entry.S 31.6 KB
Newer Older
Linus Torvalds's avatar
Linus Torvalds committed
1 2 3 4
/*
 *  arch/s390/kernel/entry.S
 *    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
#include <linux/init.h>
13
#include <linux/linkage.h>
Linus Torvalds's avatar
Linus Torvalds committed
14 15 16 17
#include <asm/cache.h>
#include <asm/errno.h>
#include <asm/ptrace.h>
#include <asm/thread_info.h>
18
#include <asm/asm-offsets.h>
Linus Torvalds's avatar
Linus Torvalds committed
19 20 21 22 23 24 25
#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
26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46
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 + 4
SP_R2	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 8
SP_R3	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 12
SP_R4	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 16
SP_R5	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 20
SP_R6	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 24
SP_R7	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 28
SP_R8	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 32
SP_R9	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 36
SP_R10	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 40
SP_R11	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 44
SP_R12	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 48
SP_R13	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 52
SP_R14	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 56
SP_R15	     =	STACK_FRAME_OVERHEAD + __PT_GPRS + 60
SP_ORIG_R2   =	STACK_FRAME_OVERHEAD + __PT_ORIG_GPR2
SP_ILC	     =	STACK_FRAME_OVERHEAD + __PT_ILC
47
SP_SVCNR     =	STACK_FRAME_OVERHEAD + __PT_SVCNR
Heiko Carstens's avatar
Heiko Carstens committed
48
SP_SIZE      =	STACK_FRAME_OVERHEAD + __PT_SIZE
Linus Torvalds's avatar
Linus Torvalds committed
49

Martin Schwidefsky's avatar
Martin Schwidefsky committed
50
_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
Martin Schwidefsky's avatar
Martin Schwidefsky committed
51
		 _TIF_MCCK_PENDING | _TIF_RESTART_SVC | _TIF_PER_TRAP )
Martin Schwidefsky's avatar
Martin Schwidefsky committed
52
_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
53
		 _TIF_MCCK_PENDING)
54
_TIF_SYSCALL = (_TIF_SYSCALL_TRACE>>8 | _TIF_SYSCALL_AUDIT>>8 | \
55
		_TIF_SECCOMP>>8 | _TIF_SYSCALL_TRACEPOINT>>8)
Linus Torvalds's avatar
Linus Torvalds committed
56 57 58 59 60 61

STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
STACK_SIZE  = 1 << STACK_SHIFT

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

62 63
#ifdef CONFIG_TRACE_IRQFLAGS
	.macro	TRACE_IRQS_ON
64 65
	basr	%r2,%r0
	l	%r1,BASED(.Ltrace_irq_on_caller)
66 67 68 69
	basr	%r14,%r1
	.endm

	.macro	TRACE_IRQS_OFF
70 71
	basr	%r2,%r0
	l	%r1,BASED(.Ltrace_irq_off_caller)
72 73 74 75 76
	basr	%r14,%r1
	.endm
#else
#define TRACE_IRQS_ON
#define TRACE_IRQS_OFF
77 78 79 80 81 82 83 84 85 86 87
#endif

#ifdef CONFIG_LOCKDEP
	.macro	LOCKDEP_SYS_EXIT
	tm	SP_PSW+1(%r15),0x01	# returning to user ?
	jz	0f
	l	%r1,BASED(.Llockdep_sys_exit)
	basr	%r14,%r1
0:
	.endm
#else
88
#define LOCKDEP_SYS_EXIT
89 90
#endif

Linus Torvalds's avatar
Linus Torvalds committed
91 92 93 94 95 96 97 98
/*
 * 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
99
	.macro	UPDATE_VTIME lc_from,lc_to,lc_sum
Linus Torvalds's avatar
Linus Torvalds committed
100 101 102 103 104 105 106 107 108 109 110 111
	lm	%r10,%r11,\lc_from
	sl	%r10,\lc_to
	sl	%r11,\lc_to+4
	bc	3,BASED(0f)
	sl	%r10,BASED(.Lc_1)
0:	al	%r10,\lc_sum
	al	%r11,\lc_sum+4
	bc	12,BASED(1f)
	al	%r10,BASED(.Lc_1)
1:	stm	%r10,%r11,\lc_sum
	.endm

112
	.macro	SAVE_ALL_SVC psworg,savearea
Linus Torvalds's avatar
Linus Torvalds committed
113 114
	stm	%r12,%r15,\savearea
	l	%r13,__LC_SVC_NEW_PSW+4	# load &system_call to %r13
115 116
	l	%r15,__LC_KERNEL_STACK	# problem state -> load ksp
	s	%r15,BASED(.Lc_spsize)	# make room for registers & psw
Linus Torvalds's avatar
Linus Torvalds committed
117 118
	.endm

119 120 121
	.macro	SAVE_ALL_BASE savearea
	stm	%r12,%r15,\savearea
	l	%r13,__LC_SVC_NEW_PSW+4	# load &system_call to %r13
122 123
	.endm

124
	.macro	SAVE_ALL_PGM psworg,savearea
Linus Torvalds's avatar
Linus Torvalds committed
125
	tm	\psworg+1,0x01		# test problem state bit
126
#ifdef CONFIG_CHECK_STACK
127 128 129 130 131 132 133
	bnz	BASED(1f)
	tml	%r15,STACK_SIZE - CONFIG_STACK_GUARD
	bnz	BASED(2f)
	la	%r12,\psworg
	b	BASED(stack_overflow)
#else
	bz	BASED(2f)
134
#endif
135 136
1:	l	%r15,__LC_KERNEL_STACK	# problem state -> load ksp
2:	s	%r15,BASED(.Lc_spsize)	# make room for registers & psw
137 138 139
	.endm

	.macro	SAVE_ALL_ASYNC psworg,savearea
140 141
	stm	%r12,%r15,\savearea
	l	%r13,__LC_SVC_NEW_PSW+4	# load &system_call to %r13
142
	la	%r12,\psworg
Linus Torvalds's avatar
Linus Torvalds committed
143 144 145 146 147 148 149 150
	tm	\psworg+1,0x01		# test problem state bit
	bnz	BASED(1f)		# from user -> load async stack
	clc	\psworg+4(4),BASED(.Lcritical_end)
	bhe	BASED(0f)
	clc	\psworg+4(4),BASED(.Lcritical_start)
	bl	BASED(0f)
	l	%r14,BASED(.Lcleanup_critical)
	basr	%r14,%r14
151
	tm	1(%r12),0x01		# retest problem state after cleanup
Linus Torvalds's avatar
Linus Torvalds committed
152 153 154 155 156
	bnz	BASED(1f)
0:	l	%r14,__LC_ASYNC_STACK	# are we already on the async stack ?
	slr	%r14,%r15
	sra	%r14,STACK_SHIFT
#ifdef CONFIG_CHECK_STACK
157 158 159 160 161 162
	bnz	BASED(1f)
	tml	%r15,STACK_SIZE - CONFIG_STACK_GUARD
	bnz	BASED(2f)
	b	BASED(stack_overflow)
#else
	bz	BASED(2f)
Linus Torvalds's avatar
Linus Torvalds committed
163
#endif
164 165
1:	l	%r15,__LC_ASYNC_STACK
2:	s	%r15,BASED(.Lc_spsize)	# make room for registers & psw
166 167
	.endm

168 169
	.macro	CREATE_STACK_FRAME savearea
	xc	__SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
Linus Torvalds's avatar
Linus Torvalds committed
170 171
	st	%r2,SP_ORIG_R2(%r15)	# store original content of gpr 2
	mvc	SP_R12(16,%r15),\savearea # move %r12-%r15 to stack
172
	stm	%r0,%r11,SP_R0(%r15)	# store gprs %r0-%r11 to kernel stack
Linus Torvalds's avatar
Linus Torvalds committed
173 174
	.endm

Heiko Carstens's avatar
Heiko Carstens committed
175
	.macro	RESTORE_ALL psworg,sync
176
	mvc	\psworg(8),SP_PSW(%r15) # move user PSW to lowcore
Linus Torvalds's avatar
Linus Torvalds committed
177
	.if !\sync
178
	ni	\psworg+1,0xfd		# clear wait state bit
Linus Torvalds's avatar
Linus Torvalds committed
179 180
	.endif
	lm	%r0,%r15,SP_R0(%r15)	# load gprs 0-15 of user
181
	stpt	__LC_EXIT_TIMER
182
	lpsw	\psworg			# back to caller
Linus Torvalds's avatar
Linus Torvalds committed
183 184
	.endm

185 186 187 188 189 190
	.macro REENABLE_IRQS
	mvc	__SF_EMPTY(1,%r15),SP_PSW(%r15)
	ni	__SF_EMPTY(%r15),0xbf
	ssm	__SF_EMPTY(%r15)
	.endm

191 192
	.section .kprobes.text, "ax"

Linus Torvalds's avatar
Linus Torvalds committed
193 194 195 196 197 198 199
/*
 * Scheduler resume function, called by switch_to
 *  gpr2 = (task_struct *) prev
 *  gpr3 = (task_struct *) next
 * Returns:
 *  gpr2 = prev
 */
200
ENTRY(__switch_to)
Heiko Carstens's avatar
Heiko Carstens committed
201
	basr	%r1,0
Martin Schwidefsky's avatar
Martin Schwidefsky committed
202 203
0:	l	%r4,__THREAD_info(%r2)		# get thread_info of prev
	l	%r5,__THREAD_info(%r3)		# get thread_info of next
204
	tm	__TI_flags+3(%r4),_TIF_MCCK_PENDING # machine check pending?
Martin Schwidefsky's avatar
Martin Schwidefsky committed
205 206 207 208 209 210 211 212 213
	bz	1f-0b(%r1)
	ni	__TI_flags+3(%r4),255-_TIF_MCCK_PENDING	# clear flag in prev
	oi	__TI_flags+3(%r5),_TIF_MCCK_PENDING	# set it in next
1:	stm	%r6,%r15,__SF_GPRS(%r15)	# store gprs of prev task
	st	%r15,__THREAD_ksp(%r2)		# store kernel stack of prev
	l	%r15,__THREAD_ksp(%r3)		# load kernel stack of next
	lctl	%c4,%c4,__TASK_pid(%r3)		# load pid to control reg. 4
	lm	%r6,%r15,__SF_GPRS(%r15)	# load gprs of next task
	st	%r3,__LC_CURRENT		# store task struct of next
214
	mvc	__LC_CURRENT_PID(4,%r0),__TASK_pid(%r3)	# store pid of next
Martin Schwidefsky's avatar
Martin Schwidefsky committed
215 216 217
	st	%r5,__LC_THREAD_INFO		# store thread info of next
	ahi	%r5,STACK_SIZE			# end of kernel stack of next
	st	%r5,__LC_KERNEL_STACK		# store end of kernel stack
Linus Torvalds's avatar
Linus Torvalds committed
218 219 220 221 222 223 224 225
	br	%r14

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

226
ENTRY(system_call)
227
	stpt	__LC_SYNC_ENTER_TIMER
Linus Torvalds's avatar
Linus Torvalds committed
228
sysc_saveall:
229
	SAVE_ALL_SVC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
230 231 232 233
	CREATE_STACK_FRAME __LC_SAVE_AREA
	mvc	SP_PSW(8,%r15),__LC_SVC_OLD_PSW
	mvc	SP_ILC(4,%r15),__LC_SVC_ILC
	l	%r12,__LC_THREAD_INFO	# load pointer to thread_info struct
Linus Torvalds's avatar
Linus Torvalds committed
234 235 236 237 238 239 240
sysc_vtime:
	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
sysc_do_svc:
241 242
	xr	%r7,%r7
	icm	%r7,3,SP_SVCNR(%r15)	# load svc number and test for svc 0
Heiko Carstens's avatar
Heiko Carstens committed
243
	bnz	BASED(sysc_nr_ok)	# svc number > 0
Linus Torvalds's avatar
Linus Torvalds committed
244 245 246
	# svc 0: system call number in %r1
	cl	%r1,BASED(.Lnr_syscalls)
	bnl	BASED(sysc_nr_ok)
247
	sth	%r1,SP_SVCNR(%r15)
Heiko Carstens's avatar
Heiko Carstens committed
248
	lr	%r7,%r1 	  # copy svc number to %r7
Linus Torvalds's avatar
Linus Torvalds committed
249
sysc_nr_ok:
250
	sll	%r7,2		  # svc number *4
251 252
	l	%r10,BASED(.Lsysc_table)
	tm	__TI_flags+2(%r12),_TIF_SYSCALL
253
	mvc	SP_ARGS(4,%r15),SP_R7(%r15)
254
	l	%r8,0(%r7,%r10)	  # get system call addr.
Heiko Carstens's avatar
Heiko Carstens committed
255 256 257
	bnz	BASED(sysc_tracesys)
	basr	%r14,%r8	  # call sys_xxxx
	st	%r2,SP_R2(%r15)   # store return value (change R2 on stack)
Linus Torvalds's avatar
Linus Torvalds committed
258 259

sysc_return:
260 261
	LOCKDEP_SYS_EXIT
sysc_tif:
262
	tm	__TI_flags+3(%r12),_TIF_WORK_SVC
Linus Torvalds's avatar
Linus Torvalds committed
263
	bnz	BASED(sysc_work)  # there is work to do (signals etc.)
264
sysc_restore:
Heiko Carstens's avatar
Heiko Carstens committed
265
	RESTORE_ALL __LC_RETURN_PSW,1
266 267
sysc_done:

Linus Torvalds's avatar
Linus Torvalds committed
268
#
269
# There is work to do, but first we need to check if we return to userspace.
Linus Torvalds's avatar
Linus Torvalds committed
270 271
#
sysc_work:
272 273
	tm	SP_PSW+1(%r15),0x01	# returning to user ?
	bno	BASED(sysc_restore)
274 275 276 277

#
# One of the work bits is on. Find out which one.
#
278
sysc_work_tif:
279
	tm	__TI_flags+3(%r12),_TIF_MCCK_PENDING
280
	bo	BASED(sysc_mcck_pending)
281
	tm	__TI_flags+3(%r12),_TIF_NEED_RESCHED
Linus Torvalds's avatar
Linus Torvalds committed
282
	bo	BASED(sysc_reschedule)
283
	tm	__TI_flags+3(%r12),_TIF_SIGPENDING
284
	bo	BASED(sysc_sigpending)
285
	tm	__TI_flags+3(%r12),_TIF_NOTIFY_RESUME
286
	bo	BASED(sysc_notify_resume)
287
	tm	__TI_flags+3(%r12),_TIF_RESTART_SVC
Linus Torvalds's avatar
Linus Torvalds committed
288
	bo	BASED(sysc_restart)
Martin Schwidefsky's avatar
Martin Schwidefsky committed
289
	tm	__TI_flags+3(%r12),_TIF_PER_TRAP
Linus Torvalds's avatar
Linus Torvalds committed
290
	bo	BASED(sysc_singlestep)
291
	b	BASED(sysc_return)	# beware of critical section cleanup
Linus Torvalds's avatar
Linus Torvalds committed
292 293 294

#
# _TIF_NEED_RESCHED is set, call schedule
Heiko Carstens's avatar
Heiko Carstens committed
295 296 297
#
sysc_reschedule:
	l	%r1,BASED(.Lschedule)
298
	la	%r14,BASED(sysc_return)
Heiko Carstens's avatar
Heiko Carstens committed
299
	br	%r1			# call scheduler
Linus Torvalds's avatar
Linus Torvalds committed
300

301 302 303 304 305
#
# _TIF_MCCK_PENDING is set, call handler
#
sysc_mcck_pending:
	l	%r1,BASED(.Ls390_handle_mcck)
306
	la	%r14,BASED(sysc_return)
307 308
	br	%r1			# TIF bit will be cleared by handler

Linus Torvalds's avatar
Linus Torvalds committed
309
#
310
# _TIF_SIGPENDING is set, call do_signal
Linus Torvalds's avatar
Linus Torvalds committed
311
#
Heiko Carstens's avatar
Heiko Carstens committed
312
sysc_sigpending:
Martin Schwidefsky's avatar
Martin Schwidefsky committed
313
	ni	__TI_flags+3(%r12),255-_TIF_PER_TRAP # clear TIF_PER_TRAP
Heiko Carstens's avatar
Heiko Carstens committed
314 315 316
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
	l	%r1,BASED(.Ldo_signal)
	basr	%r14,%r1		# call do_signal
317
	tm	__TI_flags+3(%r12),_TIF_RESTART_SVC
Linus Torvalds's avatar
Linus Torvalds committed
318
	bo	BASED(sysc_restart)
Martin Schwidefsky's avatar
Martin Schwidefsky committed
319
	tm	__TI_flags+3(%r12),_TIF_PER_TRAP
Linus Torvalds's avatar
Linus Torvalds committed
320
	bo	BASED(sysc_singlestep)
321
	b	BASED(sysc_return)
Linus Torvalds's avatar
Linus Torvalds committed
322

Martin Schwidefsky's avatar
Martin Schwidefsky committed
323 324 325 326 327 328
#
# _TIF_NOTIFY_RESUME is set, call do_notify_resume
#
sysc_notify_resume:
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
	l	%r1,BASED(.Ldo_notify_resume)
329
	la	%r14,BASED(sysc_return)
Martin Schwidefsky's avatar
Martin Schwidefsky committed
330 331 332
	br	%r1			# call do_notify_resume


Linus Torvalds's avatar
Linus Torvalds committed
333 334 335 336
#
# _TIF_RESTART_SVC is set, set up registers and restart svc
#
sysc_restart:
337
	ni	__TI_flags+3(%r12),255-_TIF_RESTART_SVC # clear TIF_RESTART_SVC
Heiko Carstens's avatar
Heiko Carstens committed
338
	l	%r7,SP_R2(%r15) 	# load new svc number
Linus Torvalds's avatar
Linus Torvalds committed
339
	mvc	SP_R2(4,%r15),SP_ORIG_R2(%r15) # restore first argument
Heiko Carstens's avatar
Heiko Carstens committed
340
	lm	%r2,%r6,SP_R2(%r15)	# load svc arguments
341
	sth	%r7,SP_SVCNR(%r15)
342
	b	BASED(sysc_nr_ok)	# restart svc
Linus Torvalds's avatar
Linus Torvalds committed
343 344

#
Martin Schwidefsky's avatar
Martin Schwidefsky committed
345
# _TIF_PER_TRAP is set, call do_per_trap
Linus Torvalds's avatar
Linus Torvalds committed
346 347
#
sysc_singlestep:
Martin Schwidefsky's avatar
Martin Schwidefsky committed
348
	ni	__TI_flags+3(%r12),255-_TIF_PER_TRAP # clear TIF_PER_TRAP
349
	xc	SP_SVCNR(2,%r15),SP_SVCNR(%r15)		# clear svc number
Linus Torvalds's avatar
Linus Torvalds committed
350 351
	la	%r2,SP_PTREGS(%r15)	# address of register-save area
	l	%r1,BASED(.Lhandle_per)	# load adr. of per handler
352
	la	%r14,BASED(sysc_return)	# load adr. of system return
Martin Schwidefsky's avatar
Martin Schwidefsky committed
353
	br	%r1			# branch to do_per_trap
Linus Torvalds's avatar
Linus Torvalds committed
354 355

#
Martin Schwidefsky's avatar
Martin Schwidefsky committed
356 357
# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
# and after the system call
Linus Torvalds's avatar
Linus Torvalds committed
358 359
#
sysc_tracesys:
Martin Schwidefsky's avatar
Martin Schwidefsky committed
360
	l	%r1,BASED(.Ltrace_entry)
Heiko Carstens's avatar
Heiko Carstens committed
361
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
Linus Torvalds's avatar
Linus Torvalds committed
362
	la	%r3,0
363 364 365
	xr	%r0,%r0
	icm	%r0,3,SP_SVCNR(%r15)
	st	%r0,SP_R2(%r15)
Linus Torvalds's avatar
Linus Torvalds committed
366
	basr	%r14,%r1
Martin Schwidefsky's avatar
Martin Schwidefsky committed
367
	cl	%r2,BASED(.Lnr_syscalls)
Linus Torvalds's avatar
Linus Torvalds committed
368
	bnl	BASED(sysc_tracenogo)
Martin Schwidefsky's avatar
Martin Schwidefsky committed
369
	lr	%r7,%r2
370
	sll	%r7,2			# svc number *4
371
	l	%r8,0(%r7,%r10)
Linus Torvalds's avatar
Linus Torvalds committed
372 373
sysc_tracego:
	lm	%r3,%r6,SP_R3(%r15)
374
	mvc	SP_ARGS(4,%r15),SP_R7(%r15)
Linus Torvalds's avatar
Linus Torvalds committed
375
	l	%r2,SP_ORIG_R2(%r15)
Heiko Carstens's avatar
Heiko Carstens committed
376 377
	basr	%r14,%r8		# call sys_xxx
	st	%r2,SP_R2(%r15)		# store return value
Linus Torvalds's avatar
Linus Torvalds committed
378
sysc_tracenogo:
379
	tm	__TI_flags+2(%r12),_TIF_SYSCALL
Heiko Carstens's avatar
Heiko Carstens committed
380
	bz	BASED(sysc_return)
Martin Schwidefsky's avatar
Martin Schwidefsky committed
381
	l	%r1,BASED(.Ltrace_exit)
Heiko Carstens's avatar
Heiko Carstens committed
382
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
Linus Torvalds's avatar
Linus Torvalds committed
383 384 385 386 387 388
	la	%r14,BASED(sysc_return)
	br	%r1

#
# a new process exits the kernel with ret_from_fork
#
389
ENTRY(ret_from_fork)
Linus Torvalds's avatar
Linus Torvalds committed
390
	l	%r13,__LC_SVC_NEW_PSW+4
391
	l	%r12,__LC_THREAD_INFO	# load pointer to thread_info struct
Linus Torvalds's avatar
Linus Torvalds committed
392 393 394
	tm	SP_PSW+1(%r15),0x01	# forking a kernel thread ?
	bo	BASED(0f)
	st	%r15,SP_R15(%r15)	# store stack pointer for new kthread
Heiko Carstens's avatar
Heiko Carstens committed
395 396
0:	l	%r1,BASED(.Lschedtail)
	basr	%r14,%r1
397
	TRACE_IRQS_ON
Heiko Carstens's avatar
Heiko Carstens committed
398
	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
399
	b	BASED(sysc_tracenogo)
Linus Torvalds's avatar
Linus Torvalds committed
400 401

#
402 403
# kernel_execve function needs to deal with pt_regs that is not
# at the usual place
Linus Torvalds's avatar
Linus Torvalds committed
404
#
405
ENTRY(kernel_execve)
406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425
	stm	%r12,%r15,48(%r15)
	lr	%r14,%r15
	l	%r13,__LC_SVC_NEW_PSW+4
	s	%r15,BASED(.Lc_spsize)
	st	%r14,__SF_BACKCHAIN(%r15)
	la	%r12,SP_PTREGS(%r15)
	xc	0(__PT_SIZE,%r12),0(%r12)
	l	%r1,BASED(.Ldo_execve)
	lr	%r5,%r12
	basr	%r14,%r1
	ltr	%r2,%r2
	be	BASED(0f)
	a	%r15,BASED(.Lc_spsize)
	lm	%r12,%r15,48(%r15)
	br	%r14
	# execve succeeded.
0:	stnsm	__SF_EMPTY(%r15),0xfc	# disable interrupts
	l	%r15,__LC_KERNEL_STACK	# load ksp
	s	%r15,BASED(.Lc_spsize)	# make room for registers & psw
	mvc	SP_PTREGS(__PT_SIZE,%r15),0(%r12)	# copy pt_regs
426
	l	%r12,__LC_THREAD_INFO
427 428 429 430 431
	xc	__SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
	l	%r1,BASED(.Lexecve_tail)
	basr	%r14,%r1
	b	BASED(sysc_return)
Linus Torvalds's avatar
Linus Torvalds committed
432 433 434 435 436

/*
 * Program check handler routine
 */

437
ENTRY(pgm_check_handler)
Linus Torvalds's avatar
Linus Torvalds committed
438 439 440 441 442 443 444 445 446 447 448 449 450
/*
 * 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?).
 */
451
	stpt	__LC_SYNC_ENTER_TIMER
Linus Torvalds's avatar
Linus Torvalds committed
452
	SAVE_ALL_BASE __LC_SAVE_AREA
Heiko Carstens's avatar
Heiko Carstens committed
453 454
	tm	__LC_PGM_INT_CODE+1,0x80 # check whether we got a per exception
	bnz	BASED(pgm_per)		# got per exception -> special case
455 456 457 458 459
	SAVE_ALL_PGM __LC_PGM_OLD_PSW,__LC_SAVE_AREA
	CREATE_STACK_FRAME __LC_SAVE_AREA
	xc	SP_ILC(4,%r15),SP_ILC(%r15)
	mvc	SP_PSW(8,%r15),__LC_PGM_OLD_PSW
	l	%r12,__LC_THREAD_INFO	# load pointer to thread_info struct
Linus Torvalds's avatar
Linus Torvalds committed
460 461 462 463 464 465
	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
	bz	BASED(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:
Heiko Carstens's avatar
Heiko Carstens committed
466
	l	%r3,__LC_PGM_ILC	# load program interruption code
467 468
	l	%r4,__LC_TRANS_EXC_CODE
	REENABLE_IRQS
Linus Torvalds's avatar
Linus Torvalds committed
469 470
	la	%r8,0x7f
	nr	%r8,%r3
Heiko Carstens's avatar
Heiko Carstens committed
471
	sll	%r8,2
472 473
	l	%r1,BASED(.Ljump_table)
	l	%r1,0(%r8,%r1)		# load address of handler routine
Heiko Carstens's avatar
Heiko Carstens committed
474
	la	%r2,SP_PTREGS(%r15)	# address of register-save area
475
	basr	%r14,%r1		# branch to interrupt-handler
476 477
pgm_exit:
	b	BASED(sysc_return)
Linus Torvalds's avatar
Linus Torvalds committed
478 479 480 481 482

#
# handle per exception
#
pgm_per:
Heiko Carstens's avatar
Heiko Carstens committed
483 484
	tm	__LC_PGM_OLD_PSW,0x40	# test if per event recording is on
	bnz	BASED(pgm_per_std)	# ok, normal per event from user space
Linus Torvalds's avatar
Linus Torvalds committed
485
# ok its one of the special cases, now we need to find out which one
Heiko Carstens's avatar
Heiko Carstens committed
486 487
	clc	__LC_PGM_OLD_PSW(8),__LC_SVC_NEW_PSW
	be	BASED(pgm_svcper)
Linus Torvalds's avatar
Linus Torvalds committed
488
# no interesting special case, ignore PER event
Heiko Carstens's avatar
Heiko Carstens committed
489 490
	lm	%r12,%r15,__LC_SAVE_AREA
	lpsw	0x28
Linus Torvalds's avatar
Linus Torvalds committed
491 492 493 494 495

#
# Normal per exception
#
pgm_per_std:
496 497 498 499
	SAVE_ALL_PGM __LC_PGM_OLD_PSW,__LC_SAVE_AREA
	CREATE_STACK_FRAME __LC_SAVE_AREA
	mvc	SP_PSW(8,%r15),__LC_PGM_OLD_PSW
	l	%r12,__LC_THREAD_INFO	# load pointer to thread_info struct
Linus Torvalds's avatar
Linus Torvalds committed
500 501 502 503 504 505
	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
	bz	BASED(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:
506
	l	%r1,__TI_task(%r12)
507 508
	tm	SP_PSW+1(%r15),0x01	# kernel per event ?
	bz	BASED(kernel_per)
Martin Schwidefsky's avatar
Martin Schwidefsky committed
509 510 511 512
	mvc	__THREAD_per_cause(2,%r1),__LC_PER_CAUSE
	mvc	__THREAD_per_address(4,%r1),__LC_PER_ADDRESS
	mvc	__THREAD_per_paid(1,%r1),__LC_PER_PAID
	oi	__TI_flags+3(%r12),_TIF_PER_TRAP # set TIF_PER_TRAP
Heiko Carstens's avatar
Heiko Carstens committed
513
	l	%r3,__LC_PGM_ILC	# load program interruption code
514 515
	l	%r4,__LC_TRANS_EXC_CODE
	REENABLE_IRQS
Linus Torvalds's avatar
Linus Torvalds committed
516
	la	%r8,0x7f
Heiko Carstens's avatar
Heiko Carstens committed
517
	nr	%r8,%r3 		# clear per-event-bit and ilc
518 519
	be	BASED(pgm_exit2)	# only per or per+check ?
	sll	%r8,2
520 521
	l	%r1,BASED(.Ljump_table)
	l	%r1,0(%r8,%r1)		# load address of handler routine
522
	la	%r2,SP_PTREGS(%r15)	# address of register-save area
523
	basr	%r14,%r1		# branch to interrupt-handler
524 525
pgm_exit2:
	b	BASED(sysc_return)
Linus Torvalds's avatar
Linus Torvalds committed
526 527 528 529 530

#
# it was a single stepped SVC that is causing all the trouble
#
pgm_svcper:
531 532 533 534 535
	SAVE_ALL_PGM __LC_SVC_OLD_PSW,__LC_SAVE_AREA
	CREATE_STACK_FRAME __LC_SAVE_AREA
	mvc	SP_PSW(8,%r15),__LC_SVC_OLD_PSW
	mvc	SP_ILC(4,%r15),__LC_SVC_ILC
	l	%r12,__LC_THREAD_INFO	# load pointer to thread_info struct
Linus Torvalds's avatar
Linus Torvalds committed
536 537 538
	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
539
	l	%r8,__TI_task(%r12)
Martin Schwidefsky's avatar
Martin Schwidefsky committed
540 541 542 543
	mvc	__THREAD_per_cause(2,%r8),__LC_PER_CAUSE
	mvc	__THREAD_per_address(4,%r8),__LC_PER_ADDRESS
	mvc	__THREAD_per_paid(1,%r8),__LC_PER_PAID
	oi	__TI_flags+3(%r12),_TIF_PER_TRAP # set TIF_PER_TRAP
Linus Torvalds's avatar
Linus Torvalds committed
544
	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
545
	lm	%r2,%r6,SP_R2(%r15)	# load svc arguments
Linus Torvalds's avatar
Linus Torvalds committed
546 547
	b	BASED(sysc_do_svc)

Michael Grundy's avatar
Michael Grundy committed
548 549 550 551
#
# per was called from kernel, must be kprobes
#
kernel_per:
552
	REENABLE_IRQS
553
	xc	SP_SVCNR(2,%r15),SP_SVCNR(%r15)
Michael Grundy's avatar
Michael Grundy committed
554 555
	la	%r2,SP_PTREGS(%r15)	# address of register-save area
	l	%r1,BASED(.Lhandle_per)	# load adr. of per handler
556 557
	basr	%r14,%r1		# branch to do_single_step
	b	BASED(pgm_exit)
Michael Grundy's avatar
Michael Grundy committed
558

Linus Torvalds's avatar
Linus Torvalds committed
559 560 561 562
/*
 * IO interrupt handler routine
 */

563
ENTRY(io_int_handler)
Linus Torvalds's avatar
Linus Torvalds committed
564
	stck	__LC_INT_CLOCK
565
	stpt	__LC_ASYNC_ENTER_TIMER
566
	SAVE_ALL_ASYNC __LC_IO_OLD_PSW,__LC_SAVE_AREA+16
567 568 569
	CREATE_STACK_FRAME __LC_SAVE_AREA+16
	mvc	SP_PSW(8,%r15),0(%r12)	# move user PSW to stack
	l	%r12,__LC_THREAD_INFO	# load pointer to thread_info struct
Linus Torvalds's avatar
Linus Torvalds committed
570 571 572 573 574 575
	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
	bz	BASED(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:
576
	TRACE_IRQS_OFF
Heiko Carstens's avatar
Heiko Carstens committed
577 578 579
	l	%r1,BASED(.Ldo_IRQ)	# load address of do_IRQ
	la	%r2,SP_PTREGS(%r15)	# address of register-save area
	basr	%r14,%r1		# branch to standard irq handler
Linus Torvalds's avatar
Linus Torvalds committed
580
io_return:
581 582 583
	LOCKDEP_SYS_EXIT
	TRACE_IRQS_ON
io_tif:
584
	tm	__TI_flags+3(%r12),_TIF_WORK_INT
Heiko Carstens's avatar
Heiko Carstens committed
585
	bnz	BASED(io_work)		# there is work to do (signals etc.)
586
io_restore:
Heiko Carstens's avatar
Heiko Carstens committed
587
	RESTORE_ALL __LC_RETURN_PSW,0
588
io_done:
Linus Torvalds's avatar
Linus Torvalds committed
589

590
#
591 592 593 594 595
# 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 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.
596 597 598
#
io_work:
	tm	SP_PSW+1(%r15),0x01	# returning to user ?
599 600
	bo	BASED(io_work_user)	# yes -> do resched & signal
#ifdef CONFIG_PREEMPT
601
	# check for preemptive scheduling
602
	icm	%r0,15,__TI_precount(%r12)
603
	bnz	BASED(io_restore)	# preemption disabled
604
	tm	__TI_flags+3(%r12),_TIF_NEED_RESCHED
605
	bno	BASED(io_restore)
606
	# switch to kernel stack
Linus Torvalds's avatar
Linus Torvalds committed
607 608 609
	l	%r1,SP_R15(%r15)
	s	%r1,BASED(.Lc_spsize)
	mvc	SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
Heiko Carstens's avatar
Heiko Carstens committed
610
	xc	__SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain
Linus Torvalds's avatar
Linus Torvalds committed
611
	lr	%r15,%r1
612 613 614
	# TRACE_IRQS_ON already done at io_return, call
	# TRACE_IRQS_OFF to keep things symmetrical
	TRACE_IRQS_OFF
Heiko Carstens's avatar
Heiko Carstens committed
615
	l	%r1,BASED(.Lpreempt_schedule_irq)
616 617 618
	basr	%r14,%r1		# call preempt_schedule_irq
	b	BASED(io_return)
#else
619
	b	BASED(io_restore)
620
#endif
Linus Torvalds's avatar
Linus Torvalds committed
621

622 623 624
#
# Need to do work before returning to userspace, switch to kernel stack
#
625
io_work_user:
Linus Torvalds's avatar
Linus Torvalds committed
626 627 628
	l	%r1,__LC_KERNEL_STACK
	s	%r1,BASED(.Lc_spsize)
	mvc	SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
Heiko Carstens's avatar
Heiko Carstens committed
629
	xc	__SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain
Linus Torvalds's avatar
Linus Torvalds committed
630
	lr	%r15,%r1
631

Linus Torvalds's avatar
Linus Torvalds committed
632 633
#
# One of the work bits is on. Find out which one.
634
# Checked are: _TIF_SIGPENDING, _TIF_NOTIFY_RESUME, _TIF_NEED_RESCHED
Heiko Carstens's avatar
Heiko Carstens committed
635
#		and _TIF_MCCK_PENDING
Linus Torvalds's avatar
Linus Torvalds committed
636
#
637
io_work_tif:
638
	tm	__TI_flags+3(%r12),_TIF_MCCK_PENDING
Heiko Carstens's avatar
Heiko Carstens committed
639
	bo	BASED(io_mcck_pending)
640
	tm	__TI_flags+3(%r12),_TIF_NEED_RESCHED
Linus Torvalds's avatar
Linus Torvalds committed
641
	bo	BASED(io_reschedule)
642
	tm	__TI_flags+3(%r12),_TIF_SIGPENDING
643
	bo	BASED(io_sigpending)
644
	tm	__TI_flags+3(%r12),_TIF_NOTIFY_RESUME
645 646
	bo	BASED(io_notify_resume)
	b	BASED(io_return)	# beware of critical section cleanup
Linus Torvalds's avatar
Linus Torvalds committed
647

648 649 650 651
#
# _TIF_MCCK_PENDING is set, call handler
#
io_mcck_pending:
652
	# TRACE_IRQS_ON already done at io_return
653
	l	%r1,BASED(.Ls390_handle_mcck)
Heiko Carstens's avatar
Heiko Carstens committed
654
	basr	%r14,%r1		# TIF bit will be cleared by handler
655 656
	TRACE_IRQS_OFF
	b	BASED(io_return)
657

Linus Torvalds's avatar
Linus Torvalds committed
658 659
#
# _TIF_NEED_RESCHED is set, call schedule
Heiko Carstens's avatar
Heiko Carstens committed
660 661
#
io_reschedule:
662
	# TRACE_IRQS_ON already done at io_return
Heiko Carstens's avatar
Heiko Carstens committed
663 664 665 666
	l	%r1,BASED(.Lschedule)
	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
	basr	%r14,%r1		# call scheduler
	stnsm	__SF_EMPTY(%r15),0xfc	# disable I/O and ext. interrupts
667
	TRACE_IRQS_OFF
668
	b	BASED(io_return)
Linus Torvalds's avatar
Linus Torvalds committed
669 670

#
671
# _TIF_SIGPENDING is set, call do_signal
Linus Torvalds's avatar
Linus Torvalds committed
672
#
Heiko Carstens's avatar
Heiko Carstens committed
673
io_sigpending:
674
	# TRACE_IRQS_ON already done at io_return
Heiko Carstens's avatar
Heiko Carstens committed
675 676 677 678 679
	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
	l	%r1,BASED(.Ldo_signal)
	basr	%r14,%r1		# call do_signal
	stnsm	__SF_EMPTY(%r15),0xfc	# disable I/O and ext. interrupts
680
	TRACE_IRQS_OFF
681
	b	BASED(io_return)
Linus Torvalds's avatar
Linus Torvalds committed
682

Martin Schwidefsky's avatar
Martin Schwidefsky committed
683 684 685 686
#
# _TIF_SIGPENDING is set, call do_signal
#
io_notify_resume:
687
	# TRACE_IRQS_ON already done at io_return
Martin Schwidefsky's avatar
Martin Schwidefsky committed
688 689 690 691 692 693
	stosm	__SF_EMPTY(%r15),0x03	# reenable interrupts
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
	l	%r1,BASED(.Ldo_notify_resume)
	basr	%r14,%r1		# call do_signal
	stnsm	__SF_EMPTY(%r15),0xfc	# disable I/O and ext. interrupts
	TRACE_IRQS_OFF
694
	b	BASED(io_return)
Martin Schwidefsky's avatar
Martin Schwidefsky committed
695

Linus Torvalds's avatar
Linus Torvalds committed
696 697 698 699
/*
 * External interrupt handler routine
 */

700
ENTRY(ext_int_handler)
Linus Torvalds's avatar
Linus Torvalds committed
701
	stck	__LC_INT_CLOCK
702
	stpt	__LC_ASYNC_ENTER_TIMER
703
	SAVE_ALL_ASYNC __LC_EXT_OLD_PSW,__LC_SAVE_AREA+16
704 705 706
	CREATE_STACK_FRAME __LC_SAVE_AREA+16
	mvc	SP_PSW(8,%r15),0(%r12)	# move user PSW to stack
	l	%r12,__LC_THREAD_INFO	# load pointer to thread_info struct
Linus Torvalds's avatar
Linus Torvalds committed
707 708 709 710 711 712
	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
	bz	BASED(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:
713
	TRACE_IRQS_OFF
Heiko Carstens's avatar
Heiko Carstens committed
714
	la	%r2,SP_PTREGS(%r15)	# address of register-save area
715 716
	l	%r3,__LC_CPU_ADDRESS	# get cpu address + interruption code
	l	%r4,__LC_EXT_PARAMS	# get external parameters
Linus Torvalds's avatar
Linus Torvalds committed
717 718 719 720
	l	%r1,BASED(.Ldo_extint)
	basr	%r14,%r1
	b	BASED(io_return)

721 722
__critical_end:

Linus Torvalds's avatar
Linus Torvalds committed
723 724 725 726
/*
 * Machine check handler routines
 */

727
ENTRY(mcck_int_handler)
728
	stck	__LC_MCCK_CLOCK
729 730
	spt	__LC_CPU_TIMER_SAVE_AREA	# revalidate cpu timer
	lm	%r0,%r15,__LC_GPREGS_SAVE_AREA	# revalidate gprs
Linus Torvalds's avatar
Linus Torvalds committed
731
	SAVE_ALL_BASE __LC_SAVE_AREA+32
732
	la	%r12,__LC_MCK_OLD_PSW
Heiko Carstens's avatar
Heiko Carstens committed
733
	tm	__LC_MCCK_CODE,0x80	# system damage?
734
	bo	BASED(mcck_int_main)	# yes -> rest of mcck code invalid
735
	mvc	__LC_MCCK_ENTER_TIMER(8),__LC_CPU_TIMER_SAVE_AREA
736 737 738 739 740 741 742 743 744 745 746 747 748
	tm	__LC_MCCK_CODE+5,0x02	# stored cpu timer value valid?
	bo	BASED(1f)
	la	%r14,__LC_SYNC_ENTER_TIMER
	clc	0(8,%r14),__LC_ASYNC_ENTER_TIMER
	bl	BASED(0f)
	la	%r14,__LC_ASYNC_ENTER_TIMER
0:	clc	0(8,%r14),__LC_EXIT_TIMER
	bl	BASED(0f)
	la	%r14,__LC_EXIT_TIMER
0:	clc	0(8,%r14),__LC_LAST_UPDATE_TIMER
	bl	BASED(0f)
	la	%r14,__LC_LAST_UPDATE_TIMER
0:	spt	0(%r14)
749
	mvc	__LC_MCCK_ENTER_TIMER(8),0(%r14)
750
1:	tm	__LC_MCCK_CODE+2,0x09	# mwp + ia of old psw valid?
751 752 753 754 755 756 757 758 759 760 761 762 763 764 765
	bno	BASED(mcck_int_main)	# no -> skip cleanup critical
	tm	__LC_MCK_OLD_PSW+1,0x01	# test problem state bit
	bnz	BASED(mcck_int_main)	# from user -> load async stack
	clc	__LC_MCK_OLD_PSW+4(4),BASED(.Lcritical_end)
	bhe	BASED(mcck_int_main)
	clc	__LC_MCK_OLD_PSW+4(4),BASED(.Lcritical_start)
	bl	BASED(mcck_int_main)
	l	%r14,BASED(.Lcleanup_critical)
	basr	%r14,%r14
mcck_int_main:
	l	%r14,__LC_PANIC_STACK	# are we already on the panic stack?
	slr	%r14,%r15
	sra	%r14,PAGE_SHIFT
	be	BASED(0f)
	l	%r15,__LC_PANIC_STACK	# load panic stack
766 767 768 769
0:	s	%r15,BASED(.Lc_spsize)	# make room for registers & psw
	CREATE_STACK_FRAME __LC_SAVE_AREA+32
	mvc	SP_PSW(8,%r15),0(%r12)
	l	%r12,__LC_THREAD_INFO	# load pointer to thread_info struct
Heiko Carstens's avatar
Heiko Carstens committed
770
	tm	__LC_MCCK_CODE+2,0x08	# mwp of old psw valid?
771
	bno	BASED(mcck_no_vtime)	# no -> skip cleanup critical
772
	tm	SP_PSW+1(%r15),0x01	# interrupting from user ?
773
	bz	BASED(mcck_no_vtime)
774
	UPDATE_VTIME __LC_EXIT_TIMER,__LC_MCCK_ENTER_TIMER,__LC_USER_TIMER
775
	UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
776
	mvc	__LC_LAST_UPDATE_TIMER(8),__LC_MCCK_ENTER_TIMER
777
mcck_no_vtime:
778
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
Heiko Carstens's avatar
Heiko Carstens committed
779 780 781
	l	%r1,BASED(.Ls390_mcck)
	basr	%r14,%r1		# call machine check handler
	tm	SP_PSW+1(%r15),0x01	# returning to user ?
782
	bno	BASED(mcck_return)
Heiko Carstens's avatar
Heiko Carstens committed
783
	l	%r1,__LC_KERNEL_STACK	# switch to kernel stack
784 785
	s	%r1,BASED(.Lc_spsize)
	mvc	SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
Heiko Carstens's avatar
Heiko Carstens committed
786
	xc	__SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain
787 788
	lr	%r15,%r1
	stosm	__SF_EMPTY(%r15),0x04	# turn dat on
789
	tm	__TI_flags+3(%r12),_TIF_MCCK_PENDING
790
	bno	BASED(mcck_return)
791
	TRACE_IRQS_OFF
792 793
	l	%r1,BASED(.Ls390_handle_mcck)
	basr	%r14,%r1		# call machine check handler
794
	TRACE_IRQS_ON
Linus Torvalds's avatar
Linus Torvalds committed
795
mcck_return:
796 797 798 799 800 801 802
	mvc	__LC_RETURN_MCCK_PSW(8),SP_PSW(%r15) # move return PSW
	ni	__LC_RETURN_MCCK_PSW+1,0xfd # clear wait state bit
	tm	__LC_RETURN_MCCK_PSW+1,0x01 # returning to user ?
	bno	BASED(0f)
	lm	%r0,%r15,SP_R0(%r15)	# load gprs 0-15
	stpt	__LC_EXIT_TIMER
	lpsw	__LC_RETURN_MCCK_PSW	# back to caller
803
0:	lm	%r0,%r15,SP_R0(%r15)	# load gprs 0-15
804 805
	lpsw	__LC_RETURN_MCCK_PSW	# back to caller

Heiko Carstens's avatar
Heiko Carstens committed
806
	RESTORE_ALL __LC_RETURN_MCCK_PSW,0
Linus Torvalds's avatar
Linus Torvalds committed
807 808 809 810

/*
 * Restart interruption handler, kick starter for additional CPUs
 */
811
#ifdef CONFIG_SMP
812
	__CPUINIT
813
ENTRY(restart_int_handler)
814 815 816 817 818 819
	basr	%r1,0
restart_base:
	spt	restart_vtime-restart_base(%r1)
	stck	__LC_LAST_UPDATE_CLOCK
	mvc	__LC_LAST_UPDATE_TIMER(8),restart_vtime-restart_base(%r1)
	mvc	__LC_EXIT_TIMER(8),restart_vtime-restart_base(%r1)
Heiko Carstens's avatar
Heiko Carstens committed
820 821 822 823
	l	%r15,__LC_SAVE_AREA+60	# load ksp
	lctl	%c0,%c15,__LC_CREGS_SAVE_AREA # get new ctl regs
	lam	%a0,%a15,__LC_AREGS_SAVE_AREA
	lm	%r6,%r15,__SF_GPRS(%r15) # load registers from clone
824 825 826 827
	l	%r1,__LC_THREAD_INFO
	mvc	__LC_USER_TIMER(8),__TI_user_timer(%r1)
	mvc	__LC_SYSTEM_TIMER(8),__TI_system_timer(%r1)
	xc	__LC_STEAL_TIMER(8),__LC_STEAL_TIMER
Heiko Carstens's avatar
Heiko Carstens committed
828 829 830
	stosm	__SF_EMPTY(%r15),0x04	# now we can turn dat on
	basr	%r14,0
	l	%r14,restart_addr-.(%r14)
831
	basr	%r14,%r14		# branch to start_secondary
Linus Torvalds's avatar
Linus Torvalds committed
832
restart_addr:
Heiko Carstens's avatar
Heiko Carstens committed
833
	.long	start_secondary
834 835 836
	.align	8
restart_vtime:
	.long	0x7fffffff,0xffffffff
837
	.previous
Linus Torvalds's avatar
Linus Torvalds committed
838 839 840 841
#else
/*
 * If we do not run with SMP enabled, let the new CPU crash ...
 */
842
ENTRY(restart_int_handler)
Heiko Carstens's avatar
Heiko Carstens committed
843
	basr	%r1,0
Linus Torvalds's avatar
Linus Torvalds committed
844
restart_base:
Heiko Carstens's avatar
Heiko Carstens committed
845 846
	lpsw	restart_crash-restart_base(%r1)
	.align	8
Linus Torvalds's avatar
Linus Torvalds committed
847
restart_crash:
Heiko Carstens's avatar
Heiko Carstens committed
848
	.long	0x000a0000,0x00000000
Linus Torvalds's avatar
Linus Torvalds committed
849 850 851
restart_go:
#endif

852 853
	.section .kprobes.text, "ax"

Linus Torvalds's avatar
Linus Torvalds committed
854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871
#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:
	l	%r15,__LC_PANIC_STACK	# change to panic stack
	sl	%r15,BASED(.Lc_spsize)
	mvc	SP_PSW(8,%r15),0(%r12)	# move user PSW to stack
	stm	%r0,%r11,SP_R0(%r15)	# store gprs %r0-%r11 to kernel stack
	la	%r1,__LC_SAVE_AREA
	ch	%r12,BASED(.L0x020)	# old psw addr == __LC_SVC_OLD_PSW ?
	be	BASED(0f)
	ch	%r12,BASED(.L0x028)	# old psw addr == __LC_PGM_OLD_PSW ?
	be	BASED(0f)
	la	%r1,__LC_SAVE_AREA+16
0:	mvc	SP_R12(16,%r15),0(%r1)	# move %r12-%r15 to stack
Heiko Carstens's avatar
Heiko Carstens committed
872
	xc	__SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) # clear back chain
Linus Torvalds's avatar
Linus Torvalds committed
873
	l	%r1,BASED(1f)		# branch to kernel_stack_overflow
Heiko Carstens's avatar
Heiko Carstens committed
874
	la	%r2,SP_PTREGS(%r15)	# load pt_regs
Linus Torvalds's avatar
Linus Torvalds committed
875
	br	%r1
Heiko Carstens's avatar
Heiko Carstens committed
876
1:	.long	kernel_stack_overflow
Linus Torvalds's avatar
Linus Torvalds committed
877 878 879 880
#endif

cleanup_table_system_call:
	.long	system_call + 0x80000000, sysc_do_svc + 0x80000000
881 882 883 884 885 886 887 888
cleanup_table_sysc_tif:
	.long	sysc_tif + 0x80000000, sysc_restore + 0x80000000
cleanup_table_sysc_restore:
	.long	sysc_restore + 0x80000000, sysc_done + 0x80000000
cleanup_table_io_tif:
	.long	io_tif + 0x80000000, io_restore + 0x80000000
cleanup_table_io_restore:
	.long	io_restore + 0x80000000, io_done + 0x80000000
Linus Torvalds's avatar
Linus Torvalds committed
889 890 891 892 893 894 895

cleanup_critical:
	clc	4(4,%r12),BASED(cleanup_table_system_call)
	bl	BASED(0f)
	clc	4(4,%r12),BASED(cleanup_table_system_call+4)
	bl	BASED(cleanup_system_call)
0:
896
	clc	4(4,%r12),BASED(cleanup_table_sysc_tif)
Linus Torvalds's avatar
Linus Torvalds committed
897
	bl	BASED(0f)
898 899
	clc	4(4,%r12),BASED(cleanup_table_sysc_tif+4)
	bl	BASED(cleanup_sysc_tif)
Linus Torvalds's avatar
Linus Torvalds committed
900
0:
901
	clc	4(4,%r12),BASED(cleanup_table_sysc_restore)
Linus Torvalds's avatar
Linus Torvalds committed
902
	bl	BASED(0f)
903 904
	clc	4(4,%r12),BASED(cleanup_table_sysc_restore+4)
	bl	BASED(cleanup_sysc_restore)
905
0:
906
	clc	4(4,%r12),BASED(cleanup_table_io_tif)
907
	bl	BASED(0f)
908 909
	clc	4(4,%r12),BASED(cleanup_table_io_tif+4)
	bl	BASED(cleanup_io_tif)
910
0:
911
	clc	4(4,%r12),BASED(cleanup_table_io_restore)
912
	bl	BASED(0f)
913 914
	clc	4(4,%r12),BASED(cleanup_table_io_restore+4)
	bl	BASED(cleanup_io_restore)