xref: /linux/arch/s390/kernel/entry.S (revision f8324e20f8289dffc646d64366332e05eaacab25)
1/*
2 *  arch/s390/kernel/entry.S
3 *    S390 low-level entry points.
4 *
5 *    Copyright (C) IBM Corp. 1999,2006
6 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
7 *		 Hartmut Penner (hp@de.ibm.com),
8 *		 Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
9 *		 Heiko Carstens <heiko.carstens@de.ibm.com>
10 */
11
12#include <linux/sys.h>
13#include <linux/linkage.h>
14#include <linux/init.h>
15#include <asm/cache.h>
16#include <asm/errno.h>
17#include <asm/ptrace.h>
18#include <asm/thread_info.h>
19#include <asm/asm-offsets.h>
20#include <asm/unistd.h>
21#include <asm/page.h>
22
23/*
24 * Stack layout for the system_call stack entry.
25 * The first few entries are identical to the user_regs_struct.
26 */
27SP_PTREGS    =	STACK_FRAME_OVERHEAD
28SP_ARGS      =	STACK_FRAME_OVERHEAD + __PT_ARGS
29SP_PSW	     =	STACK_FRAME_OVERHEAD + __PT_PSW
30SP_R0	     =	STACK_FRAME_OVERHEAD + __PT_GPRS
31SP_R1	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 4
32SP_R2	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 8
33SP_R3	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 12
34SP_R4	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 16
35SP_R5	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 20
36SP_R6	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 24
37SP_R7	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 28
38SP_R8	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 32
39SP_R9	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 36
40SP_R10	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 40
41SP_R11	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 44
42SP_R12	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 48
43SP_R13	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 52
44SP_R14	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 56
45SP_R15	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 60
46SP_ORIG_R2   =	STACK_FRAME_OVERHEAD + __PT_ORIG_GPR2
47SP_ILC	     =	STACK_FRAME_OVERHEAD + __PT_ILC
48SP_SVCNR     =	STACK_FRAME_OVERHEAD + __PT_SVCNR
49SP_SIZE      =	STACK_FRAME_OVERHEAD + __PT_SIZE
50
51_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
52		 _TIF_MCCK_PENDING | _TIF_RESTART_SVC | _TIF_SINGLE_STEP )
53_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
54		 _TIF_MCCK_PENDING)
55_TIF_SYSCALL = (_TIF_SYSCALL_TRACE>>8 | _TIF_SYSCALL_AUDIT>>8 | \
56		_TIF_SECCOMP>>8 | _TIF_SYSCALL_TRACEPOINT>>8)
57
58STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
59STACK_SIZE  = 1 << STACK_SHIFT
60
61#define BASED(name) name-system_call(%r13)
62
63#ifdef CONFIG_TRACE_IRQFLAGS
64	.macro	TRACE_IRQS_ON
65	basr	%r2,%r0
66	l	%r1,BASED(.Ltrace_irq_on_caller)
67	basr	%r14,%r1
68	.endm
69
70	.macro	TRACE_IRQS_OFF
71	basr	%r2,%r0
72	l	%r1,BASED(.Ltrace_irq_off_caller)
73	basr	%r14,%r1
74	.endm
75
76	.macro	TRACE_IRQS_CHECK_ON
77	tm	SP_PSW(%r15),0x03	# irqs enabled?
78	bz	BASED(0f)
79	TRACE_IRQS_ON
800:
81	.endm
82
83	.macro	TRACE_IRQS_CHECK_OFF
84	tm	SP_PSW(%r15),0x03	# irqs enabled?
85	bz	BASED(0f)
86	TRACE_IRQS_OFF
870:
88	.endm
89#else
90#define TRACE_IRQS_ON
91#define TRACE_IRQS_OFF
92#define TRACE_IRQS_CHECK_ON
93#define TRACE_IRQS_CHECK_OFF
94#endif
95
96#ifdef CONFIG_LOCKDEP
97	.macro	LOCKDEP_SYS_EXIT
98	tm	SP_PSW+1(%r15),0x01	# returning to user ?
99	jz	0f
100	l	%r1,BASED(.Llockdep_sys_exit)
101	basr	%r14,%r1
1020:
103	.endm
104#else
105#define LOCKDEP_SYS_EXIT
106#endif
107
108/*
109 * Register usage in interrupt handlers:
110 *    R9  - pointer to current task structure
111 *    R13 - pointer to literal pool
112 *    R14 - return register for function calls
113 *    R15 - kernel stack pointer
114 */
115
116	.macro	UPDATE_VTIME lc_from,lc_to,lc_sum
117	lm	%r10,%r11,\lc_from
118	sl	%r10,\lc_to
119	sl	%r11,\lc_to+4
120	bc	3,BASED(0f)
121	sl	%r10,BASED(.Lc_1)
1220:	al	%r10,\lc_sum
123	al	%r11,\lc_sum+4
124	bc	12,BASED(1f)
125	al	%r10,BASED(.Lc_1)
1261:	stm	%r10,%r11,\lc_sum
127	.endm
128
129	.macro	SAVE_ALL_BASE savearea
130	stm	%r12,%r15,\savearea
131	l	%r13,__LC_SVC_NEW_PSW+4	# load &system_call to %r13
132	.endm
133
134	.macro	SAVE_ALL_SVC psworg,savearea
135	la	%r12,\psworg
136	l	%r15,__LC_KERNEL_STACK	# problem state -> load ksp
137	.endm
138
139	.macro	SAVE_ALL_SYNC psworg,savearea
140	la	%r12,\psworg
141	tm	\psworg+1,0x01		# test problem state bit
142	bz	BASED(2f)		# skip stack setup save
143	l	%r15,__LC_KERNEL_STACK	# problem state -> load ksp
144#ifdef CONFIG_CHECK_STACK
145	b	BASED(3f)
1462:	tml	%r15,STACK_SIZE - CONFIG_STACK_GUARD
147	bz	BASED(stack_overflow)
1483:
149#endif
1502:
151	.endm
152
153	.macro	SAVE_ALL_ASYNC psworg,savearea
154	la	%r12,\psworg
155	tm	\psworg+1,0x01		# test problem state bit
156	bnz	BASED(1f)		# from user -> load async stack
157	clc	\psworg+4(4),BASED(.Lcritical_end)
158	bhe	BASED(0f)
159	clc	\psworg+4(4),BASED(.Lcritical_start)
160	bl	BASED(0f)
161	l	%r14,BASED(.Lcleanup_critical)
162	basr	%r14,%r14
163	tm	1(%r12),0x01		# retest problem state after cleanup
164	bnz	BASED(1f)
1650:	l	%r14,__LC_ASYNC_STACK	# are we already on the async stack ?
166	slr	%r14,%r15
167	sra	%r14,STACK_SHIFT
168	be	BASED(2f)
1691:	l	%r15,__LC_ASYNC_STACK
170#ifdef CONFIG_CHECK_STACK
171	b	BASED(3f)
1722:	tml	%r15,STACK_SIZE - CONFIG_STACK_GUARD
173	bz	BASED(stack_overflow)
1743:
175#endif
1762:
177	.endm
178
179	.macro	CREATE_STACK_FRAME psworg,savearea
180	s	%r15,BASED(.Lc_spsize)	# make room for registers & psw
181	mvc	SP_PSW(8,%r15),0(%r12)	# move user PSW to stack
182	st	%r2,SP_ORIG_R2(%r15)	# store original content of gpr 2
183	icm	%r12,12,__LC_SVC_ILC
184	stm	%r0,%r11,SP_R0(%r15)	# store gprs %r0-%r11 to kernel stack
185	st	%r12,SP_ILC(%r15)
186	mvc	SP_R12(16,%r15),\savearea # move %r12-%r15 to stack
187	la	%r12,0
188	st	%r12,__SF_BACKCHAIN(%r15)	# clear back chain
189	.endm
190
191	.macro	RESTORE_ALL psworg,sync
192	mvc	\psworg(8),SP_PSW(%r15) # move user PSW to lowcore
193	.if !\sync
194	ni	\psworg+1,0xfd		# clear wait state bit
195	.endif
196	lm	%r0,%r15,SP_R0(%r15)	# load gprs 0-15 of user
197	stpt	__LC_EXIT_TIMER
198	lpsw	\psworg			# back to caller
199	.endm
200
201/*
202 * Scheduler resume function, called by switch_to
203 *  gpr2 = (task_struct *) prev
204 *  gpr3 = (task_struct *) next
205 * Returns:
206 *  gpr2 = prev
207 */
208	.globl	__switch_to
209__switch_to:
210	basr	%r1,0
211__switch_to_base:
212	tm	__THREAD_per(%r3),0xe8		# new process is using per ?
213	bz	__switch_to_noper-__switch_to_base(%r1)	# if not we're fine
214	stctl	%c9,%c11,__SF_EMPTY(%r15)	# We are using per stuff
215	clc	__THREAD_per(12,%r3),__SF_EMPTY(%r15)
216	be	__switch_to_noper-__switch_to_base(%r1)	# we got away w/o bashing TLB's
217	lctl	%c9,%c11,__THREAD_per(%r3)	# Nope we didn't
218__switch_to_noper:
219	l	%r4,__THREAD_info(%r2)		# get thread_info of prev
220	tm	__TI_flags+3(%r4),_TIF_MCCK_PENDING # machine check pending?
221	bz	__switch_to_no_mcck-__switch_to_base(%r1)
222	ni	__TI_flags+3(%r4),255-_TIF_MCCK_PENDING # clear flag in prev
223	l	%r4,__THREAD_info(%r3)		# get thread_info of next
224	oi	__TI_flags+3(%r4),_TIF_MCCK_PENDING # set it in next
225__switch_to_no_mcck:
226	stm	%r6,%r15,__SF_GPRS(%r15)# store __switch_to registers of prev task
227	st	%r15,__THREAD_ksp(%r2)	# store kernel stack to prev->tss.ksp
228	l	%r15,__THREAD_ksp(%r3)	# load kernel stack from next->tss.ksp
229	lm	%r6,%r15,__SF_GPRS(%r15)# load __switch_to registers of next task
230	st	%r3,__LC_CURRENT	# __LC_CURRENT = current task struct
231	lctl	%c4,%c4,__TASK_pid(%r3) # load pid to control reg. 4
232	l	%r3,__THREAD_info(%r3)	# load thread_info from task struct
233	st	%r3,__LC_THREAD_INFO
234	ahi	%r3,STACK_SIZE
235	st	%r3,__LC_KERNEL_STACK	# __LC_KERNEL_STACK = new kernel stack
236	br	%r14
237
238__critical_start:
239/*
240 * SVC interrupt handler routine. System calls are synchronous events and
241 * are executed with interrupts enabled.
242 */
243
244	.globl	system_call
245system_call:
246	stpt	__LC_SYNC_ENTER_TIMER
247sysc_saveall:
248	SAVE_ALL_BASE __LC_SAVE_AREA
249	SAVE_ALL_SVC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
250	CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
251	lh	%r7,0x8a	  # get svc number from lowcore
252sysc_vtime:
253	UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
254sysc_stime:
255	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
256sysc_update:
257	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
258sysc_do_svc:
259	l	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
260	ltr	%r7,%r7			# test for svc 0
261	bnz	BASED(sysc_nr_ok)	# svc number > 0
262	# svc 0: system call number in %r1
263	cl	%r1,BASED(.Lnr_syscalls)
264	bnl	BASED(sysc_nr_ok)
265	lr	%r7,%r1 	  # copy svc number to %r7
266sysc_nr_ok:
267	mvc	SP_ARGS(4,%r15),SP_R7(%r15)
268sysc_do_restart:
269	sth	%r7,SP_SVCNR(%r15)
270	sll	%r7,2		  # svc number *4
271	l	%r8,BASED(.Lsysc_table)
272	tm	__TI_flags+2(%r9),_TIF_SYSCALL
273	l	%r8,0(%r7,%r8)	  # get system call addr.
274	bnz	BASED(sysc_tracesys)
275	basr	%r14,%r8	  # call sys_xxxx
276	st	%r2,SP_R2(%r15)   # store return value (change R2 on stack)
277
278sysc_return:
279	LOCKDEP_SYS_EXIT
280sysc_tif:
281	tm	__TI_flags+3(%r9),_TIF_WORK_SVC
282	bnz	BASED(sysc_work)  # there is work to do (signals etc.)
283sysc_restore:
284	RESTORE_ALL __LC_RETURN_PSW,1
285sysc_done:
286
287#
288# There is work to do, but first we need to check if we return to userspace.
289#
290sysc_work:
291	tm	SP_PSW+1(%r15),0x01	# returning to user ?
292	bno	BASED(sysc_restore)
293
294#
295# One of the work bits is on. Find out which one.
296#
297sysc_work_tif:
298	tm	__TI_flags+3(%r9),_TIF_MCCK_PENDING
299	bo	BASED(sysc_mcck_pending)
300	tm	__TI_flags+3(%r9),_TIF_NEED_RESCHED
301	bo	BASED(sysc_reschedule)
302	tm	__TI_flags+3(%r9),_TIF_SIGPENDING
303	bo	BASED(sysc_sigpending)
304	tm	__TI_flags+3(%r9),_TIF_NOTIFY_RESUME
305	bo	BASED(sysc_notify_resume)
306	tm	__TI_flags+3(%r9),_TIF_RESTART_SVC
307	bo	BASED(sysc_restart)
308	tm	__TI_flags+3(%r9),_TIF_SINGLE_STEP
309	bo	BASED(sysc_singlestep)
310	b	BASED(sysc_return)	# beware of critical section cleanup
311
312#
313# _TIF_NEED_RESCHED is set, call schedule
314#
315sysc_reschedule:
316	l	%r1,BASED(.Lschedule)
317	la	%r14,BASED(sysc_return)
318	br	%r1			# call scheduler
319
320#
321# _TIF_MCCK_PENDING is set, call handler
322#
323sysc_mcck_pending:
324	l	%r1,BASED(.Ls390_handle_mcck)
325	la	%r14,BASED(sysc_return)
326	br	%r1			# TIF bit will be cleared by handler
327
328#
329# _TIF_SIGPENDING is set, call do_signal
330#
331sysc_sigpending:
332	ni	__TI_flags+3(%r9),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
333	la	%r2,SP_PTREGS(%r15)	# load pt_regs
334	l	%r1,BASED(.Ldo_signal)
335	basr	%r14,%r1		# call do_signal
336	tm	__TI_flags+3(%r9),_TIF_RESTART_SVC
337	bo	BASED(sysc_restart)
338	tm	__TI_flags+3(%r9),_TIF_SINGLE_STEP
339	bo	BASED(sysc_singlestep)
340	b	BASED(sysc_return)
341
342#
343# _TIF_NOTIFY_RESUME is set, call do_notify_resume
344#
345sysc_notify_resume:
346	la	%r2,SP_PTREGS(%r15)	# load pt_regs
347	l	%r1,BASED(.Ldo_notify_resume)
348	la	%r14,BASED(sysc_return)
349	br	%r1			# call do_notify_resume
350
351
352#
353# _TIF_RESTART_SVC is set, set up registers and restart svc
354#
355sysc_restart:
356	ni	__TI_flags+3(%r9),255-_TIF_RESTART_SVC # clear TIF_RESTART_SVC
357	l	%r7,SP_R2(%r15) 	# load new svc number
358	mvc	SP_R2(4,%r15),SP_ORIG_R2(%r15) # restore first argument
359	lm	%r2,%r6,SP_R2(%r15)	# load svc arguments
360	b	BASED(sysc_do_restart)	# restart svc
361
362#
363# _TIF_SINGLE_STEP is set, call do_single_step
364#
365sysc_singlestep:
366	ni	__TI_flags+3(%r9),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
367	mvi	SP_SVCNR(%r15),0xff	# set trap indication to pgm check
368	mvi	SP_SVCNR+1(%r15),0xff
369	la	%r2,SP_PTREGS(%r15)	# address of register-save area
370	l	%r1,BASED(.Lhandle_per)	# load adr. of per handler
371	la	%r14,BASED(sysc_return)	# load adr. of system return
372	br	%r1			# branch to do_single_step
373
374#
375# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
376# and after the system call
377#
378sysc_tracesys:
379	l	%r1,BASED(.Ltrace_entry)
380	la	%r2,SP_PTREGS(%r15)	# load pt_regs
381	la	%r3,0
382	srl	%r7,2
383	st	%r7,SP_R2(%r15)
384	basr	%r14,%r1
385	cl	%r2,BASED(.Lnr_syscalls)
386	bnl	BASED(sysc_tracenogo)
387	l	%r8,BASED(.Lsysc_table)
388	lr	%r7,%r2
389	sll	%r7,2			# svc number *4
390	l	%r8,0(%r7,%r8)
391sysc_tracego:
392	lm	%r3,%r6,SP_R3(%r15)
393	l	%r2,SP_ORIG_R2(%r15)
394	basr	%r14,%r8		# call sys_xxx
395	st	%r2,SP_R2(%r15)		# store return value
396sysc_tracenogo:
397	tm	__TI_flags+2(%r9),_TIF_SYSCALL
398	bz	BASED(sysc_return)
399	l	%r1,BASED(.Ltrace_exit)
400	la	%r2,SP_PTREGS(%r15)	# load pt_regs
401	la	%r14,BASED(sysc_return)
402	br	%r1
403
404#
405# a new process exits the kernel with ret_from_fork
406#
407	.globl	ret_from_fork
408ret_from_fork:
409	l	%r13,__LC_SVC_NEW_PSW+4
410	l	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
411	tm	SP_PSW+1(%r15),0x01	# forking a kernel thread ?
412	bo	BASED(0f)
413	st	%r15,SP_R15(%r15)	# store stack pointer for new kthread
4140:	l	%r1,BASED(.Lschedtail)
415	basr	%r14,%r1
416	TRACE_IRQS_ON
417	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
418	b	BASED(sysc_tracenogo)
419
420#
421# kernel_execve function needs to deal with pt_regs that is not
422# at the usual place
423#
424	.globl	kernel_execve
425kernel_execve:
426	stm	%r12,%r15,48(%r15)
427	lr	%r14,%r15
428	l	%r13,__LC_SVC_NEW_PSW+4
429	s	%r15,BASED(.Lc_spsize)
430	st	%r14,__SF_BACKCHAIN(%r15)
431	la	%r12,SP_PTREGS(%r15)
432	xc	0(__PT_SIZE,%r12),0(%r12)
433	l	%r1,BASED(.Ldo_execve)
434	lr	%r5,%r12
435	basr	%r14,%r1
436	ltr	%r2,%r2
437	be	BASED(0f)
438	a	%r15,BASED(.Lc_spsize)
439	lm	%r12,%r15,48(%r15)
440	br	%r14
441	# execve succeeded.
4420:	stnsm	__SF_EMPTY(%r15),0xfc	# disable interrupts
443	TRACE_IRQS_OFF
444	l	%r15,__LC_KERNEL_STACK	# load ksp
445	s	%r15,BASED(.Lc_spsize)	# make room for registers & psw
446	l	%r9,__LC_THREAD_INFO
447	mvc	SP_PTREGS(__PT_SIZE,%r15),0(%r12)	# copy pt_regs
448	xc	__SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
449	TRACE_IRQS_ON
450	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
451	l	%r1,BASED(.Lexecve_tail)
452	basr	%r14,%r1
453	b	BASED(sysc_return)
454
455/*
456 * Program check handler routine
457 */
458
459	.globl	pgm_check_handler
460pgm_check_handler:
461/*
462 * First we need to check for a special case:
463 * Single stepping an instruction that disables the PER event mask will
464 * cause a PER event AFTER the mask has been set. Example: SVC or LPSW.
465 * For a single stepped SVC the program check handler gets control after
466 * the SVC new PSW has been loaded. But we want to execute the SVC first and
467 * then handle the PER event. Therefore we update the SVC old PSW to point
468 * to the pgm_check_handler and branch to the SVC handler after we checked
469 * if we have to load the kernel stack register.
470 * For every other possible cause for PER event without the PER mask set
471 * we just ignore the PER event (FIXME: is there anything we have to do
472 * for LPSW?).
473 */
474	stpt	__LC_SYNC_ENTER_TIMER
475	SAVE_ALL_BASE __LC_SAVE_AREA
476	tm	__LC_PGM_INT_CODE+1,0x80 # check whether we got a per exception
477	bnz	BASED(pgm_per)		# got per exception -> special case
478	SAVE_ALL_SYNC __LC_PGM_OLD_PSW,__LC_SAVE_AREA
479	CREATE_STACK_FRAME __LC_PGM_OLD_PSW,__LC_SAVE_AREA
480	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
481	bz	BASED(pgm_no_vtime)
482	UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
483	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
484	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
485pgm_no_vtime:
486	TRACE_IRQS_CHECK_OFF
487	l	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
488	l	%r3,__LC_PGM_ILC	# load program interruption code
489	la	%r8,0x7f
490	nr	%r8,%r3
491pgm_do_call:
492	l	%r7,BASED(.Ljump_table)
493	sll	%r8,2
494	l	%r7,0(%r8,%r7)		# load address of handler routine
495	la	%r2,SP_PTREGS(%r15)	# address of register-save area
496	basr	%r14,%r7		# branch to interrupt-handler
497pgm_exit:
498	TRACE_IRQS_CHECK_ON
499	b	BASED(sysc_return)
500
501#
502# handle per exception
503#
504pgm_per:
505	tm	__LC_PGM_OLD_PSW,0x40	# test if per event recording is on
506	bnz	BASED(pgm_per_std)	# ok, normal per event from user space
507# ok its one of the special cases, now we need to find out which one
508	clc	__LC_PGM_OLD_PSW(8),__LC_SVC_NEW_PSW
509	be	BASED(pgm_svcper)
510# no interesting special case, ignore PER event
511	lm	%r12,%r15,__LC_SAVE_AREA
512	lpsw	0x28
513
514#
515# Normal per exception
516#
517pgm_per_std:
518	SAVE_ALL_SYNC __LC_PGM_OLD_PSW,__LC_SAVE_AREA
519	CREATE_STACK_FRAME __LC_PGM_OLD_PSW,__LC_SAVE_AREA
520	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
521	bz	BASED(pgm_no_vtime2)
522	UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
523	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
524	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
525pgm_no_vtime2:
526	TRACE_IRQS_CHECK_OFF
527	l	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
528	l	%r1,__TI_task(%r9)
529	tm	SP_PSW+1(%r15),0x01	# kernel per event ?
530	bz	BASED(kernel_per)
531	mvc	__THREAD_per+__PER_atmid(2,%r1),__LC_PER_ATMID
532	mvc	__THREAD_per+__PER_address(4,%r1),__LC_PER_ADDRESS
533	mvc	__THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID
534	oi	__TI_flags+3(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
535	l	%r3,__LC_PGM_ILC	# load program interruption code
536	la	%r8,0x7f
537	nr	%r8,%r3 		# clear per-event-bit and ilc
538	be	BASED(pgm_exit)		# only per or per+check ?
539	b	BASED(pgm_do_call)
540
541#
542# it was a single stepped SVC that is causing all the trouble
543#
544pgm_svcper:
545	SAVE_ALL_SYNC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
546	CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
547	UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
548	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
549	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
550	lh	%r7,0x8a		# get svc number from lowcore
551	l	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
552	TRACE_IRQS_OFF
553	l	%r8,__TI_task(%r9)
554	mvc	__THREAD_per+__PER_atmid(2,%r8),__LC_PER_ATMID
555	mvc	__THREAD_per+__PER_address(4,%r8),__LC_PER_ADDRESS
556	mvc	__THREAD_per+__PER_access_id(1,%r8),__LC_PER_ACCESS_ID
557	oi	__TI_flags+3(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
558	TRACE_IRQS_ON
559	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
560	lm	%r2,%r6,SP_R2(%r15)	# load svc arguments
561	b	BASED(sysc_do_svc)
562
563#
564# per was called from kernel, must be kprobes
565#
566kernel_per:
567	mvi	SP_SVCNR(%r15),0xff	# set trap indication to pgm check
568	mvi	SP_SVCNR+1(%r15),0xff
569	la	%r2,SP_PTREGS(%r15)	# address of register-save area
570	l	%r1,BASED(.Lhandle_per)	# load adr. of per handler
571	basr	%r14,%r1		# branch to do_single_step
572	b	BASED(pgm_exit)
573
574/*
575 * IO interrupt handler routine
576 */
577
578	.globl io_int_handler
579io_int_handler:
580	stck	__LC_INT_CLOCK
581	stpt	__LC_ASYNC_ENTER_TIMER
582	SAVE_ALL_BASE __LC_SAVE_AREA+16
583	SAVE_ALL_ASYNC __LC_IO_OLD_PSW,__LC_SAVE_AREA+16
584	CREATE_STACK_FRAME __LC_IO_OLD_PSW,__LC_SAVE_AREA+16
585	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
586	bz	BASED(io_no_vtime)
587	UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
588	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
589	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
590io_no_vtime:
591	TRACE_IRQS_OFF
592	l	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
593	l	%r1,BASED(.Ldo_IRQ)	# load address of do_IRQ
594	la	%r2,SP_PTREGS(%r15)	# address of register-save area
595	basr	%r14,%r1		# branch to standard irq handler
596io_return:
597	LOCKDEP_SYS_EXIT
598	TRACE_IRQS_ON
599io_tif:
600	tm	__TI_flags+3(%r9),_TIF_WORK_INT
601	bnz	BASED(io_work)		# there is work to do (signals etc.)
602io_restore:
603	RESTORE_ALL __LC_RETURN_PSW,0
604io_done:
605
606#
607# There is work todo, find out in which context we have been interrupted:
608# 1) if we return to user space we can do all _TIF_WORK_INT work
609# 2) if we return to kernel code and preemptive scheduling is enabled check
610#    the preemption counter and if it is zero call preempt_schedule_irq
611# Before any work can be done, a switch to the kernel stack is required.
612#
613io_work:
614	tm	SP_PSW+1(%r15),0x01	# returning to user ?
615	bo	BASED(io_work_user)	# yes -> do resched & signal
616#ifdef CONFIG_PREEMPT
617	# check for preemptive scheduling
618	icm	%r0,15,__TI_precount(%r9)
619	bnz	BASED(io_restore)	# preemption disabled
620	tm	__TI_flags+3(%r9),_TIF_NEED_RESCHED
621	bno	BASED(io_restore)
622	# switch to kernel stack
623	l	%r1,SP_R15(%r15)
624	s	%r1,BASED(.Lc_spsize)
625	mvc	SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
626	xc	__SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain
627	lr	%r15,%r1
628	# TRACE_IRQS_ON already done at io_return, call
629	# TRACE_IRQS_OFF to keep things symmetrical
630	TRACE_IRQS_OFF
631	l	%r1,BASED(.Lpreempt_schedule_irq)
632	basr	%r14,%r1		# call preempt_schedule_irq
633	b	BASED(io_return)
634#else
635	b	BASED(io_restore)
636#endif
637
638#
639# Need to do work before returning to userspace, switch to kernel stack
640#
641io_work_user:
642	l	%r1,__LC_KERNEL_STACK
643	s	%r1,BASED(.Lc_spsize)
644	mvc	SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
645	xc	__SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain
646	lr	%r15,%r1
647
648#
649# One of the work bits is on. Find out which one.
650# Checked are: _TIF_SIGPENDING, _TIF_NOTIFY_RESUME, _TIF_NEED_RESCHED
651#		and _TIF_MCCK_PENDING
652#
653io_work_tif:
654	tm	__TI_flags+3(%r9),_TIF_MCCK_PENDING
655	bo	BASED(io_mcck_pending)
656	tm	__TI_flags+3(%r9),_TIF_NEED_RESCHED
657	bo	BASED(io_reschedule)
658	tm	__TI_flags+3(%r9),_TIF_SIGPENDING
659	bo	BASED(io_sigpending)
660	tm	__TI_flags+3(%r9),_TIF_NOTIFY_RESUME
661	bo	BASED(io_notify_resume)
662	b	BASED(io_return)	# beware of critical section cleanup
663
664#
665# _TIF_MCCK_PENDING is set, call handler
666#
667io_mcck_pending:
668	# TRACE_IRQS_ON already done at io_return
669	l	%r1,BASED(.Ls390_handle_mcck)
670	basr	%r14,%r1		# TIF bit will be cleared by handler
671	TRACE_IRQS_OFF
672	b	BASED(io_return)
673
674#
675# _TIF_NEED_RESCHED is set, call schedule
676#
677io_reschedule:
678	# TRACE_IRQS_ON already done at io_return
679	l	%r1,BASED(.Lschedule)
680	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
681	basr	%r14,%r1		# call scheduler
682	stnsm	__SF_EMPTY(%r15),0xfc	# disable I/O and ext. interrupts
683	TRACE_IRQS_OFF
684	b	BASED(io_return)
685
686#
687# _TIF_SIGPENDING is set, call do_signal
688#
689io_sigpending:
690	# TRACE_IRQS_ON already done at io_return
691	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
692	la	%r2,SP_PTREGS(%r15)	# load pt_regs
693	l	%r1,BASED(.Ldo_signal)
694	basr	%r14,%r1		# call do_signal
695	stnsm	__SF_EMPTY(%r15),0xfc	# disable I/O and ext. interrupts
696	TRACE_IRQS_OFF
697	b	BASED(io_return)
698
699#
700# _TIF_SIGPENDING is set, call do_signal
701#
702io_notify_resume:
703	# TRACE_IRQS_ON already done at io_return
704	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
705	la	%r2,SP_PTREGS(%r15)	# load pt_regs
706	l	%r1,BASED(.Ldo_notify_resume)
707	basr	%r14,%r1		# call do_signal
708	stnsm	__SF_EMPTY(%r15),0xfc	# disable I/O and ext. interrupts
709	TRACE_IRQS_OFF
710	b	BASED(io_return)
711
712/*
713 * External interrupt handler routine
714 */
715
716	.globl	ext_int_handler
717ext_int_handler:
718	stck	__LC_INT_CLOCK
719	stpt	__LC_ASYNC_ENTER_TIMER
720	SAVE_ALL_BASE __LC_SAVE_AREA+16
721	SAVE_ALL_ASYNC __LC_EXT_OLD_PSW,__LC_SAVE_AREA+16
722	CREATE_STACK_FRAME __LC_EXT_OLD_PSW,__LC_SAVE_AREA+16
723	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
724	bz	BASED(ext_no_vtime)
725	UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
726	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
727	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
728ext_no_vtime:
729	l	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
730	TRACE_IRQS_OFF
731	la	%r2,SP_PTREGS(%r15)	# address of register-save area
732	lh	%r3,__LC_EXT_INT_CODE	# get interruption code
733	l	%r1,BASED(.Ldo_extint)
734	basr	%r14,%r1
735	b	BASED(io_return)
736
737__critical_end:
738
739/*
740 * Machine check handler routines
741 */
742
743	.globl mcck_int_handler
744mcck_int_handler:
745	stck	__LC_MCCK_CLOCK
746	spt	__LC_CPU_TIMER_SAVE_AREA	# revalidate cpu timer
747	lm	%r0,%r15,__LC_GPREGS_SAVE_AREA	# revalidate gprs
748	SAVE_ALL_BASE __LC_SAVE_AREA+32
749	la	%r12,__LC_MCK_OLD_PSW
750	tm	__LC_MCCK_CODE,0x80	# system damage?
751	bo	BASED(mcck_int_main)	# yes -> rest of mcck code invalid
752	mvc	__LC_MCCK_ENTER_TIMER(8),__LC_CPU_TIMER_SAVE_AREA
753	tm	__LC_MCCK_CODE+5,0x02	# stored cpu timer value valid?
754	bo	BASED(1f)
755	la	%r14,__LC_SYNC_ENTER_TIMER
756	clc	0(8,%r14),__LC_ASYNC_ENTER_TIMER
757	bl	BASED(0f)
758	la	%r14,__LC_ASYNC_ENTER_TIMER
7590:	clc	0(8,%r14),__LC_EXIT_TIMER
760	bl	BASED(0f)
761	la	%r14,__LC_EXIT_TIMER
7620:	clc	0(8,%r14),__LC_LAST_UPDATE_TIMER
763	bl	BASED(0f)
764	la	%r14,__LC_LAST_UPDATE_TIMER
7650:	spt	0(%r14)
766	mvc	__LC_MCCK_ENTER_TIMER(8),0(%r14)
7671:	tm	__LC_MCCK_CODE+2,0x09	# mwp + ia of old psw valid?
768	bno	BASED(mcck_int_main)	# no -> skip cleanup critical
769	tm	__LC_MCK_OLD_PSW+1,0x01	# test problem state bit
770	bnz	BASED(mcck_int_main)	# from user -> load async stack
771	clc	__LC_MCK_OLD_PSW+4(4),BASED(.Lcritical_end)
772	bhe	BASED(mcck_int_main)
773	clc	__LC_MCK_OLD_PSW+4(4),BASED(.Lcritical_start)
774	bl	BASED(mcck_int_main)
775	l	%r14,BASED(.Lcleanup_critical)
776	basr	%r14,%r14
777mcck_int_main:
778	l	%r14,__LC_PANIC_STACK	# are we already on the panic stack?
779	slr	%r14,%r15
780	sra	%r14,PAGE_SHIFT
781	be	BASED(0f)
782	l	%r15,__LC_PANIC_STACK	# load panic stack
7830:	CREATE_STACK_FRAME __LC_MCK_OLD_PSW,__LC_SAVE_AREA+32
784	tm	__LC_MCCK_CODE+2,0x08	# mwp of old psw valid?
785	bno	BASED(mcck_no_vtime)	# no -> skip cleanup critical
786	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
787	bz	BASED(mcck_no_vtime)
788	UPDATE_VTIME __LC_EXIT_TIMER,__LC_MCCK_ENTER_TIMER,__LC_USER_TIMER
789	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
790	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_MCCK_ENTER_TIMER
791mcck_no_vtime:
792	l	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
793	la	%r2,SP_PTREGS(%r15)	# load pt_regs
794	l	%r1,BASED(.Ls390_mcck)
795	basr	%r14,%r1		# call machine check handler
796	tm	SP_PSW+1(%r15),0x01	# returning to user ?
797	bno	BASED(mcck_return)
798	l	%r1,__LC_KERNEL_STACK	# switch to kernel stack
799	s	%r1,BASED(.Lc_spsize)
800	mvc	SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
801	xc	__SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain
802	lr	%r15,%r1
803	stosm	__SF_EMPTY(%r15),0x04	# turn dat on
804	tm	__TI_flags+3(%r9),_TIF_MCCK_PENDING
805	bno	BASED(mcck_return)
806	TRACE_IRQS_OFF
807	l	%r1,BASED(.Ls390_handle_mcck)
808	basr	%r14,%r1		# call machine check handler
809	TRACE_IRQS_ON
810mcck_return:
811	mvc	__LC_RETURN_MCCK_PSW(8),SP_PSW(%r15) # move return PSW
812	ni	__LC_RETURN_MCCK_PSW+1,0xfd # clear wait state bit
813	tm	__LC_RETURN_MCCK_PSW+1,0x01 # returning to user ?
814	bno	BASED(0f)
815	lm	%r0,%r15,SP_R0(%r15)	# load gprs 0-15
816	stpt	__LC_EXIT_TIMER
817	lpsw	__LC_RETURN_MCCK_PSW	# back to caller
8180:	lm	%r0,%r15,SP_R0(%r15)	# load gprs 0-15
819	lpsw	__LC_RETURN_MCCK_PSW	# back to caller
820
821	RESTORE_ALL __LC_RETURN_MCCK_PSW,0
822
823/*
824 * Restart interruption handler, kick starter for additional CPUs
825 */
826#ifdef CONFIG_SMP
827	__CPUINIT
828	.globl restart_int_handler
829restart_int_handler:
830	basr	%r1,0
831restart_base:
832	spt	restart_vtime-restart_base(%r1)
833	stck	__LC_LAST_UPDATE_CLOCK
834	mvc	__LC_LAST_UPDATE_TIMER(8),restart_vtime-restart_base(%r1)
835	mvc	__LC_EXIT_TIMER(8),restart_vtime-restart_base(%r1)
836	l	%r15,__LC_SAVE_AREA+60	# load ksp
837	lctl	%c0,%c15,__LC_CREGS_SAVE_AREA # get new ctl regs
838	lam	%a0,%a15,__LC_AREGS_SAVE_AREA
839	lm	%r6,%r15,__SF_GPRS(%r15) # load registers from clone
840	l	%r1,__LC_THREAD_INFO
841	mvc	__LC_USER_TIMER(8),__TI_user_timer(%r1)
842	mvc	__LC_SYSTEM_TIMER(8),__TI_system_timer(%r1)
843	xc	__LC_STEAL_TIMER(8),__LC_STEAL_TIMER
844	stosm	__SF_EMPTY(%r15),0x04	# now we can turn dat on
845	basr	%r14,0
846	l	%r14,restart_addr-.(%r14)
847	br	%r14			# branch to start_secondary
848restart_addr:
849	.long	start_secondary
850	.align	8
851restart_vtime:
852	.long	0x7fffffff,0xffffffff
853	.previous
854#else
855/*
856 * If we do not run with SMP enabled, let the new CPU crash ...
857 */
858	.globl restart_int_handler
859restart_int_handler:
860	basr	%r1,0
861restart_base:
862	lpsw	restart_crash-restart_base(%r1)
863	.align	8
864restart_crash:
865	.long	0x000a0000,0x00000000
866restart_go:
867#endif
868
869#ifdef CONFIG_CHECK_STACK
870/*
871 * The synchronous or the asynchronous stack overflowed. We are dead.
872 * No need to properly save the registers, we are going to panic anyway.
873 * Setup a pt_regs so that show_trace can provide a good call trace.
874 */
875stack_overflow:
876	l	%r15,__LC_PANIC_STACK	# change to panic stack
877	sl	%r15,BASED(.Lc_spsize)
878	mvc	SP_PSW(8,%r15),0(%r12)	# move user PSW to stack
879	stm	%r0,%r11,SP_R0(%r15)	# store gprs %r0-%r11 to kernel stack
880	la	%r1,__LC_SAVE_AREA
881	ch	%r12,BASED(.L0x020)	# old psw addr == __LC_SVC_OLD_PSW ?
882	be	BASED(0f)
883	ch	%r12,BASED(.L0x028)	# old psw addr == __LC_PGM_OLD_PSW ?
884	be	BASED(0f)
885	la	%r1,__LC_SAVE_AREA+16
8860:	mvc	SP_R12(16,%r15),0(%r1)	# move %r12-%r15 to stack
887	xc	__SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) # clear back chain
888	l	%r1,BASED(1f)		# branch to kernel_stack_overflow
889	la	%r2,SP_PTREGS(%r15)	# load pt_regs
890	br	%r1
8911:	.long	kernel_stack_overflow
892#endif
893
894cleanup_table_system_call:
895	.long	system_call + 0x80000000, sysc_do_svc + 0x80000000
896cleanup_table_sysc_tif:
897	.long	sysc_tif + 0x80000000, sysc_restore + 0x80000000
898cleanup_table_sysc_restore:
899	.long	sysc_restore + 0x80000000, sysc_done + 0x80000000
900cleanup_table_io_tif:
901	.long	io_tif + 0x80000000, io_restore + 0x80000000
902cleanup_table_io_restore:
903	.long	io_restore + 0x80000000, io_done + 0x80000000
904
905cleanup_critical:
906	clc	4(4,%r12),BASED(cleanup_table_system_call)
907	bl	BASED(0f)
908	clc	4(4,%r12),BASED(cleanup_table_system_call+4)
909	bl	BASED(cleanup_system_call)
9100:
911	clc	4(4,%r12),BASED(cleanup_table_sysc_tif)
912	bl	BASED(0f)
913	clc	4(4,%r12),BASED(cleanup_table_sysc_tif+4)
914	bl	BASED(cleanup_sysc_tif)
9150:
916	clc	4(4,%r12),BASED(cleanup_table_sysc_restore)
917	bl	BASED(0f)
918	clc	4(4,%r12),BASED(cleanup_table_sysc_restore+4)
919	bl	BASED(cleanup_sysc_restore)
9200:
921	clc	4(4,%r12),BASED(cleanup_table_io_tif)
922	bl	BASED(0f)
923	clc	4(4,%r12),BASED(cleanup_table_io_tif+4)
924	bl	BASED(cleanup_io_tif)
9250:
926	clc	4(4,%r12),BASED(cleanup_table_io_restore)
927	bl	BASED(0f)
928	clc	4(4,%r12),BASED(cleanup_table_io_restore+4)
929	bl	BASED(cleanup_io_restore)
9300:
931	br	%r14
932
933cleanup_system_call:
934	mvc	__LC_RETURN_PSW(8),0(%r12)
935	clc	__LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+4)
936	bh	BASED(0f)
937	mvc	__LC_SYNC_ENTER_TIMER(8),__LC_MCCK_ENTER_TIMER
938	c	%r12,BASED(.Lmck_old_psw)
939	be	BASED(0f)
940	mvc	__LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER
9410:	c	%r12,BASED(.Lmck_old_psw)
942	la	%r12,__LC_SAVE_AREA+32
943	be	BASED(0f)
944	la	%r12,__LC_SAVE_AREA+16
9450:	clc	__LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+8)
946	bhe	BASED(cleanup_vtime)
947	clc	__LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn)
948	bh	BASED(0f)
949	mvc	__LC_SAVE_AREA(16),0(%r12)
9500:	st	%r13,4(%r12)
951	st	%r12,__LC_SAVE_AREA+48	# argh
952	SAVE_ALL_SYNC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
953	CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
954	l	%r12,__LC_SAVE_AREA+48	# argh
955	st	%r15,12(%r12)
956	lh	%r7,0x8a
957cleanup_vtime:
958	clc	__LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+12)
959	bhe	BASED(cleanup_stime)
960	UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
961cleanup_stime:
962	clc	__LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+16)
963	bh	BASED(cleanup_update)
964	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
965cleanup_update:
966	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
967	mvc	__LC_RETURN_PSW+4(4),BASED(cleanup_table_system_call+4)
968	la	%r12,__LC_RETURN_PSW
969	br	%r14
970cleanup_system_call_insn:
971	.long	sysc_saveall + 0x80000000
972	.long	system_call + 0x80000000
973	.long	sysc_vtime + 0x80000000
974	.long	sysc_stime + 0x80000000
975	.long	sysc_update + 0x80000000
976
977cleanup_sysc_tif:
978	mvc	__LC_RETURN_PSW(4),0(%r12)
979	mvc	__LC_RETURN_PSW+4(4),BASED(cleanup_table_sysc_tif)
980	la	%r12,__LC_RETURN_PSW
981	br	%r14
982
983cleanup_sysc_restore:
984	clc	4(4,%r12),BASED(cleanup_sysc_restore_insn)
985	be	BASED(2f)
986	mvc	__LC_EXIT_TIMER(8),__LC_MCCK_ENTER_TIMER
987	c	%r12,BASED(.Lmck_old_psw)
988	be	BASED(0f)
989	mvc	__LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER
9900:	clc	4(4,%r12),BASED(cleanup_sysc_restore_insn+4)
991	be	BASED(2f)
992	mvc	__LC_RETURN_PSW(8),SP_PSW(%r15)
993	c	%r12,BASED(.Lmck_old_psw)
994	la	%r12,__LC_SAVE_AREA+32
995	be	BASED(1f)
996	la	%r12,__LC_SAVE_AREA+16
9971:	mvc	0(16,%r12),SP_R12(%r15)
998	lm	%r0,%r11,SP_R0(%r15)
999	l	%r15,SP_R15(%r15)
10002:	la	%r12,__LC_RETURN_PSW
1001	br	%r14
1002cleanup_sysc_restore_insn:
1003	.long	sysc_done - 4 + 0x80000000
1004	.long	sysc_done - 8 + 0x80000000
1005
1006cleanup_io_tif:
1007	mvc	__LC_RETURN_PSW(4),0(%r12)
1008	mvc	__LC_RETURN_PSW+4(4),BASED(cleanup_table_io_tif)
1009	la	%r12,__LC_RETURN_PSW
1010	br	%r14
1011
1012cleanup_io_restore:
1013	clc	4(4,%r12),BASED(cleanup_io_restore_insn)
1014	be	BASED(1f)
1015	mvc	__LC_EXIT_TIMER(8),__LC_MCCK_ENTER_TIMER
1016	clc	4(4,%r12),BASED(cleanup_io_restore_insn+4)
1017	be	BASED(1f)
1018	mvc	__LC_RETURN_PSW(8),SP_PSW(%r15)
1019	mvc	__LC_SAVE_AREA+32(16),SP_R12(%r15)
1020	lm	%r0,%r11,SP_R0(%r15)
1021	l	%r15,SP_R15(%r15)
10221:	la	%r12,__LC_RETURN_PSW
1023	br	%r14
1024cleanup_io_restore_insn:
1025	.long	io_done - 4 + 0x80000000
1026	.long	io_done - 8 + 0x80000000
1027
1028/*
1029 * Integer constants
1030 */
1031		.align	4
1032.Lc_spsize:	.long	SP_SIZE
1033.Lc_overhead:	.long	STACK_FRAME_OVERHEAD
1034.Lnr_syscalls:	.long	NR_syscalls
1035.L0x018:	.short	0x018
1036.L0x020:	.short	0x020
1037.L0x028:	.short	0x028
1038.L0x030:	.short	0x030
1039.L0x038:	.short	0x038
1040.Lc_1:		.long	1
1041
1042/*
1043 * Symbol constants
1044 */
1045.Ls390_mcck:	.long	s390_do_machine_check
1046.Ls390_handle_mcck:
1047		.long	s390_handle_mcck
1048.Lmck_old_psw:	.long	__LC_MCK_OLD_PSW
1049.Ldo_IRQ:	.long	do_IRQ
1050.Ldo_extint:	.long	do_extint
1051.Ldo_signal:	.long	do_signal
1052.Ldo_notify_resume:
1053		.long	do_notify_resume
1054.Lhandle_per:	.long	do_single_step
1055.Ldo_execve:	.long	do_execve
1056.Lexecve_tail:	.long	execve_tail
1057.Ljump_table:	.long	pgm_check_table
1058.Lschedule:	.long	schedule
1059#ifdef CONFIG_PREEMPT
1060.Lpreempt_schedule_irq:
1061		.long	preempt_schedule_irq
1062#endif
1063.Ltrace_entry:	.long	do_syscall_trace_enter
1064.Ltrace_exit:	.long	do_syscall_trace_exit
1065.Lschedtail:	.long	schedule_tail
1066.Lsysc_table:	.long	sys_call_table
1067#ifdef CONFIG_TRACE_IRQFLAGS
1068.Ltrace_irq_on_caller:
1069		.long	trace_hardirqs_on_caller
1070.Ltrace_irq_off_caller:
1071		.long	trace_hardirqs_off_caller
1072#endif
1073#ifdef CONFIG_LOCKDEP
1074.Llockdep_sys_exit:
1075		.long	lockdep_sys_exit
1076#endif
1077.Lcritical_start:
1078		.long	__critical_start + 0x80000000
1079.Lcritical_end:
1080		.long	__critical_end + 0x80000000
1081.Lcleanup_critical:
1082		.long	cleanup_critical
1083
1084		.section .rodata, "a"
1085#define SYSCALL(esa,esame,emu)	.long esa
1086	.globl	sys_call_table
1087sys_call_table:
1088#include "syscalls.S"
1089#undef SYSCALL
1090