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_SYNC psworg,savearea
104 tm \psworg+1,0x01 # test problem state bit
105 jz 2f # skip stack setup save
106 lg %r15,__LC_KERNEL_STACK # problem state -> load ksp
107 #ifdef CONFIG_CHECK_STACK
109 2: tml %r15,STACK_SIZE - CONFIG_STACK_GUARD
116 .macro SAVE_ALL_ASYNC psworg,savearea
118 tm \psworg+1,0x01 # test problem state bit
119 jnz 1f # from user -> load kernel stack
120 clc \psworg+8(8),BASED(.Lcritical_end)
122 clc \psworg+8(8),BASED(.Lcritical_start)
124 brasl %r14,cleanup_critical
125 tm 1(%r12),0x01 # retest problem state after cleanup
127 0: lg %r14,__LC_ASYNC_STACK # are we already on the async. stack ?
129 srag %r14,%r14,STACK_SHIFT
131 1: lg %r15,__LC_ASYNC_STACK # load async stack
132 #ifdef CONFIG_CHECK_STACK
134 2: tml %r15,STACK_SIZE - CONFIG_STACK_GUARD
141 .macro CREATE_STACK_FRAME psworg,savearea
142 aghi %r15,-SP_SIZE # make room for registers & psw
143 mvc SP_PSW(16,%r15),0(%r12) # move user PSW to stack
145 stg %r2,SP_ORIG_R2(%r15) # store original content of gpr 2
146 icm %r12,12,__LC_SVC_ILC
147 stmg %r0,%r11,SP_R0(%r15) # store gprs %r0-%r11 to kernel stack
149 mvc SP_R12(32,%r15),\savearea # move %r12-%r15 to stack
151 stg %r12,__SF_BACKCHAIN(%r15)
154 .macro RESTORE_ALL psworg,sync
155 mvc \psworg(16),SP_PSW(%r15) # move user PSW to lowcore
157 ni \psworg+1,0xfd # clear wait state bit
159 lmg %r0,%r15,SP_R0(%r15) # load gprs 0-15 of user
160 STORE_TIMER __LC_EXIT_TIMER
161 lpswe \psworg # back to caller
165 * Scheduler resume function, called by switch_to
166 * gpr2 = (task_struct *) prev
167 * gpr3 = (task_struct *) next
173 tm __THREAD_per+4(%r3),0xe8 # is the new process using per ?
174 jz __switch_to_noper # if not we're fine
175 stctg %c9,%c11,__SF_EMPTY(%r15)# We are using per stuff
176 clc __THREAD_per(24,%r3),__SF_EMPTY(%r15)
177 je __switch_to_noper # we got away without bashing TLB's
178 lctlg %c9,%c11,__THREAD_per(%r3) # Nope we didn't
180 lg %r4,__THREAD_info(%r2) # get thread_info of prev
181 tm __TI_flags+7(%r4),_TIF_MCCK_PENDING # machine check pending?
182 jz __switch_to_no_mcck
183 ni __TI_flags+7(%r4),255-_TIF_MCCK_PENDING # clear flag in prev
184 lg %r4,__THREAD_info(%r3) # get thread_info of next
185 oi __TI_flags+7(%r4),_TIF_MCCK_PENDING # set it in next
187 stmg %r6,%r15,__SF_GPRS(%r15)# store __switch_to registers of prev task
188 stg %r15,__THREAD_ksp(%r2) # store kernel stack to prev->tss.ksp
189 lg %r15,__THREAD_ksp(%r3) # load kernel stack from next->tss.ksp
190 lmg %r6,%r15,__SF_GPRS(%r15)# load __switch_to registers of next task
191 stg %r3,__LC_CURRENT # __LC_CURRENT = current task struct
192 lctl %c4,%c4,__TASK_pid(%r3) # load pid to control reg. 4
193 lg %r3,__THREAD_info(%r3) # load thread_info from task struct
194 stg %r3,__LC_THREAD_INFO
196 stg %r3,__LC_KERNEL_STACK # __LC_KERNEL_STACK = new kernel stack
201 * SVC interrupt handler routine. System calls are synchronous events and
202 * are executed with interrupts enabled.
207 STORE_TIMER __LC_SYNC_ENTER_TIMER
209 SAVE_ALL_BASE __LC_SAVE_AREA
210 SAVE_ALL_SYNC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
211 CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
212 llgh %r7,__LC_SVC_INT_CODE # get svc number from lowcore
213 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
215 tm SP_PSW+1(%r15),0x01 # interrupting from user ?
217 UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
219 UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
221 mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
224 lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
225 slag %r7,%r7,2 # *4 and test for svc 0
227 # svc 0: system call number in %r1
228 cl %r1,BASED(.Lnr_syscalls)
230 lgfr %r7,%r1 # clear high word in r1
231 slag %r7,%r7,2 # svc 0: system call number in %r1
233 mvc SP_ARGS(8,%r15),SP_R7(%r15)
235 larl %r10,sys_call_table
237 tm __TI_flags+5(%r9),(_TIF_31BIT>>16) # running in 31 bit mode ?
239 larl %r10,sys_call_table_emu # use 31 bit emulation system calls
242 tm __TI_flags+7(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
243 lgf %r8,0(%r7,%r10) # load address of system call routine
245 basr %r14,%r8 # call sys_xxxx
246 stg %r2,SP_R2(%r15) # store return value (change R2 on stack)
247 # ATTENTION: check sys_execve_glue before
248 # changing anything here !!
251 tm SP_PSW+1(%r15),0x01 # returning to user ?
253 tm __TI_flags+7(%r9),_TIF_WORK_SVC
254 jnz sysc_work # there is work to do (signals etc.)
256 RESTORE_ALL __LC_RETURN_PSW,1
259 # recheck if there is more work to do
262 tm __TI_flags+7(%r9),_TIF_WORK_SVC
263 jz sysc_leave # there is no work to do
265 # One of the work bits is on. Find out which one.
268 tm __TI_flags+7(%r9),_TIF_MCCK_PENDING
270 tm __TI_flags+7(%r9),_TIF_NEED_RESCHED
272 tm __TI_flags+7(%r9),(_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK)
274 tm __TI_flags+7(%r9),_TIF_RESTART_SVC
276 tm __TI_flags+7(%r9),_TIF_SINGLE_STEP
281 # _TIF_NEED_RESCHED is set, call schedule
284 larl %r14,sysc_work_loop
285 jg schedule # return point is sysc_return
288 # _TIF_MCCK_PENDING is set, call handler
291 larl %r14,sysc_work_loop
292 jg s390_handle_mcck # TIF bit will be cleared by handler
295 # _TIF_SIGPENDING or _TIF_RESTORE_SIGMASK is set, call do_signal
298 ni __TI_flags+7(%r9),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
299 la %r2,SP_PTREGS(%r15) # load pt_regs
300 brasl %r14,do_signal # call do_signal
301 tm __TI_flags+7(%r9),_TIF_RESTART_SVC
303 tm __TI_flags+7(%r9),_TIF_SINGLE_STEP
308 # _TIF_RESTART_SVC is set, set up registers and restart svc
311 ni __TI_flags+7(%r9),255-_TIF_RESTART_SVC # clear TIF_RESTART_SVC
312 lg %r7,SP_R2(%r15) # load new svc number
314 mvc SP_R2(8,%r15),SP_ORIG_R2(%r15) # restore first argument
315 lmg %r2,%r6,SP_R2(%r15) # load svc arguments
316 j sysc_do_restart # restart svc
319 # _TIF_SINGLE_STEP is set, call do_single_step
322 ni __TI_flags+7(%r9),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
323 lhi %r0,__LC_PGM_OLD_PSW
324 sth %r0,SP_TRAP(%r15) # set trap indication to pgm check
325 la %r2,SP_PTREGS(%r15) # address of register-save area
326 larl %r14,sysc_return # load adr. of system return
327 jg do_single_step # branch to do_sigtrap
331 # call syscall_trace before and after system call
332 # special linkage: %r12 contains the return address for trace_svc
335 la %r2,SP_PTREGS(%r15) # load pt_regs
339 brasl %r14,syscall_trace
343 lg %r7,SP_R2(%r15) # strace might have changed the
344 sll %r7,2 # system call
347 lmg %r3,%r6,SP_R3(%r15)
348 lg %r2,SP_ORIG_R2(%r15)
349 basr %r14,%r8 # call sys_xxx
350 stg %r2,SP_R2(%r15) # store return value
352 tm __TI_flags+7(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
354 la %r2,SP_PTREGS(%r15) # load pt_regs
356 larl %r14,sysc_return # return point is sysc_return
360 # a new process exits the kernel with ret_from_fork
364 lg %r13,__LC_SVC_NEW_PSW+8
365 lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
366 tm SP_PSW+1(%r15),0x01 # forking a kernel thread ?
368 stg %r15,SP_R15(%r15) # store stack pointer for new kthread
369 0: brasl %r14,schedule_tail
371 stosm 24(%r15),0x03 # reenable interrupts
375 # clone, fork, vfork, exec and sigreturn need glue,
376 # because they all expect pt_regs as parameter,
377 # but are called with different parameter.
378 # return-address is set up above
381 la %r2,SP_PTREGS(%r15) # load pt_regs
382 jg sys_clone # branch to sys_clone
386 la %r2,SP_PTREGS(%r15) # load pt_regs
387 jg sys32_clone # branch to sys32_clone
391 la %r2,SP_PTREGS(%r15) # load pt_regs
392 jg sys_fork # branch to sys_fork
395 la %r2,SP_PTREGS(%r15) # load pt_regs
396 jg sys_vfork # branch to sys_vfork
399 la %r2,SP_PTREGS(%r15) # load pt_regs
400 lgr %r12,%r14 # save return address
401 brasl %r14,sys_execve # call sys_execve
402 ltgr %r2,%r2 # check if execve failed
403 bnz 0(%r12) # it did fail -> store result in gpr2
404 b 6(%r12) # SKIP STG 2,SP_R2(15) in
405 # system_call/sysc_tracesys
408 la %r2,SP_PTREGS(%r15) # load pt_regs
409 lgr %r12,%r14 # save return address
410 brasl %r14,sys32_execve # call sys32_execve
411 ltgr %r2,%r2 # check if execve failed
412 bnz 0(%r12) # it did fail -> store result in gpr2
413 b 6(%r12) # SKIP STG 2,SP_R2(15) in
414 # system_call/sysc_tracesys
418 la %r2,SP_PTREGS(%r15) # load pt_regs as parameter
419 jg sys_sigreturn # branch to sys_sigreturn
422 sys32_sigreturn_glue:
423 la %r2,SP_PTREGS(%r15) # load pt_regs as parameter
424 jg sys32_sigreturn # branch to sys32_sigreturn
427 sys_rt_sigreturn_glue:
428 la %r2,SP_PTREGS(%r15) # load pt_regs as parameter
429 jg sys_rt_sigreturn # branch to sys_sigreturn
432 sys32_rt_sigreturn_glue:
433 la %r2,SP_PTREGS(%r15) # load pt_regs as parameter
434 jg sys32_rt_sigreturn # branch to sys32_sigreturn
437 sys_sigaltstack_glue:
438 la %r4,SP_PTREGS(%r15) # load pt_regs as parameter
439 jg sys_sigaltstack # branch to sys_sigreturn
442 sys32_sigaltstack_glue:
443 la %r4,SP_PTREGS(%r15) # load pt_regs as parameter
444 jg sys32_sigaltstack_wrapper # branch to sys_sigreturn
448 * Program check handler routine
451 .globl pgm_check_handler
454 * First we need to check for a special case:
455 * Single stepping an instruction that disables the PER event mask will
456 * cause a PER event AFTER the mask has been set. Example: SVC or LPSW.
457 * For a single stepped SVC the program check handler gets control after
458 * the SVC new PSW has been loaded. But we want to execute the SVC first and
459 * then handle the PER event. Therefore we update the SVC old PSW to point
460 * to the pgm_check_handler and branch to the SVC handler after we checked
461 * if we have to load the kernel stack register.
462 * For every other possible cause for PER event without the PER mask set
463 * we just ignore the PER event (FIXME: is there anything we have to do
466 STORE_TIMER __LC_SYNC_ENTER_TIMER
467 SAVE_ALL_BASE __LC_SAVE_AREA
468 tm __LC_PGM_INT_CODE+1,0x80 # check whether we got a per exception
469 jnz pgm_per # got per exception -> special case
470 SAVE_ALL_SYNC __LC_PGM_OLD_PSW,__LC_SAVE_AREA
471 CREATE_STACK_FRAME __LC_PGM_OLD_PSW,__LC_SAVE_AREA
472 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
473 tm SP_PSW+1(%r15),0x01 # interrupting from user ?
475 UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
476 UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
477 mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
480 lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
481 lgf %r3,__LC_PGM_ILC # load program interruption code
486 larl %r1,pgm_check_table
487 lg %r1,0(%r8,%r1) # load address of handler routine
488 la %r2,SP_PTREGS(%r15) # address of register-save area
489 larl %r14,sysc_return
490 br %r1 # branch to interrupt-handler
493 # handle per exception
496 tm __LC_PGM_OLD_PSW,0x40 # test if per event recording is on
497 jnz pgm_per_std # ok, normal per event from user space
498 # ok its one of the special cases, now we need to find out which one
499 clc __LC_PGM_OLD_PSW(16),__LC_SVC_NEW_PSW
501 # no interesting special case, ignore PER event
502 lmg %r12,%r15,__LC_SAVE_AREA
503 lpswe __LC_PGM_OLD_PSW
506 # Normal per exception
509 SAVE_ALL_SYNC __LC_PGM_OLD_PSW,__LC_SAVE_AREA
510 CREATE_STACK_FRAME __LC_PGM_OLD_PSW,__LC_SAVE_AREA
511 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
512 tm SP_PSW+1(%r15),0x01 # interrupting from user ?
514 UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
515 UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
516 mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
519 lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
520 lg %r1,__TI_task(%r9)
521 mvc __THREAD_per+__PER_atmid(2,%r1),__LC_PER_ATMID
522 mvc __THREAD_per+__PER_address(8,%r1),__LC_PER_ADDRESS
523 mvc __THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID
524 oi __TI_flags+7(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
525 lgf %r3,__LC_PGM_ILC # load program interruption code
527 ngr %r8,%r3 # clear per-event-bit and ilc
532 # it was a single stepped SVC that is causing all the trouble
535 SAVE_ALL_SYNC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
536 CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
537 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
538 tm SP_PSW+1(%r15),0x01 # interrupting from user ?
540 UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
541 UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
542 mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
545 llgh %r7,__LC_SVC_INT_CODE # get svc number from lowcore
546 lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
547 lg %r1,__TI_task(%r9)
548 mvc __THREAD_per+__PER_atmid(2,%r1),__LC_PER_ATMID
549 mvc __THREAD_per+__PER_address(8,%r1),__LC_PER_ADDRESS
550 mvc __THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID
551 oi __TI_flags+7(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
553 stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
557 * IO interrupt handler routine
559 .globl io_int_handler
561 STORE_TIMER __LC_ASYNC_ENTER_TIMER
563 SAVE_ALL_BASE __LC_SAVE_AREA+32
564 SAVE_ALL_ASYNC __LC_IO_OLD_PSW,__LC_SAVE_AREA+32
565 CREATE_STACK_FRAME __LC_IO_OLD_PSW,__LC_SAVE_AREA+32
566 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
567 tm SP_PSW+1(%r15),0x01 # interrupting from user ?
569 UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
570 UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
571 mvc __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
574 lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
576 la %r2,SP_PTREGS(%r15) # address of register-save area
577 brasl %r14,do_IRQ # call standard irq handler
581 tm SP_PSW+1(%r15),0x01 # returning to user ?
582 #ifdef CONFIG_PREEMPT
583 jno io_preempt # no -> check for preemptive scheduling
585 jno io_leave # no-> skip resched & signal
587 tm __TI_flags+7(%r9),_TIF_WORK_INT
588 jnz io_work # there is work to do (signals etc.)
590 RESTORE_ALL __LC_RETURN_PSW,0
593 #ifdef CONFIG_PREEMPT
595 icm %r0,15,__TI_precount(%r9)
597 # switch to kernel stack
600 mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
601 xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1) # clear back chain
604 tm __TI_flags+7(%r9),_TIF_NEED_RESCHED
607 mvc __TI_precount(4,%r9),0(%r1)
608 stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
609 brasl %r14,schedule # call schedule
610 stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
611 xc __TI_precount(4,%r9),__TI_precount(%r9)
616 # switch to kernel stack, then check TIF bits
619 lg %r1,__LC_KERNEL_STACK
621 mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
622 xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1) # clear back chain
625 # One of the work bits is on. Find out which one.
626 # Checked are: _TIF_SIGPENDING, _TIF_RESTORE_SIGPENDING, _TIF_NEED_RESCHED
627 # and _TIF_MCCK_PENDING
630 tm __TI_flags+7(%r9),_TIF_MCCK_PENDING
632 tm __TI_flags+7(%r9),_TIF_NEED_RESCHED
634 tm __TI_flags+7(%r9),(_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK)
639 # _TIF_MCCK_PENDING is set, call handler
642 larl %r14,io_work_loop
643 jg s390_handle_mcck # TIF bit will be cleared by handler
646 # _TIF_NEED_RESCHED is set, call schedule
649 stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
650 brasl %r14,schedule # call scheduler
651 stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
652 tm __TI_flags+7(%r9),_TIF_WORK_INT
653 jz io_leave # there is no work to do
657 # _TIF_SIGPENDING or _TIF_RESTORE_SIGMASK is set, call do_signal
660 stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
661 la %r2,SP_PTREGS(%r15) # load pt_regs
662 brasl %r14,do_signal # call do_signal
663 stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
667 * External interrupt handler routine
669 .globl ext_int_handler
671 STORE_TIMER __LC_ASYNC_ENTER_TIMER
673 SAVE_ALL_BASE __LC_SAVE_AREA+32
674 SAVE_ALL_ASYNC __LC_EXT_OLD_PSW,__LC_SAVE_AREA+32
675 CREATE_STACK_FRAME __LC_EXT_OLD_PSW,__LC_SAVE_AREA+32
676 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
677 tm SP_PSW+1(%r15),0x01 # interrupting from user ?
679 UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
680 UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
681 mvc __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
684 lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
686 la %r2,SP_PTREGS(%r15) # address of register-save area
687 llgh %r3,__LC_EXT_INT_CODE # get interruption code
695 * Machine check handler routines
697 .globl mcck_int_handler
699 la %r1,4095 # revalidate r1
700 spt __LC_CPU_TIMER_SAVE_AREA-4095(%r1) # revalidate cpu timer
701 lmg %r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r1)# revalidate gprs
702 SAVE_ALL_BASE __LC_SAVE_AREA+64
703 la %r12,__LC_MCK_OLD_PSW
704 tm __LC_MCCK_CODE,0x80 # system damage?
705 jo mcck_int_main # yes -> rest of mcck code invalid
706 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
708 mvc __LC_SAVE_AREA+104(8),__LC_ASYNC_ENTER_TIMER
709 mvc __LC_ASYNC_ENTER_TIMER(8),__LC_CPU_TIMER_SAVE_AREA-4095(%r14)
710 tm __LC_MCCK_CODE+5,0x02 # stored cpu timer value valid?
712 la %r14,__LC_SYNC_ENTER_TIMER
713 clc 0(8,%r14),__LC_ASYNC_ENTER_TIMER
715 la %r14,__LC_ASYNC_ENTER_TIMER
716 0: clc 0(8,%r14),__LC_EXIT_TIMER
718 la %r14,__LC_EXIT_TIMER
719 0: clc 0(8,%r14),__LC_LAST_UPDATE_TIMER
721 la %r14,__LC_LAST_UPDATE_TIMER
723 mvc __LC_ASYNC_ENTER_TIMER(8),0(%r14)
726 tm __LC_MCCK_CODE+2,0x09 # mwp + ia of old psw valid?
727 jno mcck_int_main # no -> skip cleanup critical
728 tm __LC_MCK_OLD_PSW+1,0x01 # test problem state bit
729 jnz mcck_int_main # from user -> load kernel stack
730 clc __LC_MCK_OLD_PSW+8(8),BASED(.Lcritical_end)
732 clc __LC_MCK_OLD_PSW+8(8),BASED(.Lcritical_start)
734 brasl %r14,cleanup_critical
736 lg %r14,__LC_PANIC_STACK # are we already on the panic stack?
738 srag %r14,%r14,PAGE_SHIFT
740 lg %r15,__LC_PANIC_STACK # load panic stack
741 0: CREATE_STACK_FRAME __LC_MCK_OLD_PSW,__LC_SAVE_AREA+64
742 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
743 tm __LC_MCCK_CODE+2,0x08 # mwp of old psw valid?
744 jno mcck_no_vtime # no -> no timer update
745 tm SP_PSW+1(%r15),0x01 # interrupting from user ?
747 UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
748 UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
749 mvc __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
752 lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
753 la %r2,SP_PTREGS(%r15) # load pt_regs
754 brasl %r14,s390_do_machine_check
755 tm SP_PSW+1(%r15),0x01 # returning to user ?
757 lg %r1,__LC_KERNEL_STACK # switch to kernel stack
759 mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
760 xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1) # clear back chain
762 stosm __SF_EMPTY(%r15),0x04 # turn dat on
763 tm __TI_flags+7(%r9),_TIF_MCCK_PENDING
766 brasl %r14,s390_handle_mcck
769 mvc __LC_RETURN_MCCK_PSW(16),SP_PSW(%r15) # move return PSW
770 ni __LC_RETURN_MCCK_PSW+1,0xfd # clear wait state bit
771 lmg %r0,%r15,SP_R0(%r15) # load gprs 0-15
772 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
773 mvc __LC_ASYNC_ENTER_TIMER(8),__LC_SAVE_AREA+104
774 tm __LC_RETURN_MCCK_PSW+1,0x01 # returning to user ?
779 lpswe __LC_RETURN_MCCK_PSW # back to caller
783 * Restart interruption handler, kick starter for additional CPUs
785 .globl restart_int_handler
787 lg %r15,__LC_SAVE_AREA+120 # load ksp
788 lghi %r10,__LC_CREGS_SAVE_AREA
789 lctlg %c0,%c15,0(%r10) # get new ctl regs
790 lghi %r10,__LC_AREGS_SAVE_AREA
792 lmg %r6,%r15,__SF_GPRS(%r15) # load registers from clone
793 stosm __SF_EMPTY(%r15),0x04 # now we can turn dat on
797 * If we do not run with SMP enabled, let the new CPU crash ...
799 .globl restart_int_handler
803 lpswe restart_crash-restart_base(%r1)
806 .long 0x000a0000,0x00000000,0x00000000,0x00000000
810 #ifdef CONFIG_CHECK_STACK
812 * The synchronous or the asynchronous stack overflowed. We are dead.
813 * No need to properly save the registers, we are going to panic anyway.
814 * Setup a pt_regs so that show_trace can provide a good call trace.
817 lg %r15,__LC_PANIC_STACK # change to panic stack
819 mvc SP_PSW(16,%r15),0(%r12) # move user PSW to stack
820 stmg %r0,%r11,SP_R0(%r15) # store gprs %r0-%r11 to kernel stack
821 la %r1,__LC_SAVE_AREA
822 chi %r12,__LC_SVC_OLD_PSW
824 chi %r12,__LC_PGM_OLD_PSW
826 la %r1,__LC_SAVE_AREA+16
827 0: mvc SP_R12(32,%r15),0(%r1) # move %r12-%r15 to stack
828 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) # clear back chain
829 la %r2,SP_PTREGS(%r15) # load pt_regs
830 jg kernel_stack_overflow
833 cleanup_table_system_call:
834 .quad system_call, sysc_do_svc
835 cleanup_table_sysc_return:
836 .quad sysc_return, sysc_leave
837 cleanup_table_sysc_leave:
838 .quad sysc_leave, sysc_work_loop
839 cleanup_table_sysc_work_loop:
840 .quad sysc_work_loop, sysc_reschedule
841 cleanup_table_io_return:
842 .quad io_return, io_leave
843 cleanup_table_io_leave:
844 .quad io_leave, io_done
845 cleanup_table_io_work_loop:
846 .quad io_work_loop, io_mcck_pending
849 clc 8(8,%r12),BASED(cleanup_table_system_call)
851 clc 8(8,%r12),BASED(cleanup_table_system_call+8)
852 jl cleanup_system_call
854 clc 8(8,%r12),BASED(cleanup_table_sysc_return)
856 clc 8(8,%r12),BASED(cleanup_table_sysc_return+8)
857 jl cleanup_sysc_return
859 clc 8(8,%r12),BASED(cleanup_table_sysc_leave)
861 clc 8(8,%r12),BASED(cleanup_table_sysc_leave+8)
862 jl cleanup_sysc_leave
864 clc 8(8,%r12),BASED(cleanup_table_sysc_work_loop)
866 clc 8(8,%r12),BASED(cleanup_table_sysc_work_loop+8)
867 jl cleanup_sysc_return
869 clc 8(8,%r12),BASED(cleanup_table_io_return)
871 clc 8(8,%r12),BASED(cleanup_table_io_return+8)
874 clc 8(8,%r12),BASED(cleanup_table_io_leave)
876 clc 8(8,%r12),BASED(cleanup_table_io_leave+8)
879 clc 8(8,%r12),BASED(cleanup_table_io_work_loop)
881 clc 8(8,%r12),BASED(cleanup_table_io_work_loop+8)
887 mvc __LC_RETURN_PSW(16),0(%r12)
888 cghi %r12,__LC_MCK_OLD_PSW
890 la %r12,__LC_SAVE_AREA+32
892 0: la %r12,__LC_SAVE_AREA+64
894 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
895 clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn+8)
897 mvc __LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER
898 0: clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn+16)
901 clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn)
903 mvc __LC_SAVE_AREA(32),0(%r12)
905 stg %r12,__LC_SAVE_AREA+96 # argh
906 SAVE_ALL_SYNC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
907 CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
908 lg %r12,__LC_SAVE_AREA+96 # argh
910 llgh %r7,__LC_SVC_INT_CODE
911 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
913 clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn+24)
915 tm SP_PSW+1(%r15),0x01 # interrupting from user ?
917 UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
919 clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn+32)
921 UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
923 mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
926 mvc __LC_RETURN_PSW+8(8),BASED(cleanup_table_system_call+8)
927 la %r12,__LC_RETURN_PSW
929 cleanup_system_call_insn:
931 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
939 mvc __LC_RETURN_PSW(8),0(%r12)
940 mvc __LC_RETURN_PSW+8(8),BASED(cleanup_table_sysc_return)
941 la %r12,__LC_RETURN_PSW
945 clc 8(8,%r12),BASED(cleanup_sysc_leave_insn)
947 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
948 mvc __LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER
949 clc 8(8,%r12),BASED(cleanup_sysc_leave_insn+8)
952 mvc __LC_RETURN_PSW(16),SP_PSW(%r15)
953 cghi %r12,__LC_MCK_OLD_PSW
955 mvc __LC_SAVE_AREA+64(32),SP_R12(%r15)
957 0: mvc __LC_SAVE_AREA+32(32),SP_R12(%r15)
958 1: lmg %r0,%r11,SP_R0(%r15)
960 2: la %r12,__LC_RETURN_PSW
962 cleanup_sysc_leave_insn:
963 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
964 .quad sysc_leave + 16
966 .quad sysc_leave + 12
969 mvc __LC_RETURN_PSW(8),0(%r12)
970 mvc __LC_RETURN_PSW+8(8),BASED(cleanup_table_io_work_loop)
971 la %r12,__LC_RETURN_PSW
975 clc 8(8,%r12),BASED(cleanup_io_leave_insn)
977 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
978 mvc __LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER
979 clc 8(8,%r12),BASED(cleanup_io_leave_insn+8)
982 mvc __LC_RETURN_PSW(16),SP_PSW(%r15)
983 cghi %r12,__LC_MCK_OLD_PSW
985 mvc __LC_SAVE_AREA+64(32),SP_R12(%r15)
987 0: mvc __LC_SAVE_AREA+32(32),SP_R12(%r15)
988 1: lmg %r0,%r11,SP_R0(%r15)
990 2: la %r12,__LC_RETURN_PSW
992 cleanup_io_leave_insn:
993 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
1003 .Lc_pactive: .long PREEMPT_ACTIVE
1004 .Lnr_syscalls: .long NR_syscalls
1005 .L0x0130: .short 0x130
1006 .L0x0140: .short 0x140
1007 .L0x0150: .short 0x150
1008 .L0x0160: .short 0x160
1009 .L0x0170: .short 0x170
1011 .quad __critical_start
1013 .quad __critical_end
1015 .section .rodata, "a"
1016 #define SYSCALL(esa,esame,emu) .long esame
1018 #include "syscalls.S"
1021 #ifdef CONFIG_COMPAT
1023 #define SYSCALL(esa,esame,emu) .long emu
1025 #include "syscalls.S"