2 * arch/s390/kernel/entry64.S
3 * S390 low-level entry points.
5 * Copyright (C) IBM Corp. 1999,2006
6 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
7 * Hartmut Penner (hp@de.ibm.com),
8 * Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
9 * Heiko Carstens <heiko.carstens@de.ibm.com>
12 #include <linux/sys.h>
13 #include <linux/linkage.h>
14 #include <asm/cache.h>
15 #include <asm/lowcore.h>
16 #include <asm/errno.h>
17 #include <asm/ptrace.h>
18 #include <asm/thread_info.h>
19 #include <asm/asm-offsets.h>
20 #include <asm/unistd.h>
24 * Stack layout for the system_call stack entry.
25 * The first few entries are identical to the user_regs_struct.
27 SP_PTREGS = STACK_FRAME_OVERHEAD
28 SP_ARGS = STACK_FRAME_OVERHEAD + __PT_ARGS
29 SP_PSW = STACK_FRAME_OVERHEAD + __PT_PSW
30 SP_R0 = STACK_FRAME_OVERHEAD + __PT_GPRS
31 SP_R1 = STACK_FRAME_OVERHEAD + __PT_GPRS + 8
32 SP_R2 = STACK_FRAME_OVERHEAD + __PT_GPRS + 16
33 SP_R3 = STACK_FRAME_OVERHEAD + __PT_GPRS + 24
34 SP_R4 = STACK_FRAME_OVERHEAD + __PT_GPRS + 32
35 SP_R5 = STACK_FRAME_OVERHEAD + __PT_GPRS + 40
36 SP_R6 = STACK_FRAME_OVERHEAD + __PT_GPRS + 48
37 SP_R7 = STACK_FRAME_OVERHEAD + __PT_GPRS + 56
38 SP_R8 = STACK_FRAME_OVERHEAD + __PT_GPRS + 64
39 SP_R9 = STACK_FRAME_OVERHEAD + __PT_GPRS + 72
40 SP_R10 = STACK_FRAME_OVERHEAD + __PT_GPRS + 80
41 SP_R11 = STACK_FRAME_OVERHEAD + __PT_GPRS + 88
42 SP_R12 = STACK_FRAME_OVERHEAD + __PT_GPRS + 96
43 SP_R13 = STACK_FRAME_OVERHEAD + __PT_GPRS + 104
44 SP_R14 = STACK_FRAME_OVERHEAD + __PT_GPRS + 112
45 SP_R15 = STACK_FRAME_OVERHEAD + __PT_GPRS + 120
46 SP_ORIG_R2 = STACK_FRAME_OVERHEAD + __PT_ORIG_GPR2
47 SP_ILC = STACK_FRAME_OVERHEAD + __PT_ILC
48 SP_TRAP = STACK_FRAME_OVERHEAD + __PT_TRAP
49 SP_SIZE = STACK_FRAME_OVERHEAD + __PT_SIZE
51 STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
52 STACK_SIZE = 1 << STACK_SHIFT
54 _TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK | _TIF_NEED_RESCHED | \
55 _TIF_MCCK_PENDING | _TIF_RESTART_SVC | _TIF_SINGLE_STEP )
56 _TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK | _TIF_NEED_RESCHED | \
59 #define BASED(name) name-system_call(%r13)
61 #ifdef CONFIG_TRACE_IRQFLAGS
63 brasl %r14,trace_hardirqs_on
67 brasl %r14,trace_hardirqs_off
71 #define TRACE_IRQS_OFF
74 .macro STORE_TIMER lc_offset
75 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
80 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
81 .macro UPDATE_VTIME lc_from,lc_to,lc_sum
90 * Register usage in interrupt handlers:
91 * R9 - pointer to current task structure
92 * R13 - pointer to literal pool
93 * R14 - return register for function calls
94 * R15 - kernel stack pointer
97 .macro SAVE_ALL_BASE savearea
98 stmg %r12,%r15,\savearea
102 .macro SAVE_ALL_SVC psworg,savearea
104 lg %r15,__LC_KERNEL_STACK # problem state -> load ksp
107 .macro SAVE_ALL_SYNC psworg,savearea
109 tm \psworg+1,0x01 # test problem state bit
110 jz 2f # skip stack setup save
111 lg %r15,__LC_KERNEL_STACK # problem state -> load ksp
112 #ifdef CONFIG_CHECK_STACK
114 2: tml %r15,STACK_SIZE - CONFIG_STACK_GUARD
121 .macro SAVE_ALL_ASYNC psworg,savearea
123 tm \psworg+1,0x01 # test problem state bit
124 jnz 1f # from user -> load kernel stack
125 clc \psworg+8(8),BASED(.Lcritical_end)
127 clc \psworg+8(8),BASED(.Lcritical_start)
129 brasl %r14,cleanup_critical
130 tm 1(%r12),0x01 # retest problem state after cleanup
132 0: lg %r14,__LC_ASYNC_STACK # are we already on the async. stack ?
134 srag %r14,%r14,STACK_SHIFT
136 1: lg %r15,__LC_ASYNC_STACK # load async stack
137 #ifdef CONFIG_CHECK_STACK
139 2: tml %r15,STACK_SIZE - CONFIG_STACK_GUARD
146 .macro CREATE_STACK_FRAME psworg,savearea
147 aghi %r15,-SP_SIZE # make room for registers & psw
148 mvc SP_PSW(16,%r15),0(%r12) # move user PSW to stack
150 stg %r2,SP_ORIG_R2(%r15) # store original content of gpr 2
151 icm %r12,12,__LC_SVC_ILC
152 stmg %r0,%r11,SP_R0(%r15) # store gprs %r0-%r11 to kernel stack
154 mvc SP_R12(32,%r15),\savearea # move %r12-%r15 to stack
156 stg %r12,__SF_BACKCHAIN(%r15)
159 .macro RESTORE_ALL psworg,sync
160 mvc \psworg(16),SP_PSW(%r15) # move user PSW to lowcore
162 ni \psworg+1,0xfd # clear wait state bit
164 lmg %r0,%r15,SP_R0(%r15) # load gprs 0-15 of user
165 STORE_TIMER __LC_EXIT_TIMER
166 lpswe \psworg # back to caller
170 * Scheduler resume function, called by switch_to
171 * gpr2 = (task_struct *) prev
172 * gpr3 = (task_struct *) next
178 tm __THREAD_per+4(%r3),0xe8 # is the new process using per ?
179 jz __switch_to_noper # if not we're fine
180 stctg %c9,%c11,__SF_EMPTY(%r15)# We are using per stuff
181 clc __THREAD_per(24,%r3),__SF_EMPTY(%r15)
182 je __switch_to_noper # we got away without bashing TLB's
183 lctlg %c9,%c11,__THREAD_per(%r3) # Nope we didn't
185 lg %r4,__THREAD_info(%r2) # get thread_info of prev
186 tm __TI_flags+7(%r4),_TIF_MCCK_PENDING # machine check pending?
187 jz __switch_to_no_mcck
188 ni __TI_flags+7(%r4),255-_TIF_MCCK_PENDING # clear flag in prev
189 lg %r4,__THREAD_info(%r3) # get thread_info of next
190 oi __TI_flags+7(%r4),_TIF_MCCK_PENDING # set it in next
192 stmg %r6,%r15,__SF_GPRS(%r15)# store __switch_to registers of prev task
193 stg %r15,__THREAD_ksp(%r2) # store kernel stack to prev->tss.ksp
194 lg %r15,__THREAD_ksp(%r3) # load kernel stack from next->tss.ksp
195 lmg %r6,%r15,__SF_GPRS(%r15)# load __switch_to registers of next task
196 stg %r3,__LC_CURRENT # __LC_CURRENT = current task struct
197 lctl %c4,%c4,__TASK_pid(%r3) # load pid to control reg. 4
198 lg %r3,__THREAD_info(%r3) # load thread_info from task struct
199 stg %r3,__LC_THREAD_INFO
201 stg %r3,__LC_KERNEL_STACK # __LC_KERNEL_STACK = new kernel stack
206 * SVC interrupt handler routine. System calls are synchronous events and
207 * are executed with interrupts enabled.
212 STORE_TIMER __LC_SYNC_ENTER_TIMER
214 SAVE_ALL_BASE __LC_SAVE_AREA
215 SAVE_ALL_SVC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
216 CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
217 llgh %r7,__LC_SVC_INT_CODE # get svc number from lowcore
218 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
220 tm SP_PSW+1(%r15),0x01 # interrupting from user ?
222 UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
224 UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
226 mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
229 lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
230 slag %r7,%r7,2 # *4 and test for svc 0
232 # svc 0: system call number in %r1
233 cl %r1,BASED(.Lnr_syscalls)
235 lgfr %r7,%r1 # clear high word in r1
236 slag %r7,%r7,2 # svc 0: system call number in %r1
238 mvc SP_ARGS(8,%r15),SP_R7(%r15)
240 larl %r10,sys_call_table
242 tm __TI_flags+5(%r9),(_TIF_31BIT>>16) # running in 31 bit mode ?
244 larl %r10,sys_call_table_emu # use 31 bit emulation system calls
247 tm __TI_flags+7(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
248 lgf %r8,0(%r7,%r10) # load address of system call routine
250 basr %r14,%r8 # call sys_xxxx
251 stg %r2,SP_R2(%r15) # store return value (change R2 on stack)
254 tm SP_PSW+1(%r15),0x01 # returning to user ?
256 tm __TI_flags+7(%r9),_TIF_WORK_SVC
257 jnz sysc_work # there is work to do (signals etc.)
259 RESTORE_ALL __LC_RETURN_PSW,1
262 # recheck if there is more work to do
265 tm __TI_flags+7(%r9),_TIF_WORK_SVC
266 jz sysc_leave # there is no work to do
268 # One of the work bits is on. Find out which one.
271 tm __TI_flags+7(%r9),_TIF_MCCK_PENDING
273 tm __TI_flags+7(%r9),_TIF_NEED_RESCHED
275 tm __TI_flags+7(%r9),(_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK)
277 tm __TI_flags+7(%r9),_TIF_RESTART_SVC
279 tm __TI_flags+7(%r9),_TIF_SINGLE_STEP
284 # _TIF_NEED_RESCHED is set, call schedule
287 larl %r14,sysc_work_loop
288 jg schedule # return point is sysc_return
291 # _TIF_MCCK_PENDING is set, call handler
294 larl %r14,sysc_work_loop
295 jg s390_handle_mcck # TIF bit will be cleared by handler
298 # _TIF_SIGPENDING or _TIF_RESTORE_SIGMASK is set, call do_signal
301 ni __TI_flags+7(%r9),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
302 la %r2,SP_PTREGS(%r15) # load pt_regs
303 brasl %r14,do_signal # call do_signal
304 tm __TI_flags+7(%r9),_TIF_RESTART_SVC
306 tm __TI_flags+7(%r9),_TIF_SINGLE_STEP
311 # _TIF_RESTART_SVC is set, set up registers and restart svc
314 ni __TI_flags+7(%r9),255-_TIF_RESTART_SVC # clear TIF_RESTART_SVC
315 lg %r7,SP_R2(%r15) # load new svc number
317 mvc SP_R2(8,%r15),SP_ORIG_R2(%r15) # restore first argument
318 lmg %r2,%r6,SP_R2(%r15) # load svc arguments
319 j sysc_do_restart # restart svc
322 # _TIF_SINGLE_STEP is set, call do_single_step
325 ni __TI_flags+7(%r9),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
326 lhi %r0,__LC_PGM_OLD_PSW
327 sth %r0,SP_TRAP(%r15) # set trap indication to pgm check
328 la %r2,SP_PTREGS(%r15) # address of register-save area
329 larl %r14,sysc_return # load adr. of system return
330 jg do_single_step # branch to do_sigtrap
333 # call syscall_trace before and after system call
334 # special linkage: %r12 contains the return address for trace_svc
337 la %r2,SP_PTREGS(%r15) # load pt_regs
341 brasl %r14,syscall_trace
345 lg %r7,SP_R2(%r15) # strace might have changed the
346 sll %r7,2 # system call
349 lmg %r3,%r6,SP_R3(%r15)
350 lg %r2,SP_ORIG_R2(%r15)
351 basr %r14,%r8 # call sys_xxx
352 stg %r2,SP_R2(%r15) # store return value
354 tm __TI_flags+7(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
356 la %r2,SP_PTREGS(%r15) # load pt_regs
358 larl %r14,sysc_return # return point is sysc_return
362 # a new process exits the kernel with ret_from_fork
366 lg %r13,__LC_SVC_NEW_PSW+8
367 lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
368 tm SP_PSW+1(%r15),0x01 # forking a kernel thread ?
370 stg %r15,SP_R15(%r15) # store stack pointer for new kthread
371 0: brasl %r14,schedule_tail
373 stosm 24(%r15),0x03 # reenable interrupts
377 # kernel_execve function needs to deal with pt_regs that is not
382 stmg %r12,%r15,96(%r15)
385 stg %r14,__SF_BACKCHAIN(%r15)
386 la %r12,SP_PTREGS(%r15)
387 xc 0(__PT_SIZE,%r12),0(%r12)
393 lmg %r12,%r15,96(%r15)
396 0: stnsm __SF_EMPTY(%r15),0xfc # disable interrupts
397 lg %r15,__LC_KERNEL_STACK # load ksp
398 aghi %r15,-SP_SIZE # make room for registers & psw
399 lg %r13,__LC_SVC_NEW_PSW+8
400 lg %r9,__LC_THREAD_INFO
401 mvc SP_PTREGS(__PT_SIZE,%r15),0(%r12) # copy pt_regs
402 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
403 stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
404 brasl %r14,execve_tail
408 * Program check handler routine
411 .globl pgm_check_handler
414 * First we need to check for a special case:
415 * Single stepping an instruction that disables the PER event mask will
416 * cause a PER event AFTER the mask has been set. Example: SVC or LPSW.
417 * For a single stepped SVC the program check handler gets control after
418 * the SVC new PSW has been loaded. But we want to execute the SVC first and
419 * then handle the PER event. Therefore we update the SVC old PSW to point
420 * to the pgm_check_handler and branch to the SVC handler after we checked
421 * if we have to load the kernel stack register.
422 * For every other possible cause for PER event without the PER mask set
423 * we just ignore the PER event (FIXME: is there anything we have to do
426 STORE_TIMER __LC_SYNC_ENTER_TIMER
427 SAVE_ALL_BASE __LC_SAVE_AREA
428 tm __LC_PGM_INT_CODE+1,0x80 # check whether we got a per exception
429 jnz pgm_per # got per exception -> special case
430 SAVE_ALL_SYNC __LC_PGM_OLD_PSW,__LC_SAVE_AREA
431 CREATE_STACK_FRAME __LC_PGM_OLD_PSW,__LC_SAVE_AREA
432 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
433 tm SP_PSW+1(%r15),0x01 # interrupting from user ?
435 UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
436 UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
437 mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
440 lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
441 lgf %r3,__LC_PGM_ILC # load program interruption code
446 larl %r1,pgm_check_table
447 lg %r1,0(%r8,%r1) # load address of handler routine
448 la %r2,SP_PTREGS(%r15) # address of register-save area
449 larl %r14,sysc_return
450 br %r1 # branch to interrupt-handler
453 # handle per exception
456 tm __LC_PGM_OLD_PSW,0x40 # test if per event recording is on
457 jnz pgm_per_std # ok, normal per event from user space
458 # ok its one of the special cases, now we need to find out which one
459 clc __LC_PGM_OLD_PSW(16),__LC_SVC_NEW_PSW
461 # no interesting special case, ignore PER event
462 lmg %r12,%r15,__LC_SAVE_AREA
463 lpswe __LC_PGM_OLD_PSW
466 # Normal per exception
469 SAVE_ALL_SYNC __LC_PGM_OLD_PSW,__LC_SAVE_AREA
470 CREATE_STACK_FRAME __LC_PGM_OLD_PSW,__LC_SAVE_AREA
471 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
472 tm SP_PSW+1(%r15),0x01 # interrupting from user ?
474 UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
475 UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
476 mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
479 lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
480 lg %r1,__TI_task(%r9)
481 tm SP_PSW+1(%r15),0x01 # kernel per event ?
483 mvc __THREAD_per+__PER_atmid(2,%r1),__LC_PER_ATMID
484 mvc __THREAD_per+__PER_address(8,%r1),__LC_PER_ADDRESS
485 mvc __THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID
486 oi __TI_flags+7(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
487 lgf %r3,__LC_PGM_ILC # load program interruption code
489 ngr %r8,%r3 # clear per-event-bit and ilc
494 # it was a single stepped SVC that is causing all the trouble
497 SAVE_ALL_SYNC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
498 CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
499 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
500 tm SP_PSW+1(%r15),0x01 # interrupting from user ?
502 UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
503 UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
504 mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
507 llgh %r7,__LC_SVC_INT_CODE # get svc number from lowcore
508 lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
509 lg %r1,__TI_task(%r9)
510 mvc __THREAD_per+__PER_atmid(2,%r1),__LC_PER_ATMID
511 mvc __THREAD_per+__PER_address(8,%r1),__LC_PER_ADDRESS
512 mvc __THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID
513 oi __TI_flags+7(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
515 stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
519 # per was called from kernel, must be kprobes
522 lhi %r0,__LC_PGM_OLD_PSW
523 sth %r0,SP_TRAP(%r15) # set trap indication to pgm check
524 la %r2,SP_PTREGS(%r15) # address of register-save area
525 larl %r14,sysc_leave # load adr. of system ret, no work
526 jg do_single_step # branch to do_single_step
529 * IO interrupt handler routine
531 .globl io_int_handler
533 STORE_TIMER __LC_ASYNC_ENTER_TIMER
535 SAVE_ALL_BASE __LC_SAVE_AREA+32
536 SAVE_ALL_ASYNC __LC_IO_OLD_PSW,__LC_SAVE_AREA+32
537 CREATE_STACK_FRAME __LC_IO_OLD_PSW,__LC_SAVE_AREA+32
538 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
539 tm SP_PSW+1(%r15),0x01 # interrupting from user ?
541 UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
542 UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
543 mvc __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
546 lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
548 la %r2,SP_PTREGS(%r15) # address of register-save area
549 brasl %r14,do_IRQ # call standard irq handler
553 tm SP_PSW+1(%r15),0x01 # returning to user ?
554 #ifdef CONFIG_PREEMPT
555 jno io_preempt # no -> check for preemptive scheduling
557 jno io_leave # no-> skip resched & signal
559 tm __TI_flags+7(%r9),_TIF_WORK_INT
560 jnz io_work # there is work to do (signals etc.)
562 RESTORE_ALL __LC_RETURN_PSW,0
565 #ifdef CONFIG_PREEMPT
567 icm %r0,15,__TI_precount(%r9)
569 # switch to kernel stack
572 mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
573 xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1) # clear back chain
576 tm __TI_flags+7(%r9),_TIF_NEED_RESCHED
579 mvc __TI_precount(4,%r9),0(%r1)
580 stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
581 brasl %r14,schedule # call schedule
582 stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
583 xc __TI_precount(4,%r9),__TI_precount(%r9)
588 # switch to kernel stack, then check TIF bits
591 lg %r1,__LC_KERNEL_STACK
593 mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
594 xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1) # clear back chain
597 # One of the work bits is on. Find out which one.
598 # Checked are: _TIF_SIGPENDING, _TIF_RESTORE_SIGPENDING, _TIF_NEED_RESCHED
599 # and _TIF_MCCK_PENDING
602 tm __TI_flags+7(%r9),_TIF_MCCK_PENDING
604 tm __TI_flags+7(%r9),_TIF_NEED_RESCHED
606 tm __TI_flags+7(%r9),(_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK)
611 # _TIF_MCCK_PENDING is set, call handler
615 brasl %r14,s390_handle_mcck # TIF bit will be cleared by handler
620 # _TIF_NEED_RESCHED is set, call schedule
623 stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
624 brasl %r14,schedule # call scheduler
625 stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
626 tm __TI_flags+7(%r9),_TIF_WORK_INT
627 jz io_leave # there is no work to do
631 # _TIF_SIGPENDING or _TIF_RESTORE_SIGMASK is set, call do_signal
634 stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
635 la %r2,SP_PTREGS(%r15) # load pt_regs
636 brasl %r14,do_signal # call do_signal
637 stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
641 * External interrupt handler routine
643 .globl ext_int_handler
645 STORE_TIMER __LC_ASYNC_ENTER_TIMER
647 SAVE_ALL_BASE __LC_SAVE_AREA+32
648 SAVE_ALL_ASYNC __LC_EXT_OLD_PSW,__LC_SAVE_AREA+32
649 CREATE_STACK_FRAME __LC_EXT_OLD_PSW,__LC_SAVE_AREA+32
650 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
651 tm SP_PSW+1(%r15),0x01 # interrupting from user ?
653 UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
654 UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
655 mvc __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
658 lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
660 la %r2,SP_PTREGS(%r15) # address of register-save area
661 llgh %r3,__LC_EXT_INT_CODE # get interruption code
669 * Machine check handler routines
671 .globl mcck_int_handler
673 la %r1,4095 # revalidate r1
674 spt __LC_CPU_TIMER_SAVE_AREA-4095(%r1) # revalidate cpu timer
675 lmg %r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r1)# revalidate gprs
676 SAVE_ALL_BASE __LC_SAVE_AREA+64
677 la %r12,__LC_MCK_OLD_PSW
678 tm __LC_MCCK_CODE,0x80 # system damage?
679 jo mcck_int_main # yes -> rest of mcck code invalid
680 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
682 mvc __LC_SAVE_AREA+104(8),__LC_ASYNC_ENTER_TIMER
683 mvc __LC_ASYNC_ENTER_TIMER(8),__LC_CPU_TIMER_SAVE_AREA-4095(%r14)
684 tm __LC_MCCK_CODE+5,0x02 # stored cpu timer value valid?
686 la %r14,__LC_SYNC_ENTER_TIMER
687 clc 0(8,%r14),__LC_ASYNC_ENTER_TIMER
689 la %r14,__LC_ASYNC_ENTER_TIMER
690 0: clc 0(8,%r14),__LC_EXIT_TIMER
692 la %r14,__LC_EXIT_TIMER
693 0: clc 0(8,%r14),__LC_LAST_UPDATE_TIMER
695 la %r14,__LC_LAST_UPDATE_TIMER
697 mvc __LC_ASYNC_ENTER_TIMER(8),0(%r14)
700 tm __LC_MCCK_CODE+2,0x09 # mwp + ia of old psw valid?
701 jno mcck_int_main # no -> skip cleanup critical
702 tm __LC_MCK_OLD_PSW+1,0x01 # test problem state bit
703 jnz mcck_int_main # from user -> load kernel stack
704 clc __LC_MCK_OLD_PSW+8(8),BASED(.Lcritical_end)
706 clc __LC_MCK_OLD_PSW+8(8),BASED(.Lcritical_start)
708 brasl %r14,cleanup_critical
710 lg %r14,__LC_PANIC_STACK # are we already on the panic stack?
712 srag %r14,%r14,PAGE_SHIFT
714 lg %r15,__LC_PANIC_STACK # load panic stack
715 0: CREATE_STACK_FRAME __LC_MCK_OLD_PSW,__LC_SAVE_AREA+64
716 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
717 tm __LC_MCCK_CODE+2,0x08 # mwp of old psw valid?
718 jno mcck_no_vtime # no -> no timer update
719 tm SP_PSW+1(%r15),0x01 # interrupting from user ?
721 UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
722 UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
723 mvc __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
726 lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
727 la %r2,SP_PTREGS(%r15) # load pt_regs
728 brasl %r14,s390_do_machine_check
729 tm SP_PSW+1(%r15),0x01 # returning to user ?
731 lg %r1,__LC_KERNEL_STACK # switch to kernel stack
733 mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
734 xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1) # clear back chain
736 stosm __SF_EMPTY(%r15),0x04 # turn dat on
737 tm __TI_flags+7(%r9),_TIF_MCCK_PENDING
740 brasl %r14,s390_handle_mcck
743 mvc __LC_RETURN_MCCK_PSW(16),SP_PSW(%r15) # move return PSW
744 ni __LC_RETURN_MCCK_PSW+1,0xfd # clear wait state bit
745 lmg %r0,%r15,SP_R0(%r15) # load gprs 0-15
746 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
747 mvc __LC_ASYNC_ENTER_TIMER(8),__LC_SAVE_AREA+104
748 tm __LC_RETURN_MCCK_PSW+1,0x01 # returning to user ?
753 lpswe __LC_RETURN_MCCK_PSW # back to caller
756 * Restart interruption handler, kick starter for additional CPUs
759 #ifndef CONFIG_HOTPLUG_CPU
760 .section .init.text,"ax"
762 .globl restart_int_handler
764 lg %r15,__LC_SAVE_AREA+120 # load ksp
765 lghi %r10,__LC_CREGS_SAVE_AREA
766 lctlg %c0,%c15,0(%r10) # get new ctl regs
767 lghi %r10,__LC_AREGS_SAVE_AREA
769 lmg %r6,%r15,__SF_GPRS(%r15) # load registers from clone
770 stosm __SF_EMPTY(%r15),0x04 # now we can turn dat on
772 #ifndef CONFIG_HOTPLUG_CPU
777 * If we do not run with SMP enabled, let the new CPU crash ...
779 .globl restart_int_handler
783 lpswe restart_crash-restart_base(%r1)
786 .long 0x000a0000,0x00000000,0x00000000,0x00000000
790 #ifdef CONFIG_CHECK_STACK
792 * The synchronous or the asynchronous stack overflowed. We are dead.
793 * No need to properly save the registers, we are going to panic anyway.
794 * Setup a pt_regs so that show_trace can provide a good call trace.
797 lg %r15,__LC_PANIC_STACK # change to panic stack
799 mvc SP_PSW(16,%r15),0(%r12) # move user PSW to stack
800 stmg %r0,%r11,SP_R0(%r15) # store gprs %r0-%r11 to kernel stack
801 la %r1,__LC_SAVE_AREA
802 chi %r12,__LC_SVC_OLD_PSW
804 chi %r12,__LC_PGM_OLD_PSW
806 la %r1,__LC_SAVE_AREA+32
807 0: mvc SP_R12(32,%r15),0(%r1) # move %r12-%r15 to stack
808 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) # clear back chain
809 la %r2,SP_PTREGS(%r15) # load pt_regs
810 jg kernel_stack_overflow
813 cleanup_table_system_call:
814 .quad system_call, sysc_do_svc
815 cleanup_table_sysc_return:
816 .quad sysc_return, sysc_leave
817 cleanup_table_sysc_leave:
818 .quad sysc_leave, sysc_work_loop
819 cleanup_table_sysc_work_loop:
820 .quad sysc_work_loop, sysc_reschedule
821 cleanup_table_io_return:
822 .quad io_return, io_leave
823 cleanup_table_io_leave:
824 .quad io_leave, io_done
825 cleanup_table_io_work_loop:
826 .quad io_work_loop, io_mcck_pending
829 clc 8(8,%r12),BASED(cleanup_table_system_call)
831 clc 8(8,%r12),BASED(cleanup_table_system_call+8)
832 jl cleanup_system_call
834 clc 8(8,%r12),BASED(cleanup_table_sysc_return)
836 clc 8(8,%r12),BASED(cleanup_table_sysc_return+8)
837 jl cleanup_sysc_return
839 clc 8(8,%r12),BASED(cleanup_table_sysc_leave)
841 clc 8(8,%r12),BASED(cleanup_table_sysc_leave+8)
842 jl cleanup_sysc_leave
844 clc 8(8,%r12),BASED(cleanup_table_sysc_work_loop)
846 clc 8(8,%r12),BASED(cleanup_table_sysc_work_loop+8)
847 jl cleanup_sysc_return
849 clc 8(8,%r12),BASED(cleanup_table_io_return)
851 clc 8(8,%r12),BASED(cleanup_table_io_return+8)
854 clc 8(8,%r12),BASED(cleanup_table_io_leave)
856 clc 8(8,%r12),BASED(cleanup_table_io_leave+8)
859 clc 8(8,%r12),BASED(cleanup_table_io_work_loop)
861 clc 8(8,%r12),BASED(cleanup_table_io_work_loop+8)
867 mvc __LC_RETURN_PSW(16),0(%r12)
868 cghi %r12,__LC_MCK_OLD_PSW
870 la %r12,__LC_SAVE_AREA+32
872 0: la %r12,__LC_SAVE_AREA+64
874 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
875 clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn+8)
877 mvc __LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER
878 0: clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn+16)
881 clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn)
883 mvc __LC_SAVE_AREA(32),0(%r12)
885 stg %r12,__LC_SAVE_AREA+96 # argh
886 SAVE_ALL_SYNC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
887 CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
888 lg %r12,__LC_SAVE_AREA+96 # argh
890 llgh %r7,__LC_SVC_INT_CODE
891 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
893 clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn+24)
895 tm SP_PSW+1(%r15),0x01 # interrupting from user ?
897 UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
899 clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn+32)
901 UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
903 mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
906 mvc __LC_RETURN_PSW+8(8),BASED(cleanup_table_system_call+8)
907 la %r12,__LC_RETURN_PSW
909 cleanup_system_call_insn:
911 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
919 mvc __LC_RETURN_PSW(8),0(%r12)
920 mvc __LC_RETURN_PSW+8(8),BASED(cleanup_table_sysc_return)
921 la %r12,__LC_RETURN_PSW
925 clc 8(8,%r12),BASED(cleanup_sysc_leave_insn)
927 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
928 mvc __LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER
929 clc 8(8,%r12),BASED(cleanup_sysc_leave_insn+8)
932 mvc __LC_RETURN_PSW(16),SP_PSW(%r15)
933 cghi %r12,__LC_MCK_OLD_PSW
935 mvc __LC_SAVE_AREA+64(32),SP_R12(%r15)
937 0: mvc __LC_SAVE_AREA+32(32),SP_R12(%r15)
938 1: lmg %r0,%r11,SP_R0(%r15)
940 2: la %r12,__LC_RETURN_PSW
942 cleanup_sysc_leave_insn:
943 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
944 .quad sysc_leave + 16
946 .quad sysc_leave + 12
949 mvc __LC_RETURN_PSW(8),0(%r12)
950 mvc __LC_RETURN_PSW+8(8),BASED(cleanup_table_io_work_loop)
951 la %r12,__LC_RETURN_PSW
955 clc 8(8,%r12),BASED(cleanup_io_leave_insn)
957 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
958 mvc __LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER
959 clc 8(8,%r12),BASED(cleanup_io_leave_insn+8)
962 mvc __LC_RETURN_PSW(16),SP_PSW(%r15)
963 cghi %r12,__LC_MCK_OLD_PSW
965 mvc __LC_SAVE_AREA+64(32),SP_R12(%r15)
967 0: mvc __LC_SAVE_AREA+32(32),SP_R12(%r15)
968 1: lmg %r0,%r11,SP_R0(%r15)
970 2: la %r12,__LC_RETURN_PSW
972 cleanup_io_leave_insn:
973 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
983 .Lc_pactive: .long PREEMPT_ACTIVE
984 .Lnr_syscalls: .long NR_syscalls
985 .L0x0130: .short 0x130
986 .L0x0140: .short 0x140
987 .L0x0150: .short 0x150
988 .L0x0160: .short 0x160
989 .L0x0170: .short 0x170
991 .quad __critical_start
995 .section .rodata, "a"
996 #define SYSCALL(esa,esame,emu) .long esame
998 #include "syscalls.S"
1001 #ifdef CONFIG_COMPAT
1003 #define SYSCALL(esa,esame,emu) .long emu
1005 #include "syscalls.S"