entry64.S 29 KB
Newer Older
Linus Torvalds's avatar
Linus Torvalds committed
1
/*
2
 *  arch/s390/kernel/entry64.S
Linus Torvalds's avatar
Linus Torvalds committed
3
4
 *    S390 low-level entry points.
 *
5
 *    Copyright (C) IBM Corp. 1999,2006
Linus Torvalds's avatar
Linus Torvalds committed
6
 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
Heiko Carstens's avatar
Heiko Carstens committed
7
8
 *		 Hartmut Penner (hp@de.ibm.com),
 *		 Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
9
 *		 Heiko Carstens <heiko.carstens@de.ibm.com>
Linus Torvalds's avatar
Linus Torvalds committed
10
11
12
13
14
15
16
17
18
 */

#include <linux/sys.h>
#include <linux/linkage.h>
#include <asm/cache.h>
#include <asm/lowcore.h>
#include <asm/errno.h>
#include <asm/ptrace.h>
#include <asm/thread_info.h>
19
#include <asm/asm-offsets.h>
Linus Torvalds's avatar
Linus Torvalds committed
20
21
22
23
24
25
26
#include <asm/unistd.h>
#include <asm/page.h>

/*
 * Stack layout for the system_call stack entry.
 * The first few entries are identical to the user_regs_struct.
 */
Heiko Carstens's avatar
Heiko Carstens committed
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
SP_PTREGS    =	STACK_FRAME_OVERHEAD
SP_ARGS      =	STACK_FRAME_OVERHEAD + __PT_ARGS
SP_PSW	     =	STACK_FRAME_OVERHEAD + __PT_PSW
SP_R0	     =	STACK_FRAME_OVERHEAD + __PT_GPRS
SP_R1	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 8
SP_R2	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 16
SP_R3	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 24
SP_R4	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 32
SP_R5	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 40
SP_R6	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 48
SP_R7	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 56
SP_R8	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 64
SP_R9	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 72
SP_R10	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 80
SP_R11	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 88
SP_R12	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 96
SP_R13	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 104
SP_R14	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 112
SP_R15	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 120
SP_ORIG_R2   =	STACK_FRAME_OVERHEAD + __PT_ORIG_GPR2
SP_ILC	     =	STACK_FRAME_OVERHEAD + __PT_ILC
SP_TRAP      =	STACK_FRAME_OVERHEAD + __PT_TRAP
SP_SIZE      =	STACK_FRAME_OVERHEAD + __PT_SIZE
Linus Torvalds's avatar
Linus Torvalds committed
50
51
52
53

STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
STACK_SIZE  = 1 << STACK_SHIFT

54
55
56
57
_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK | _TIF_NEED_RESCHED | \
		 _TIF_MCCK_PENDING | _TIF_RESTART_SVC | _TIF_SINGLE_STEP )
_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK | _TIF_NEED_RESCHED | \
		 _TIF_MCCK_PENDING)
Linus Torvalds's avatar
Linus Torvalds committed
58
59
60

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

61
62
63
64
65
66
67
68
#ifdef CONFIG_TRACE_IRQFLAGS
	.macro	TRACE_IRQS_ON
	 brasl	%r14,trace_hardirqs_on
	.endm

	.macro	TRACE_IRQS_OFF
	 brasl	%r14,trace_hardirqs_off
	.endm
69
70
71
72

	.macro	LOCKDEP_SYS_EXIT
	 brasl	%r14,lockdep_sys_exit
	.endm
73
74
75
#else
#define TRACE_IRQS_ON
#define TRACE_IRQS_OFF
76
#define LOCKDEP_SYS_EXIT
77
78
#endif

Heiko Carstens's avatar
Heiko Carstens committed
79
	.macro	STORE_TIMER lc_offset
Linus Torvalds's avatar
Linus Torvalds committed
80
81
82
83
84
85
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
	stpt	\lc_offset
#endif
	.endm

#ifdef CONFIG_VIRT_CPU_ACCOUNTING
Heiko Carstens's avatar
Heiko Carstens committed
86
	.macro	UPDATE_VTIME lc_from,lc_to,lc_sum
Linus Torvalds's avatar
Linus Torvalds committed
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
	lg	%r10,\lc_from
	slg	%r10,\lc_to
	alg	%r10,\lc_sum
	stg	%r10,\lc_sum
	.endm
#endif

/*
 * Register usage in interrupt handlers:
 *    R9  - pointer to current task structure
 *    R13 - pointer to literal pool
 *    R14 - return register for function calls
 *    R15 - kernel stack pointer
 */

Heiko Carstens's avatar
Heiko Carstens committed
102
	.macro	SAVE_ALL_BASE savearea
Linus Torvalds's avatar
Linus Torvalds committed
103
104
105
106
	stmg	%r12,%r15,\savearea
	larl	%r13,system_call
	.endm

107
108
109
110
111
	.macro	SAVE_ALL_SVC psworg,savearea
	la	%r12,\psworg
	lg	%r15,__LC_KERNEL_STACK	# problem state -> load ksp
	.endm

112
	.macro	SAVE_ALL_SYNC psworg,savearea
Linus Torvalds's avatar
Linus Torvalds committed
113
114
115
116
	la	%r12,\psworg
	tm	\psworg+1,0x01		# test problem state bit
	jz	2f			# skip stack setup save
	lg	%r15,__LC_KERNEL_STACK	# problem state -> load ksp
117
118
119
120
121
122
123
124
125
126
127
#ifdef CONFIG_CHECK_STACK
	j	3f
2:	tml	%r15,STACK_SIZE - CONFIG_STACK_GUARD
	jz	stack_overflow
3:
#endif
2:
	.endm

	.macro	SAVE_ALL_ASYNC psworg,savearea
	la	%r12,\psworg
Linus Torvalds's avatar
Linus Torvalds committed
128
129
130
131
132
133
134
	tm	\psworg+1,0x01		# test problem state bit
	jnz	1f			# from user -> load kernel stack
	clc	\psworg+8(8),BASED(.Lcritical_end)
	jhe	0f
	clc	\psworg+8(8),BASED(.Lcritical_start)
	jl	0f
	brasl	%r14,cleanup_critical
135
	tm	1(%r12),0x01		# retest problem state after cleanup
Linus Torvalds's avatar
Linus Torvalds committed
136
137
138
139
140
141
142
143
144
145
146
147
	jnz	1f
0:	lg	%r14,__LC_ASYNC_STACK	# are we already on the async. stack ?
	slgr	%r14,%r15
	srag	%r14,%r14,STACK_SHIFT
	jz	2f
1:	lg	%r15,__LC_ASYNC_STACK	# load async stack
#ifdef CONFIG_CHECK_STACK
	j	3f
2:	tml	%r15,STACK_SIZE - CONFIG_STACK_GUARD
	jz	stack_overflow
3:
#endif
148
149
150
151
2:
	.endm

	.macro	CREATE_STACK_FRAME psworg,savearea
Heiko Carstens's avatar
Heiko Carstens committed
152
153
	aghi	%r15,-SP_SIZE		# make room for registers & psw
	mvc	SP_PSW(16,%r15),0(%r12)	# move user PSW to stack
Linus Torvalds's avatar
Linus Torvalds committed
154
155
156
157
158
159
160
161
	la	%r12,\psworg
	stg	%r2,SP_ORIG_R2(%r15)	# store original content of gpr 2
	icm	%r12,12,__LC_SVC_ILC
	stmg	%r0,%r11,SP_R0(%r15)	# store gprs %r0-%r11 to kernel stack
	st	%r12,SP_ILC(%r15)
	mvc	SP_R12(32,%r15),\savearea # move %r12-%r15 to stack
	la	%r12,0
	stg	%r12,__SF_BACKCHAIN(%r15)
Heiko Carstens's avatar
Heiko Carstens committed
162
	.endm
Linus Torvalds's avatar
Linus Torvalds committed
163

164
165
	.macro	RESTORE_ALL psworg,sync
	mvc	\psworg(16),SP_PSW(%r15) # move user PSW to lowcore
Linus Torvalds's avatar
Linus Torvalds committed
166
	.if !\sync
167
	ni	\psworg+1,0xfd		# clear wait state bit
Linus Torvalds's avatar
Linus Torvalds committed
168
169
170
	.endif
	lmg	%r0,%r15,SP_R0(%r15)	# load gprs 0-15 of user
	STORE_TIMER __LC_EXIT_TIMER
171
	lpswe	\psworg			# back to caller
Linus Torvalds's avatar
Linus Torvalds committed
172
173
174
175
176
177
178
179
180
	.endm

/*
 * Scheduler resume function, called by switch_to
 *  gpr2 = (task_struct *) prev
 *  gpr3 = (task_struct *) next
 * Returns:
 *  gpr2 = prev
 */
Heiko Carstens's avatar
Heiko Carstens committed
181
	.globl	__switch_to
Linus Torvalds's avatar
Linus Torvalds committed
182
183
184
__switch_to:
	tm	__THREAD_per+4(%r3),0xe8 # is the new process using per ?
	jz	__switch_to_noper		# if not we're fine
Heiko Carstens's avatar
Heiko Carstens committed
185
186
187
188
	stctg	%c9,%c11,__SF_EMPTY(%r15)# We are using per stuff
	clc	__THREAD_per(24,%r3),__SF_EMPTY(%r15)
	je	__switch_to_noper	     # we got away without bashing TLB's
	lctlg	%c9,%c11,__THREAD_per(%r3)	# Nope we didn't
Linus Torvalds's avatar
Linus Torvalds committed
189
__switch_to_noper:
Heiko Carstens's avatar
Heiko Carstens committed
190
	lg	%r4,__THREAD_info(%r2)		    # get thread_info of prev
191
192
193
194
195
196
	tm	__TI_flags+7(%r4),_TIF_MCCK_PENDING # machine check pending?
	jz	__switch_to_no_mcck
	ni	__TI_flags+7(%r4),255-_TIF_MCCK_PENDING # clear flag in prev
	lg	%r4,__THREAD_info(%r3)		    # get thread_info of next
	oi	__TI_flags+7(%r4),_TIF_MCCK_PENDING # set it in next
__switch_to_no_mcck:
Heiko Carstens's avatar
Heiko Carstens committed
197
	stmg	%r6,%r15,__SF_GPRS(%r15)# store __switch_to registers of prev task
Linus Torvalds's avatar
Linus Torvalds committed
198
199
	stg	%r15,__THREAD_ksp(%r2)	# store kernel stack to prev->tss.ksp
	lg	%r15,__THREAD_ksp(%r3)	# load kernel stack from next->tss.ksp
Heiko Carstens's avatar
Heiko Carstens committed
200
	lmg	%r6,%r15,__SF_GPRS(%r15)# load __switch_to registers of next task
Linus Torvalds's avatar
Linus Torvalds committed
201
202
	stg	%r3,__LC_CURRENT	# __LC_CURRENT = current task struct
	lctl	%c4,%c4,__TASK_pid(%r3) # load pid to control reg. 4
Heiko Carstens's avatar
Heiko Carstens committed
203
	lg	%r3,__THREAD_info(%r3)	# load thread_info from task struct
Linus Torvalds's avatar
Linus Torvalds committed
204
205
206
207
208
209
210
211
212
213
214
	stg	%r3,__LC_THREAD_INFO
	aghi	%r3,STACK_SIZE
	stg	%r3,__LC_KERNEL_STACK	# __LC_KERNEL_STACK = new kernel stack
	br	%r14

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

Heiko Carstens's avatar
Heiko Carstens committed
215
	.globl	system_call
Linus Torvalds's avatar
Linus Torvalds committed
216
217
218
219
system_call:
	STORE_TIMER __LC_SYNC_ENTER_TIMER
sysc_saveall:
	SAVE_ALL_BASE __LC_SAVE_AREA
220
	SAVE_ALL_SVC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
Heiko Carstens's avatar
Heiko Carstens committed
221
222
	CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
	llgh	%r7,__LC_SVC_INT_CODE	# get svc number from lowcore
Linus Torvalds's avatar
Linus Torvalds committed
223
224
225
226
227
228
229
230
231
232
233
234
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
sysc_vtime:
	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
	jz	sysc_do_svc
	UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
sysc_stime:
	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
sysc_update:
	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
#endif
sysc_do_svc:
	lg	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
Heiko Carstens's avatar
Heiko Carstens committed
235
	slag	%r7,%r7,2	# *4 and test for svc 0
Linus Torvalds's avatar
Linus Torvalds committed
236
237
238
239
	jnz	sysc_nr_ok
	# svc 0: system call number in %r1
	cl	%r1,BASED(.Lnr_syscalls)
	jnl	sysc_nr_ok
Heiko Carstens's avatar
Heiko Carstens committed
240
241
	lgfr	%r7,%r1 	# clear high word in r1
	slag	%r7,%r7,2	# svc 0: system call number in %r1
Linus Torvalds's avatar
Linus Torvalds committed
242
243
244
sysc_nr_ok:
	mvc	SP_ARGS(8,%r15),SP_R7(%r15)
sysc_do_restart:
Heiko Carstens's avatar
Heiko Carstens committed
245
	larl	%r10,sys_call_table
246
#ifdef CONFIG_COMPAT
247
248
	tm	__TI_flags+5(%r9),(_TIF_31BIT>>16)  # running in 31 bit mode ?
	jno	sysc_noemu
Heiko Carstens's avatar
Heiko Carstens committed
249
	larl	%r10,sys_call_table_emu  # use 31 bit emulation system calls
Linus Torvalds's avatar
Linus Torvalds committed
250
251
252
sysc_noemu:
#endif
	tm	__TI_flags+7(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
Heiko Carstens's avatar
Heiko Carstens committed
253
254
255
256
	lgf	%r8,0(%r7,%r10) # load address of system call routine
	jnz	sysc_tracesys
	basr	%r14,%r8	# call sys_xxxx
	stg	%r2,SP_R2(%r15) # store return value (change R2 on stack)
Linus Torvalds's avatar
Linus Torvalds committed
257
258

sysc_return:
Heiko Carstens's avatar
Heiko Carstens committed
259
260
	tm	SP_PSW+1(%r15),0x01	# returning to user ?
	jno	sysc_leave
Linus Torvalds's avatar
Linus Torvalds committed
261
	tm	__TI_flags+7(%r9),_TIF_WORK_SVC
Heiko Carstens's avatar
Heiko Carstens committed
262
	jnz	sysc_work	# there is work to do (signals etc.)
263
	LOCKDEP_SYS_EXIT
Linus Torvalds's avatar
Linus Torvalds committed
264
sysc_leave:
Heiko Carstens's avatar
Heiko Carstens committed
265
	RESTORE_ALL __LC_RETURN_PSW,1
Linus Torvalds's avatar
Linus Torvalds committed
266
267
268
269
270
271

#
# recheck if there is more work to do
#
sysc_work_loop:
	tm	__TI_flags+7(%r9),_TIF_WORK_SVC
Heiko Carstens's avatar
Heiko Carstens committed
272
	jz	sysc_leave	  # there is no work to do
Linus Torvalds's avatar
Linus Torvalds committed
273
274
275
276
#
# One of the work bits is on. Find out which one.
#
sysc_work:
277
278
	tm	__TI_flags+7(%r9),_TIF_MCCK_PENDING
	jo	sysc_mcck_pending
Linus Torvalds's avatar
Linus Torvalds committed
279
280
	tm	__TI_flags+7(%r9),_TIF_NEED_RESCHED
	jo	sysc_reschedule
281
282
	tm	__TI_flags+7(%r9),(_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK)
	jnz	sysc_sigpending
Linus Torvalds's avatar
Linus Torvalds committed
283
284
285
286
	tm	__TI_flags+7(%r9),_TIF_RESTART_SVC
	jo	sysc_restart
	tm	__TI_flags+7(%r9),_TIF_SINGLE_STEP
	jo	sysc_singlestep
287
	LOCKDEP_SYS_EXIT
Linus Torvalds's avatar
Linus Torvalds committed
288
289
290
291
	j	sysc_leave

#
# _TIF_NEED_RESCHED is set, call schedule
Heiko Carstens's avatar
Heiko Carstens committed
292
293
294
295
#
sysc_reschedule:
	larl	%r14,sysc_work_loop
	jg	schedule	# return point is sysc_return
Linus Torvalds's avatar
Linus Torvalds committed
296

297
298
299
300
301
#
# _TIF_MCCK_PENDING is set, call handler
#
sysc_mcck_pending:
	larl	%r14,sysc_work_loop
Heiko Carstens's avatar
Heiko Carstens committed
302
	jg	s390_handle_mcck	# TIF bit will be cleared by handler
303

Linus Torvalds's avatar
Linus Torvalds committed
304
#
305
# _TIF_SIGPENDING or _TIF_RESTORE_SIGMASK is set, call do_signal
Linus Torvalds's avatar
Linus Torvalds committed
306
#
Heiko Carstens's avatar
Heiko Carstens committed
307
sysc_sigpending:
Linus Torvalds's avatar
Linus Torvalds committed
308
	ni	__TI_flags+7(%r9),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
Heiko Carstens's avatar
Heiko Carstens committed
309
310
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
	brasl	%r14,do_signal		# call do_signal
Linus Torvalds's avatar
Linus Torvalds committed
311
312
313
314
	tm	__TI_flags+7(%r9),_TIF_RESTART_SVC
	jo	sysc_restart
	tm	__TI_flags+7(%r9),_TIF_SINGLE_STEP
	jo	sysc_singlestep
Heiko Carstens's avatar
Heiko Carstens committed
315
	j	sysc_work_loop
Linus Torvalds's avatar
Linus Torvalds committed
316
317
318
319
320
321

#
# _TIF_RESTART_SVC is set, set up registers and restart svc
#
sysc_restart:
	ni	__TI_flags+7(%r9),255-_TIF_RESTART_SVC # clear TIF_RESTART_SVC
Heiko Carstens's avatar
Heiko Carstens committed
322
323
	lg	%r7,SP_R2(%r15)		# load new svc number
	slag	%r7,%r7,2		# *4
Linus Torvalds's avatar
Linus Torvalds committed
324
	mvc	SP_R2(8,%r15),SP_ORIG_R2(%r15) # restore first argument
Heiko Carstens's avatar
Heiko Carstens committed
325
326
	lmg	%r2,%r6,SP_R2(%r15)	# load svc arguments
	j	sysc_do_restart 	# restart svc
Linus Torvalds's avatar
Linus Torvalds committed
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343

#
# _TIF_SINGLE_STEP is set, call do_single_step
#
sysc_singlestep:
	ni	__TI_flags+7(%r9),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
	lhi	%r0,__LC_PGM_OLD_PSW
	sth	%r0,SP_TRAP(%r15)	# set trap indication to pgm check
	la	%r2,SP_PTREGS(%r15)	# address of register-save area
	larl	%r14,sysc_return	# load adr. of system return
	jg	do_single_step		# branch to do_sigtrap

#
# call syscall_trace before and after system call
# special linkage: %r12 contains the return address for trace_svc
#
sysc_tracesys:
Heiko Carstens's avatar
Heiko Carstens committed
344
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
Linus Torvalds's avatar
Linus Torvalds committed
345
346
	la	%r3,0
	srl	%r7,2
Heiko Carstens's avatar
Heiko Carstens committed
347
348
	stg	%r7,SP_R2(%r15)
	brasl	%r14,syscall_trace
Linus Torvalds's avatar
Linus Torvalds committed
349
350
351
	lghi	%r0,NR_syscalls
	clg	%r0,SP_R2(%r15)
	jnh	sysc_tracenogo
Heiko Carstens's avatar
Heiko Carstens committed
352
353
	lg	%r7,SP_R2(%r15)		# strace might have changed the
	sll	%r7,2			# system call
Linus Torvalds's avatar
Linus Torvalds committed
354
355
	lgf	%r8,0(%r7,%r10)
sysc_tracego:
Heiko Carstens's avatar
Heiko Carstens committed
356
357
358
359
	lmg	%r3,%r6,SP_R3(%r15)
	lg	%r2,SP_ORIG_R2(%r15)
	basr	%r14,%r8		# call sys_xxx
	stg	%r2,SP_R2(%r15)		# store return value
Linus Torvalds's avatar
Linus Torvalds committed
360
361
sysc_tracenogo:
	tm	__TI_flags+7(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
Heiko Carstens's avatar
Heiko Carstens committed
362
363
	jz	sysc_return
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
Linus Torvalds's avatar
Linus Torvalds committed
364
	la	%r3,1
Heiko Carstens's avatar
Heiko Carstens committed
365
	larl	%r14,sysc_return	# return point is sysc_return
Linus Torvalds's avatar
Linus Torvalds committed
366
367
368
369
370
	jg	syscall_trace

#
# a new process exits the kernel with ret_from_fork
#
Heiko Carstens's avatar
Heiko Carstens committed
371
	.globl	ret_from_fork
Linus Torvalds's avatar
Linus Torvalds committed
372
373
374
375
376
377
ret_from_fork:
	lg	%r13,__LC_SVC_NEW_PSW+8
	lg	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
	tm	SP_PSW+1(%r15),0x01	# forking a kernel thread ?
	jo	0f
	stg	%r15,SP_R15(%r15)	# store stack pointer for new kthread
Heiko Carstens's avatar
Heiko Carstens committed
378
0:	brasl	%r14,schedule_tail
379
	TRACE_IRQS_ON
Heiko Carstens's avatar
Heiko Carstens committed
380
	stosm	24(%r15),0x03		# reenable interrupts
Linus Torvalds's avatar
Linus Torvalds committed
381
382
383
	j	sysc_return

#
384
385
# kernel_execve function needs to deal with pt_regs that is not
# at the usual place
Linus Torvalds's avatar
Linus Torvalds committed
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
	.globl	kernel_execve
kernel_execve:
	stmg	%r12,%r15,96(%r15)
	lgr	%r14,%r15
	aghi	%r15,-SP_SIZE
	stg	%r14,__SF_BACKCHAIN(%r15)
	la	%r12,SP_PTREGS(%r15)
	xc	0(__PT_SIZE,%r12),0(%r12)
	lgr	%r5,%r12
	brasl	%r14,do_execve
	ltgfr	%r2,%r2
	je	0f
	aghi	%r15,SP_SIZE
	lmg	%r12,%r15,96(%r15)
	br	%r14
	# execve succeeded.
0:	stnsm	__SF_EMPTY(%r15),0xfc	# disable interrupts
	lg	%r15,__LC_KERNEL_STACK	# load ksp
	aghi	%r15,-SP_SIZE		# make room for registers & psw
	lg	%r13,__LC_SVC_NEW_PSW+8
	lg	%r9,__LC_THREAD_INFO
	mvc	SP_PTREGS(__PT_SIZE,%r15),0(%r12)	# copy pt_regs
	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
	brasl	%r14,execve_tail
	j	sysc_return
Linus Torvalds's avatar
Linus Torvalds committed
413
414
415
416
417

/*
 * Program check handler routine
 */

Heiko Carstens's avatar
Heiko Carstens committed
418
	.globl	pgm_check_handler
Linus Torvalds's avatar
Linus Torvalds committed
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
pgm_check_handler:
/*
 * First we need to check for a special case:
 * Single stepping an instruction that disables the PER event mask will
 * cause a PER event AFTER the mask has been set. Example: SVC or LPSW.
 * For a single stepped SVC the program check handler gets control after
 * the SVC new PSW has been loaded. But we want to execute the SVC first and
 * then handle the PER event. Therefore we update the SVC old PSW to point
 * to the pgm_check_handler and branch to the SVC handler after we checked
 * if we have to load the kernel stack register.
 * For every other possible cause for PER event without the PER mask set
 * we just ignore the PER event (FIXME: is there anything we have to do
 * for LPSW?).
 */
	STORE_TIMER __LC_SYNC_ENTER_TIMER
	SAVE_ALL_BASE __LC_SAVE_AREA
Heiko Carstens's avatar
Heiko Carstens committed
435
436
	tm	__LC_PGM_INT_CODE+1,0x80 # check whether we got a per exception
	jnz	pgm_per 		 # got per exception -> special case
437
	SAVE_ALL_SYNC __LC_PGM_OLD_PSW,__LC_SAVE_AREA
438
	CREATE_STACK_FRAME __LC_PGM_OLD_PSW,__LC_SAVE_AREA
Linus Torvalds's avatar
Linus Torvalds committed
439
440
441
442
443
444
445
446
447
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
	jz	pgm_no_vtime
	UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
pgm_no_vtime:
#endif
	lg	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
Heiko Carstens's avatar
Heiko Carstens committed
448
	lgf	%r3,__LC_PGM_ILC	# load program interruption code
Linus Torvalds's avatar
Linus Torvalds committed
449
450
451
	lghi	%r8,0x7f
	ngr	%r8,%r3
pgm_do_call:
Heiko Carstens's avatar
Heiko Carstens committed
452
453
454
455
	sll	%r8,3
	larl	%r1,pgm_check_table
	lg	%r1,0(%r8,%r1)		# load address of handler routine
	la	%r2,SP_PTREGS(%r15)	# address of register-save area
Linus Torvalds's avatar
Linus Torvalds committed
456
	larl	%r14,sysc_return
Heiko Carstens's avatar
Heiko Carstens committed
457
	br	%r1			# branch to interrupt-handler
Linus Torvalds's avatar
Linus Torvalds committed
458
459
460
461
462

#
# handle per exception
#
pgm_per:
Heiko Carstens's avatar
Heiko Carstens committed
463
464
	tm	__LC_PGM_OLD_PSW,0x40	# test if per event recording is on
	jnz	pgm_per_std		# ok, normal per event from user space
Linus Torvalds's avatar
Linus Torvalds committed
465
# ok its one of the special cases, now we need to find out which one
Heiko Carstens's avatar
Heiko Carstens committed
466
467
	clc	__LC_PGM_OLD_PSW(16),__LC_SVC_NEW_PSW
	je	pgm_svcper
Linus Torvalds's avatar
Linus Torvalds committed
468
469
# no interesting special case, ignore PER event
	lmg	%r12,%r15,__LC_SAVE_AREA
Heiko Carstens's avatar
Heiko Carstens committed
470
	lpswe	__LC_PGM_OLD_PSW
Linus Torvalds's avatar
Linus Torvalds committed
471
472
473
474
475

#
# Normal per exception
#
pgm_per_std:
476
	SAVE_ALL_SYNC __LC_PGM_OLD_PSW,__LC_SAVE_AREA
477
	CREATE_STACK_FRAME __LC_PGM_OLD_PSW,__LC_SAVE_AREA
Linus Torvalds's avatar
Linus Torvalds committed
478
479
480
481
482
483
484
485
486
487
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
	jz	pgm_no_vtime2
	UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
pgm_no_vtime2:
#endif
	lg	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
	lg	%r1,__TI_task(%r9)
Michael Grundy's avatar
Michael Grundy committed
488
489
	tm	SP_PSW+1(%r15),0x01	# kernel per event ?
	jz	kernel_per
Linus Torvalds's avatar
Linus Torvalds committed
490
491
492
493
	mvc	__THREAD_per+__PER_atmid(2,%r1),__LC_PER_ATMID
	mvc	__THREAD_per+__PER_address(8,%r1),__LC_PER_ADDRESS
	mvc	__THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID
	oi	__TI_flags+7(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
Heiko Carstens's avatar
Heiko Carstens committed
494
	lgf	%r3,__LC_PGM_ILC	# load program interruption code
Linus Torvalds's avatar
Linus Torvalds committed
495
	lghi	%r8,0x7f
Heiko Carstens's avatar
Heiko Carstens committed
496
	ngr	%r8,%r3			# clear per-event-bit and ilc
Linus Torvalds's avatar
Linus Torvalds committed
497
498
499
500
501
502
503
	je	sysc_return
	j	pgm_do_call

#
# it was a single stepped SVC that is causing all the trouble
#
pgm_svcper:
504
	SAVE_ALL_SYNC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
505
	CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
Linus Torvalds's avatar
Linus Torvalds committed
506
507
508
509
510
511
512
513
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
	jz	pgm_no_vtime3
	UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
pgm_no_vtime3:
#endif
Heiko Carstens's avatar
Heiko Carstens committed
514
	llgh	%r7,__LC_SVC_INT_CODE	# get svc number from lowcore
Linus Torvalds's avatar
Linus Torvalds committed
515
516
517
518
519
520
	lg	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
	lg	%r1,__TI_task(%r9)
	mvc	__THREAD_per+__PER_atmid(2,%r1),__LC_PER_ATMID
	mvc	__THREAD_per+__PER_address(8,%r1),__LC_PER_ADDRESS
	mvc	__THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID
	oi	__TI_flags+7(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
521
	TRACE_IRQS_ON
Linus Torvalds's avatar
Linus Torvalds committed
522
523
524
	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
	j	sysc_do_svc

Michael Grundy's avatar
Michael Grundy committed
525
526
527
528
529
530
531
532
533
534
#
# per was called from kernel, must be kprobes
#
kernel_per:
	lhi	%r0,__LC_PGM_OLD_PSW
	sth	%r0,SP_TRAP(%r15)	# set trap indication to pgm check
	la	%r2,SP_PTREGS(%r15)	# address of register-save area
	larl	%r14,sysc_leave		# load adr. of system ret, no work
	jg	do_single_step		# branch to do_single_step

Linus Torvalds's avatar
Linus Torvalds committed
535
536
537
/*
 * IO interrupt handler routine
 */
Heiko Carstens's avatar
Heiko Carstens committed
538
	.globl io_int_handler
Linus Torvalds's avatar
Linus Torvalds committed
539
540
541
542
io_int_handler:
	STORE_TIMER __LC_ASYNC_ENTER_TIMER
	stck	__LC_INT_CLOCK
	SAVE_ALL_BASE __LC_SAVE_AREA+32
543
	SAVE_ALL_ASYNC __LC_IO_OLD_PSW,__LC_SAVE_AREA+32
544
	CREATE_STACK_FRAME __LC_IO_OLD_PSW,__LC_SAVE_AREA+32
Linus Torvalds's avatar
Linus Torvalds committed
545
546
547
548
549
550
551
552
553
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
	jz	io_no_vtime
	UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
io_no_vtime:
#endif
	lg	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
554
	TRACE_IRQS_OFF
Heiko Carstens's avatar
Heiko Carstens committed
555
556
	la	%r2,SP_PTREGS(%r15)	# address of register-save area
	brasl	%r14,do_IRQ		# call standard irq handler
557
	TRACE_IRQS_ON
Linus Torvalds's avatar
Linus Torvalds committed
558
559

io_return:
Heiko Carstens's avatar
Heiko Carstens committed
560
	tm	SP_PSW+1(%r15),0x01	# returning to user ?
Linus Torvalds's avatar
Linus Torvalds committed
561
#ifdef CONFIG_PREEMPT
Heiko Carstens's avatar
Heiko Carstens committed
562
	jno	io_preempt		# no -> check for preemptive scheduling
Linus Torvalds's avatar
Linus Torvalds committed
563
#else
Heiko Carstens's avatar
Heiko Carstens committed
564
	jno	io_leave		# no-> skip resched & signal
Linus Torvalds's avatar
Linus Torvalds committed
565
566
#endif
	tm	__TI_flags+7(%r9),_TIF_WORK_INT
Heiko Carstens's avatar
Heiko Carstens committed
567
	jnz	io_work 		# there is work to do (signals etc.)
568
	LOCKDEP_SYS_EXIT
Linus Torvalds's avatar
Linus Torvalds committed
569
io_leave:
Heiko Carstens's avatar
Heiko Carstens committed
570
	RESTORE_ALL __LC_RETURN_PSW,0
571
io_done:
Linus Torvalds's avatar
Linus Torvalds committed
572
573
574

#ifdef CONFIG_PREEMPT
io_preempt:
Heiko Carstens's avatar
Heiko Carstens committed
575
576
	icm	%r0,15,__TI_precount(%r9)
	jnz	io_leave
Linus Torvalds's avatar
Linus Torvalds committed
577
578
579
580
	# switch to kernel stack
	lg	%r1,SP_R15(%r15)
	aghi	%r1,-SP_SIZE
	mvc	SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
Heiko Carstens's avatar
Heiko Carstens committed
581
	xc	__SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1) # clear back chain
Linus Torvalds's avatar
Linus Torvalds committed
582
583
584
585
	lgr	%r15,%r1
io_resume_loop:
	tm	__TI_flags+7(%r9),_TIF_NEED_RESCHED
	jno	io_leave
Heiko Carstens's avatar
Heiko Carstens committed
586
587
588
589
590
591
	larl	%r1,.Lc_pactive
	mvc	__TI_precount(4,%r9),0(%r1)
	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
	brasl	%r14,schedule		# call schedule
	stnsm	__SF_EMPTY(%r15),0xfc	# disable I/O and ext. interrupts
	xc	__TI_precount(4,%r9),__TI_precount(%r9)
Linus Torvalds's avatar
Linus Torvalds committed
592
593
594
595
596
597
598
599
600
601
	j	io_resume_loop
#endif

#
# switch to kernel stack, then check TIF bits
#
io_work:
	lg	%r1,__LC_KERNEL_STACK
	aghi	%r1,-SP_SIZE
	mvc	SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
Heiko Carstens's avatar
Heiko Carstens committed
602
	xc	__SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1) # clear back chain
Linus Torvalds's avatar
Linus Torvalds committed
603
604
605
	lgr	%r15,%r1
#
# One of the work bits is on. Find out which one.
606
607
# Checked are: _TIF_SIGPENDING, _TIF_RESTORE_SIGPENDING, _TIF_NEED_RESCHED
#	       and _TIF_MCCK_PENDING
Linus Torvalds's avatar
Linus Torvalds committed
608
609
#
io_work_loop:
610
611
	tm	__TI_flags+7(%r9),_TIF_MCCK_PENDING
	jo	io_mcck_pending
Linus Torvalds's avatar
Linus Torvalds committed
612
613
	tm	__TI_flags+7(%r9),_TIF_NEED_RESCHED
	jo	io_reschedule
614
615
	tm	__TI_flags+7(%r9),(_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK)
	jnz	io_sigpending
616
	LOCKDEP_SYS_EXIT
Linus Torvalds's avatar
Linus Torvalds committed
617
618
	j	io_leave

619
620
621
622
#
# _TIF_MCCK_PENDING is set, call handler
#
io_mcck_pending:
Heiko Carstens's avatar
Heiko Carstens committed
623
624
625
626
	TRACE_IRQS_OFF
	brasl	%r14,s390_handle_mcck	# TIF bit will be cleared by handler
	TRACE_IRQS_ON
	j	io_work_loop
627

Linus Torvalds's avatar
Linus Torvalds committed
628
629
#
# _TIF_NEED_RESCHED is set, call schedule
Heiko Carstens's avatar
Heiko Carstens committed
630
631
632
633
634
#
io_reschedule:
	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
	brasl	%r14,schedule		# call scheduler
	stnsm	__SF_EMPTY(%r15),0xfc	# disable I/O and ext. interrupts
Linus Torvalds's avatar
Linus Torvalds committed
635
636
637
638
639
	tm	__TI_flags+7(%r9),_TIF_WORK_INT
	jz	io_leave		# there is no work to do
	j	io_work_loop

#
640
# _TIF_SIGPENDING or _TIF_RESTORE_SIGMASK is set, call do_signal
Linus Torvalds's avatar
Linus Torvalds committed
641
#
Heiko Carstens's avatar
Heiko Carstens committed
642
643
644
io_sigpending:
	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
Linus Torvalds's avatar
Linus Torvalds committed
645
	brasl	%r14,do_signal		# call do_signal
Heiko Carstens's avatar
Heiko Carstens committed
646
	stnsm	__SF_EMPTY(%r15),0xfc	# disable I/O and ext. interrupts
Heiko Carstens's avatar
Heiko Carstens committed
647
	j	io_work_loop
Linus Torvalds's avatar
Linus Torvalds committed
648
649
650
651

/*
 * External interrupt handler routine
 */
Heiko Carstens's avatar
Heiko Carstens committed
652
	.globl	ext_int_handler
Linus Torvalds's avatar
Linus Torvalds committed
653
654
655
656
ext_int_handler:
	STORE_TIMER __LC_ASYNC_ENTER_TIMER
	stck	__LC_INT_CLOCK
	SAVE_ALL_BASE __LC_SAVE_AREA+32
657
	SAVE_ALL_ASYNC __LC_EXT_OLD_PSW,__LC_SAVE_AREA+32
658
	CREATE_STACK_FRAME __LC_EXT_OLD_PSW,__LC_SAVE_AREA+32
Linus Torvalds's avatar
Linus Torvalds committed
659
660
661
662
663
664
665
666
667
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
	jz	ext_no_vtime
	UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
ext_no_vtime:
#endif
	lg	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
668
	TRACE_IRQS_OFF
Heiko Carstens's avatar
Heiko Carstens committed
669
670
671
	la	%r2,SP_PTREGS(%r15)	# address of register-save area
	llgh	%r3,__LC_EXT_INT_CODE	# get interruption code
	brasl	%r14,do_extint
672
	TRACE_IRQS_ON
Linus Torvalds's avatar
Linus Torvalds committed
673
674
	j	io_return

675
676
__critical_end:

Linus Torvalds's avatar
Linus Torvalds committed
677
678
679
/*
 * Machine check handler routines
 */
Heiko Carstens's avatar
Heiko Carstens committed
680
	.globl mcck_int_handler
Linus Torvalds's avatar
Linus Torvalds committed
681
mcck_int_handler:
682
683
	la	%r1,4095		# revalidate r1
	spt	__LC_CPU_TIMER_SAVE_AREA-4095(%r1)	# revalidate cpu timer
Heiko Carstens's avatar
Heiko Carstens committed
684
	lmg	%r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r1)# revalidate gprs
Linus Torvalds's avatar
Linus Torvalds committed
685
	SAVE_ALL_BASE __LC_SAVE_AREA+64
686
	la	%r12,__LC_MCK_OLD_PSW
Heiko Carstens's avatar
Heiko Carstens committed
687
	tm	__LC_MCCK_CODE,0x80	# system damage?
688
	jo	mcck_int_main		# yes -> rest of mcck code invalid
Linus Torvalds's avatar
Linus Torvalds committed
689
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
	la	%r14,4095
	mvc	__LC_SAVE_AREA+104(8),__LC_ASYNC_ENTER_TIMER
	mvc	__LC_ASYNC_ENTER_TIMER(8),__LC_CPU_TIMER_SAVE_AREA-4095(%r14)
	tm	__LC_MCCK_CODE+5,0x02	# stored cpu timer value valid?
	jo	1f
	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	0f
	la	%r14,__LC_EXIT_TIMER
0:	clc	0(8,%r14),__LC_LAST_UPDATE_TIMER
	jl	0f
	la	%r14,__LC_LAST_UPDATE_TIMER
0:	spt	0(%r14)
	mvc	__LC_ASYNC_ENTER_TIMER(8),0(%r14)
1:
Linus Torvalds's avatar
Linus Torvalds committed
708
#endif
709
	tm	__LC_MCCK_CODE+2,0x09	# mwp + ia of old psw valid?
710
	jno	mcck_int_main		# no -> skip cleanup critical
Heiko Carstens's avatar
Heiko Carstens committed
711
	tm	__LC_MCK_OLD_PSW+1,0x01 # test problem state bit
712
713
714
	jnz	mcck_int_main		# from user -> load kernel stack
	clc	__LC_MCK_OLD_PSW+8(8),BASED(.Lcritical_end)
	jhe	mcck_int_main
Heiko Carstens's avatar
Heiko Carstens committed
715
	clc	__LC_MCK_OLD_PSW+8(8),BASED(.Lcritical_start)
716
	jl	mcck_int_main
Heiko Carstens's avatar
Heiko Carstens committed
717
	brasl	%r14,cleanup_critical
718
mcck_int_main:
Heiko Carstens's avatar
Heiko Carstens committed
719
	lg	%r14,__LC_PANIC_STACK	# are we already on the panic stack?
720
721
722
	slgr	%r14,%r15
	srag	%r14,%r14,PAGE_SHIFT
	jz	0f
Heiko Carstens's avatar
Heiko Carstens committed
723
	lg	%r15,__LC_PANIC_STACK	# load panic stack
724
0:	CREATE_STACK_FRAME __LC_MCK_OLD_PSW,__LC_SAVE_AREA+64
725
726
727
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
	tm	__LC_MCCK_CODE+2,0x08	# mwp of old psw valid?
	jno	mcck_no_vtime		# no -> no timer update
728
	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
729
730
731
732
733
734
	jz	mcck_no_vtime
	UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
mcck_no_vtime:
#endif
735
736
737
	lg	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
	brasl	%r14,s390_do_machine_check
Heiko Carstens's avatar
Heiko Carstens committed
738
	tm	SP_PSW+1(%r15),0x01	# returning to user ?
739
740
741
742
743
744
745
746
747
	jno	mcck_return
	lg	%r1,__LC_KERNEL_STACK	# switch to kernel stack
	aghi	%r1,-SP_SIZE
	mvc	SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
	xc	__SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1) # clear back chain
	lgr	%r15,%r1
	stosm	__SF_EMPTY(%r15),0x04	# turn dat on
	tm	__TI_flags+7(%r9),_TIF_MCCK_PENDING
	jno	mcck_return
748
	TRACE_IRQS_OFF
749
	brasl	%r14,s390_handle_mcck
750
	TRACE_IRQS_ON
Linus Torvalds's avatar
Linus Torvalds committed
751
mcck_return:
752
753
754
755
756
757
758
759
760
761
762
	mvc	__LC_RETURN_MCCK_PSW(16),SP_PSW(%r15) # move return PSW
	ni	__LC_RETURN_MCCK_PSW+1,0xfd # clear wait state bit
	lmg	%r0,%r15,SP_R0(%r15)	# load gprs 0-15
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
	mvc	__LC_ASYNC_ENTER_TIMER(8),__LC_SAVE_AREA+104
	tm	__LC_RETURN_MCCK_PSW+1,0x01 # returning to user ?
	jno	0f
	stpt	__LC_EXIT_TIMER
0:
#endif
	lpswe	__LC_RETURN_MCCK_PSW	# back to caller
Linus Torvalds's avatar
Linus Torvalds committed
763
764
765
766

/*
 * Restart interruption handler, kick starter for additional CPUs
 */
767
768
769
770
#ifdef CONFIG_SMP
#ifndef CONFIG_HOTPLUG_CPU
	.section .init.text,"ax"
#endif
Heiko Carstens's avatar
Heiko Carstens committed
771
	.globl restart_int_handler
Linus Torvalds's avatar
Linus Torvalds committed
772
restart_int_handler:
Heiko Carstens's avatar
Heiko Carstens committed
773
774
775
776
777
778
779
780
	lg	%r15,__LC_SAVE_AREA+120 # load ksp
	lghi	%r10,__LC_CREGS_SAVE_AREA
	lctlg	%c0,%c15,0(%r10) # get new ctl regs
	lghi	%r10,__LC_AREGS_SAVE_AREA
	lam	%a0,%a15,0(%r10)
	lmg	%r6,%r15,__SF_GPRS(%r15) # load registers from clone
	stosm	__SF_EMPTY(%r15),0x04	# now we can turn dat on
	jg	start_secondary
781
782
783
#ifndef CONFIG_HOTPLUG_CPU
	.previous
#endif
Linus Torvalds's avatar
Linus Torvalds committed
784
785
786
787
#else
/*
 * If we do not run with SMP enabled, let the new CPU crash ...
 */
Heiko Carstens's avatar
Heiko Carstens committed
788
	.globl restart_int_handler
Linus Torvalds's avatar
Linus Torvalds committed
789
restart_int_handler:
Heiko Carstens's avatar
Heiko Carstens committed
790
	basr	%r1,0
Linus Torvalds's avatar
Linus Torvalds committed
791
restart_base:
Heiko Carstens's avatar
Heiko Carstens committed
792
793
	lpswe	restart_crash-restart_base(%r1)
	.align 8
Linus Torvalds's avatar
Linus Torvalds committed
794
restart_crash:
Heiko Carstens's avatar
Heiko Carstens committed
795
	.long  0x000a0000,0x00000000,0x00000000,0x00000000
Linus Torvalds's avatar
Linus Torvalds committed
796
797
798
799
800
801
802
803
804
805
806
restart_go:
#endif

#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
807
	aghi	%r15,-SP_SIZE
Linus Torvalds's avatar
Linus Torvalds committed
808
809
810
811
812
813
814
	mvc	SP_PSW(16,%r15),0(%r12)	# move user PSW to stack
	stmg	%r0,%r11,SP_R0(%r15)	# store gprs %r0-%r11 to kernel stack
	la	%r1,__LC_SAVE_AREA
	chi	%r12,__LC_SVC_OLD_PSW
	je	0f
	chi	%r12,__LC_PGM_OLD_PSW
	je	0f
815
	la	%r1,__LC_SAVE_AREA+32
Heiko Carstens's avatar
Heiko Carstens committed
816
817
818
0:	mvc	SP_R12(32,%r15),0(%r1)	# move %r12-%r15 to stack
	xc	__SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) # clear back chain
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
Linus Torvalds's avatar
Linus Torvalds committed
819
820
821
822
823
824
825
826
827
828
829
	jg	kernel_stack_overflow
#endif

cleanup_table_system_call:
	.quad	system_call, sysc_do_svc
cleanup_table_sysc_return:
	.quad	sysc_return, sysc_leave
cleanup_table_sysc_leave:
	.quad	sysc_leave, sysc_work_loop
cleanup_table_sysc_work_loop:
	.quad	sysc_work_loop, sysc_reschedule
830
831
cleanup_table_io_return:
	.quad	io_return, io_leave
832
833
834
835
cleanup_table_io_leave:
	.quad	io_leave, io_done
cleanup_table_io_work_loop:
	.quad	io_work_loop, io_mcck_pending
Linus Torvalds's avatar
Linus Torvalds committed
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855

cleanup_critical:
	clc	8(8,%r12),BASED(cleanup_table_system_call)
	jl	0f
	clc	8(8,%r12),BASED(cleanup_table_system_call+8)
	jl	cleanup_system_call
0:
	clc	8(8,%r12),BASED(cleanup_table_sysc_return)
	jl	0f
	clc	8(8,%r12),BASED(cleanup_table_sysc_return+8)
	jl	cleanup_sysc_return
0:
	clc	8(8,%r12),BASED(cleanup_table_sysc_leave)
	jl	0f
	clc	8(8,%r12),BASED(cleanup_table_sysc_leave+8)
	jl	cleanup_sysc_leave
0:
	clc	8(8,%r12),BASED(cleanup_table_sysc_work_loop)
	jl	0f
	clc	8(8,%r12),BASED(cleanup_table_sysc_work_loop+8)
856
	jl	cleanup_sysc_return
857
858
859
860
861
0:
	clc	8(8,%r12),BASED(cleanup_table_io_return)
	jl	0f
	clc	8(8,%r12),BASED(cleanup_table_io_return+8)
	jl	cleanup_io_return
862
863
864
865
866
867
868
869
870
871
0:
	clc	8(8,%r12),BASED(cleanup_table_io_leave)
	jl	0f
	clc	8(8,%r12),BASED(cleanup_table_io_leave+8)
	jl	cleanup_io_leave
0:
	clc	8(8,%r12),BASED(cleanup_table_io_work_loop)
	jl	0f
	clc	8(8,%r12),BASED(cleanup_table_io_work_loop+8)
	jl	cleanup_io_return
Linus Torvalds's avatar
Linus Torvalds committed
872
873
874
875
876
0:
	br	%r14

cleanup_system_call:
	mvc	__LC_RETURN_PSW(16),0(%r12)
877
878
879
880
881
882
	cghi	%r12,__LC_MCK_OLD_PSW
	je	0f
	la	%r12,__LC_SAVE_AREA+32
	j	1f
0:	la	%r12,__LC_SAVE_AREA+64
1:
Linus Torvalds's avatar
Linus Torvalds committed
883
884
885
886
887
888
889
890
891
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
	clc	__LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn+8)
	jh	0f
	mvc	__LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER
0:	clc	__LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn+16)
	jhe	cleanup_vtime
#endif
	clc	__LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn)
	jh	0f
892
893
894
	mvc	__LC_SAVE_AREA(32),0(%r12)
0:	stg	%r13,8(%r12)
	stg	%r12,__LC_SAVE_AREA+96	# argh
895
	SAVE_ALL_SYNC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
896
	CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
897
898
	lg	%r12,__LC_SAVE_AREA+96	# argh
	stg	%r15,24(%r12)
Linus Torvalds's avatar
Linus Torvalds committed
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
	llgh	%r7,__LC_SVC_INT_CODE
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
cleanup_vtime:
	clc	__LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn+24)
	jhe	cleanup_stime
	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
	jz	cleanup_novtime
	UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
cleanup_stime:
	clc	__LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn+32)
	jh	cleanup_update
	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
cleanup_update:
	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
cleanup_novtime:
#endif
	mvc	__LC_RETURN_PSW+8(8),BASED(cleanup_table_system_call+8)
	la	%r12,__LC_RETURN_PSW
	br	%r14
cleanup_system_call_insn:
	.quad	sysc_saveall
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
Heiko Carstens's avatar
Heiko Carstens committed
921
922
923
924
	.quad	system_call
	.quad	sysc_vtime
	.quad	sysc_stime
	.quad	sysc_update
Linus Torvalds's avatar
Linus Torvalds committed
925
926
927
928
929
930
931
932
933
934
#endif

cleanup_sysc_return:
	mvc	__LC_RETURN_PSW(8),0(%r12)
	mvc	__LC_RETURN_PSW+8(8),BASED(cleanup_table_sysc_return)
	la	%r12,__LC_RETURN_PSW
	br	%r14

cleanup_sysc_leave:
	clc	8(8,%r12),BASED(cleanup_sysc_leave_insn)
935
	je	2f
Linus Torvalds's avatar
Linus Torvalds committed
936
937
938
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
	mvc	__LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER
	clc	8(8,%r12),BASED(cleanup_sysc_leave_insn+8)
939
	je	2f
Linus Torvalds's avatar
Linus Torvalds committed
940
941
#endif
	mvc	__LC_RETURN_PSW(16),SP_PSW(%r15)
942
943
944
945
946
947
	cghi	%r12,__LC_MCK_OLD_PSW
	jne	0f
	mvc	__LC_SAVE_AREA+64(32),SP_R12(%r15)
	j	1f
0:	mvc	__LC_SAVE_AREA+32(32),SP_R12(%r15)
1:	lmg	%r0,%r11,SP_R0(%r15)
Linus Torvalds's avatar
Linus Torvalds committed
948
	lg	%r15,SP_R15(%r15)
949
2:	la	%r12,__LC_RETURN_PSW
Linus Torvalds's avatar
Linus Torvalds committed
950
951
952
953
954
955
956
	br	%r14
cleanup_sysc_leave_insn:
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
	.quad	sysc_leave + 16
#endif
	.quad	sysc_leave + 12

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
cleanup_io_return:
	mvc	__LC_RETURN_PSW(8),0(%r12)
	mvc	__LC_RETURN_PSW+8(8),BASED(cleanup_table_io_work_loop)
	la	%r12,__LC_RETURN_PSW
	br	%r14

cleanup_io_leave:
	clc	8(8,%r12),BASED(cleanup_io_leave_insn)
	je	2f
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
	mvc	__LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER
	clc	8(8,%r12),BASED(cleanup_io_leave_insn+8)
	je	2f
#endif
	mvc	__LC_RETURN_PSW(16),SP_PSW(%r15)
	cghi	%r12,__LC_MCK_OLD_PSW
	jne	0f
	mvc	__LC_SAVE_AREA+64(32),SP_R12(%r15)
	j	1f
0:	mvc	__LC_SAVE_AREA+32(32),SP_R12(%r15)
1:	lmg	%r0,%r11,SP_R0(%r15)
	lg	%r15,SP_R15(%r15)
2:	la	%r12,__LC_RETURN_PSW
	br	%r14
cleanup_io_leave_insn:
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
	.quad	io_leave + 20
#endif
	.quad	io_leave + 16

Linus Torvalds's avatar
Linus Torvalds committed
987
988
989
/*
 * Integer constants
 */
Heiko Carstens's avatar
Heiko Carstens committed
990
		.align	4
Linus Torvalds's avatar
Linus Torvalds committed
991
.Lconst:
Heiko Carstens's avatar
Heiko Carstens committed
992
993
994
995
996
997
998
.Lc_pactive:	.long	PREEMPT_ACTIVE
.Lnr_syscalls:	.long	NR_syscalls
.L0x0130:	.short	0x130
.L0x0140:	.short	0x140
.L0x0150:	.short	0x150
.L0x0160:	.short	0x160
.L0x0170:	.short	0x170
Linus Torvalds's avatar
Linus Torvalds committed
999
.Lcritical_start:
Heiko Carstens's avatar
Heiko Carstens committed
1000
		.quad	__critical_start
Linus Torvalds's avatar
Linus Torvalds committed
1001
.Lcritical_end:
Heiko Carstens's avatar
Heiko Carstens committed
1002
		.quad	__critical_end
Linus Torvalds's avatar
Linus Torvalds committed
1003

Heiko Carstens's avatar
Heiko Carstens committed
1004
		.section .rodata, "a"
Linus Torvalds's avatar
Linus Torvalds committed
1005
1006
1007
1008
1009
#define SYSCALL(esa,esame,emu)	.long esame
sys_call_table:
#include "syscalls.S"
#undef SYSCALL

1010
#ifdef CONFIG_COMPAT
Linus Torvalds's avatar
Linus Torvalds committed
1011
1012
1013
1014
1015
1016

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