| blob | 0dc2b6d0a1ec8557f7450d5fbd255d2758bf8512 |
1 /*
2 * S390 low-level entry points.
3 *
4 * Copyright IBM Corp. 1999, 2012
5 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
6 * Hartmut Penner (hp@de.ibm.com),
7 * Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
8 * Heiko Carstens <heiko.carstens@de.ibm.com>
9 */
11 #include <linux/init.h>
12 #include <linux/linkage.h>
13 #include <asm/cache.h>
14 #include <asm/errno.h>
15 #include <asm/ptrace.h>
16 #include <asm/thread_info.h>
17 #include <asm/asm-offsets.h>
18 #include <asm/unistd.h>
19 #include <asm/page.h>
20 #include <asm/sigp.h>
21 #include <asm/irq.h>
23 __PT_R0 = __PT_GPRS
24 __PT_R1 = __PT_GPRS + 4
25 __PT_R2 = __PT_GPRS + 8
26 __PT_R3 = __PT_GPRS + 12
27 __PT_R4 = __PT_GPRS + 16
28 __PT_R5 = __PT_GPRS + 20
29 __PT_R6 = __PT_GPRS + 24
30 __PT_R7 = __PT_GPRS + 28
31 __PT_R8 = __PT_GPRS + 32
32 __PT_R9 = __PT_GPRS + 36
33 __PT_R10 = __PT_GPRS + 40
34 __PT_R11 = __PT_GPRS + 44
35 __PT_R12 = __PT_GPRS + 48
36 __PT_R13 = __PT_GPRS + 524
37 __PT_R14 = __PT_GPRS + 56
38 __PT_R15 = __PT_GPRS + 60
40 _TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
41 _TIF_MCCK_PENDING | _TIF_PER_TRAP )
42 _TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
43 _TIF_MCCK_PENDING)
44 _TIF_TRACE = (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | \
45 _TIF_SYSCALL_TRACEPOINT)
47 STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
48 STACK_SIZE = 1 << STACK_SHIFT
49 STACK_INIT = STACK_SIZE - STACK_FRAME_OVERHEAD - __PT_SIZE
51 #define BASED(name) name-system_call(%r13)
53 .macro TRACE_IRQS_ON
54 #ifdef CONFIG_TRACE_IRQFLAGS
55 basr %r2,%r0
56 l %r1,BASED(.Lhardirqs_on)
57 basr %r14,%r1 # call trace_hardirqs_on_caller
58 #endif
59 .endm
61 .macro TRACE_IRQS_OFF
62 #ifdef CONFIG_TRACE_IRQFLAGS
63 basr %r2,%r0
64 l %r1,BASED(.Lhardirqs_off)
65 basr %r14,%r1 # call trace_hardirqs_off_caller
66 #endif
67 .endm
69 .macro LOCKDEP_SYS_EXIT
70 #ifdef CONFIG_LOCKDEP
71 tm __PT_PSW+1(%r11),0x01 # returning to user ?
72 jz .+10
73 l %r1,BASED(.Llockdep_sys_exit)
74 basr %r14,%r1 # call lockdep_sys_exit
75 #endif
76 .endm
78 .macro CHECK_STACK stacksize,savearea
79 #ifdef CONFIG_CHECK_STACK
80 tml %r15,\stacksize - CONFIG_STACK_GUARD
81 la %r14,\savearea
82 jz stack_overflow
83 #endif
84 .endm
86 .macro SWITCH_ASYNC savearea,stack,shift
87 tmh %r8,0x0001 # interrupting from user ?
88 jnz 1f
89 lr %r14,%r9
90 sl %r14,BASED(.Lcritical_start)
91 cl %r14,BASED(.Lcritical_length)
92 jhe 0f
93 la %r11,\savearea # inside critical section, do cleanup
94 bras %r14,cleanup_critical
95 tmh %r8,0x0001 # retest problem state after cleanup
96 jnz 1f
97 0: l %r14,\stack # are we already on the target stack?
98 slr %r14,%r15
99 sra %r14,\shift
100 jnz 1f
101 CHECK_STACK 1<<\shift,\savearea
102 ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
103 j 2f
104 1: l %r15,\stack # load target stack
105 2: la %r11,STACK_FRAME_OVERHEAD(%r15)
106 .endm
108 .macro ADD64 high,low,timer
109 al \high,\timer
110 al \low,4+\timer
111 brc 12,.+8
112 ahi \high,1
113 .endm
115 .macro SUB64 high,low,timer
116 sl \high,\timer
117 sl \low,4+\timer
118 brc 3,.+8
119 ahi \high,-1
120 .endm
122 .macro UPDATE_VTIME high,low,enter_timer
123 lm \high,\low,__LC_EXIT_TIMER
124 SUB64 \high,\low,\enter_timer
125 ADD64 \high,\low,__LC_USER_TIMER
126 stm \high,\low,__LC_USER_TIMER
127 lm \high,\low,__LC_LAST_UPDATE_TIMER
128 SUB64 \high,\low,__LC_EXIT_TIMER
129 ADD64 \high,\low,__LC_SYSTEM_TIMER
130 stm \high,\low,__LC_SYSTEM_TIMER
131 mvc __LC_LAST_UPDATE_TIMER(8),\enter_timer
132 .endm
134 .macro REENABLE_IRQS
135 st %r8,__LC_RETURN_PSW
136 ni __LC_RETURN_PSW,0xbf
137 ssm __LC_RETURN_PSW
138 .endm
140 .section .kprobes.text, "ax"
142 /*
143 * Scheduler resume function, called by switch_to
144 * gpr2 = (task_struct *) prev
145 * gpr3 = (task_struct *) next
146 * Returns:
147 * gpr2 = prev
148 */
149 ENTRY(__switch_to)
150 stm %r6,%r15,__SF_GPRS(%r15) # store gprs of prev task
151 st %r15,__THREAD_ksp(%r2) # store kernel stack of prev
152 l %r4,__THREAD_info(%r2) # get thread_info of prev
153 l %r5,__THREAD_info(%r3) # get thread_info of next
154 lr %r15,%r5
155 ahi %r15,STACK_INIT # end of kernel stack of next
156 st %r3,__LC_CURRENT # store task struct of next
157 st %r5,__LC_THREAD_INFO # store thread info of next
158 st %r15,__LC_KERNEL_STACK # store end of kernel stack
159 lctl %c4,%c4,__TASK_pid(%r3) # load pid to control reg. 4
160 mvc __LC_CURRENT_PID(4,%r0),__TASK_pid(%r3) # store pid of next
161 l %r15,__THREAD_ksp(%r3) # load kernel stack of next
162 tm __TI_flags+3(%r4),_TIF_MCCK_PENDING # machine check pending?
163 jz 0f
164 ni __TI_flags+3(%r4),255-_TIF_MCCK_PENDING # clear flag in prev
165 oi __TI_flags+3(%r5),_TIF_MCCK_PENDING # set it in next
166 0: lm %r6,%r15,__SF_GPRS(%r15) # load gprs of next task
167 br %r14
169 __critical_start:
170 /*
171 * SVC interrupt handler routine. System calls are synchronous events and
172 * are executed with interrupts enabled.
173 */
175 ENTRY(system_call)
176 stpt __LC_SYNC_ENTER_TIMER
177 sysc_stm:
178 stm %r8,%r15,__LC_SAVE_AREA_SYNC
179 l %r12,__LC_THREAD_INFO
180 l %r13,__LC_SVC_NEW_PSW+4
181 sysc_per:
182 l %r15,__LC_KERNEL_STACK
183 la %r11,STACK_FRAME_OVERHEAD(%r15) # pointer to pt_regs
184 sysc_vtime:
185 UPDATE_VTIME %r8,%r9,__LC_SYNC_ENTER_TIMER
186 stm %r0,%r7,__PT_R0(%r11)
187 mvc __PT_R8(32,%r11),__LC_SAVE_AREA_SYNC
188 mvc __PT_PSW(8,%r11),__LC_SVC_OLD_PSW
189 mvc __PT_INT_CODE(4,%r11),__LC_SVC_ILC
190 sysc_do_svc:
191 oi __TI_flags+3(%r12),_TIF_SYSCALL
192 l %r10,__TI_sysc_table(%r12) # 31 bit system call table
193 lh %r8,__PT_INT_CODE+2(%r11)
194 sla %r8,2 # shift and test for svc0
195 jnz sysc_nr_ok
196 # svc 0: system call number in %r1
197 cl %r1,BASED(.Lnr_syscalls)
198 jnl sysc_nr_ok
199 sth %r1,__PT_INT_CODE+2(%r11)
200 lr %r8,%r1
201 sla %r8,2
202 sysc_nr_ok:
203 xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
204 st %r2,__PT_ORIG_GPR2(%r11)
205 st %r7,STACK_FRAME_OVERHEAD(%r15)
206 l %r9,0(%r8,%r10) # get system call addr.
207 tm __TI_flags+2(%r12),_TIF_TRACE >> 8
208 jnz sysc_tracesys
209 basr %r14,%r9 # call sys_xxxx
210 st %r2,__PT_R2(%r11) # store return value
212 sysc_return:
213 LOCKDEP_SYS_EXIT
214 sysc_tif:
215 tm __PT_PSW+1(%r11),0x01 # returning to user ?
216 jno sysc_restore
217 tm __TI_flags+3(%r12),_TIF_WORK_SVC
218 jnz sysc_work # check for work
219 ni __TI_flags+3(%r12),255-_TIF_SYSCALL
220 sysc_restore:
221 mvc __LC_RETURN_PSW(8),__PT_PSW(%r11)
222 stpt __LC_EXIT_TIMER
223 lm %r0,%r15,__PT_R0(%r11)
224 lpsw __LC_RETURN_PSW
225 sysc_done:
227 #
228 # One of the work bits is on. Find out which one.
229 #
230 sysc_work:
231 tm __TI_flags+3(%r12),_TIF_MCCK_PENDING
232 jo sysc_mcck_pending
233 tm __TI_flags+3(%r12),_TIF_NEED_RESCHED
234 jo sysc_reschedule
235 tm __TI_flags+3(%r12),_TIF_PER_TRAP
236 jo sysc_singlestep
237 tm __TI_flags+3(%r12),_TIF_SIGPENDING
238 jo sysc_sigpending
239 tm __TI_flags+3(%r12),_TIF_NOTIFY_RESUME
240 jo sysc_notify_resume
241 j sysc_return # beware of critical section cleanup
243 #
244 # _TIF_NEED_RESCHED is set, call schedule
245 #
246 sysc_reschedule:
247 l %r1,BASED(.Lschedule)
248 la %r14,BASED(sysc_return)
249 br %r1 # call schedule
251 #
252 # _TIF_MCCK_PENDING is set, call handler
253 #
254 sysc_mcck_pending:
255 l %r1,BASED(.Lhandle_mcck)
256 la %r14,BASED(sysc_return)
257 br %r1 # TIF bit will be cleared by handler
259 #
260 # _TIF_SIGPENDING is set, call do_signal
261 #
262 sysc_sigpending:
263 lr %r2,%r11 # pass pointer to pt_regs
264 l %r1,BASED(.Ldo_signal)
265 basr %r14,%r1 # call do_signal
266 tm __TI_flags+3(%r12),_TIF_SYSCALL
267 jno sysc_return
268 lm %r2,%r7,__PT_R2(%r11) # load svc arguments
269 l %r10,__TI_sysc_table(%r12) # 31 bit system call table
270 xr %r8,%r8 # svc 0 returns -ENOSYS
271 clc __PT_INT_CODE+2(2,%r11),BASED(.Lnr_syscalls+2)
272 jnl sysc_nr_ok # invalid svc number -> do svc 0
273 lh %r8,__PT_INT_CODE+2(%r11) # load new svc number
274 sla %r8,2
275 j sysc_nr_ok # restart svc
277 #
278 # _TIF_NOTIFY_RESUME is set, call do_notify_resume
279 #
280 sysc_notify_resume:
281 lr %r2,%r11 # pass pointer to pt_regs
282 l %r1,BASED(.Ldo_notify_resume)
283 la %r14,BASED(sysc_return)
284 br %r1 # call do_notify_resume
286 #
287 # _TIF_PER_TRAP is set, call do_per_trap
288 #
289 sysc_singlestep:
290 ni __TI_flags+3(%r12),255-_TIF_PER_TRAP
291 lr %r2,%r11 # pass pointer to pt_regs
292 l %r1,BASED(.Ldo_per_trap)
293 la %r14,BASED(sysc_return)
294 br %r1 # call do_per_trap
296 #
297 # call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
298 # and after the system call
299 #
300 sysc_tracesys:
301 l %r1,BASED(.Ltrace_enter)
302 lr %r2,%r11 # pass pointer to pt_regs
303 la %r3,0
304 xr %r0,%r0
305 icm %r0,3,__PT_INT_CODE+2(%r11)
306 st %r0,__PT_R2(%r11)
307 basr %r14,%r1 # call do_syscall_trace_enter
308 cl %r2,BASED(.Lnr_syscalls)
309 jnl sysc_tracenogo
310 lr %r8,%r2
311 sll %r8,2
312 l %r9,0(%r8,%r10)
313 sysc_tracego:
314 lm %r3,%r7,__PT_R3(%r11)
315 st %r7,STACK_FRAME_OVERHEAD(%r15)
316 l %r2,__PT_ORIG_GPR2(%r11)
317 basr %r14,%r9 # call sys_xxx
318 st %r2,__PT_R2(%r11) # store return value
319 sysc_tracenogo:
320 tm __TI_flags+2(%r12),_TIF_TRACE >> 8
321 jz sysc_return
322 l %r1,BASED(.Ltrace_exit)
323 lr %r2,%r11 # pass pointer to pt_regs
324 la %r14,BASED(sysc_return)
325 br %r1 # call do_syscall_trace_exit
327 #
328 # a new process exits the kernel with ret_from_fork
329 #
330 ENTRY(ret_from_fork)
331 la %r11,STACK_FRAME_OVERHEAD(%r15)
332 l %r12,__LC_THREAD_INFO
333 l %r13,__LC_SVC_NEW_PSW+4
334 l %r1,BASED(.Lschedule_tail)
335 basr %r14,%r1 # call schedule_tail
336 TRACE_IRQS_ON
337 ssm __LC_SVC_NEW_PSW # reenable interrupts
338 tm __PT_PSW+1(%r11),0x01 # forking a kernel thread ?
339 jne sysc_tracenogo
340 # it's a kernel thread
341 lm %r9,%r10,__PT_R9(%r11) # load gprs
342 ENTRY(kernel_thread_starter)
343 la %r2,0(%r10)
344 basr %r14,%r9
345 j sysc_tracenogo
347 /*
348 * Program check handler routine
349 */
351 ENTRY(pgm_check_handler)
352 stpt __LC_SYNC_ENTER_TIMER
353 stm %r8,%r15,__LC_SAVE_AREA_SYNC
354 l %r12,__LC_THREAD_INFO
355 l %r13,__LC_SVC_NEW_PSW+4
356 lm %r8,%r9,__LC_PGM_OLD_PSW
357 tmh %r8,0x0001 # test problem state bit
358 jnz 1f # -> fault in user space
359 tmh %r8,0x4000 # PER bit set in old PSW ?
360 jnz 0f # -> enabled, can't be a double fault
361 tm __LC_PGM_ILC+3,0x80 # check for per exception
362 jnz pgm_svcper # -> single stepped svc
363 0: CHECK_STACK STACK_SIZE,__LC_SAVE_AREA_SYNC
364 ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
365 j 2f
366 1: UPDATE_VTIME %r14,%r15,__LC_SYNC_ENTER_TIMER
367 l %r15,__LC_KERNEL_STACK
368 2: la %r11,STACK_FRAME_OVERHEAD(%r15)
369 stm %r0,%r7,__PT_R0(%r11)
370 mvc __PT_R8(32,%r11),__LC_SAVE_AREA_SYNC
371 stm %r8,%r9,__PT_PSW(%r11)
372 mvc __PT_INT_CODE(4,%r11),__LC_PGM_ILC
373 mvc __PT_INT_PARM_LONG(4,%r11),__LC_TRANS_EXC_CODE
374 tm __LC_PGM_ILC+3,0x80 # check for per exception
375 jz 0f
376 l %r1,__TI_task(%r12)
377 tmh %r8,0x0001 # kernel per event ?
378 jz pgm_kprobe
379 oi __TI_flags+3(%r12),_TIF_PER_TRAP
380 mvc __THREAD_per_address(4,%r1),__LC_PER_ADDRESS
381 mvc __THREAD_per_cause(2,%r1),__LC_PER_CAUSE
382 mvc __THREAD_per_paid(1,%r1),__LC_PER_PAID
383 0: REENABLE_IRQS
384 xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
385 l %r1,BASED(.Ljump_table)
386 la %r10,0x7f
387 n %r10,__PT_INT_CODE(%r11)
388 je sysc_return
389 sll %r10,2
390 l %r1,0(%r10,%r1) # load address of handler routine
391 lr %r2,%r11 # pass pointer to pt_regs
392 basr %r14,%r1 # branch to interrupt-handler
393 j sysc_return
395 #
396 # PER event in supervisor state, must be kprobes
397 #
398 pgm_kprobe:
399 REENABLE_IRQS
400 xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
401 l %r1,BASED(.Ldo_per_trap)
402 lr %r2,%r11 # pass pointer to pt_regs
403 basr %r14,%r1 # call do_per_trap
404 j sysc_return
406 #
407 # single stepped system call
408 #
409 pgm_svcper:
410 oi __TI_flags+3(%r12),_TIF_PER_TRAP
411 mvc __LC_RETURN_PSW(4),__LC_SVC_NEW_PSW
412 mvc __LC_RETURN_PSW+4(4),BASED(.Lsysc_per)
413 lpsw __LC_RETURN_PSW # branch to sysc_per and enable irqs
415 /*
416 * IO interrupt handler routine
417 */
419 ENTRY(io_int_handler)
420 stck __LC_INT_CLOCK
421 stpt __LC_ASYNC_ENTER_TIMER
422 stm %r8,%r15,__LC_SAVE_AREA_ASYNC
423 l %r12,__LC_THREAD_INFO
424 l %r13,__LC_SVC_NEW_PSW+4
425 lm %r8,%r9,__LC_IO_OLD_PSW
426 tmh %r8,0x0001 # interrupting from user ?
427 jz io_skip
428 UPDATE_VTIME %r14,%r15,__LC_ASYNC_ENTER_TIMER
429 io_skip:
430 SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT
431 stm %r0,%r7,__PT_R0(%r11)
432 mvc __PT_R8(32,%r11),__LC_SAVE_AREA_ASYNC
433 stm %r8,%r9,__PT_PSW(%r11)
434 mvc __PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID
435 TRACE_IRQS_OFF
436 xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
437 io_loop:
438 l %r1,BASED(.Ldo_IRQ)
439 lr %r2,%r11 # pass pointer to pt_regs
440 lhi %r3,IO_INTERRUPT
441 tm __PT_INT_CODE+8(%r11),0x80 # adapter interrupt ?
442 jz io_call
443 lhi %r3,THIN_INTERRUPT
444 io_call:
445 basr %r14,%r1 # call do_IRQ
446 tm __LC_MACHINE_FLAGS+2,0x10 # MACHINE_FLAG_LPAR
447 jz io_return
448 tpi 0
449 jz io_return
450 mvc __PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID
451 j io_loop
452 io_return:
453 LOCKDEP_SYS_EXIT
454 TRACE_IRQS_ON
455 io_tif:
456 tm __TI_flags+3(%r12),_TIF_WORK_INT
457 jnz io_work # there is work to do (signals etc.)
458 io_restore:
459 mvc __LC_RETURN_PSW(8),__PT_PSW(%r11)
460 stpt __LC_EXIT_TIMER
461 lm %r0,%r15,__PT_R0(%r11)
462 lpsw __LC_RETURN_PSW
463 io_done:
465 #
466 # There is work todo, find out in which context we have been interrupted:
467 # 1) if we return to user space we can do all _TIF_WORK_INT work
468 # 2) if we return to kernel code and preemptive scheduling is enabled check
469 # the preemption counter and if it is zero call preempt_schedule_irq
470 # Before any work can be done, a switch to the kernel stack is required.
471 #
472 io_work:
473 tm __PT_PSW+1(%r11),0x01 # returning to user ?
474 jo io_work_user # yes -> do resched & signal
475 #ifdef CONFIG_PREEMPT
476 # check for preemptive scheduling
477 icm %r0,15,__TI_precount(%r12)
478 jnz io_restore # preemption disabled
479 tm __TI_flags+3(%r12),_TIF_NEED_RESCHED
480 jno io_restore
481 # switch to kernel stack
482 l %r1,__PT_R15(%r11)
483 ahi %r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
484 mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
485 xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1)
486 la %r11,STACK_FRAME_OVERHEAD(%r1)
487 lr %r15,%r1
488 # TRACE_IRQS_ON already done at io_return, call
489 # TRACE_IRQS_OFF to keep things symmetrical
490 TRACE_IRQS_OFF
491 l %r1,BASED(.Lpreempt_irq)
492 basr %r14,%r1 # call preempt_schedule_irq
493 j io_return
494 #else
495 j io_restore
496 #endif
498 #
499 # Need to do work before returning to userspace, switch to kernel stack
500 #
501 io_work_user:
502 l %r1,__LC_KERNEL_STACK
503 mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
504 xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1)
505 la %r11,STACK_FRAME_OVERHEAD(%r1)
506 lr %r15,%r1
508 #
509 # One of the work bits is on. Find out which one.
510 # Checked are: _TIF_SIGPENDING, _TIF_NOTIFY_RESUME, _TIF_NEED_RESCHED
511 # and _TIF_MCCK_PENDING
512 #
513 io_work_tif:
514 tm __TI_flags+3(%r12),_TIF_MCCK_PENDING
515 jo io_mcck_pending
516 tm __TI_flags+3(%r12),_TIF_NEED_RESCHED
517 jo io_reschedule
518 tm __TI_flags+3(%r12),_TIF_SIGPENDING
519 jo io_sigpending
520 tm __TI_flags+3(%r12),_TIF_NOTIFY_RESUME
521 jo io_notify_resume
522 j io_return # beware of critical section cleanup
524 #
525 # _TIF_MCCK_PENDING is set, call handler
526 #
527 io_mcck_pending:
528 # TRACE_IRQS_ON already done at io_return
529 l %r1,BASED(.Lhandle_mcck)
530 basr %r14,%r1 # TIF bit will be cleared by handler
531 TRACE_IRQS_OFF
532 j io_return
534 #
535 # _TIF_NEED_RESCHED is set, call schedule
536 #
537 io_reschedule:
538 # TRACE_IRQS_ON already done at io_return
539 l %r1,BASED(.Lschedule)
540 ssm __LC_SVC_NEW_PSW # reenable interrupts
541 basr %r14,%r1 # call scheduler
542 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
543 TRACE_IRQS_OFF
544 j io_return
546 #
547 # _TIF_SIGPENDING is set, call do_signal
548 #
549 io_sigpending:
550 # TRACE_IRQS_ON already done at io_return
551 l %r1,BASED(.Ldo_signal)
552 ssm __LC_SVC_NEW_PSW # reenable interrupts
553 lr %r2,%r11 # pass pointer to pt_regs
554 basr %r14,%r1 # call do_signal
555 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
556 TRACE_IRQS_OFF
557 j io_return
559 #
560 # _TIF_SIGPENDING is set, call do_signal
561 #
562 io_notify_resume:
563 # TRACE_IRQS_ON already done at io_return
564 l %r1,BASED(.Ldo_notify_resume)
565 ssm __LC_SVC_NEW_PSW # reenable interrupts
566 lr %r2,%r11 # pass pointer to pt_regs
567 basr %r14,%r1 # call do_notify_resume
568 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
569 TRACE_IRQS_OFF
570 j io_return
572 /*
573 * External interrupt handler routine
574 */
576 ENTRY(ext_int_handler)
577 stck __LC_INT_CLOCK
578 stpt __LC_ASYNC_ENTER_TIMER
579 stm %r8,%r15,__LC_SAVE_AREA_ASYNC
580 l %r12,__LC_THREAD_INFO
581 l %r13,__LC_SVC_NEW_PSW+4
582 lm %r8,%r9,__LC_EXT_OLD_PSW
583 tmh %r8,0x0001 # interrupting from user ?
584 jz ext_skip
585 UPDATE_VTIME %r14,%r15,__LC_ASYNC_ENTER_TIMER
586 ext_skip:
587 SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT
588 stm %r0,%r7,__PT_R0(%r11)
589 mvc __PT_R8(32,%r11),__LC_SAVE_AREA_ASYNC
590 stm %r8,%r9,__PT_PSW(%r11)
591 mvc __PT_INT_CODE(4,%r11),__LC_EXT_CPU_ADDR
592 mvc __PT_INT_PARM(4,%r11),__LC_EXT_PARAMS
593 TRACE_IRQS_OFF
594 l %r1,BASED(.Ldo_IRQ)
595 lr %r2,%r11 # pass pointer to pt_regs
596 lhi %r3,EXT_INTERRUPT
597 basr %r14,%r1 # call do_IRQ
598 j io_return
600 /*
601 * Load idle PSW. The second "half" of this function is in cleanup_idle.
602 */
603 ENTRY(psw_idle)
604 st %r3,__SF_EMPTY(%r15)
605 basr %r1,0
606 la %r1,psw_idle_lpsw+4-.(%r1)
607 st %r1,__SF_EMPTY+4(%r15)
608 oi __SF_EMPTY+4(%r15),0x80
609 stck __CLOCK_IDLE_ENTER(%r2)
610 stpt __TIMER_IDLE_ENTER(%r2)
611 psw_idle_lpsw:
612 lpsw __SF_EMPTY(%r15)
613 br %r14
614 psw_idle_end:
616 __critical_end:
618 /*
619 * Machine check handler routines
620 */
622 ENTRY(mcck_int_handler)
623 stck __LC_MCCK_CLOCK
624 spt __LC_CPU_TIMER_SAVE_AREA # revalidate cpu timer
625 lm %r0,%r15,__LC_GPREGS_SAVE_AREA # revalidate gprs
626 l %r12,__LC_THREAD_INFO
627 l %r13,__LC_SVC_NEW_PSW+4
628 lm %r8,%r9,__LC_MCK_OLD_PSW
629 tm __LC_MCCK_CODE,0x80 # system damage?
630 jo mcck_panic # yes -> rest of mcck code invalid
631 la %r14,__LC_CPU_TIMER_SAVE_AREA
632 mvc __LC_MCCK_ENTER_TIMER(8),0(%r14)
633 tm __LC_MCCK_CODE+5,0x02 # stored cpu timer value valid?
634 jo 3f
635 la %r14,__LC_SYNC_ENTER_TIMER
636 clc 0(8,%r14),__LC_ASYNC_ENTER_TIMER
637 jl 0f
638 la %r14,__LC_ASYNC_ENTER_TIMER
639 0: clc 0(8,%r14),__LC_EXIT_TIMER
640 jl 1f
641 la %r14,__LC_EXIT_TIMER
642 1: clc 0(8,%r14),__LC_LAST_UPDATE_TIMER
643 jl 2f
644 la %r14,__LC_LAST_UPDATE_TIMER
645 2: spt 0(%r14)
646 mvc __LC_MCCK_ENTER_TIMER(8),0(%r14)
647 3: tm __LC_MCCK_CODE+2,0x09 # mwp + ia of old psw valid?
648 jno mcck_panic # no -> skip cleanup critical
649 tm %r8,0x0001 # interrupting from user ?
650 jz mcck_skip
651 UPDATE_VTIME %r14,%r15,__LC_MCCK_ENTER_TIMER
652 mcck_skip:
653 SWITCH_ASYNC __LC_GPREGS_SAVE_AREA+32,__LC_PANIC_STACK,PAGE_SHIFT
654 stm %r0,%r7,__PT_R0(%r11)
655 mvc __PT_R8(32,%r11),__LC_GPREGS_SAVE_AREA+32
656 stm %r8,%r9,__PT_PSW(%r11)
657 xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
658 l %r1,BASED(.Ldo_machine_check)
659 lr %r2,%r11 # pass pointer to pt_regs
660 basr %r14,%r1 # call s390_do_machine_check
661 tm __PT_PSW+1(%r11),0x01 # returning to user ?
662 jno mcck_return
663 l %r1,__LC_KERNEL_STACK # switch to kernel stack
664 mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
665 xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1)
666 la %r11,STACK_FRAME_OVERHEAD(%r15)
667 lr %r15,%r1
668 ssm __LC_PGM_NEW_PSW # turn dat on, keep irqs off
669 tm __TI_flags+3(%r12),_TIF_MCCK_PENDING
670 jno mcck_return
671 TRACE_IRQS_OFF
672 l %r1,BASED(.Lhandle_mcck)
673 basr %r14,%r1 # call s390_handle_mcck
674 TRACE_IRQS_ON
675 mcck_return:
676 mvc __LC_RETURN_MCCK_PSW(8),__PT_PSW(%r11) # move return PSW
677 tm __LC_RETURN_MCCK_PSW+1,0x01 # returning to user ?
678 jno 0f
679 lm %r0,%r15,__PT_R0(%r11)
680 stpt __LC_EXIT_TIMER
681 lpsw __LC_RETURN_MCCK_PSW
682 0: lm %r0,%r15,__PT_R0(%r11)
683 lpsw __LC_RETURN_MCCK_PSW
685 mcck_panic:
686 l %r14,__LC_PANIC_STACK
687 slr %r14,%r15
688 sra %r14,PAGE_SHIFT
689 jz 0f
690 l %r15,__LC_PANIC_STACK
691 j mcck_skip
692 0: ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
693 j mcck_skip
695 #
696 # PSW restart interrupt handler
697 #
698 ENTRY(restart_int_handler)
699 st %r15,__LC_SAVE_AREA_RESTART
700 l %r15,__LC_RESTART_STACK
701 ahi %r15,-__PT_SIZE # create pt_regs on stack
702 xc 0(__PT_SIZE,%r15),0(%r15)
703 stm %r0,%r14,__PT_R0(%r15)
704 mvc __PT_R15(4,%r15),__LC_SAVE_AREA_RESTART
705 mvc __PT_PSW(8,%r15),__LC_RST_OLD_PSW # store restart old psw
706 ahi %r15,-STACK_FRAME_OVERHEAD # create stack frame on stack
707 xc 0(STACK_FRAME_OVERHEAD,%r15),0(%r15)
708 l %r1,__LC_RESTART_FN # load fn, parm & source cpu
709 l %r2,__LC_RESTART_DATA
710 l %r3,__LC_RESTART_SOURCE
711 ltr %r3,%r3 # test source cpu address
712 jm 1f # negative -> skip source stop
713 0: sigp %r4,%r3,SIGP_SENSE # sigp sense to source cpu
714 brc 10,0b # wait for status stored
715 1: basr %r14,%r1 # call function
716 stap __SF_EMPTY(%r15) # store cpu address
717 lh %r3,__SF_EMPTY(%r15)
718 2: sigp %r4,%r3,SIGP_STOP # sigp stop to current cpu
719 brc 2,2b
720 3: j 3b
722 .section .kprobes.text, "ax"
724 #ifdef CONFIG_CHECK_STACK
725 /*
726 * The synchronous or the asynchronous stack overflowed. We are dead.
727 * No need to properly save the registers, we are going to panic anyway.
728 * Setup a pt_regs so that show_trace can provide a good call trace.
729 */
730 stack_overflow:
731 l %r15,__LC_PANIC_STACK # change to panic stack
732 la %r11,STACK_FRAME_OVERHEAD(%r15)
733 stm %r0,%r7,__PT_R0(%r11)
734 stm %r8,%r9,__PT_PSW(%r11)
735 mvc __PT_R8(32,%r11),0(%r14)
736 l %r1,BASED(1f)
737 xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
738 lr %r2,%r11 # pass pointer to pt_regs
739 br %r1 # branch to kernel_stack_overflow
740 1: .long kernel_stack_overflow
741 #endif
743 cleanup_table:
744 .long system_call + 0x80000000
745 .long sysc_do_svc + 0x80000000
746 .long sysc_tif + 0x80000000
747 .long sysc_restore + 0x80000000
748 .long sysc_done + 0x80000000
749 .long io_tif + 0x80000000
750 .long io_restore + 0x80000000
751 .long io_done + 0x80000000
752 .long psw_idle + 0x80000000
753 .long psw_idle_end + 0x80000000
755 cleanup_critical:
756 cl %r9,BASED(cleanup_table) # system_call
757 jl 0f
758 cl %r9,BASED(cleanup_table+4) # sysc_do_svc
759 jl cleanup_system_call
760 cl %r9,BASED(cleanup_table+8) # sysc_tif
761 jl 0f
762 cl %r9,BASED(cleanup_table+12) # sysc_restore
763 jl cleanup_sysc_tif
764 cl %r9,BASED(cleanup_table+16) # sysc_done
765 jl cleanup_sysc_restore
766 cl %r9,BASED(cleanup_table+20) # io_tif
767 jl 0f
768 cl %r9,BASED(cleanup_table+24) # io_restore
769 jl cleanup_io_tif
770 cl %r9,BASED(cleanup_table+28) # io_done
771 jl cleanup_io_restore
772 cl %r9,BASED(cleanup_table+32) # psw_idle
773 jl 0f
774 cl %r9,BASED(cleanup_table+36) # psw_idle_end
775 jl cleanup_idle
776 0: br %r14
778 cleanup_system_call:
779 # check if stpt has been executed
780 cl %r9,BASED(cleanup_system_call_insn)
781 jh 0f
782 mvc __LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER
783 chi %r11,__LC_SAVE_AREA_ASYNC
784 je 0f
785 mvc __LC_SYNC_ENTER_TIMER(8),__LC_MCCK_ENTER_TIMER
786 0: # check if stm has been executed
787 cl %r9,BASED(cleanup_system_call_insn+4)
788 jh 0f
789 mvc __LC_SAVE_AREA_SYNC(32),0(%r11)
790 0: # set up saved registers r12, and r13
791 st %r12,16(%r11) # r12 thread-info pointer
792 st %r13,20(%r11) # r13 literal-pool pointer
793 # check if the user time calculation has been done
794 cl %r9,BASED(cleanup_system_call_insn+8)
795 jh 0f
796 l %r10,__LC_EXIT_TIMER
797 l %r15,__LC_EXIT_TIMER+4
798 SUB64 %r10,%r15,__LC_SYNC_ENTER_TIMER
799 ADD64 %r10,%r15,__LC_USER_TIMER
800 st %r10,__LC_USER_TIMER
801 st %r15,__LC_USER_TIMER+4
802 0: # check if the system time calculation has been done
803 cl %r9,BASED(cleanup_system_call_insn+12)
804 jh 0f
805 l %r10,__LC_LAST_UPDATE_TIMER
806 l %r15,__LC_LAST_UPDATE_TIMER+4
807 SUB64 %r10,%r15,__LC_EXIT_TIMER
808 ADD64 %r10,%r15,__LC_SYSTEM_TIMER
809 st %r10,__LC_SYSTEM_TIMER
810 st %r15,__LC_SYSTEM_TIMER+4
811 0: # update accounting time stamp
812 mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
813 # set up saved register 11
814 l %r15,__LC_KERNEL_STACK
815 la %r9,STACK_FRAME_OVERHEAD(%r15)
816 st %r9,12(%r11) # r11 pt_regs pointer
817 # fill pt_regs
818 mvc __PT_R8(32,%r9),__LC_SAVE_AREA_SYNC
819 stm %r0,%r7,__PT_R0(%r9)
820 mvc __PT_PSW(8,%r9),__LC_SVC_OLD_PSW
821 mvc __PT_INT_CODE(4,%r9),__LC_SVC_ILC
822 # setup saved register 15
823 st %r15,28(%r11) # r15 stack pointer
824 # set new psw address and exit
825 l %r9,BASED(cleanup_table+4) # sysc_do_svc + 0x80000000
826 br %r14
827 cleanup_system_call_insn:
828 .long system_call + 0x80000000
829 .long sysc_stm + 0x80000000
830 .long sysc_vtime + 0x80000000 + 36
831 .long sysc_vtime + 0x80000000 + 76
833 cleanup_sysc_tif:
834 l %r9,BASED(cleanup_table+8) # sysc_tif + 0x80000000
835 br %r14
837 cleanup_sysc_restore:
838 cl %r9,BASED(cleanup_sysc_restore_insn)
839 jhe 0f
840 l %r9,12(%r11) # get saved pointer to pt_regs
841 mvc __LC_RETURN_PSW(8),__PT_PSW(%r9)
842 mvc 0(32,%r11),__PT_R8(%r9)
843 lm %r0,%r7,__PT_R0(%r9)
844 0: lm %r8,%r9,__LC_RETURN_PSW
845 br %r14
846 cleanup_sysc_restore_insn:
847 .long sysc_done - 4 + 0x80000000
849 cleanup_io_tif:
850 l %r9,BASED(cleanup_table+20) # io_tif + 0x80000000
851 br %r14
853 cleanup_io_restore:
854 cl %r9,BASED(cleanup_io_restore_insn)
855 jhe 0f
856 l %r9,12(%r11) # get saved r11 pointer to pt_regs
857 mvc __LC_RETURN_PSW(8),__PT_PSW(%r9)
858 mvc 0(32,%r11),__PT_R8(%r9)
859 lm %r0,%r7,__PT_R0(%r9)
860 0: lm %r8,%r9,__LC_RETURN_PSW
861 br %r14
862 cleanup_io_restore_insn:
863 .long io_done - 4 + 0x80000000
865 cleanup_idle:
866 # copy interrupt clock & cpu timer
867 mvc __CLOCK_IDLE_EXIT(8,%r2),__LC_INT_CLOCK
868 mvc __TIMER_IDLE_EXIT(8,%r2),__LC_ASYNC_ENTER_TIMER
869 chi %r11,__LC_SAVE_AREA_ASYNC
870 je 0f
871 mvc __CLOCK_IDLE_EXIT(8,%r2),__LC_MCCK_CLOCK
872 mvc __TIMER_IDLE_EXIT(8,%r2),__LC_MCCK_ENTER_TIMER
873 0: # check if stck has been executed
874 cl %r9,BASED(cleanup_idle_insn)
875 jhe 1f
876 mvc __CLOCK_IDLE_ENTER(8,%r2),__CLOCK_IDLE_EXIT(%r2)
877 mvc __TIMER_IDLE_ENTER(8,%r2),__TIMER_IDLE_EXIT(%r3)
878 1: # account system time going idle
879 lm %r9,%r10,__LC_STEAL_TIMER
880 ADD64 %r9,%r10,__CLOCK_IDLE_ENTER(%r2)
881 SUB64 %r9,%r10,__LC_LAST_UPDATE_CLOCK
882 stm %r9,%r10,__LC_STEAL_TIMER
883 mvc __LC_LAST_UPDATE_CLOCK(8),__CLOCK_IDLE_EXIT(%r2)
884 lm %r9,%r10,__LC_SYSTEM_TIMER
885 ADD64 %r9,%r10,__LC_LAST_UPDATE_TIMER
886 SUB64 %r9,%r10,__TIMER_IDLE_ENTER(%r2)
887 stm %r9,%r10,__LC_SYSTEM_TIMER
888 mvc __LC_LAST_UPDATE_TIMER(8),__TIMER_IDLE_EXIT(%r2)
889 # prepare return psw
890 n %r8,BASED(cleanup_idle_wait) # clear irq & wait state bits
891 l %r9,24(%r11) # return from psw_idle
892 br %r14
893 cleanup_idle_insn:
894 .long psw_idle_lpsw + 0x80000000
895 cleanup_idle_wait:
896 .long 0xfcfdffff
898 /*
899 * Integer constants
900 */
901 .align 4
902 .Lnr_syscalls:
903 .long NR_syscalls
904 .Lvtimer_max:
905 .quad 0x7fffffffffffffff
907 /*
908 * Symbol constants
909 */
910 .Ldo_machine_check: .long s390_do_machine_check
911 .Lhandle_mcck: .long s390_handle_mcck
912 .Ldo_IRQ: .long do_IRQ
913 .Ldo_signal: .long do_signal
914 .Ldo_notify_resume: .long do_notify_resume
915 .Ldo_per_trap: .long do_per_trap
916 .Ljump_table: .long pgm_check_table
917 .Lschedule: .long schedule
918 #ifdef CONFIG_PREEMPT
919 .Lpreempt_irq: .long preempt_schedule_irq
920 #endif
921 .Ltrace_enter: .long do_syscall_trace_enter
922 .Ltrace_exit: .long do_syscall_trace_exit
923 .Lschedule_tail: .long schedule_tail
924 .Lsysc_per: .long sysc_per + 0x80000000
925 #ifdef CONFIG_TRACE_IRQFLAGS
926 .Lhardirqs_on: .long trace_hardirqs_on_caller
927 .Lhardirqs_off: .long trace_hardirqs_off_caller
928 #endif
929 #ifdef CONFIG_LOCKDEP
930 .Llockdep_sys_exit: .long lockdep_sys_exit
931 #endif
932 .Lcritical_start: .long __critical_start + 0x80000000
933 .Lcritical_length: .long __critical_end - __critical_start
935 .section .rodata, "a"
936 #define SYSCALL(esa,esame,emu) .long esa
937 .globl sys_call_table
938 sys_call_table:
939 #include "syscalls.S"
940 #undef SYSCALL