg	%r9,48(%r11)		# return from psw_idle
	br	%r14
cleanup_idle_insn:
	.quad	psw_idle_lpsw

/*
 * Integer constants
 */
	.align	8
.Lcritical_start:
	.quad	__critical_start
.Lcritical_length:
	.quad	__critical_end - __critical_start


#if defined(CONFIG_KVM) || defined(CONFIG_KVM_MODULE)
/*
 * sie64a calling convention:
 * %r2 pointer to sie control block
 * %r3 guest register save area
 */
ENTRY(sie64a)
	stmg	%r6,%r14,__SF_GPRS(%r15)	# save kernel registers
	stg	%r2,__SF_EMPTY(%r15)		# save control block pointer
	stg	%r3,__SF_EMPTY+8(%r15)		# save guest register save area
	xc	__SF_EMPTY+16(16,%r15),__SF_EMPTY+16(%r15) # host id & reason
	lmg	%r0,%r13,0(%r3)			# load guest gprs 0-13
	lg	%r14,__LC_GMAP			# get gmap pointer
	ltgr	%r14,%r14
	jz	sie_gmap
	lctlg	%c1,%c1,__GMAP_ASCE(%r14)	# load primary asce
sie_gmap:
	lg	%r14,__SF_EMPTY(%r15)		# get control block pointer
	oi	__SIE_PROG0C+3(%r14),1		# we are going into SIE now
	tm	__SIE_PROG20+3(%r14),1		# last exit...
	jnz	sie_done
	LPP	__SF_EMPTY(%r15)		# set guest id
	sie	0(%r14)
sie_done:
	LPP	__SF_EMPTY+16(%r15)		# set host id
	ni	__SIE_PROG0C+3(%r14),0xfe	# no longer in SIE
	lctlg	%c1,%c1,__LC_USER_ASCE		# load primary asce
# some program checks are suppressing. C code (e.g. do_protection_exception)
# will rewind the PSW by the ILC, which is 4 bytes in case of SIE. Other
# instructions beween sie64a and sie_done should not cause program
# interrupts. So lets use a nop (47 00 00 00) as a landing pad.
# See also HANDLE_SIE_INTERCEPT
rewind_pad:
	nop	0
	.globl sie_exit
sie_exit:
	lg	%r14,__SF_EMPTY+8(%r15)		# load guest register save area
	stmg	%r0,%r13,0(%r14)		# save guest gprs 0-13
	lmg	%r6,%r14,__SF_GPRS(%r15)	# restore kernel registers
	lg	%r2,__SF_EMPTY+24(%r15)		# return exit reason code
	br	%r14
sie_fault:
	lghi	%r14,-EFAULT
	stg	%r14,__SF_EMPTY+24(%r15)	# set exit reason code
	j	sie_exit

	.align	8
.Lsie_critical:
	.quad	sie_gmap
.Lsie_critical_length:
	.quad	sie_done - sie_gmap

	EX_TABLE(rewind_pad,sie_fault)
	EX_TABLE(sie_exit,sie_fault)
#endif

		.section .rodata, "a"
#define SYSCALL(esa,esame,emu)	.long esame
	.globl	sys_call_table
sys_call_table:
#include "syscalls.S"
#undef SYSCALL

#ifdef CONFIG_COMPAT

#define SYSCALL(esa,esame,emu)	.long emu
	.globl	sys_call_table_emu
sys_call_table_emu:
#include "syscalls.S"
#undef SYSCALL
#endif
OpenPOWER on IntegriCloud