2 * S390 low-level entry points.
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>
11 #include <linux/init.h>
12 #include <linux/linkage.h>
13 #include <asm/processor.h>
14 #include <asm/cache.h>
15 #include <asm/errno.h>
16 #include <asm/ptrace.h>
17 #include <asm/thread_info.h>
18 #include <asm/asm-offsets.h>
19 #include <asm/unistd.h>
25 __PT_R1 = __PT_GPRS + 8
26 __PT_R2 = __PT_GPRS + 16
27 __PT_R3 = __PT_GPRS + 24
28 __PT_R4 = __PT_GPRS + 32
29 __PT_R5 = __PT_GPRS + 40
30 __PT_R6 = __PT_GPRS + 48
31 __PT_R7 = __PT_GPRS + 56
32 __PT_R8 = __PT_GPRS + 64
33 __PT_R9 = __PT_GPRS + 72
34 __PT_R10 = __PT_GPRS + 80
35 __PT_R11 = __PT_GPRS + 88
36 __PT_R12 = __PT_GPRS + 96
37 __PT_R13 = __PT_GPRS + 104
38 __PT_R14 = __PT_GPRS + 112
39 __PT_R15 = __PT_GPRS + 120
41 STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
42 STACK_SIZE = 1 << STACK_SHIFT
43 STACK_INIT = STACK_SIZE - STACK_FRAME_OVERHEAD - __PT_SIZE
45 _TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
46 _TIF_MCCK_PENDING | _TIF_PER_TRAP )
47 _TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
49 _TIF_TRACE = (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | \
50 _TIF_SYSCALL_TRACEPOINT)
52 #define BASED(name) name-system_call(%r13)
55 #ifdef CONFIG_TRACE_IRQFLAGS
57 brasl %r14,trace_hardirqs_on_caller
62 #ifdef CONFIG_TRACE_IRQFLAGS
64 brasl %r14,trace_hardirqs_off_caller
68 .macro LOCKDEP_SYS_EXIT
70 tm __PT_PSW+1(%r11),0x01 # returning to user ?
72 brasl %r14,lockdep_sys_exit
77 #if defined(CONFIG_KVM) || defined(CONFIG_KVM_MODULE)
78 tm __LC_MACHINE_FLAGS+6,0x20 # MACHINE_FLAG_LPP
80 .insn s,0xb2800000,\newpp
84 .macro HANDLE_SIE_INTERCEPT scratch,reason
85 #if defined(CONFIG_KVM) || defined(CONFIG_KVM_MODULE)
86 tmhh %r8,0x0001 # interrupting from user ?
89 slg \scratch,BASED(.Lsie_critical)
90 clg \scratch,BASED(.Lsie_critical_length)
92 # Some program interrupts are suppressing (e.g. protection).
93 # We must also check the instruction after SIE in that case.
94 # do_protection_exception will rewind to rewind_pad
99 lg %r14,__SF_EMPTY(%r15) # get control block pointer
100 LPP __SF_EMPTY+16(%r15) # set host id
101 ni __SIE_PROG0C+3(%r14),0xfe # no longer in SIE
102 lctlg %c1,%c1,__LC_USER_ASCE # load primary asce
103 larl %r9,sie_exit # skip forward to sie_exit
104 mvi __SF_EMPTY+31(%r15),\reason # set exit reason
108 .macro CHECK_STACK stacksize,savearea
109 #ifdef CONFIG_CHECK_STACK
110 tml %r15,\stacksize - CONFIG_STACK_GUARD
116 .macro SWITCH_ASYNC savearea,stack,shift
117 tmhh %r8,0x0001 # interrupting from user ?
120 slg %r14,BASED(.Lcritical_start)
121 clg %r14,BASED(.Lcritical_length)
123 lghi %r11,\savearea # inside critical section, do cleanup
124 brasl %r14,cleanup_critical
125 tmhh %r8,0x0001 # retest problem state after cleanup
127 0: lg %r14,\stack # are we already on the target stack?
129 srag %r14,%r14,\shift
131 CHECK_STACK 1<<\shift,\savearea
132 aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
134 1: lg %r15,\stack # load target stack
135 2: la %r11,STACK_FRAME_OVERHEAD(%r15)
138 .macro UPDATE_VTIME scratch,enter_timer
139 lg \scratch,__LC_EXIT_TIMER
140 slg \scratch,\enter_timer
141 alg \scratch,__LC_USER_TIMER
142 stg \scratch,__LC_USER_TIMER
143 lg \scratch,__LC_LAST_UPDATE_TIMER
144 slg \scratch,__LC_EXIT_TIMER
145 alg \scratch,__LC_SYSTEM_TIMER
146 stg \scratch,__LC_SYSTEM_TIMER
147 mvc __LC_LAST_UPDATE_TIMER(8),\enter_timer
150 .macro LAST_BREAK scratch
151 srag \scratch,%r10,23
153 stg %r10,__TI_last_break(%r12)
157 stg %r8,__LC_RETURN_PSW
158 ni __LC_RETURN_PSW,0xbf
163 #ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
164 .insn s,0xb27c0000,\savearea # store clock fast
166 .insn s,0xb2050000,\savearea # store clock
170 .section .kprobes.text, "ax"
173 * Scheduler resume function, called by switch_to
174 * gpr2 = (task_struct *) prev
175 * gpr3 = (task_struct *) next
180 stmg %r6,%r15,__SF_GPRS(%r15) # store gprs of prev task
181 stg %r15,__THREAD_ksp(%r2) # store kernel stack of prev
182 lg %r4,__THREAD_info(%r2) # get thread_info of prev
183 lg %r5,__THREAD_info(%r3) # get thread_info of next
185 aghi %r15,STACK_INIT # end of kernel stack of next
186 stg %r3,__LC_CURRENT # store task struct of next
187 stg %r5,__LC_THREAD_INFO # store thread info of next
188 stg %r15,__LC_KERNEL_STACK # store end of kernel stack
189 lctl %c4,%c4,__TASK_pid(%r3) # load pid to control reg. 4
190 mvc __LC_CURRENT_PID+4(4,%r0),__TASK_pid(%r3) # store pid of next
191 lg %r15,__THREAD_ksp(%r3) # load kernel stack of next
192 tm __TI_flags+7(%r4),_TIF_MCCK_PENDING # machine check pending?
194 ni __TI_flags+7(%r4),255-_TIF_MCCK_PENDING # clear flag in prev
195 oi __TI_flags+7(%r5),_TIF_MCCK_PENDING # set it in next
196 0: lmg %r6,%r15,__SF_GPRS(%r15) # load gprs of next task
201 * SVC interrupt handler routine. System calls are synchronous events and
202 * are executed with interrupts enabled.
206 stpt __LC_SYNC_ENTER_TIMER
208 stmg %r8,%r15,__LC_SAVE_AREA_SYNC
209 lg %r10,__LC_LAST_BREAK
210 lg %r12,__LC_THREAD_INFO
212 lg %r15,__LC_KERNEL_STACK
213 la %r11,STACK_FRAME_OVERHEAD(%r15) # pointer to pt_regs
215 UPDATE_VTIME %r13,__LC_SYNC_ENTER_TIMER
217 stmg %r0,%r7,__PT_R0(%r11)
218 mvc __PT_R8(64,%r11),__LC_SAVE_AREA_SYNC
219 mvc __PT_PSW(16,%r11),__LC_SVC_OLD_PSW
220 mvc __PT_INT_CODE(4,%r11),__LC_SVC_ILC
222 oi __TI_flags+7(%r12),_TIF_SYSCALL
223 lg %r10,__TI_sysc_table(%r12) # address of system call table
224 llgh %r8,__PT_INT_CODE+2(%r11)
225 slag %r8,%r8,2 # shift and test for svc 0
227 # svc 0: system call number in %r1
228 llgfr %r1,%r1 # clear high word in r1
231 sth %r1,__PT_INT_CODE+2(%r11)
234 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
235 stg %r2,__PT_ORIG_GPR2(%r11)
236 stg %r7,STACK_FRAME_OVERHEAD(%r15)
237 lgf %r9,0(%r8,%r10) # get system call add.
238 tm __TI_flags+6(%r12),_TIF_TRACE >> 8
240 basr %r14,%r9 # call sys_xxxx
241 stg %r2,__PT_R2(%r11) # store return value
246 tm __PT_PSW+1(%r11),0x01 # returning to user ?
248 tm __TI_flags+7(%r12),_TIF_WORK_SVC
249 jnz sysc_work # check for work
250 ni __TI_flags+7(%r12),255-_TIF_SYSCALL
252 lg %r14,__LC_VDSO_PER_CPU
253 lmg %r0,%r10,__PT_R0(%r11)
254 mvc __LC_RETURN_PSW(16),__PT_PSW(%r11)
256 mvc __VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER
257 lmg %r11,%r15,__PT_R11(%r11)
258 lpswe __LC_RETURN_PSW
262 # One of the work bits is on. Find out which one.
265 tm __TI_flags+7(%r12),_TIF_MCCK_PENDING
267 tm __TI_flags+7(%r12),_TIF_NEED_RESCHED
269 tm __TI_flags+7(%r12),_TIF_PER_TRAP
271 tm __TI_flags+7(%r12),_TIF_SIGPENDING
273 tm __TI_flags+7(%r12),_TIF_NOTIFY_RESUME
274 jo sysc_notify_resume
275 j sysc_return # beware of critical section cleanup
278 # _TIF_NEED_RESCHED is set, call schedule
281 larl %r14,sysc_return
285 # _TIF_MCCK_PENDING is set, call handler
288 larl %r14,sysc_return
289 jg s390_handle_mcck # TIF bit will be cleared by handler
292 # _TIF_SIGPENDING is set, call do_signal
295 lgr %r2,%r11 # pass pointer to pt_regs
297 tm __TI_flags+7(%r12),_TIF_SYSCALL
299 lmg %r2,%r7,__PT_R2(%r11) # load svc arguments
300 lghi %r8,0 # svc 0 returns -ENOSYS
301 llgh %r1,__PT_INT_CODE+2(%r11) # load new svc number
303 jnl sysc_nr_ok # invalid svc number -> do svc 0
305 j sysc_nr_ok # restart svc
308 # _TIF_NOTIFY_RESUME is set, call do_notify_resume
311 lgr %r2,%r11 # pass pointer to pt_regs
312 larl %r14,sysc_return
316 # _TIF_PER_TRAP is set, call do_per_trap
319 ni __TI_flags+7(%r12),255-_TIF_PER_TRAP
320 lgr %r2,%r11 # pass pointer to pt_regs
321 larl %r14,sysc_return
325 # call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
326 # and after the system call
329 lgr %r2,%r11 # pass pointer to pt_regs
331 llgh %r0,__PT_INT_CODE+2(%r11)
332 stg %r0,__PT_R2(%r11)
333 brasl %r14,do_syscall_trace_enter
340 lmg %r3,%r7,__PT_R3(%r11)
341 stg %r7,STACK_FRAME_OVERHEAD(%r15)
342 lg %r2,__PT_ORIG_GPR2(%r11)
343 basr %r14,%r9 # call sys_xxx
344 stg %r2,__PT_R2(%r11) # store return value
346 tm __TI_flags+6(%r12),_TIF_TRACE >> 8
348 lgr %r2,%r11 # pass pointer to pt_regs
349 larl %r14,sysc_return
350 jg do_syscall_trace_exit
353 # a new process exits the kernel with ret_from_fork
356 la %r11,STACK_FRAME_OVERHEAD(%r15)
357 lg %r12,__LC_THREAD_INFO
358 brasl %r14,schedule_tail
360 ssm __LC_SVC_NEW_PSW # reenable interrupts
361 tm __PT_PSW+1(%r11),0x01 # forking a kernel thread ?
363 # it's a kernel thread
364 lmg %r9,%r10,__PT_R9(%r11) # load gprs
365 ENTRY(kernel_thread_starter)
371 * Program check handler routine
374 ENTRY(pgm_check_handler)
375 stpt __LC_SYNC_ENTER_TIMER
376 stmg %r8,%r15,__LC_SAVE_AREA_SYNC
377 lg %r10,__LC_LAST_BREAK
378 lg %r12,__LC_THREAD_INFO
379 larl %r13,system_call
380 lmg %r8,%r9,__LC_PGM_OLD_PSW
381 HANDLE_SIE_INTERCEPT %r14,1
382 tmhh %r8,0x0001 # test problem state bit
383 jnz 1f # -> fault in user space
384 tmhh %r8,0x4000 # PER bit set in old PSW ?
385 jnz 0f # -> enabled, can't be a double fault
386 tm __LC_PGM_ILC+3,0x80 # check for per exception
387 jnz pgm_svcper # -> single stepped svc
388 0: CHECK_STACK STACK_SIZE,__LC_SAVE_AREA_SYNC
389 aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
391 1: UPDATE_VTIME %r14,__LC_SYNC_ENTER_TIMER
393 lg %r15,__LC_KERNEL_STACK
394 lg %r14,__TI_task(%r12)
395 lghi %r13,__LC_PGM_TDB
396 tm __LC_PGM_ILC+2,0x02 # check for transaction abort
398 mvc __THREAD_trap_tdb(256,%r14),0(%r13)
399 2: la %r11,STACK_FRAME_OVERHEAD(%r15)
400 stmg %r0,%r7,__PT_R0(%r11)
401 mvc __PT_R8(64,%r11),__LC_SAVE_AREA_SYNC
402 stmg %r8,%r9,__PT_PSW(%r11)
403 mvc __PT_INT_CODE(4,%r11),__LC_PGM_ILC
404 mvc __PT_INT_PARM_LONG(8,%r11),__LC_TRANS_EXC_CODE
405 stg %r10,__PT_ARGS(%r11)
406 tm __LC_PGM_ILC+3,0x80 # check for per exception
408 tmhh %r8,0x0001 # kernel per event ?
410 oi __TI_flags+7(%r12),_TIF_PER_TRAP
411 mvc __THREAD_per_address(8,%r14),__LC_PER_ADDRESS
412 mvc __THREAD_per_cause(2,%r14),__LC_PER_CAUSE
413 mvc __THREAD_per_paid(1,%r14),__LC_PER_PAID
415 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
416 larl %r1,pgm_check_table
417 llgh %r10,__PT_INT_CODE+2(%r11)
421 lgf %r1,0(%r10,%r1) # load address of handler routine
422 lgr %r2,%r11 # pass pointer to pt_regs
423 basr %r14,%r1 # branch to interrupt-handler
427 # PER event in supervisor state, must be kprobes
431 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
432 lgr %r2,%r11 # pass pointer to pt_regs
433 brasl %r14,do_per_trap
437 # single stepped system call
440 oi __TI_flags+7(%r12),_TIF_PER_TRAP
441 mvc __LC_RETURN_PSW(8),__LC_SVC_NEW_PSW
443 stg %r14,__LC_RETURN_PSW+8
444 lpswe __LC_RETURN_PSW # branch to sysc_per and enable irqs
447 * IO interrupt handler routine
449 ENTRY(io_int_handler)
451 stpt __LC_ASYNC_ENTER_TIMER
452 stmg %r8,%r15,__LC_SAVE_AREA_ASYNC
453 lg %r10,__LC_LAST_BREAK
454 lg %r12,__LC_THREAD_INFO
455 larl %r13,system_call
456 lmg %r8,%r9,__LC_IO_OLD_PSW
457 HANDLE_SIE_INTERCEPT %r14,2
458 SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT
459 tmhh %r8,0x0001 # interrupting from user?
461 UPDATE_VTIME %r14,__LC_ASYNC_ENTER_TIMER
464 stmg %r0,%r7,__PT_R0(%r11)
465 mvc __PT_R8(64,%r11),__LC_SAVE_AREA_ASYNC
466 stmg %r8,%r9,__PT_PSW(%r11)
467 mvc __PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID
469 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
471 lgr %r2,%r11 # pass pointer to pt_regs
472 lghi %r3,IO_INTERRUPT
473 tm __PT_INT_CODE+8(%r11),0x80 # adapter interrupt ?
475 lghi %r3,THIN_INTERRUPT
478 tm __LC_MACHINE_FLAGS+6,0x10 # MACHINE_FLAG_LPAR
482 mvc __PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID
488 tm __TI_flags+7(%r12),_TIF_WORK_INT
489 jnz io_work # there is work to do (signals etc.)
491 lg %r14,__LC_VDSO_PER_CPU
492 lmg %r0,%r10,__PT_R0(%r11)
493 mvc __LC_RETURN_PSW(16),__PT_PSW(%r11)
495 mvc __VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER
496 lmg %r11,%r15,__PT_R11(%r11)
497 lpswe __LC_RETURN_PSW
501 # There is work todo, find out in which context we have been interrupted:
502 # 1) if we return to user space we can do all _TIF_WORK_INT work
503 # 2) if we return to kernel code and kvm is enabled check if we need to
504 # modify the psw to leave SIE
505 # 3) if we return to kernel code and preemptive scheduling is enabled check
506 # the preemption counter and if it is zero call preempt_schedule_irq
507 # Before any work can be done, a switch to the kernel stack is required.
510 tm __PT_PSW+1(%r11),0x01 # returning to user ?
511 jo io_work_user # yes -> do resched & signal
512 #ifdef CONFIG_PREEMPT
513 # check for preemptive scheduling
514 icm %r0,15,__TI_precount(%r12)
515 jnz io_restore # preemption is disabled
516 tm __TI_flags+7(%r12),_TIF_NEED_RESCHED
518 # switch to kernel stack
519 lg %r1,__PT_R15(%r11)
520 aghi %r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
521 mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
522 xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1)
523 la %r11,STACK_FRAME_OVERHEAD(%r1)
525 # TRACE_IRQS_ON already done at io_return, call
526 # TRACE_IRQS_OFF to keep things symmetrical
528 brasl %r14,preempt_schedule_irq
535 # Need to do work before returning to userspace, switch to kernel stack
538 lg %r1,__LC_KERNEL_STACK
539 mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
540 xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1)
541 la %r11,STACK_FRAME_OVERHEAD(%r1)
545 # One of the work bits is on. Find out which one.
546 # Checked are: _TIF_SIGPENDING, _TIF_NOTIFY_RESUME, _TIF_NEED_RESCHED
547 # and _TIF_MCCK_PENDING
550 tm __TI_flags+7(%r12),_TIF_MCCK_PENDING
552 tm __TI_flags+7(%r12),_TIF_NEED_RESCHED
554 tm __TI_flags+7(%r12),_TIF_SIGPENDING
556 tm __TI_flags+7(%r12),_TIF_NOTIFY_RESUME
558 j io_return # beware of critical section cleanup
561 # _TIF_MCCK_PENDING is set, call handler
564 # TRACE_IRQS_ON already done at io_return
565 brasl %r14,s390_handle_mcck # TIF bit will be cleared by handler
570 # _TIF_NEED_RESCHED is set, call schedule
573 # TRACE_IRQS_ON already done at io_return
574 ssm __LC_SVC_NEW_PSW # reenable interrupts
575 brasl %r14,schedule # call scheduler
576 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
581 # _TIF_SIGPENDING or is set, call do_signal
584 # TRACE_IRQS_ON already done at io_return
585 ssm __LC_SVC_NEW_PSW # reenable interrupts
586 lgr %r2,%r11 # pass pointer to pt_regs
588 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
593 # _TIF_NOTIFY_RESUME or is set, call do_notify_resume
596 # TRACE_IRQS_ON already done at io_return
597 ssm __LC_SVC_NEW_PSW # reenable interrupts
598 lgr %r2,%r11 # pass pointer to pt_regs
599 brasl %r14,do_notify_resume
600 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
605 * External interrupt handler routine
607 ENTRY(ext_int_handler)
609 stpt __LC_ASYNC_ENTER_TIMER
610 stmg %r8,%r15,__LC_SAVE_AREA_ASYNC
611 lg %r10,__LC_LAST_BREAK
612 lg %r12,__LC_THREAD_INFO
613 larl %r13,system_call
614 lmg %r8,%r9,__LC_EXT_OLD_PSW
615 HANDLE_SIE_INTERCEPT %r14,3
616 SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT
617 tmhh %r8,0x0001 # interrupting from user ?
619 UPDATE_VTIME %r14,__LC_ASYNC_ENTER_TIMER
622 stmg %r0,%r7,__PT_R0(%r11)
623 mvc __PT_R8(64,%r11),__LC_SAVE_AREA_ASYNC
624 stmg %r8,%r9,__PT_PSW(%r11)
625 lghi %r1,__LC_EXT_PARAMS2
626 mvc __PT_INT_CODE(4,%r11),__LC_EXT_CPU_ADDR
627 mvc __PT_INT_PARM(4,%r11),__LC_EXT_PARAMS
628 mvc __PT_INT_PARM_LONG(8,%r11),0(%r1)
630 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
631 lgr %r2,%r11 # pass pointer to pt_regs
632 lghi %r3,EXT_INTERRUPT
637 * Load idle PSW. The second "half" of this function is in cleanup_idle.
640 stg %r3,__SF_EMPTY(%r15)
641 larl %r1,psw_idle_lpsw+4
642 stg %r1,__SF_EMPTY+8(%r15)
643 STCK __CLOCK_IDLE_ENTER(%r2)
644 stpt __TIMER_IDLE_ENTER(%r2)
646 lpswe __SF_EMPTY(%r15)
653 * Machine check handler routines
655 ENTRY(mcck_int_handler)
657 la %r1,4095 # revalidate r1
658 spt __LC_CPU_TIMER_SAVE_AREA-4095(%r1) # revalidate cpu timer
659 lmg %r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r1)# revalidate gprs
660 lg %r10,__LC_LAST_BREAK
661 lg %r12,__LC_THREAD_INFO
662 larl %r13,system_call
663 lmg %r8,%r9,__LC_MCK_OLD_PSW
664 HANDLE_SIE_INTERCEPT %r14,4
665 tm __LC_MCCK_CODE,0x80 # system damage?
666 jo mcck_panic # yes -> rest of mcck code invalid
667 lghi %r14,__LC_CPU_TIMER_SAVE_AREA
668 mvc __LC_MCCK_ENTER_TIMER(8),0(%r14)
669 tm __LC_MCCK_CODE+5,0x02 # stored cpu timer value valid?
671 la %r14,__LC_SYNC_ENTER_TIMER
672 clc 0(8,%r14),__LC_ASYNC_ENTER_TIMER
674 la %r14,__LC_ASYNC_ENTER_TIMER
675 0: clc 0(8,%r14),__LC_EXIT_TIMER
677 la %r14,__LC_EXIT_TIMER
678 1: clc 0(8,%r14),__LC_LAST_UPDATE_TIMER
680 la %r14,__LC_LAST_UPDATE_TIMER
682 mvc __LC_MCCK_ENTER_TIMER(8),0(%r14)
683 3: tm __LC_MCCK_CODE+2,0x09 # mwp + ia of old psw valid?
684 jno mcck_panic # no -> skip cleanup critical
685 SWITCH_ASYNC __LC_GPREGS_SAVE_AREA+64,__LC_PANIC_STACK,PAGE_SHIFT
686 tm %r8,0x0001 # interrupting from user ?
688 UPDATE_VTIME %r14,__LC_MCCK_ENTER_TIMER
691 lghi %r14,__LC_GPREGS_SAVE_AREA+64
692 stmg %r0,%r7,__PT_R0(%r11)
693 mvc __PT_R8(64,%r11),0(%r14)
694 stmg %r8,%r9,__PT_PSW(%r11)
695 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
696 lgr %r2,%r11 # pass pointer to pt_regs
697 brasl %r14,s390_do_machine_check
698 tm __PT_PSW+1(%r11),0x01 # returning to user ?
700 lg %r1,__LC_KERNEL_STACK # switch to kernel stack
701 mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
702 xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1)
703 la %r11,STACK_FRAME_OVERHEAD(%r1)
705 ssm __LC_PGM_NEW_PSW # turn dat on, keep irqs off
706 tm __TI_flags+7(%r12),_TIF_MCCK_PENDING
709 brasl %r14,s390_handle_mcck
712 lg %r14,__LC_VDSO_PER_CPU
713 lmg %r0,%r10,__PT_R0(%r11)
714 mvc __LC_RETURN_MCCK_PSW(16),__PT_PSW(%r11) # move return PSW
715 tm __LC_RETURN_MCCK_PSW+1,0x01 # returning to user ?
718 mvc __VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER
719 0: lmg %r11,%r15,__PT_R11(%r11)
720 lpswe __LC_RETURN_MCCK_PSW
723 lg %r14,__LC_PANIC_STACK
725 srag %r14,%r14,PAGE_SHIFT
727 lg %r15,__LC_PANIC_STACK
728 0: aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
732 # PSW restart interrupt handler
734 ENTRY(restart_int_handler)
735 stg %r15,__LC_SAVE_AREA_RESTART
736 lg %r15,__LC_RESTART_STACK
737 aghi %r15,-__PT_SIZE # create pt_regs on stack
738 xc 0(__PT_SIZE,%r15),0(%r15)
739 stmg %r0,%r14,__PT_R0(%r15)
740 mvc __PT_R15(8,%r15),__LC_SAVE_AREA_RESTART
741 mvc __PT_PSW(16,%r15),__LC_RST_OLD_PSW # store restart old psw
742 aghi %r15,-STACK_FRAME_OVERHEAD # create stack frame on stack
743 xc 0(STACK_FRAME_OVERHEAD,%r15),0(%r15)
744 lg %r1,__LC_RESTART_FN # load fn, parm & source cpu
745 lg %r2,__LC_RESTART_DATA
746 lg %r3,__LC_RESTART_SOURCE
747 ltgr %r3,%r3 # test source cpu address
748 jm 1f # negative -> skip source stop
749 0: sigp %r4,%r3,SIGP_SENSE # sigp sense to source cpu
750 brc 10,0b # wait for status stored
751 1: basr %r14,%r1 # call function
752 stap __SF_EMPTY(%r15) # store cpu address
753 llgh %r3,__SF_EMPTY(%r15)
754 2: sigp %r4,%r3,SIGP_STOP # sigp stop to current cpu
758 .section .kprobes.text, "ax"
760 #ifdef CONFIG_CHECK_STACK
762 * The synchronous or the asynchronous stack overflowed. We are dead.
763 * No need to properly save the registers, we are going to panic anyway.
764 * Setup a pt_regs so that show_trace can provide a good call trace.
767 lg %r15,__LC_PANIC_STACK # change to panic stack
768 la %r11,STACK_FRAME_OVERHEAD(%r15)
769 stmg %r0,%r7,__PT_R0(%r11)
770 stmg %r8,%r9,__PT_PSW(%r11)
771 mvc __PT_R8(64,%r11),0(%r14)
772 stg %r10,__PT_ORIG_GPR2(%r11) # store last break to orig_gpr2
773 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
774 lgr %r2,%r11 # pass pointer to pt_regs
775 jg kernel_stack_overflow
792 clg %r9,BASED(cleanup_table) # system_call
794 clg %r9,BASED(cleanup_table+8) # sysc_do_svc
795 jl cleanup_system_call
796 clg %r9,BASED(cleanup_table+16) # sysc_tif
798 clg %r9,BASED(cleanup_table+24) # sysc_restore
800 clg %r9,BASED(cleanup_table+32) # sysc_done
801 jl cleanup_sysc_restore
802 clg %r9,BASED(cleanup_table+40) # io_tif
804 clg %r9,BASED(cleanup_table+48) # io_restore
806 clg %r9,BASED(cleanup_table+56) # io_done
807 jl cleanup_io_restore
808 clg %r9,BASED(cleanup_table+64) # psw_idle
810 clg %r9,BASED(cleanup_table+72) # psw_idle_end
816 # check if stpt has been executed
817 clg %r9,BASED(cleanup_system_call_insn)
819 mvc __LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER
820 cghi %r11,__LC_SAVE_AREA_ASYNC
822 mvc __LC_SYNC_ENTER_TIMER(8),__LC_MCCK_ENTER_TIMER
823 0: # check if stmg has been executed
824 clg %r9,BASED(cleanup_system_call_insn+8)
826 mvc __LC_SAVE_AREA_SYNC(64),0(%r11)
827 0: # check if base register setup + TIF bit load has been done
828 clg %r9,BASED(cleanup_system_call_insn+16)
830 # set up saved registers r10 and r12
831 stg %r10,16(%r11) # r10 last break
832 stg %r12,32(%r11) # r12 thread-info pointer
833 0: # check if the user time update has been done
834 clg %r9,BASED(cleanup_system_call_insn+24)
836 lg %r15,__LC_EXIT_TIMER
837 slg %r15,__LC_SYNC_ENTER_TIMER
838 alg %r15,__LC_USER_TIMER
839 stg %r15,__LC_USER_TIMER
840 0: # check if the system time update has been done
841 clg %r9,BASED(cleanup_system_call_insn+32)
843 lg %r15,__LC_LAST_UPDATE_TIMER
844 slg %r15,__LC_EXIT_TIMER
845 alg %r15,__LC_SYSTEM_TIMER
846 stg %r15,__LC_SYSTEM_TIMER
847 0: # update accounting time stamp
848 mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
853 mvc __TI_last_break(8,%r12),16(%r11)
854 0: # set up saved register r11
855 lg %r15,__LC_KERNEL_STACK
856 la %r9,STACK_FRAME_OVERHEAD(%r15)
857 stg %r9,24(%r11) # r11 pt_regs pointer
859 mvc __PT_R8(64,%r9),__LC_SAVE_AREA_SYNC
860 stmg %r0,%r7,__PT_R0(%r9)
861 mvc __PT_PSW(16,%r9),__LC_SVC_OLD_PSW
862 mvc __PT_INT_CODE(4,%r9),__LC_SVC_ILC
863 # setup saved register r15
864 stg %r15,56(%r11) # r15 stack pointer
865 # set new psw address and exit
868 cleanup_system_call_insn:
879 cleanup_sysc_restore:
880 clg %r9,BASED(cleanup_sysc_restore_insn)
882 lg %r9,24(%r11) # get saved pointer to pt_regs
883 mvc __LC_RETURN_PSW(16),__PT_PSW(%r9)
884 mvc 0(64,%r11),__PT_R8(%r9)
885 lmg %r0,%r7,__PT_R0(%r9)
886 0: lmg %r8,%r9,__LC_RETURN_PSW
888 cleanup_sysc_restore_insn:
896 clg %r9,BASED(cleanup_io_restore_insn)
898 lg %r9,24(%r11) # get saved r11 pointer to pt_regs
899 mvc __LC_RETURN_PSW(16),__PT_PSW(%r9)
900 mvc 0(64,%r11),__PT_R8(%r9)
901 lmg %r0,%r7,__PT_R0(%r9)
902 0: lmg %r8,%r9,__LC_RETURN_PSW
904 cleanup_io_restore_insn:
908 # copy interrupt clock & cpu timer
909 mvc __CLOCK_IDLE_EXIT(8,%r2),__LC_INT_CLOCK
910 mvc __TIMER_IDLE_EXIT(8,%r2),__LC_ASYNC_ENTER_TIMER
911 cghi %r11,__LC_SAVE_AREA_ASYNC
913 mvc __CLOCK_IDLE_EXIT(8,%r2),__LC_MCCK_CLOCK
914 mvc __TIMER_IDLE_EXIT(8,%r2),__LC_MCCK_ENTER_TIMER
915 0: # check if stck & stpt have been executed
916 clg %r9,BASED(cleanup_idle_insn)
918 mvc __CLOCK_IDLE_ENTER(8,%r2),__CLOCK_IDLE_EXIT(%r2)
919 mvc __TIMER_IDLE_ENTER(8,%r2),__TIMER_IDLE_EXIT(%r2)
920 1: # account system time going idle
921 lg %r9,__LC_STEAL_TIMER
922 alg %r9,__CLOCK_IDLE_ENTER(%r2)
923 slg %r9,__LC_LAST_UPDATE_CLOCK
924 stg %r9,__LC_STEAL_TIMER
925 mvc __LC_LAST_UPDATE_CLOCK(8),__CLOCK_IDLE_EXIT(%r2)
926 lg %r9,__LC_SYSTEM_TIMER
927 alg %r9,__LC_LAST_UPDATE_TIMER
928 slg %r9,__TIMER_IDLE_ENTER(%r2)
929 stg %r9,__LC_SYSTEM_TIMER
930 mvc __LC_LAST_UPDATE_TIMER(8),__TIMER_IDLE_EXIT(%r2)
932 nihh %r8,0xfcfd # clear irq & wait state bits
933 lg %r9,48(%r11) # return from psw_idle
943 .quad __critical_start
945 .quad __critical_end - __critical_start
948 #if defined(CONFIG_KVM) || defined(CONFIG_KVM_MODULE)
950 * sie64a calling convention:
951 * %r2 pointer to sie control block
952 * %r3 guest register save area
955 stmg %r6,%r14,__SF_GPRS(%r15) # save kernel registers
956 stg %r2,__SF_EMPTY(%r15) # save control block pointer
957 stg %r3,__SF_EMPTY+8(%r15) # save guest register save area
958 xc __SF_EMPTY+16(16,%r15),__SF_EMPTY+16(%r15) # host id & reason
959 lmg %r0,%r13,0(%r3) # load guest gprs 0-13
960 lg %r14,__LC_GMAP # get gmap pointer
963 lctlg %c1,%c1,__GMAP_ASCE(%r14) # load primary asce
965 lg %r14,__SF_EMPTY(%r15) # get control block pointer
966 oi __SIE_PROG0C+3(%r14),1 # we are going into SIE now
967 tm __SIE_PROG20+3(%r14),1 # last exit...
969 LPP __SF_EMPTY(%r15) # set guest id
972 LPP __SF_EMPTY+16(%r15) # set host id
973 ni __SIE_PROG0C+3(%r14),0xfe # no longer in SIE
974 lctlg %c1,%c1,__LC_USER_ASCE # load primary asce
975 # some program checks are suppressing. C code (e.g. do_protection_exception)
976 # will rewind the PSW by the ILC, which is 4 bytes in case of SIE. Other
977 # instructions beween sie64a and sie_done should not cause program
978 # interrupts. So lets use a nop (47 00 00 00) as a landing pad.
979 # See also HANDLE_SIE_INTERCEPT
984 lg %r14,__SF_EMPTY+8(%r15) # load guest register save area
985 stmg %r0,%r13,0(%r14) # save guest gprs 0-13
986 lmg %r6,%r14,__SF_GPRS(%r15) # restore kernel registers
987 lg %r2,__SF_EMPTY+24(%r15) # return exit reason code
991 stg %r14,__SF_EMPTY+24(%r15) # set exit reason code
997 .Lsie_critical_length:
998 .quad sie_done - sie_gmap
1000 EX_TABLE(rewind_pad,sie_fault)
1001 EX_TABLE(sie_exit,sie_fault)
1004 .section .rodata, "a"
1005 #define SYSCALL(esa,esame,emu) .long esame
1006 .globl sys_call_table
1008 #include "syscalls.S"
1011 #ifdef CONFIG_COMPAT
1013 #define SYSCALL(esa,esame,emu) .long emu
1014 .globl sys_call_table_emu
1016 #include "syscalls.S"