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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 */
10
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>
20#include <asm/page.h>
21#include <asm/sigp.h>
22#include <asm/irq.h>
23#include <asm/vx-insn.h>
24#include <asm/setup.h>
25#include <asm/nmi.h>
26#include <asm/export.h>
27
28__PT_R0 = __PT_GPRS
29__PT_R1 = __PT_GPRS + 8
30__PT_R2 = __PT_GPRS + 16
31__PT_R3 = __PT_GPRS + 24
32__PT_R4 = __PT_GPRS + 32
33__PT_R5 = __PT_GPRS + 40
34__PT_R6 = __PT_GPRS + 48
35__PT_R7 = __PT_GPRS + 56
36__PT_R8 = __PT_GPRS + 64
37__PT_R9 = __PT_GPRS + 72
38__PT_R10 = __PT_GPRS + 80
39__PT_R11 = __PT_GPRS + 88
40__PT_R12 = __PT_GPRS + 96
41__PT_R13 = __PT_GPRS + 104
42__PT_R14 = __PT_GPRS + 112
43__PT_R15 = __PT_GPRS + 120
44
45STACK_SHIFT = PAGE_SHIFT + THREAD_SIZE_ORDER
46STACK_SIZE = 1 << STACK_SHIFT
47STACK_INIT = STACK_SIZE - STACK_FRAME_OVERHEAD - __PT_SIZE
48
49_TIF_WORK = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
50 _TIF_UPROBE)
51_TIF_TRACE = (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | \
52 _TIF_SYSCALL_TRACEPOINT)
53_CIF_WORK = (_CIF_MCCK_PENDING | _CIF_ASCE | _CIF_FPU)
54_PIF_WORK = (_PIF_PER_TRAP)
55
56#define BASED(name) name-cleanup_critical(%r13)
57
58 .macro TRACE_IRQS_ON
59#ifdef CONFIG_TRACE_IRQFLAGS
60 basr %r2,%r0
61 brasl %r14,trace_hardirqs_on_caller
62#endif
63 .endm
64
65 .macro TRACE_IRQS_OFF
66#ifdef CONFIG_TRACE_IRQFLAGS
67 basr %r2,%r0
68 brasl %r14,trace_hardirqs_off_caller
69#endif
70 .endm
71
72 .macro LOCKDEP_SYS_EXIT
73#ifdef CONFIG_LOCKDEP
74 tm __PT_PSW+1(%r11),0x01 # returning to user ?
75 jz .+10
76 brasl %r14,lockdep_sys_exit
77#endif
78 .endm
79
80 .macro CHECK_STACK stacksize,savearea
81#ifdef CONFIG_CHECK_STACK
82 tml %r15,\stacksize - CONFIG_STACK_GUARD
83 lghi %r14,\savearea
84 jz stack_overflow
85#endif
86 .endm
87
88 .macro SWITCH_ASYNC savearea,timer
89 tmhh %r8,0x0001 # interrupting from user ?
90 jnz 1f
91 lgr %r14,%r9
92 slg %r14,BASED(.Lcritical_start)
93 clg %r14,BASED(.Lcritical_length)
94 jhe 0f
95 lghi %r11,\savearea # inside critical section, do cleanup
96 brasl %r14,cleanup_critical
97 tmhh %r8,0x0001 # retest problem state after cleanup
98 jnz 1f
990: lg %r14,__LC_ASYNC_STACK # are we already on the async stack?
100 slgr %r14,%r15
101 srag %r14,%r14,STACK_SHIFT
102 jnz 2f
103 CHECK_STACK 1<<STACK_SHIFT,\savearea
104 aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
105 j 3f
1061: LAST_BREAK %r14
107 UPDATE_VTIME %r14,%r15,\timer
1082: lg %r15,__LC_ASYNC_STACK # load async stack
1093: la %r11,STACK_FRAME_OVERHEAD(%r15)
110 .endm
111
112 .macro UPDATE_VTIME w1,w2,enter_timer
113 lg \w1,__LC_EXIT_TIMER
114 lg \w2,__LC_LAST_UPDATE_TIMER
115 slg \w1,\enter_timer
116 slg \w2,__LC_EXIT_TIMER
117 alg \w1,__LC_USER_TIMER
118 alg \w2,__LC_SYSTEM_TIMER
119 stg \w1,__LC_USER_TIMER
120 stg \w2,__LC_SYSTEM_TIMER
121 mvc __LC_LAST_UPDATE_TIMER(8),\enter_timer
122 .endm
123
124 .macro LAST_BREAK scratch
125 srag \scratch,%r10,23
126#ifdef CONFIG_HAVE_MARCH_Z990_FEATURES
127 jz .+10
128 stg %r10,__TASK_thread+__THREAD_last_break(%r12)
129#else
130 jz .+14
131 lghi \scratch,__TASK_thread
132 stg %r10,__THREAD_last_break(\scratch,%r12)
133#endif
134 .endm
135
136 .macro REENABLE_IRQS
137 stg %r8,__LC_RETURN_PSW
138 ni __LC_RETURN_PSW,0xbf
139 ssm __LC_RETURN_PSW
140 .endm
141
142 .macro STCK savearea
143#ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
144 .insn s,0xb27c0000,\savearea # store clock fast
145#else
146 .insn s,0xb2050000,\savearea # store clock
147#endif
148 .endm
149
150 /*
151 * The TSTMSK macro generates a test-under-mask instruction by
152 * calculating the memory offset for the specified mask value.
153 * Mask value can be any constant. The macro shifts the mask
154 * value to calculate the memory offset for the test-under-mask
155 * instruction.
156 */
157 .macro TSTMSK addr, mask, size=8, bytepos=0
158 .if (\bytepos < \size) && (\mask >> 8)
159 .if (\mask & 0xff)
160 .error "Mask exceeds byte boundary"
161 .endif
162 TSTMSK \addr, "(\mask >> 8)", \size, "(\bytepos + 1)"
163 .exitm
164 .endif
165 .ifeq \mask
166 .error "Mask must not be zero"
167 .endif
168 off = \size - \bytepos - 1
169 tm off+\addr, \mask
170 .endm
171
172 .section .kprobes.text, "ax"
173.Ldummy:
174 /*
175 * This nop exists only in order to avoid that __switch_to starts at
176 * the beginning of the kprobes text section. In that case we would
177 * have several symbols at the same address. E.g. objdump would take
178 * an arbitrary symbol name when disassembling this code.
179 * With the added nop in between the __switch_to symbol is unique
180 * again.
181 */
182 nop 0
183
184/*
185 * Scheduler resume function, called by switch_to
186 * gpr2 = (task_struct *) prev
187 * gpr3 = (task_struct *) next
188 * Returns:
189 * gpr2 = prev
190 */
191ENTRY(__switch_to)
192 stmg %r6,%r15,__SF_GPRS(%r15) # store gprs of prev task
193 lgr %r1,%r2
194 aghi %r1,__TASK_thread # thread_struct of prev task
195 lg %r5,__TASK_stack(%r3) # start of kernel stack of next
196 stg %r15,__THREAD_ksp(%r1) # store kernel stack of prev
197 lgr %r1,%r3
198 aghi %r1,__TASK_thread # thread_struct of next task
199 lgr %r15,%r5
200 aghi %r15,STACK_INIT # end of kernel stack of next
201 stg %r3,__LC_CURRENT # store task struct of next
202 stg %r15,__LC_KERNEL_STACK # store end of kernel stack
203 lg %r15,__THREAD_ksp(%r1) # load kernel stack of next
204 /* c4 is used in guest detection: arch/s390/kernel/perf_cpum_sf.c */
205 lctl %c4,%c4,__TASK_pid(%r3) # load pid to control reg. 4
206 mvc __LC_CURRENT_PID(4,%r0),__TASK_pid(%r3) # store pid of next
207 lmg %r6,%r15,__SF_GPRS(%r15) # load gprs of next task
208 TSTMSK __LC_MACHINE_FLAGS,MACHINE_FLAG_LPP
209 bzr %r14
210 .insn s,0xb2800000,__LC_LPP # set program parameter
211 br %r14
212
213.L__critical_start:
214
215#if IS_ENABLED(CONFIG_KVM)
216/*
217 * sie64a calling convention:
218 * %r2 pointer to sie control block
219 * %r3 guest register save area
220 */
221ENTRY(sie64a)
222 stmg %r6,%r14,__SF_GPRS(%r15) # save kernel registers
223 stg %r2,__SF_EMPTY(%r15) # save control block pointer
224 stg %r3,__SF_EMPTY+8(%r15) # save guest register save area
225 xc __SF_EMPTY+16(8,%r15),__SF_EMPTY+16(%r15) # reason code = 0
226 TSTMSK __LC_CPU_FLAGS,_CIF_FPU # load guest fp/vx registers ?
227 jno .Lsie_load_guest_gprs
228 brasl %r14,load_fpu_regs # load guest fp/vx regs
229.Lsie_load_guest_gprs:
230 lmg %r0,%r13,0(%r3) # load guest gprs 0-13
231 lg %r14,__LC_GMAP # get gmap pointer
232 ltgr %r14,%r14
233 jz .Lsie_gmap
234 lctlg %c1,%c1,__GMAP_ASCE(%r14) # load primary asce
235.Lsie_gmap:
236 lg %r14,__SF_EMPTY(%r15) # get control block pointer
237 oi __SIE_PROG0C+3(%r14),1 # we are going into SIE now
238 tm __SIE_PROG20+3(%r14),3 # last exit...
239 jnz .Lsie_skip
240 TSTMSK __LC_CPU_FLAGS,_CIF_FPU
241 jo .Lsie_skip # exit if fp/vx regs changed
242 sie 0(%r14)
243.Lsie_skip:
244 ni __SIE_PROG0C+3(%r14),0xfe # no longer in SIE
245 lctlg %c1,%c1,__LC_USER_ASCE # load primary asce
246.Lsie_done:
247# some program checks are suppressing. C code (e.g. do_protection_exception)
248# will rewind the PSW by the ILC, which is 4 bytes in case of SIE. Other
249# instructions between sie64a and .Lsie_done should not cause program
250# interrupts. So lets use a nop (47 00 00 00) as a landing pad.
251# See also .Lcleanup_sie
252.Lrewind_pad:
253 nop 0
254 .globl sie_exit
255sie_exit:
256 lg %r14,__SF_EMPTY+8(%r15) # load guest register save area
257 stmg %r0,%r13,0(%r14) # save guest gprs 0-13
258 lmg %r6,%r14,__SF_GPRS(%r15) # restore kernel registers
259 lg %r2,__SF_EMPTY+16(%r15) # return exit reason code
260 br %r14
261.Lsie_fault:
262 lghi %r14,-EFAULT
263 stg %r14,__SF_EMPTY+16(%r15) # set exit reason code
264 j sie_exit
265
266 EX_TABLE(.Lrewind_pad,.Lsie_fault)
267 EX_TABLE(sie_exit,.Lsie_fault)
268EXPORT_SYMBOL(sie64a)
269EXPORT_SYMBOL(sie_exit)
270#endif
271
272/*
273 * SVC interrupt handler routine. System calls are synchronous events and
274 * are executed with interrupts enabled.
275 */
276
277ENTRY(system_call)
278 stpt __LC_SYNC_ENTER_TIMER
279.Lsysc_stmg:
280 stmg %r8,%r15,__LC_SAVE_AREA_SYNC
281 lg %r10,__LC_LAST_BREAK
282 lg %r12,__LC_CURRENT
283 lghi %r14,_PIF_SYSCALL
284.Lsysc_per:
285 lg %r15,__LC_KERNEL_STACK
286 la %r11,STACK_FRAME_OVERHEAD(%r15) # pointer to pt_regs
287 LAST_BREAK %r13
288.Lsysc_vtime:
289 UPDATE_VTIME %r10,%r13,__LC_SYNC_ENTER_TIMER
290 stmg %r0,%r7,__PT_R0(%r11)
291 mvc __PT_R8(64,%r11),__LC_SAVE_AREA_SYNC
292 mvc __PT_PSW(16,%r11),__LC_SVC_OLD_PSW
293 mvc __PT_INT_CODE(4,%r11),__LC_SVC_ILC
294 stg %r14,__PT_FLAGS(%r11)
295.Lsysc_do_svc:
296 # load address of system call table
297#ifdef CONFIG_HAVE_MARCH_Z990_FEATURES
298 lg %r10,__TASK_thread+__THREAD_sysc_table(%r12)
299#else
300 lghi %r13,__TASK_thread
301 lg %r10,__THREAD_sysc_table(%r13,%r12)
302#endif
303 llgh %r8,__PT_INT_CODE+2(%r11)
304 slag %r8,%r8,2 # shift and test for svc 0
305 jnz .Lsysc_nr_ok
306 # svc 0: system call number in %r1
307 llgfr %r1,%r1 # clear high word in r1
308 cghi %r1,NR_syscalls
309 jnl .Lsysc_nr_ok
310 sth %r1,__PT_INT_CODE+2(%r11)
311 slag %r8,%r1,2
312.Lsysc_nr_ok:
313 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
314 stg %r2,__PT_ORIG_GPR2(%r11)
315 stg %r7,STACK_FRAME_OVERHEAD(%r15)
316 lgf %r9,0(%r8,%r10) # get system call add.
317 TSTMSK __TI_flags(%r12),_TIF_TRACE
318 jnz .Lsysc_tracesys
319 basr %r14,%r9 # call sys_xxxx
320 stg %r2,__PT_R2(%r11) # store return value
321
322.Lsysc_return:
323 LOCKDEP_SYS_EXIT
324.Lsysc_tif:
325 TSTMSK __PT_FLAGS(%r11),_PIF_WORK
326 jnz .Lsysc_work
327 TSTMSK __TI_flags(%r12),_TIF_WORK
328 jnz .Lsysc_work # check for work
329 TSTMSK __LC_CPU_FLAGS,_CIF_WORK
330 jnz .Lsysc_work
331.Lsysc_restore:
332 lg %r14,__LC_VDSO_PER_CPU
333 lmg %r0,%r10,__PT_R0(%r11)
334 mvc __LC_RETURN_PSW(16),__PT_PSW(%r11)
335 stpt __LC_EXIT_TIMER
336 mvc __VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER
337 lmg %r11,%r15,__PT_R11(%r11)
338 lpswe __LC_RETURN_PSW
339.Lsysc_done:
340
341#
342# One of the work bits is on. Find out which one.
343#
344.Lsysc_work:
345 TSTMSK __LC_CPU_FLAGS,_CIF_MCCK_PENDING
346 jo .Lsysc_mcck_pending
347 TSTMSK __TI_flags(%r12),_TIF_NEED_RESCHED
348 jo .Lsysc_reschedule
349#ifdef CONFIG_UPROBES
350 TSTMSK __TI_flags(%r12),_TIF_UPROBE
351 jo .Lsysc_uprobe_notify
352#endif
353 TSTMSK __PT_FLAGS(%r11),_PIF_PER_TRAP
354 jo .Lsysc_singlestep
355 TSTMSK __TI_flags(%r12),_TIF_SIGPENDING
356 jo .Lsysc_sigpending
357 TSTMSK __TI_flags(%r12),_TIF_NOTIFY_RESUME
358 jo .Lsysc_notify_resume
359 TSTMSK __LC_CPU_FLAGS,_CIF_FPU
360 jo .Lsysc_vxrs
361 TSTMSK __LC_CPU_FLAGS,_CIF_ASCE
362 jo .Lsysc_uaccess
363 j .Lsysc_return # beware of critical section cleanup
364
365#
366# _TIF_NEED_RESCHED is set, call schedule
367#
368.Lsysc_reschedule:
369 larl %r14,.Lsysc_return
370 jg schedule
371
372#
373# _CIF_MCCK_PENDING is set, call handler
374#
375.Lsysc_mcck_pending:
376 larl %r14,.Lsysc_return
377 jg s390_handle_mcck # TIF bit will be cleared by handler
378
379#
380# _CIF_ASCE is set, load user space asce
381#
382.Lsysc_uaccess:
383 ni __LC_CPU_FLAGS+7,255-_CIF_ASCE
384 lctlg %c1,%c1,__LC_USER_ASCE # load primary asce
385 j .Lsysc_return
386
387#
388# CIF_FPU is set, restore floating-point controls and floating-point registers.
389#
390.Lsysc_vxrs:
391 larl %r14,.Lsysc_return
392 jg load_fpu_regs
393
394#
395# _TIF_SIGPENDING is set, call do_signal
396#
397.Lsysc_sigpending:
398 lgr %r2,%r11 # pass pointer to pt_regs
399 brasl %r14,do_signal
400 TSTMSK __PT_FLAGS(%r11),_PIF_SYSCALL
401 jno .Lsysc_return
402 lmg %r2,%r7,__PT_R2(%r11) # load svc arguments
403 lghi %r8,0 # svc 0 returns -ENOSYS
404 llgh %r1,__PT_INT_CODE+2(%r11) # load new svc number
405 cghi %r1,NR_syscalls
406 jnl .Lsysc_nr_ok # invalid svc number -> do svc 0
407 slag %r8,%r1,2
408 j .Lsysc_nr_ok # restart svc
409
410#
411# _TIF_NOTIFY_RESUME is set, call do_notify_resume
412#
413.Lsysc_notify_resume:
414 lgr %r2,%r11 # pass pointer to pt_regs
415 larl %r14,.Lsysc_return
416 jg do_notify_resume
417
418#
419# _TIF_UPROBE is set, call uprobe_notify_resume
420#
421#ifdef CONFIG_UPROBES
422.Lsysc_uprobe_notify:
423 lgr %r2,%r11 # pass pointer to pt_regs
424 larl %r14,.Lsysc_return
425 jg uprobe_notify_resume
426#endif
427
428#
429# _PIF_PER_TRAP is set, call do_per_trap
430#
431.Lsysc_singlestep:
432 ni __PT_FLAGS+7(%r11),255-_PIF_PER_TRAP
433 lgr %r2,%r11 # pass pointer to pt_regs
434 larl %r14,.Lsysc_return
435 jg do_per_trap
436
437#
438# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
439# and after the system call
440#
441.Lsysc_tracesys:
442 lgr %r2,%r11 # pass pointer to pt_regs
443 la %r3,0
444 llgh %r0,__PT_INT_CODE+2(%r11)
445 stg %r0,__PT_R2(%r11)
446 brasl %r14,do_syscall_trace_enter
447 lghi %r0,NR_syscalls
448 clgr %r0,%r2
449 jnh .Lsysc_tracenogo
450 sllg %r8,%r2,2
451 lgf %r9,0(%r8,%r10)
452.Lsysc_tracego:
453 lmg %r3,%r7,__PT_R3(%r11)
454 stg %r7,STACK_FRAME_OVERHEAD(%r15)
455 lg %r2,__PT_ORIG_GPR2(%r11)
456 basr %r14,%r9 # call sys_xxx
457 stg %r2,__PT_R2(%r11) # store return value
458.Lsysc_tracenogo:
459 TSTMSK __TI_flags(%r12),_TIF_TRACE
460 jz .Lsysc_return
461 lgr %r2,%r11 # pass pointer to pt_regs
462 larl %r14,.Lsysc_return
463 jg do_syscall_trace_exit
464
465#
466# a new process exits the kernel with ret_from_fork
467#
468ENTRY(ret_from_fork)
469 la %r11,STACK_FRAME_OVERHEAD(%r15)
470 lg %r12,__LC_CURRENT
471 brasl %r14,schedule_tail
472 TRACE_IRQS_ON
473 ssm __LC_SVC_NEW_PSW # reenable interrupts
474 tm __PT_PSW+1(%r11),0x01 # forking a kernel thread ?
475 jne .Lsysc_tracenogo
476 # it's a kernel thread
477 lmg %r9,%r10,__PT_R9(%r11) # load gprs
478ENTRY(kernel_thread_starter)
479 la %r2,0(%r10)
480 basr %r14,%r9
481 j .Lsysc_tracenogo
482
483/*
484 * Program check handler routine
485 */
486
487ENTRY(pgm_check_handler)
488 stpt __LC_SYNC_ENTER_TIMER
489 stmg %r8,%r15,__LC_SAVE_AREA_SYNC
490 lg %r10,__LC_LAST_BREAK
491 lg %r12,__LC_CURRENT
492 larl %r13,cleanup_critical
493 lmg %r8,%r9,__LC_PGM_OLD_PSW
494 tmhh %r8,0x0001 # test problem state bit
495 jnz 2f # -> fault in user space
496#if IS_ENABLED(CONFIG_KVM)
497 # cleanup critical section for sie64a
498 lgr %r14,%r9
499 slg %r14,BASED(.Lsie_critical_start)
500 clg %r14,BASED(.Lsie_critical_length)
501 jhe 0f
502 brasl %r14,.Lcleanup_sie
503#endif
5040: tmhh %r8,0x4000 # PER bit set in old PSW ?
505 jnz 1f # -> enabled, can't be a double fault
506 tm __LC_PGM_ILC+3,0x80 # check for per exception
507 jnz .Lpgm_svcper # -> single stepped svc
5081: CHECK_STACK STACK_SIZE,__LC_SAVE_AREA_SYNC
509 aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
510 j 3f
5112: LAST_BREAK %r14
512 UPDATE_VTIME %r14,%r15,__LC_SYNC_ENTER_TIMER
513 lg %r15,__LC_KERNEL_STACK
514 lgr %r14,%r12
515 aghi %r14,__TASK_thread # pointer to thread_struct
516 lghi %r13,__LC_PGM_TDB
517 tm __LC_PGM_ILC+2,0x02 # check for transaction abort
518 jz 3f
519 mvc __THREAD_trap_tdb(256,%r14),0(%r13)
5203: la %r11,STACK_FRAME_OVERHEAD(%r15)
521 stmg %r0,%r7,__PT_R0(%r11)
522 mvc __PT_R8(64,%r11),__LC_SAVE_AREA_SYNC
523 stmg %r8,%r9,__PT_PSW(%r11)
524 mvc __PT_INT_CODE(4,%r11),__LC_PGM_ILC
525 mvc __PT_INT_PARM_LONG(8,%r11),__LC_TRANS_EXC_CODE
526 xc __PT_FLAGS(8,%r11),__PT_FLAGS(%r11)
527 stg %r10,__PT_ARGS(%r11)
528 tm __LC_PGM_ILC+3,0x80 # check for per exception
529 jz 4f
530 tmhh %r8,0x0001 # kernel per event ?
531 jz .Lpgm_kprobe
532 oi __PT_FLAGS+7(%r11),_PIF_PER_TRAP
533 mvc __THREAD_per_address(8,%r14),__LC_PER_ADDRESS
534 mvc __THREAD_per_cause(2,%r14),__LC_PER_CODE
535 mvc __THREAD_per_paid(1,%r14),__LC_PER_ACCESS_ID
5364: REENABLE_IRQS
537 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
538 larl %r1,pgm_check_table
539 llgh %r10,__PT_INT_CODE+2(%r11)
540 nill %r10,0x007f
541 sll %r10,2
542 je .Lpgm_return
543 lgf %r1,0(%r10,%r1) # load address of handler routine
544 lgr %r2,%r11 # pass pointer to pt_regs
545 basr %r14,%r1 # branch to interrupt-handler
546.Lpgm_return:
547 LOCKDEP_SYS_EXIT
548 tm __PT_PSW+1(%r11),0x01 # returning to user ?
549 jno .Lsysc_restore
550 j .Lsysc_tif
551
552#
553# PER event in supervisor state, must be kprobes
554#
555.Lpgm_kprobe:
556 REENABLE_IRQS
557 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
558 lgr %r2,%r11 # pass pointer to pt_regs
559 brasl %r14,do_per_trap
560 j .Lpgm_return
561
562#
563# single stepped system call
564#
565.Lpgm_svcper:
566 mvc __LC_RETURN_PSW(8),__LC_SVC_NEW_PSW
567 larl %r14,.Lsysc_per
568 stg %r14,__LC_RETURN_PSW+8
569 lghi %r14,_PIF_SYSCALL | _PIF_PER_TRAP
570 lpswe __LC_RETURN_PSW # branch to .Lsysc_per and enable irqs
571
572/*
573 * IO interrupt handler routine
574 */
575ENTRY(io_int_handler)
576 STCK __LC_INT_CLOCK
577 stpt __LC_ASYNC_ENTER_TIMER
578 stmg %r8,%r15,__LC_SAVE_AREA_ASYNC
579 lg %r10,__LC_LAST_BREAK
580 lg %r12,__LC_CURRENT
581 larl %r13,cleanup_critical
582 lmg %r8,%r9,__LC_IO_OLD_PSW
583 SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_ENTER_TIMER
584 stmg %r0,%r7,__PT_R0(%r11)
585 mvc __PT_R8(64,%r11),__LC_SAVE_AREA_ASYNC
586 stmg %r8,%r9,__PT_PSW(%r11)
587 mvc __PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID
588 xc __PT_FLAGS(8,%r11),__PT_FLAGS(%r11)
589 TSTMSK __LC_CPU_FLAGS,_CIF_IGNORE_IRQ
590 jo .Lio_restore
591 TRACE_IRQS_OFF
592 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
593.Lio_loop:
594 lgr %r2,%r11 # pass pointer to pt_regs
595 lghi %r3,IO_INTERRUPT
596 tm __PT_INT_CODE+8(%r11),0x80 # adapter interrupt ?
597 jz .Lio_call
598 lghi %r3,THIN_INTERRUPT
599.Lio_call:
600 brasl %r14,do_IRQ
601 TSTMSK __LC_MACHINE_FLAGS,MACHINE_FLAG_LPAR
602 jz .Lio_return
603 tpi 0
604 jz .Lio_return
605 mvc __PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID
606 j .Lio_loop
607.Lio_return:
608 LOCKDEP_SYS_EXIT
609 TRACE_IRQS_ON
610.Lio_tif:
611 TSTMSK __TI_flags(%r12),_TIF_WORK
612 jnz .Lio_work # there is work to do (signals etc.)
613 TSTMSK __LC_CPU_FLAGS,_CIF_WORK
614 jnz .Lio_work
615.Lio_restore:
616 lg %r14,__LC_VDSO_PER_CPU
617 lmg %r0,%r10,__PT_R0(%r11)
618 mvc __LC_RETURN_PSW(16),__PT_PSW(%r11)
619 stpt __LC_EXIT_TIMER
620 mvc __VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER
621 lmg %r11,%r15,__PT_R11(%r11)
622 lpswe __LC_RETURN_PSW
623.Lio_done:
624
625#
626# There is work todo, find out in which context we have been interrupted:
627# 1) if we return to user space we can do all _TIF_WORK work
628# 2) if we return to kernel code and kvm is enabled check if we need to
629# modify the psw to leave SIE
630# 3) if we return to kernel code and preemptive scheduling is enabled check
631# the preemption counter and if it is zero call preempt_schedule_irq
632# Before any work can be done, a switch to the kernel stack is required.
633#
634.Lio_work:
635 tm __PT_PSW+1(%r11),0x01 # returning to user ?
636 jo .Lio_work_user # yes -> do resched & signal
637#ifdef CONFIG_PREEMPT
638 # check for preemptive scheduling
639 icm %r0,15,__LC_PREEMPT_COUNT
640 jnz .Lio_restore # preemption is disabled
641 TSTMSK __TI_flags(%r12),_TIF_NEED_RESCHED
642 jno .Lio_restore
643 # switch to kernel stack
644 lg %r1,__PT_R15(%r11)
645 aghi %r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
646 mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
647 xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1)
648 la %r11,STACK_FRAME_OVERHEAD(%r1)
649 lgr %r15,%r1
650 # TRACE_IRQS_ON already done at .Lio_return, call
651 # TRACE_IRQS_OFF to keep things symmetrical
652 TRACE_IRQS_OFF
653 brasl %r14,preempt_schedule_irq
654 j .Lio_return
655#else
656 j .Lio_restore
657#endif
658
659#
660# Need to do work before returning to userspace, switch to kernel stack
661#
662.Lio_work_user:
663 lg %r1,__LC_KERNEL_STACK
664 mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
665 xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1)
666 la %r11,STACK_FRAME_OVERHEAD(%r1)
667 lgr %r15,%r1
668
669#
670# One of the work bits is on. Find out which one.
671#
672.Lio_work_tif:
673 TSTMSK __LC_CPU_FLAGS,_CIF_MCCK_PENDING
674 jo .Lio_mcck_pending
675 TSTMSK __TI_flags(%r12),_TIF_NEED_RESCHED
676 jo .Lio_reschedule
677 TSTMSK __TI_flags(%r12),_TIF_SIGPENDING
678 jo .Lio_sigpending
679 TSTMSK __TI_flags(%r12),_TIF_NOTIFY_RESUME
680 jo .Lio_notify_resume
681 TSTMSK __LC_CPU_FLAGS,_CIF_FPU
682 jo .Lio_vxrs
683 TSTMSK __LC_CPU_FLAGS,_CIF_ASCE
684 jo .Lio_uaccess
685 j .Lio_return # beware of critical section cleanup
686
687#
688# _CIF_MCCK_PENDING is set, call handler
689#
690.Lio_mcck_pending:
691 # TRACE_IRQS_ON already done at .Lio_return
692 brasl %r14,s390_handle_mcck # TIF bit will be cleared by handler
693 TRACE_IRQS_OFF
694 j .Lio_return
695
696#
697# _CIF_ASCE is set, load user space asce
698#
699.Lio_uaccess:
700 ni __LC_CPU_FLAGS+7,255-_CIF_ASCE
701 lctlg %c1,%c1,__LC_USER_ASCE # load primary asce
702 j .Lio_return
703
704#
705# CIF_FPU is set, restore floating-point controls and floating-point registers.
706#
707.Lio_vxrs:
708 larl %r14,.Lio_return
709 jg load_fpu_regs
710
711#
712# _TIF_NEED_RESCHED is set, call schedule
713#
714.Lio_reschedule:
715 # TRACE_IRQS_ON already done at .Lio_return
716 ssm __LC_SVC_NEW_PSW # reenable interrupts
717 brasl %r14,schedule # call scheduler
718 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
719 TRACE_IRQS_OFF
720 j .Lio_return
721
722#
723# _TIF_SIGPENDING or is set, call do_signal
724#
725.Lio_sigpending:
726 # TRACE_IRQS_ON already done at .Lio_return
727 ssm __LC_SVC_NEW_PSW # reenable interrupts
728 lgr %r2,%r11 # pass pointer to pt_regs
729 brasl %r14,do_signal
730 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
731 TRACE_IRQS_OFF
732 j .Lio_return
733
734#
735# _TIF_NOTIFY_RESUME or is set, call do_notify_resume
736#
737.Lio_notify_resume:
738 # TRACE_IRQS_ON already done at .Lio_return
739 ssm __LC_SVC_NEW_PSW # reenable interrupts
740 lgr %r2,%r11 # pass pointer to pt_regs
741 brasl %r14,do_notify_resume
742 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
743 TRACE_IRQS_OFF
744 j .Lio_return
745
746/*
747 * External interrupt handler routine
748 */
749ENTRY(ext_int_handler)
750 STCK __LC_INT_CLOCK
751 stpt __LC_ASYNC_ENTER_TIMER
752 stmg %r8,%r15,__LC_SAVE_AREA_ASYNC
753 lg %r10,__LC_LAST_BREAK
754 lg %r12,__LC_CURRENT
755 larl %r13,cleanup_critical
756 lmg %r8,%r9,__LC_EXT_OLD_PSW
757 SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_ENTER_TIMER
758 stmg %r0,%r7,__PT_R0(%r11)
759 mvc __PT_R8(64,%r11),__LC_SAVE_AREA_ASYNC
760 stmg %r8,%r9,__PT_PSW(%r11)
761 lghi %r1,__LC_EXT_PARAMS2
762 mvc __PT_INT_CODE(4,%r11),__LC_EXT_CPU_ADDR
763 mvc __PT_INT_PARM(4,%r11),__LC_EXT_PARAMS
764 mvc __PT_INT_PARM_LONG(8,%r11),0(%r1)
765 xc __PT_FLAGS(8,%r11),__PT_FLAGS(%r11)
766 TSTMSK __LC_CPU_FLAGS,_CIF_IGNORE_IRQ
767 jo .Lio_restore
768 TRACE_IRQS_OFF
769 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
770 lgr %r2,%r11 # pass pointer to pt_regs
771 lghi %r3,EXT_INTERRUPT
772 brasl %r14,do_IRQ
773 j .Lio_return
774
775/*
776 * Load idle PSW. The second "half" of this function is in .Lcleanup_idle.
777 */
778ENTRY(psw_idle)
779 stg %r3,__SF_EMPTY(%r15)
780 larl %r1,.Lpsw_idle_lpsw+4
781 stg %r1,__SF_EMPTY+8(%r15)
782#ifdef CONFIG_SMP
783 larl %r1,smp_cpu_mtid
784 llgf %r1,0(%r1)
785 ltgr %r1,%r1
786 jz .Lpsw_idle_stcctm
787 .insn rsy,0xeb0000000017,%r1,5,__SF_EMPTY+16(%r15)
788.Lpsw_idle_stcctm:
789#endif
790 oi __LC_CPU_FLAGS+7,_CIF_ENABLED_WAIT
791 STCK __CLOCK_IDLE_ENTER(%r2)
792 stpt __TIMER_IDLE_ENTER(%r2)
793.Lpsw_idle_lpsw:
794 lpswe __SF_EMPTY(%r15)
795 br %r14
796.Lpsw_idle_end:
797
798/*
799 * Store floating-point controls and floating-point or vector register
800 * depending whether the vector facility is available. A critical section
801 * cleanup assures that the registers are stored even if interrupted for
802 * some other work. The CIF_FPU flag is set to trigger a lazy restore
803 * of the register contents at return from io or a system call.
804 */
805ENTRY(save_fpu_regs)
806 lg %r2,__LC_CURRENT
807 aghi %r2,__TASK_thread
808 TSTMSK __LC_CPU_FLAGS,_CIF_FPU
809 bor %r14
810 stfpc __THREAD_FPU_fpc(%r2)
811 lg %r3,__THREAD_FPU_regs(%r2)
812 TSTMSK __LC_MACHINE_FLAGS,MACHINE_FLAG_VX
813 jz .Lsave_fpu_regs_fp # no -> store FP regs
814 VSTM %v0,%v15,0,%r3 # vstm 0,15,0(3)
815 VSTM %v16,%v31,256,%r3 # vstm 16,31,256(3)
816 j .Lsave_fpu_regs_done # -> set CIF_FPU flag
817.Lsave_fpu_regs_fp:
818 std 0,0(%r3)
819 std 1,8(%r3)
820 std 2,16(%r3)
821 std 3,24(%r3)
822 std 4,32(%r3)
823 std 5,40(%r3)
824 std 6,48(%r3)
825 std 7,56(%r3)
826 std 8,64(%r3)
827 std 9,72(%r3)
828 std 10,80(%r3)
829 std 11,88(%r3)
830 std 12,96(%r3)
831 std 13,104(%r3)
832 std 14,112(%r3)
833 std 15,120(%r3)
834.Lsave_fpu_regs_done:
835 oi __LC_CPU_FLAGS+7,_CIF_FPU
836 br %r14
837.Lsave_fpu_regs_end:
838#if IS_ENABLED(CONFIG_KVM)
839EXPORT_SYMBOL(save_fpu_regs)
840#endif
841
842/*
843 * Load floating-point controls and floating-point or vector registers.
844 * A critical section cleanup assures that the register contents are
845 * loaded even if interrupted for some other work.
846 *
847 * There are special calling conventions to fit into sysc and io return work:
848 * %r15: <kernel stack>
849 * The function requires:
850 * %r4
851 */
852load_fpu_regs:
853 lg %r4,__LC_CURRENT
854 aghi %r4,__TASK_thread
855 TSTMSK __LC_CPU_FLAGS,_CIF_FPU
856 bnor %r14
857 lfpc __THREAD_FPU_fpc(%r4)
858 TSTMSK __LC_MACHINE_FLAGS,MACHINE_FLAG_VX
859 lg %r4,__THREAD_FPU_regs(%r4) # %r4 <- reg save area
860 jz .Lload_fpu_regs_fp # -> no VX, load FP regs
861 VLM %v0,%v15,0,%r4
862 VLM %v16,%v31,256,%r4
863 j .Lload_fpu_regs_done
864.Lload_fpu_regs_fp:
865 ld 0,0(%r4)
866 ld 1,8(%r4)
867 ld 2,16(%r4)
868 ld 3,24(%r4)
869 ld 4,32(%r4)
870 ld 5,40(%r4)
871 ld 6,48(%r4)
872 ld 7,56(%r4)
873 ld 8,64(%r4)
874 ld 9,72(%r4)
875 ld 10,80(%r4)
876 ld 11,88(%r4)
877 ld 12,96(%r4)
878 ld 13,104(%r4)
879 ld 14,112(%r4)
880 ld 15,120(%r4)
881.Lload_fpu_regs_done:
882 ni __LC_CPU_FLAGS+7,255-_CIF_FPU
883 br %r14
884.Lload_fpu_regs_end:
885
886.L__critical_end:
887
888/*
889 * Machine check handler routines
890 */
891ENTRY(mcck_int_handler)
892 STCK __LC_MCCK_CLOCK
893 la %r1,4095 # revalidate r1
894 spt __LC_CPU_TIMER_SAVE_AREA-4095(%r1) # revalidate cpu timer
895 lmg %r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r1)# revalidate gprs
896 lg %r10,__LC_LAST_BREAK
897 lg %r12,__LC_CURRENT
898 larl %r13,cleanup_critical
899 lmg %r8,%r9,__LC_MCK_OLD_PSW
900 TSTMSK __LC_MCCK_CODE,MCCK_CODE_SYSTEM_DAMAGE
901 jo .Lmcck_panic # yes -> rest of mcck code invalid
902 lghi %r14,__LC_CPU_TIMER_SAVE_AREA
903 mvc __LC_MCCK_ENTER_TIMER(8),0(%r14)
904 TSTMSK __LC_MCCK_CODE,MCCK_CODE_CPU_TIMER_VALID
905 jo 3f
906 la %r14,__LC_SYNC_ENTER_TIMER
907 clc 0(8,%r14),__LC_ASYNC_ENTER_TIMER
908 jl 0f
909 la %r14,__LC_ASYNC_ENTER_TIMER
9100: clc 0(8,%r14),__LC_EXIT_TIMER
911 jl 1f
912 la %r14,__LC_EXIT_TIMER
9131: clc 0(8,%r14),__LC_LAST_UPDATE_TIMER
914 jl 2f
915 la %r14,__LC_LAST_UPDATE_TIMER
9162: spt 0(%r14)
917 mvc __LC_MCCK_ENTER_TIMER(8),0(%r14)
9183: TSTMSK __LC_MCCK_CODE,(MCCK_CODE_PSW_MWP_VALID|MCCK_CODE_PSW_IA_VALID)
919 jno .Lmcck_panic # no -> skip cleanup critical
920 SWITCH_ASYNC __LC_GPREGS_SAVE_AREA+64,__LC_MCCK_ENTER_TIMER
921.Lmcck_skip:
922 lghi %r14,__LC_GPREGS_SAVE_AREA+64
923 stmg %r0,%r7,__PT_R0(%r11)
924 mvc __PT_R8(64,%r11),0(%r14)
925 stmg %r8,%r9,__PT_PSW(%r11)
926 xc __PT_FLAGS(8,%r11),__PT_FLAGS(%r11)
927 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
928 lgr %r2,%r11 # pass pointer to pt_regs
929 brasl %r14,s390_do_machine_check
930 tm __PT_PSW+1(%r11),0x01 # returning to user ?
931 jno .Lmcck_return
932 lg %r1,__LC_KERNEL_STACK # switch to kernel stack
933 mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
934 xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1)
935 la %r11,STACK_FRAME_OVERHEAD(%r1)
936 lgr %r15,%r1
937 ssm __LC_PGM_NEW_PSW # turn dat on, keep irqs off
938 TSTMSK __LC_CPU_FLAGS,_CIF_MCCK_PENDING
939 jno .Lmcck_return
940 TRACE_IRQS_OFF
941 brasl %r14,s390_handle_mcck
942 TRACE_IRQS_ON
943.Lmcck_return:
944 lg %r14,__LC_VDSO_PER_CPU
945 lmg %r0,%r10,__PT_R0(%r11)
946 mvc __LC_RETURN_MCCK_PSW(16),__PT_PSW(%r11) # move return PSW
947 tm __LC_RETURN_MCCK_PSW+1,0x01 # returning to user ?
948 jno 0f
949 stpt __LC_EXIT_TIMER
950 mvc __VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER
9510: lmg %r11,%r15,__PT_R11(%r11)
952 lpswe __LC_RETURN_MCCK_PSW
953
954.Lmcck_panic:
955 lg %r15,__LC_PANIC_STACK
956 la %r11,STACK_FRAME_OVERHEAD(%r15)
957 j .Lmcck_skip
958
959#
960# PSW restart interrupt handler
961#
962ENTRY(restart_int_handler)
963 TSTMSK __LC_MACHINE_FLAGS,MACHINE_FLAG_LPP
964 jz 0f
965 .insn s,0xb2800000,__LC_LPP
9660: stg %r15,__LC_SAVE_AREA_RESTART
967 lg %r15,__LC_RESTART_STACK
968 aghi %r15,-__PT_SIZE # create pt_regs on stack
969 xc 0(__PT_SIZE,%r15),0(%r15)
970 stmg %r0,%r14,__PT_R0(%r15)
971 mvc __PT_R15(8,%r15),__LC_SAVE_AREA_RESTART
972 mvc __PT_PSW(16,%r15),__LC_RST_OLD_PSW # store restart old psw
973 aghi %r15,-STACK_FRAME_OVERHEAD # create stack frame on stack
974 xc 0(STACK_FRAME_OVERHEAD,%r15),0(%r15)
975 lg %r1,__LC_RESTART_FN # load fn, parm & source cpu
976 lg %r2,__LC_RESTART_DATA
977 lg %r3,__LC_RESTART_SOURCE
978 ltgr %r3,%r3 # test source cpu address
979 jm 1f # negative -> skip source stop
9800: sigp %r4,%r3,SIGP_SENSE # sigp sense to source cpu
981 brc 10,0b # wait for status stored
9821: basr %r14,%r1 # call function
983 stap __SF_EMPTY(%r15) # store cpu address
984 llgh %r3,__SF_EMPTY(%r15)
9852: sigp %r4,%r3,SIGP_STOP # sigp stop to current cpu
986 brc 2,2b
9873: j 3b
988
989 .section .kprobes.text, "ax"
990
991#ifdef CONFIG_CHECK_STACK
992/*
993 * The synchronous or the asynchronous stack overflowed. We are dead.
994 * No need to properly save the registers, we are going to panic anyway.
995 * Setup a pt_regs so that show_trace can provide a good call trace.
996 */
997stack_overflow:
998 lg %r15,__LC_PANIC_STACK # change to panic stack
999 la %r11,STACK_FRAME_OVERHEAD(%r15)
1000 stmg %r0,%r7,__PT_R0(%r11)
1001 stmg %r8,%r9,__PT_PSW(%r11)
1002 mvc __PT_R8(64,%r11),0(%r14)
1003 stg %r10,__PT_ORIG_GPR2(%r11) # store last break to orig_gpr2
1004 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
1005 lgr %r2,%r11 # pass pointer to pt_regs
1006 jg kernel_stack_overflow
1007#endif
1008
1009cleanup_critical:
1010#if IS_ENABLED(CONFIG_KVM)
1011 clg %r9,BASED(.Lcleanup_table_sie) # .Lsie_gmap
1012 jl 0f
1013 clg %r9,BASED(.Lcleanup_table_sie+8)# .Lsie_done
1014 jl .Lcleanup_sie
1015#endif
1016 clg %r9,BASED(.Lcleanup_table) # system_call
1017 jl 0f
1018 clg %r9,BASED(.Lcleanup_table+8) # .Lsysc_do_svc
1019 jl .Lcleanup_system_call
1020 clg %r9,BASED(.Lcleanup_table+16) # .Lsysc_tif
1021 jl 0f
1022 clg %r9,BASED(.Lcleanup_table+24) # .Lsysc_restore
1023 jl .Lcleanup_sysc_tif
1024 clg %r9,BASED(.Lcleanup_table+32) # .Lsysc_done
1025 jl .Lcleanup_sysc_restore
1026 clg %r9,BASED(.Lcleanup_table+40) # .Lio_tif
1027 jl 0f
1028 clg %r9,BASED(.Lcleanup_table+48) # .Lio_restore
1029 jl .Lcleanup_io_tif
1030 clg %r9,BASED(.Lcleanup_table+56) # .Lio_done
1031 jl .Lcleanup_io_restore
1032 clg %r9,BASED(.Lcleanup_table+64) # psw_idle
1033 jl 0f
1034 clg %r9,BASED(.Lcleanup_table+72) # .Lpsw_idle_end
1035 jl .Lcleanup_idle
1036 clg %r9,BASED(.Lcleanup_table+80) # save_fpu_regs
1037 jl 0f
1038 clg %r9,BASED(.Lcleanup_table+88) # .Lsave_fpu_regs_end
1039 jl .Lcleanup_save_fpu_regs
1040 clg %r9,BASED(.Lcleanup_table+96) # load_fpu_regs
1041 jl 0f
1042 clg %r9,BASED(.Lcleanup_table+104) # .Lload_fpu_regs_end
1043 jl .Lcleanup_load_fpu_regs
10440: br %r14
1045
1046 .align 8
1047.Lcleanup_table:
1048 .quad system_call
1049 .quad .Lsysc_do_svc
1050 .quad .Lsysc_tif
1051 .quad .Lsysc_restore
1052 .quad .Lsysc_done
1053 .quad .Lio_tif
1054 .quad .Lio_restore
1055 .quad .Lio_done
1056 .quad psw_idle
1057 .quad .Lpsw_idle_end
1058 .quad save_fpu_regs
1059 .quad .Lsave_fpu_regs_end
1060 .quad load_fpu_regs
1061 .quad .Lload_fpu_regs_end
1062
1063#if IS_ENABLED(CONFIG_KVM)
1064.Lcleanup_table_sie:
1065 .quad .Lsie_gmap
1066 .quad .Lsie_done
1067
1068.Lcleanup_sie:
1069 lg %r9,__SF_EMPTY(%r15) # get control block pointer
1070 ni __SIE_PROG0C+3(%r9),0xfe # no longer in SIE
1071 lctlg %c1,%c1,__LC_USER_ASCE # load primary asce
1072 larl %r9,sie_exit # skip forward to sie_exit
1073 br %r14
1074#endif
1075
1076.Lcleanup_system_call:
1077 # check if stpt has been executed
1078 clg %r9,BASED(.Lcleanup_system_call_insn)
1079 jh 0f
1080 mvc __LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER
1081 cghi %r11,__LC_SAVE_AREA_ASYNC
1082 je 0f
1083 mvc __LC_SYNC_ENTER_TIMER(8),__LC_MCCK_ENTER_TIMER
10840: # check if stmg has been executed
1085 clg %r9,BASED(.Lcleanup_system_call_insn+8)
1086 jh 0f
1087 mvc __LC_SAVE_AREA_SYNC(64),0(%r11)
10880: # check if base register setup + TIF bit load has been done
1089 clg %r9,BASED(.Lcleanup_system_call_insn+16)
1090 jhe 0f
1091 # set up saved registers r10 and r12
1092 stg %r10,16(%r11) # r10 last break
1093 stg %r12,32(%r11) # r12 task struct pointer
10940: # check if the user time update has been done
1095 clg %r9,BASED(.Lcleanup_system_call_insn+24)
1096 jh 0f
1097 lg %r15,__LC_EXIT_TIMER
1098 slg %r15,__LC_SYNC_ENTER_TIMER
1099 alg %r15,__LC_USER_TIMER
1100 stg %r15,__LC_USER_TIMER
11010: # check if the system time update has been done
1102 clg %r9,BASED(.Lcleanup_system_call_insn+32)
1103 jh 0f
1104 lg %r15,__LC_LAST_UPDATE_TIMER
1105 slg %r15,__LC_EXIT_TIMER
1106 alg %r15,__LC_SYSTEM_TIMER
1107 stg %r15,__LC_SYSTEM_TIMER
11080: # update accounting time stamp
1109 mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
1110 # do LAST_BREAK
1111 lg %r9,16(%r11)
1112 srag %r9,%r9,23
1113 jz 0f
1114 lgr %r9,%r12
1115 aghi %r9,__TASK_thread
1116 mvc __THREAD_last_break(8,%r9),16(%r11)
11170: # set up saved register r11
1118 lg %r15,__LC_KERNEL_STACK
1119 la %r9,STACK_FRAME_OVERHEAD(%r15)
1120 stg %r9,24(%r11) # r11 pt_regs pointer
1121 # fill pt_regs
1122 mvc __PT_R8(64,%r9),__LC_SAVE_AREA_SYNC
1123 stmg %r0,%r7,__PT_R0(%r9)
1124 mvc __PT_PSW(16,%r9),__LC_SVC_OLD_PSW
1125 mvc __PT_INT_CODE(4,%r9),__LC_SVC_ILC
1126 xc __PT_FLAGS(8,%r9),__PT_FLAGS(%r9)
1127 mvi __PT_FLAGS+7(%r9),_PIF_SYSCALL
1128 # setup saved register r15
1129 stg %r15,56(%r11) # r15 stack pointer
1130 # set new psw address and exit
1131 larl %r9,.Lsysc_do_svc
1132 br %r14
1133.Lcleanup_system_call_insn:
1134 .quad system_call
1135 .quad .Lsysc_stmg
1136 .quad .Lsysc_per
1137 .quad .Lsysc_vtime+36
1138 .quad .Lsysc_vtime+42
1139
1140.Lcleanup_sysc_tif:
1141 larl %r9,.Lsysc_tif
1142 br %r14
1143
1144.Lcleanup_sysc_restore:
1145 clg %r9,BASED(.Lcleanup_sysc_restore_insn)
1146 je 0f
1147 lg %r9,24(%r11) # get saved pointer to pt_regs
1148 mvc __LC_RETURN_PSW(16),__PT_PSW(%r9)
1149 mvc 0(64,%r11),__PT_R8(%r9)
1150 lmg %r0,%r7,__PT_R0(%r9)
11510: lmg %r8,%r9,__LC_RETURN_PSW
1152 br %r14
1153.Lcleanup_sysc_restore_insn:
1154 .quad .Lsysc_done - 4
1155
1156.Lcleanup_io_tif:
1157 larl %r9,.Lio_tif
1158 br %r14
1159
1160.Lcleanup_io_restore:
1161 clg %r9,BASED(.Lcleanup_io_restore_insn)
1162 je 0f
1163 lg %r9,24(%r11) # get saved r11 pointer to pt_regs
1164 mvc __LC_RETURN_PSW(16),__PT_PSW(%r9)
1165 mvc 0(64,%r11),__PT_R8(%r9)
1166 lmg %r0,%r7,__PT_R0(%r9)
11670: lmg %r8,%r9,__LC_RETURN_PSW
1168 br %r14
1169.Lcleanup_io_restore_insn:
1170 .quad .Lio_done - 4
1171
1172.Lcleanup_idle:
1173 ni __LC_CPU_FLAGS+7,255-_CIF_ENABLED_WAIT
1174 # copy interrupt clock & cpu timer
1175 mvc __CLOCK_IDLE_EXIT(8,%r2),__LC_INT_CLOCK
1176 mvc __TIMER_IDLE_EXIT(8,%r2),__LC_ASYNC_ENTER_TIMER
1177 cghi %r11,__LC_SAVE_AREA_ASYNC
1178 je 0f
1179 mvc __CLOCK_IDLE_EXIT(8,%r2),__LC_MCCK_CLOCK
1180 mvc __TIMER_IDLE_EXIT(8,%r2),__LC_MCCK_ENTER_TIMER
11810: # check if stck & stpt have been executed
1182 clg %r9,BASED(.Lcleanup_idle_insn)
1183 jhe 1f
1184 mvc __CLOCK_IDLE_ENTER(8,%r2),__CLOCK_IDLE_EXIT(%r2)
1185 mvc __TIMER_IDLE_ENTER(8,%r2),__TIMER_IDLE_EXIT(%r2)
11861: # calculate idle cycles
1187#ifdef CONFIG_SMP
1188 clg %r9,BASED(.Lcleanup_idle_insn)
1189 jl 3f
1190 larl %r1,smp_cpu_mtid
1191 llgf %r1,0(%r1)
1192 ltgr %r1,%r1
1193 jz 3f
1194 .insn rsy,0xeb0000000017,%r1,5,__SF_EMPTY+80(%r15)
1195 larl %r3,mt_cycles
1196 ag %r3,__LC_PERCPU_OFFSET
1197 la %r4,__SF_EMPTY+16(%r15)
11982: lg %r0,0(%r3)
1199 slg %r0,0(%r4)
1200 alg %r0,64(%r4)
1201 stg %r0,0(%r3)
1202 la %r3,8(%r3)
1203 la %r4,8(%r4)
1204 brct %r1,2b
1205#endif
12063: # account system time going idle
1207 lg %r9,__LC_STEAL_TIMER
1208 alg %r9,__CLOCK_IDLE_ENTER(%r2)
1209 slg %r9,__LC_LAST_UPDATE_CLOCK
1210 stg %r9,__LC_STEAL_TIMER
1211 mvc __LC_LAST_UPDATE_CLOCK(8),__CLOCK_IDLE_EXIT(%r2)
1212 lg %r9,__LC_SYSTEM_TIMER
1213 alg %r9,__LC_LAST_UPDATE_TIMER
1214 slg %r9,__TIMER_IDLE_ENTER(%r2)
1215 stg %r9,__LC_SYSTEM_TIMER
1216 mvc __LC_LAST_UPDATE_TIMER(8),__TIMER_IDLE_EXIT(%r2)
1217 # prepare return psw
1218 nihh %r8,0xfcfd # clear irq & wait state bits
1219 lg %r9,48(%r11) # return from psw_idle
1220 br %r14
1221.Lcleanup_idle_insn:
1222 .quad .Lpsw_idle_lpsw
1223
1224.Lcleanup_save_fpu_regs:
1225 larl %r9,save_fpu_regs
1226 br %r14
1227
1228.Lcleanup_load_fpu_regs:
1229 larl %r9,load_fpu_regs
1230 br %r14
1231
1232/*
1233 * Integer constants
1234 */
1235 .align 8
1236.Lcritical_start:
1237 .quad .L__critical_start
1238.Lcritical_length:
1239 .quad .L__critical_end - .L__critical_start
1240#if IS_ENABLED(CONFIG_KVM)
1241.Lsie_critical_start:
1242 .quad .Lsie_gmap
1243.Lsie_critical_length:
1244 .quad .Lsie_done - .Lsie_gmap
1245#endif
1246
1247 .section .rodata, "a"
1248#define SYSCALL(esame,emu) .long esame
1249 .globl sys_call_table
1250sys_call_table:
1251#include "syscalls.S"
1252#undef SYSCALL
1253
1254#ifdef CONFIG_COMPAT
1255
1256#define SYSCALL(esame,emu) .long emu
1257 .globl sys_call_table_emu
1258sys_call_table_emu:
1259#include "syscalls.S"
1260#undef SYSCALL
1261#endif
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 */
10
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>
22
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
39
40_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
41 _TIF_MCCK_PENDING | _TIF_PER_TRAP | _TIF_ASCE)
42_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
43 _TIF_MCCK_PENDING | _TIF_ASCE)
44_TIF_TRACE = (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | \
45 _TIF_SYSCALL_TRACEPOINT)
46_TIF_TRANSFER = (_TIF_MCCK_PENDING | _TIF_TLB_WAIT)
47
48STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
49STACK_SIZE = 1 << STACK_SHIFT
50STACK_INIT = STACK_SIZE - STACK_FRAME_OVERHEAD - __PT_SIZE
51
52#define BASED(name) name-system_call(%r13)
53
54 .macro TRACE_IRQS_ON
55#ifdef CONFIG_TRACE_IRQFLAGS
56 basr %r2,%r0
57 l %r1,BASED(.Lhardirqs_on)
58 basr %r14,%r1 # call trace_hardirqs_on_caller
59#endif
60 .endm
61
62 .macro TRACE_IRQS_OFF
63#ifdef CONFIG_TRACE_IRQFLAGS
64 basr %r2,%r0
65 l %r1,BASED(.Lhardirqs_off)
66 basr %r14,%r1 # call trace_hardirqs_off_caller
67#endif
68 .endm
69
70 .macro LOCKDEP_SYS_EXIT
71#ifdef CONFIG_LOCKDEP
72 tm __PT_PSW+1(%r11),0x01 # returning to user ?
73 jz .+10
74 l %r1,BASED(.Llockdep_sys_exit)
75 basr %r14,%r1 # call lockdep_sys_exit
76#endif
77 .endm
78
79 .macro CHECK_STACK stacksize,savearea
80#ifdef CONFIG_CHECK_STACK
81 tml %r15,\stacksize - CONFIG_STACK_GUARD
82 la %r14,\savearea
83 jz stack_overflow
84#endif
85 .endm
86
87 .macro SWITCH_ASYNC savearea,stack,shift
88 tmh %r8,0x0001 # interrupting from user ?
89 jnz 1f
90 lr %r14,%r9
91 sl %r14,BASED(.Lcritical_start)
92 cl %r14,BASED(.Lcritical_length)
93 jhe 0f
94 la %r11,\savearea # inside critical section, do cleanup
95 bras %r14,cleanup_critical
96 tmh %r8,0x0001 # retest problem state after cleanup
97 jnz 1f
980: l %r14,\stack # are we already on the target stack?
99 slr %r14,%r15
100 sra %r14,\shift
101 jnz 1f
102 CHECK_STACK 1<<\shift,\savearea
103 ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
104 j 2f
1051: l %r15,\stack # load target stack
1062: la %r11,STACK_FRAME_OVERHEAD(%r15)
107 .endm
108
109 .macro ADD64 high,low,timer
110 al \high,\timer
111 al \low,4+\timer
112 brc 12,.+8
113 ahi \high,1
114 .endm
115
116 .macro SUB64 high,low,timer
117 sl \high,\timer
118 sl \low,4+\timer
119 brc 3,.+8
120 ahi \high,-1
121 .endm
122
123 .macro UPDATE_VTIME high,low,enter_timer
124 lm \high,\low,__LC_EXIT_TIMER
125 SUB64 \high,\low,\enter_timer
126 ADD64 \high,\low,__LC_USER_TIMER
127 stm \high,\low,__LC_USER_TIMER
128 lm \high,\low,__LC_LAST_UPDATE_TIMER
129 SUB64 \high,\low,__LC_EXIT_TIMER
130 ADD64 \high,\low,__LC_SYSTEM_TIMER
131 stm \high,\low,__LC_SYSTEM_TIMER
132 mvc __LC_LAST_UPDATE_TIMER(8),\enter_timer
133 .endm
134
135 .macro REENABLE_IRQS
136 st %r8,__LC_RETURN_PSW
137 ni __LC_RETURN_PSW,0xbf
138 ssm __LC_RETURN_PSW
139 .endm
140
141 .section .kprobes.text, "ax"
142
143/*
144 * Scheduler resume function, called by switch_to
145 * gpr2 = (task_struct *) prev
146 * gpr3 = (task_struct *) next
147 * Returns:
148 * gpr2 = prev
149 */
150ENTRY(__switch_to)
151 stm %r6,%r15,__SF_GPRS(%r15) # store gprs of prev task
152 st %r15,__THREAD_ksp(%r2) # store kernel stack of prev
153 l %r4,__THREAD_info(%r2) # get thread_info of prev
154 l %r5,__THREAD_info(%r3) # get thread_info of next
155 lr %r15,%r5
156 ahi %r15,STACK_INIT # end of kernel stack of next
157 st %r3,__LC_CURRENT # store task struct of next
158 st %r5,__LC_THREAD_INFO # store thread info of next
159 st %r15,__LC_KERNEL_STACK # store end of kernel stack
160 lctl %c4,%c4,__TASK_pid(%r3) # load pid to control reg. 4
161 mvc __LC_CURRENT_PID(4,%r0),__TASK_pid(%r3) # store pid of next
162 l %r15,__THREAD_ksp(%r3) # load kernel stack of next
163 lhi %r6,_TIF_TRANSFER # transfer TIF bits
164 n %r6,__TI_flags(%r4) # isolate TIF bits
165 jz 0f
166 o %r6,__TI_flags(%r5) # set TIF bits of next
167 st %r6,__TI_flags(%r5)
168 ni __TI_flags+3(%r4),255-_TIF_TRANSFER # clear TIF bits of prev
1690: lm %r6,%r15,__SF_GPRS(%r15) # load gprs of next task
170 br %r14
171
172__critical_start:
173/*
174 * SVC interrupt handler routine. System calls are synchronous events and
175 * are executed with interrupts enabled.
176 */
177
178ENTRY(system_call)
179 stpt __LC_SYNC_ENTER_TIMER
180sysc_stm:
181 stm %r8,%r15,__LC_SAVE_AREA_SYNC
182 l %r12,__LC_THREAD_INFO
183 l %r13,__LC_SVC_NEW_PSW+4
184sysc_per:
185 l %r15,__LC_KERNEL_STACK
186 la %r11,STACK_FRAME_OVERHEAD(%r15) # pointer to pt_regs
187sysc_vtime:
188 UPDATE_VTIME %r8,%r9,__LC_SYNC_ENTER_TIMER
189 stm %r0,%r7,__PT_R0(%r11)
190 mvc __PT_R8(32,%r11),__LC_SAVE_AREA_SYNC
191 mvc __PT_PSW(8,%r11),__LC_SVC_OLD_PSW
192 mvc __PT_INT_CODE(4,%r11),__LC_SVC_ILC
193sysc_do_svc:
194 oi __TI_flags+3(%r12),_TIF_SYSCALL
195 l %r10,__TI_sysc_table(%r12) # 31 bit system call table
196 lh %r8,__PT_INT_CODE+2(%r11)
197 sla %r8,2 # shift and test for svc0
198 jnz sysc_nr_ok
199 # svc 0: system call number in %r1
200 cl %r1,BASED(.Lnr_syscalls)
201 jnl sysc_nr_ok
202 sth %r1,__PT_INT_CODE+2(%r11)
203 lr %r8,%r1
204 sla %r8,2
205sysc_nr_ok:
206 xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
207 st %r2,__PT_ORIG_GPR2(%r11)
208 st %r7,STACK_FRAME_OVERHEAD(%r15)
209 l %r9,0(%r8,%r10) # get system call addr.
210 tm __TI_flags+2(%r12),_TIF_TRACE >> 8
211 jnz sysc_tracesys
212 basr %r14,%r9 # call sys_xxxx
213 st %r2,__PT_R2(%r11) # store return value
214
215sysc_return:
216 LOCKDEP_SYS_EXIT
217sysc_tif:
218 tm __PT_PSW+1(%r11),0x01 # returning to user ?
219 jno sysc_restore
220 tm __TI_flags+3(%r12),_TIF_WORK_SVC
221 jnz sysc_work # check for work
222 ni __TI_flags+3(%r12),255-_TIF_SYSCALL
223sysc_restore:
224 mvc __LC_RETURN_PSW(8),__PT_PSW(%r11)
225 stpt __LC_EXIT_TIMER
226 lm %r0,%r15,__PT_R0(%r11)
227 lpsw __LC_RETURN_PSW
228sysc_done:
229
230#
231# One of the work bits is on. Find out which one.
232#
233sysc_work:
234 tm __TI_flags+3(%r12),_TIF_MCCK_PENDING
235 jo sysc_mcck_pending
236 tm __TI_flags+3(%r12),_TIF_NEED_RESCHED
237 jo sysc_reschedule
238 tm __TI_flags+3(%r12),_TIF_PER_TRAP
239 jo sysc_singlestep
240 tm __TI_flags+3(%r12),_TIF_SIGPENDING
241 jo sysc_sigpending
242 tm __TI_flags+3(%r12),_TIF_NOTIFY_RESUME
243 jo sysc_notify_resume
244 tm __TI_flags+3(%r12),_TIF_ASCE
245 jo sysc_uaccess
246 j sysc_return # beware of critical section cleanup
247
248#
249# _TIF_NEED_RESCHED is set, call schedule
250#
251sysc_reschedule:
252 l %r1,BASED(.Lschedule)
253 la %r14,BASED(sysc_return)
254 br %r1 # call schedule
255
256#
257# _TIF_MCCK_PENDING is set, call handler
258#
259sysc_mcck_pending:
260 l %r1,BASED(.Lhandle_mcck)
261 la %r14,BASED(sysc_return)
262 br %r1 # TIF bit will be cleared by handler
263
264#
265# _TIF_ASCE is set, load user space asce
266#
267sysc_uaccess:
268 ni __TI_flags+3(%r12),255-_TIF_ASCE
269 lctl %c1,%c1,__LC_USER_ASCE # load primary asce
270 j sysc_return
271
272#
273# _TIF_SIGPENDING is set, call do_signal
274#
275sysc_sigpending:
276 lr %r2,%r11 # pass pointer to pt_regs
277 l %r1,BASED(.Ldo_signal)
278 basr %r14,%r1 # call do_signal
279 tm __TI_flags+3(%r12),_TIF_SYSCALL
280 jno sysc_return
281 lm %r2,%r7,__PT_R2(%r11) # load svc arguments
282 l %r10,__TI_sysc_table(%r12) # 31 bit system call table
283 xr %r8,%r8 # svc 0 returns -ENOSYS
284 clc __PT_INT_CODE+2(2,%r11),BASED(.Lnr_syscalls+2)
285 jnl sysc_nr_ok # invalid svc number -> do svc 0
286 lh %r8,__PT_INT_CODE+2(%r11) # load new svc number
287 sla %r8,2
288 j sysc_nr_ok # restart svc
289
290#
291# _TIF_NOTIFY_RESUME is set, call do_notify_resume
292#
293sysc_notify_resume:
294 lr %r2,%r11 # pass pointer to pt_regs
295 l %r1,BASED(.Ldo_notify_resume)
296 la %r14,BASED(sysc_return)
297 br %r1 # call do_notify_resume
298
299#
300# _TIF_PER_TRAP is set, call do_per_trap
301#
302sysc_singlestep:
303 ni __TI_flags+3(%r12),255-_TIF_PER_TRAP
304 lr %r2,%r11 # pass pointer to pt_regs
305 l %r1,BASED(.Ldo_per_trap)
306 la %r14,BASED(sysc_return)
307 br %r1 # call do_per_trap
308
309#
310# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
311# and after the system call
312#
313sysc_tracesys:
314 l %r1,BASED(.Ltrace_enter)
315 lr %r2,%r11 # pass pointer to pt_regs
316 la %r3,0
317 xr %r0,%r0
318 icm %r0,3,__PT_INT_CODE+2(%r11)
319 st %r0,__PT_R2(%r11)
320 basr %r14,%r1 # call do_syscall_trace_enter
321 cl %r2,BASED(.Lnr_syscalls)
322 jnl sysc_tracenogo
323 lr %r8,%r2
324 sll %r8,2
325 l %r9,0(%r8,%r10)
326sysc_tracego:
327 lm %r3,%r7,__PT_R3(%r11)
328 st %r7,STACK_FRAME_OVERHEAD(%r15)
329 l %r2,__PT_ORIG_GPR2(%r11)
330 basr %r14,%r9 # call sys_xxx
331 st %r2,__PT_R2(%r11) # store return value
332sysc_tracenogo:
333 tm __TI_flags+2(%r12),_TIF_TRACE >> 8
334 jz sysc_return
335 l %r1,BASED(.Ltrace_exit)
336 lr %r2,%r11 # pass pointer to pt_regs
337 la %r14,BASED(sysc_return)
338 br %r1 # call do_syscall_trace_exit
339
340#
341# a new process exits the kernel with ret_from_fork
342#
343ENTRY(ret_from_fork)
344 la %r11,STACK_FRAME_OVERHEAD(%r15)
345 l %r12,__LC_THREAD_INFO
346 l %r13,__LC_SVC_NEW_PSW+4
347 l %r1,BASED(.Lschedule_tail)
348 basr %r14,%r1 # call schedule_tail
349 TRACE_IRQS_ON
350 ssm __LC_SVC_NEW_PSW # reenable interrupts
351 tm __PT_PSW+1(%r11),0x01 # forking a kernel thread ?
352 jne sysc_tracenogo
353 # it's a kernel thread
354 lm %r9,%r10,__PT_R9(%r11) # load gprs
355ENTRY(kernel_thread_starter)
356 la %r2,0(%r10)
357 basr %r14,%r9
358 j sysc_tracenogo
359
360/*
361 * Program check handler routine
362 */
363
364ENTRY(pgm_check_handler)
365 stpt __LC_SYNC_ENTER_TIMER
366 stm %r8,%r15,__LC_SAVE_AREA_SYNC
367 l %r12,__LC_THREAD_INFO
368 l %r13,__LC_SVC_NEW_PSW+4
369 lm %r8,%r9,__LC_PGM_OLD_PSW
370 tmh %r8,0x0001 # test problem state bit
371 jnz 1f # -> fault in user space
372 tmh %r8,0x4000 # PER bit set in old PSW ?
373 jnz 0f # -> enabled, can't be a double fault
374 tm __LC_PGM_ILC+3,0x80 # check for per exception
375 jnz pgm_svcper # -> single stepped svc
3760: CHECK_STACK STACK_SIZE,__LC_SAVE_AREA_SYNC
377 ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
378 j 2f
3791: UPDATE_VTIME %r14,%r15,__LC_SYNC_ENTER_TIMER
380 l %r15,__LC_KERNEL_STACK
3812: la %r11,STACK_FRAME_OVERHEAD(%r15)
382 stm %r0,%r7,__PT_R0(%r11)
383 mvc __PT_R8(32,%r11),__LC_SAVE_AREA_SYNC
384 stm %r8,%r9,__PT_PSW(%r11)
385 mvc __PT_INT_CODE(4,%r11),__LC_PGM_ILC
386 mvc __PT_INT_PARM_LONG(4,%r11),__LC_TRANS_EXC_CODE
387 tm __LC_PGM_ILC+3,0x80 # check for per exception
388 jz 0f
389 l %r1,__TI_task(%r12)
390 tmh %r8,0x0001 # kernel per event ?
391 jz pgm_kprobe
392 oi __TI_flags+3(%r12),_TIF_PER_TRAP
393 mvc __THREAD_per_address(4,%r1),__LC_PER_ADDRESS
394 mvc __THREAD_per_cause(2,%r1),__LC_PER_CAUSE
395 mvc __THREAD_per_paid(1,%r1),__LC_PER_PAID
3960: REENABLE_IRQS
397 xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
398 l %r1,BASED(.Ljump_table)
399 la %r10,0x7f
400 n %r10,__PT_INT_CODE(%r11)
401 je sysc_return
402 sll %r10,2
403 l %r1,0(%r10,%r1) # load address of handler routine
404 lr %r2,%r11 # pass pointer to pt_regs
405 basr %r14,%r1 # branch to interrupt-handler
406 j sysc_return
407
408#
409# PER event in supervisor state, must be kprobes
410#
411pgm_kprobe:
412 REENABLE_IRQS
413 xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
414 l %r1,BASED(.Ldo_per_trap)
415 lr %r2,%r11 # pass pointer to pt_regs
416 basr %r14,%r1 # call do_per_trap
417 j sysc_return
418
419#
420# single stepped system call
421#
422pgm_svcper:
423 oi __TI_flags+3(%r12),_TIF_PER_TRAP
424 mvc __LC_RETURN_PSW(4),__LC_SVC_NEW_PSW
425 mvc __LC_RETURN_PSW+4(4),BASED(.Lsysc_per)
426 lpsw __LC_RETURN_PSW # branch to sysc_per and enable irqs
427
428/*
429 * IO interrupt handler routine
430 */
431
432ENTRY(io_int_handler)
433 stck __LC_INT_CLOCK
434 stpt __LC_ASYNC_ENTER_TIMER
435 stm %r8,%r15,__LC_SAVE_AREA_ASYNC
436 l %r12,__LC_THREAD_INFO
437 l %r13,__LC_SVC_NEW_PSW+4
438 lm %r8,%r9,__LC_IO_OLD_PSW
439 tmh %r8,0x0001 # interrupting from user ?
440 jz io_skip
441 UPDATE_VTIME %r14,%r15,__LC_ASYNC_ENTER_TIMER
442io_skip:
443 SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT
444 stm %r0,%r7,__PT_R0(%r11)
445 mvc __PT_R8(32,%r11),__LC_SAVE_AREA_ASYNC
446 stm %r8,%r9,__PT_PSW(%r11)
447 mvc __PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID
448 TRACE_IRQS_OFF
449 xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
450io_loop:
451 l %r1,BASED(.Ldo_IRQ)
452 lr %r2,%r11 # pass pointer to pt_regs
453 lhi %r3,IO_INTERRUPT
454 tm __PT_INT_CODE+8(%r11),0x80 # adapter interrupt ?
455 jz io_call
456 lhi %r3,THIN_INTERRUPT
457io_call:
458 basr %r14,%r1 # call do_IRQ
459 tm __LC_MACHINE_FLAGS+2,0x10 # MACHINE_FLAG_LPAR
460 jz io_return
461 tpi 0
462 jz io_return
463 mvc __PT_INT_CODE(12,%r11),__LC_SUBCHANNEL_ID
464 j io_loop
465io_return:
466 LOCKDEP_SYS_EXIT
467 TRACE_IRQS_ON
468io_tif:
469 tm __TI_flags+3(%r12),_TIF_WORK_INT
470 jnz io_work # there is work to do (signals etc.)
471io_restore:
472 mvc __LC_RETURN_PSW(8),__PT_PSW(%r11)
473 stpt __LC_EXIT_TIMER
474 lm %r0,%r15,__PT_R0(%r11)
475 lpsw __LC_RETURN_PSW
476io_done:
477
478#
479# There is work todo, find out in which context we have been interrupted:
480# 1) if we return to user space we can do all _TIF_WORK_INT work
481# 2) if we return to kernel code and preemptive scheduling is enabled check
482# the preemption counter and if it is zero call preempt_schedule_irq
483# Before any work can be done, a switch to the kernel stack is required.
484#
485io_work:
486 tm __PT_PSW+1(%r11),0x01 # returning to user ?
487 jo io_work_user # yes -> do resched & signal
488#ifdef CONFIG_PREEMPT
489 # check for preemptive scheduling
490 icm %r0,15,__TI_precount(%r12)
491 jnz io_restore # preemption disabled
492 tm __TI_flags+3(%r12),_TIF_NEED_RESCHED
493 jno io_restore
494 # switch to kernel stack
495 l %r1,__PT_R15(%r11)
496 ahi %r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
497 mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
498 xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1)
499 la %r11,STACK_FRAME_OVERHEAD(%r1)
500 lr %r15,%r1
501 # TRACE_IRQS_ON already done at io_return, call
502 # TRACE_IRQS_OFF to keep things symmetrical
503 TRACE_IRQS_OFF
504 l %r1,BASED(.Lpreempt_irq)
505 basr %r14,%r1 # call preempt_schedule_irq
506 j io_return
507#else
508 j io_restore
509#endif
510
511#
512# Need to do work before returning to userspace, switch to kernel stack
513#
514io_work_user:
515 l %r1,__LC_KERNEL_STACK
516 mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
517 xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1)
518 la %r11,STACK_FRAME_OVERHEAD(%r1)
519 lr %r15,%r1
520
521#
522# One of the work bits is on. Find out which one.
523# Checked are: _TIF_SIGPENDING, _TIF_NOTIFY_RESUME, _TIF_NEED_RESCHED
524# and _TIF_MCCK_PENDING
525#
526io_work_tif:
527 tm __TI_flags+3(%r12),_TIF_MCCK_PENDING
528 jo io_mcck_pending
529 tm __TI_flags+3(%r12),_TIF_NEED_RESCHED
530 jo io_reschedule
531 tm __TI_flags+3(%r12),_TIF_SIGPENDING
532 jo io_sigpending
533 tm __TI_flags+3(%r12),_TIF_NOTIFY_RESUME
534 jo io_notify_resume
535 tm __TI_flags+3(%r12),_TIF_ASCE
536 jo io_uaccess
537 j io_return # beware of critical section cleanup
538
539#
540# _TIF_MCCK_PENDING is set, call handler
541#
542io_mcck_pending:
543 # TRACE_IRQS_ON already done at io_return
544 l %r1,BASED(.Lhandle_mcck)
545 basr %r14,%r1 # TIF bit will be cleared by handler
546 TRACE_IRQS_OFF
547 j io_return
548
549#
550# _TIF_ASCE is set, load user space asce
551#
552io_uaccess:
553 ni __TI_flags+3(%r12),255-_TIF_ASCE
554 lctl %c1,%c1,__LC_USER_ASCE # load primary asce
555 j io_return
556
557#
558# _TIF_NEED_RESCHED is set, call schedule
559#
560io_reschedule:
561 # TRACE_IRQS_ON already done at io_return
562 l %r1,BASED(.Lschedule)
563 ssm __LC_SVC_NEW_PSW # reenable interrupts
564 basr %r14,%r1 # call scheduler
565 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
566 TRACE_IRQS_OFF
567 j io_return
568
569#
570# _TIF_SIGPENDING is set, call do_signal
571#
572io_sigpending:
573 # TRACE_IRQS_ON already done at io_return
574 l %r1,BASED(.Ldo_signal)
575 ssm __LC_SVC_NEW_PSW # reenable interrupts
576 lr %r2,%r11 # pass pointer to pt_regs
577 basr %r14,%r1 # call do_signal
578 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
579 TRACE_IRQS_OFF
580 j io_return
581
582#
583# _TIF_SIGPENDING is set, call do_signal
584#
585io_notify_resume:
586 # TRACE_IRQS_ON already done at io_return
587 l %r1,BASED(.Ldo_notify_resume)
588 ssm __LC_SVC_NEW_PSW # reenable interrupts
589 lr %r2,%r11 # pass pointer to pt_regs
590 basr %r14,%r1 # call do_notify_resume
591 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
592 TRACE_IRQS_OFF
593 j io_return
594
595/*
596 * External interrupt handler routine
597 */
598
599ENTRY(ext_int_handler)
600 stck __LC_INT_CLOCK
601 stpt __LC_ASYNC_ENTER_TIMER
602 stm %r8,%r15,__LC_SAVE_AREA_ASYNC
603 l %r12,__LC_THREAD_INFO
604 l %r13,__LC_SVC_NEW_PSW+4
605 lm %r8,%r9,__LC_EXT_OLD_PSW
606 tmh %r8,0x0001 # interrupting from user ?
607 jz ext_skip
608 UPDATE_VTIME %r14,%r15,__LC_ASYNC_ENTER_TIMER
609ext_skip:
610 SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT
611 stm %r0,%r7,__PT_R0(%r11)
612 mvc __PT_R8(32,%r11),__LC_SAVE_AREA_ASYNC
613 stm %r8,%r9,__PT_PSW(%r11)
614 mvc __PT_INT_CODE(4,%r11),__LC_EXT_CPU_ADDR
615 mvc __PT_INT_PARM(4,%r11),__LC_EXT_PARAMS
616 TRACE_IRQS_OFF
617 l %r1,BASED(.Ldo_IRQ)
618 lr %r2,%r11 # pass pointer to pt_regs
619 lhi %r3,EXT_INTERRUPT
620 basr %r14,%r1 # call do_IRQ
621 j io_return
622
623/*
624 * Load idle PSW. The second "half" of this function is in cleanup_idle.
625 */
626ENTRY(psw_idle)
627 st %r3,__SF_EMPTY(%r15)
628 basr %r1,0
629 la %r1,psw_idle_lpsw+4-.(%r1)
630 st %r1,__SF_EMPTY+4(%r15)
631 oi __SF_EMPTY+4(%r15),0x80
632 stck __CLOCK_IDLE_ENTER(%r2)
633 stpt __TIMER_IDLE_ENTER(%r2)
634psw_idle_lpsw:
635 lpsw __SF_EMPTY(%r15)
636 br %r14
637psw_idle_end:
638
639__critical_end:
640
641/*
642 * Machine check handler routines
643 */
644
645ENTRY(mcck_int_handler)
646 stck __LC_MCCK_CLOCK
647 spt __LC_CPU_TIMER_SAVE_AREA # revalidate cpu timer
648 lm %r0,%r15,__LC_GPREGS_SAVE_AREA # revalidate gprs
649 l %r12,__LC_THREAD_INFO
650 l %r13,__LC_SVC_NEW_PSW+4
651 lm %r8,%r9,__LC_MCK_OLD_PSW
652 tm __LC_MCCK_CODE,0x80 # system damage?
653 jo mcck_panic # yes -> rest of mcck code invalid
654 la %r14,__LC_CPU_TIMER_SAVE_AREA
655 mvc __LC_MCCK_ENTER_TIMER(8),0(%r14)
656 tm __LC_MCCK_CODE+5,0x02 # stored cpu timer value valid?
657 jo 3f
658 la %r14,__LC_SYNC_ENTER_TIMER
659 clc 0(8,%r14),__LC_ASYNC_ENTER_TIMER
660 jl 0f
661 la %r14,__LC_ASYNC_ENTER_TIMER
6620: clc 0(8,%r14),__LC_EXIT_TIMER
663 jl 1f
664 la %r14,__LC_EXIT_TIMER
6651: clc 0(8,%r14),__LC_LAST_UPDATE_TIMER
666 jl 2f
667 la %r14,__LC_LAST_UPDATE_TIMER
6682: spt 0(%r14)
669 mvc __LC_MCCK_ENTER_TIMER(8),0(%r14)
6703: tm __LC_MCCK_CODE+2,0x09 # mwp + ia of old psw valid?
671 jno mcck_panic # no -> skip cleanup critical
672 tm %r8,0x0001 # interrupting from user ?
673 jz mcck_skip
674 UPDATE_VTIME %r14,%r15,__LC_MCCK_ENTER_TIMER
675mcck_skip:
676 SWITCH_ASYNC __LC_GPREGS_SAVE_AREA+32,__LC_PANIC_STACK,PAGE_SHIFT
677 stm %r0,%r7,__PT_R0(%r11)
678 mvc __PT_R8(32,%r11),__LC_GPREGS_SAVE_AREA+32
679 stm %r8,%r9,__PT_PSW(%r11)
680 xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
681 l %r1,BASED(.Ldo_machine_check)
682 lr %r2,%r11 # pass pointer to pt_regs
683 basr %r14,%r1 # call s390_do_machine_check
684 tm __PT_PSW+1(%r11),0x01 # returning to user ?
685 jno mcck_return
686 l %r1,__LC_KERNEL_STACK # switch to kernel stack
687 mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
688 xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1)
689 la %r11,STACK_FRAME_OVERHEAD(%r15)
690 lr %r15,%r1
691 ssm __LC_PGM_NEW_PSW # turn dat on, keep irqs off
692 tm __TI_flags+3(%r12),_TIF_MCCK_PENDING
693 jno mcck_return
694 TRACE_IRQS_OFF
695 l %r1,BASED(.Lhandle_mcck)
696 basr %r14,%r1 # call s390_handle_mcck
697 TRACE_IRQS_ON
698mcck_return:
699 mvc __LC_RETURN_MCCK_PSW(8),__PT_PSW(%r11) # move return PSW
700 tm __LC_RETURN_MCCK_PSW+1,0x01 # returning to user ?
701 jno 0f
702 lm %r0,%r15,__PT_R0(%r11)
703 stpt __LC_EXIT_TIMER
704 lpsw __LC_RETURN_MCCK_PSW
7050: lm %r0,%r15,__PT_R0(%r11)
706 lpsw __LC_RETURN_MCCK_PSW
707
708mcck_panic:
709 l %r14,__LC_PANIC_STACK
710 slr %r14,%r15
711 sra %r14,PAGE_SHIFT
712 jz 0f
713 l %r15,__LC_PANIC_STACK
714 j mcck_skip
7150: ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
716 j mcck_skip
717
718#
719# PSW restart interrupt handler
720#
721ENTRY(restart_int_handler)
722 st %r15,__LC_SAVE_AREA_RESTART
723 l %r15,__LC_RESTART_STACK
724 ahi %r15,-__PT_SIZE # create pt_regs on stack
725 xc 0(__PT_SIZE,%r15),0(%r15)
726 stm %r0,%r14,__PT_R0(%r15)
727 mvc __PT_R15(4,%r15),__LC_SAVE_AREA_RESTART
728 mvc __PT_PSW(8,%r15),__LC_RST_OLD_PSW # store restart old psw
729 ahi %r15,-STACK_FRAME_OVERHEAD # create stack frame on stack
730 xc 0(STACK_FRAME_OVERHEAD,%r15),0(%r15)
731 l %r1,__LC_RESTART_FN # load fn, parm & source cpu
732 l %r2,__LC_RESTART_DATA
733 l %r3,__LC_RESTART_SOURCE
734 ltr %r3,%r3 # test source cpu address
735 jm 1f # negative -> skip source stop
7360: sigp %r4,%r3,SIGP_SENSE # sigp sense to source cpu
737 brc 10,0b # wait for status stored
7381: basr %r14,%r1 # call function
739 stap __SF_EMPTY(%r15) # store cpu address
740 lh %r3,__SF_EMPTY(%r15)
7412: sigp %r4,%r3,SIGP_STOP # sigp stop to current cpu
742 brc 2,2b
7433: j 3b
744
745 .section .kprobes.text, "ax"
746
747#ifdef CONFIG_CHECK_STACK
748/*
749 * The synchronous or the asynchronous stack overflowed. We are dead.
750 * No need to properly save the registers, we are going to panic anyway.
751 * Setup a pt_regs so that show_trace can provide a good call trace.
752 */
753stack_overflow:
754 l %r15,__LC_PANIC_STACK # change to panic stack
755 la %r11,STACK_FRAME_OVERHEAD(%r15)
756 stm %r0,%r7,__PT_R0(%r11)
757 stm %r8,%r9,__PT_PSW(%r11)
758 mvc __PT_R8(32,%r11),0(%r14)
759 l %r1,BASED(1f)
760 xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
761 lr %r2,%r11 # pass pointer to pt_regs
762 br %r1 # branch to kernel_stack_overflow
7631: .long kernel_stack_overflow
764#endif
765
766cleanup_table:
767 .long system_call + 0x80000000
768 .long sysc_do_svc + 0x80000000
769 .long sysc_tif + 0x80000000
770 .long sysc_restore + 0x80000000
771 .long sysc_done + 0x80000000
772 .long io_tif + 0x80000000
773 .long io_restore + 0x80000000
774 .long io_done + 0x80000000
775 .long psw_idle + 0x80000000
776 .long psw_idle_end + 0x80000000
777
778cleanup_critical:
779 cl %r9,BASED(cleanup_table) # system_call
780 jl 0f
781 cl %r9,BASED(cleanup_table+4) # sysc_do_svc
782 jl cleanup_system_call
783 cl %r9,BASED(cleanup_table+8) # sysc_tif
784 jl 0f
785 cl %r9,BASED(cleanup_table+12) # sysc_restore
786 jl cleanup_sysc_tif
787 cl %r9,BASED(cleanup_table+16) # sysc_done
788 jl cleanup_sysc_restore
789 cl %r9,BASED(cleanup_table+20) # io_tif
790 jl 0f
791 cl %r9,BASED(cleanup_table+24) # io_restore
792 jl cleanup_io_tif
793 cl %r9,BASED(cleanup_table+28) # io_done
794 jl cleanup_io_restore
795 cl %r9,BASED(cleanup_table+32) # psw_idle
796 jl 0f
797 cl %r9,BASED(cleanup_table+36) # psw_idle_end
798 jl cleanup_idle
7990: br %r14
800
801cleanup_system_call:
802 # check if stpt has been executed
803 cl %r9,BASED(cleanup_system_call_insn)
804 jh 0f
805 mvc __LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER
806 chi %r11,__LC_SAVE_AREA_ASYNC
807 je 0f
808 mvc __LC_SYNC_ENTER_TIMER(8),__LC_MCCK_ENTER_TIMER
8090: # check if stm has been executed
810 cl %r9,BASED(cleanup_system_call_insn+4)
811 jh 0f
812 mvc __LC_SAVE_AREA_SYNC(32),0(%r11)
8130: # set up saved registers r12, and r13
814 st %r12,16(%r11) # r12 thread-info pointer
815 st %r13,20(%r11) # r13 literal-pool pointer
816 # check if the user time calculation has been done
817 cl %r9,BASED(cleanup_system_call_insn+8)
818 jh 0f
819 l %r10,__LC_EXIT_TIMER
820 l %r15,__LC_EXIT_TIMER+4
821 SUB64 %r10,%r15,__LC_SYNC_ENTER_TIMER
822 ADD64 %r10,%r15,__LC_USER_TIMER
823 st %r10,__LC_USER_TIMER
824 st %r15,__LC_USER_TIMER+4
8250: # check if the system time calculation has been done
826 cl %r9,BASED(cleanup_system_call_insn+12)
827 jh 0f
828 l %r10,__LC_LAST_UPDATE_TIMER
829 l %r15,__LC_LAST_UPDATE_TIMER+4
830 SUB64 %r10,%r15,__LC_EXIT_TIMER
831 ADD64 %r10,%r15,__LC_SYSTEM_TIMER
832 st %r10,__LC_SYSTEM_TIMER
833 st %r15,__LC_SYSTEM_TIMER+4
8340: # update accounting time stamp
835 mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
836 # set up saved register 11
837 l %r15,__LC_KERNEL_STACK
838 la %r9,STACK_FRAME_OVERHEAD(%r15)
839 st %r9,12(%r11) # r11 pt_regs pointer
840 # fill pt_regs
841 mvc __PT_R8(32,%r9),__LC_SAVE_AREA_SYNC
842 stm %r0,%r7,__PT_R0(%r9)
843 mvc __PT_PSW(8,%r9),__LC_SVC_OLD_PSW
844 mvc __PT_INT_CODE(4,%r9),__LC_SVC_ILC
845 # setup saved register 15
846 st %r15,28(%r11) # r15 stack pointer
847 # set new psw address and exit
848 l %r9,BASED(cleanup_table+4) # sysc_do_svc + 0x80000000
849 br %r14
850cleanup_system_call_insn:
851 .long system_call + 0x80000000
852 .long sysc_stm + 0x80000000
853 .long sysc_vtime + 0x80000000 + 36
854 .long sysc_vtime + 0x80000000 + 76
855
856cleanup_sysc_tif:
857 l %r9,BASED(cleanup_table+8) # sysc_tif + 0x80000000
858 br %r14
859
860cleanup_sysc_restore:
861 cl %r9,BASED(cleanup_sysc_restore_insn)
862 jhe 0f
863 l %r9,12(%r11) # get saved pointer to pt_regs
864 mvc __LC_RETURN_PSW(8),__PT_PSW(%r9)
865 mvc 0(32,%r11),__PT_R8(%r9)
866 lm %r0,%r7,__PT_R0(%r9)
8670: lm %r8,%r9,__LC_RETURN_PSW
868 br %r14
869cleanup_sysc_restore_insn:
870 .long sysc_done - 4 + 0x80000000
871
872cleanup_io_tif:
873 l %r9,BASED(cleanup_table+20) # io_tif + 0x80000000
874 br %r14
875
876cleanup_io_restore:
877 cl %r9,BASED(cleanup_io_restore_insn)
878 jhe 0f
879 l %r9,12(%r11) # get saved r11 pointer to pt_regs
880 mvc __LC_RETURN_PSW(8),__PT_PSW(%r9)
881 mvc 0(32,%r11),__PT_R8(%r9)
882 lm %r0,%r7,__PT_R0(%r9)
8830: lm %r8,%r9,__LC_RETURN_PSW
884 br %r14
885cleanup_io_restore_insn:
886 .long io_done - 4 + 0x80000000
887
888cleanup_idle:
889 # copy interrupt clock & cpu timer
890 mvc __CLOCK_IDLE_EXIT(8,%r2),__LC_INT_CLOCK
891 mvc __TIMER_IDLE_EXIT(8,%r2),__LC_ASYNC_ENTER_TIMER
892 chi %r11,__LC_SAVE_AREA_ASYNC
893 je 0f
894 mvc __CLOCK_IDLE_EXIT(8,%r2),__LC_MCCK_CLOCK
895 mvc __TIMER_IDLE_EXIT(8,%r2),__LC_MCCK_ENTER_TIMER
8960: # check if stck has been executed
897 cl %r9,BASED(cleanup_idle_insn)
898 jhe 1f
899 mvc __CLOCK_IDLE_ENTER(8,%r2),__CLOCK_IDLE_EXIT(%r2)
900 mvc __TIMER_IDLE_ENTER(8,%r2),__TIMER_IDLE_EXIT(%r3)
9011: # account system time going idle
902 lm %r9,%r10,__LC_STEAL_TIMER
903 ADD64 %r9,%r10,__CLOCK_IDLE_ENTER(%r2)
904 SUB64 %r9,%r10,__LC_LAST_UPDATE_CLOCK
905 stm %r9,%r10,__LC_STEAL_TIMER
906 mvc __LC_LAST_UPDATE_CLOCK(8),__CLOCK_IDLE_EXIT(%r2)
907 lm %r9,%r10,__LC_SYSTEM_TIMER
908 ADD64 %r9,%r10,__LC_LAST_UPDATE_TIMER
909 SUB64 %r9,%r10,__TIMER_IDLE_ENTER(%r2)
910 stm %r9,%r10,__LC_SYSTEM_TIMER
911 mvc __LC_LAST_UPDATE_TIMER(8),__TIMER_IDLE_EXIT(%r2)
912 # prepare return psw
913 n %r8,BASED(cleanup_idle_wait) # clear irq & wait state bits
914 l %r9,24(%r11) # return from psw_idle
915 br %r14
916cleanup_idle_insn:
917 .long psw_idle_lpsw + 0x80000000
918cleanup_idle_wait:
919 .long 0xfcfdffff
920
921/*
922 * Integer constants
923 */
924 .align 4
925.Lnr_syscalls:
926 .long NR_syscalls
927.Lvtimer_max:
928 .quad 0x7fffffffffffffff
929
930/*
931 * Symbol constants
932 */
933.Ldo_machine_check: .long s390_do_machine_check
934.Lhandle_mcck: .long s390_handle_mcck
935.Ldo_IRQ: .long do_IRQ
936.Ldo_signal: .long do_signal
937.Ldo_notify_resume: .long do_notify_resume
938.Ldo_per_trap: .long do_per_trap
939.Ljump_table: .long pgm_check_table
940.Lschedule: .long schedule
941#ifdef CONFIG_PREEMPT
942.Lpreempt_irq: .long preempt_schedule_irq
943#endif
944.Ltrace_enter: .long do_syscall_trace_enter
945.Ltrace_exit: .long do_syscall_trace_exit
946.Lschedule_tail: .long schedule_tail
947.Lsysc_per: .long sysc_per + 0x80000000
948#ifdef CONFIG_TRACE_IRQFLAGS
949.Lhardirqs_on: .long trace_hardirqs_on_caller
950.Lhardirqs_off: .long trace_hardirqs_off_caller
951#endif
952#ifdef CONFIG_LOCKDEP
953.Llockdep_sys_exit: .long lockdep_sys_exit
954#endif
955.Lcritical_start: .long __critical_start + 0x80000000
956.Lcritical_length: .long __critical_end - __critical_start
957
958 .section .rodata, "a"
959#define SYSCALL(esa,esame,emu) .long esa
960 .globl sys_call_table
961sys_call_table:
962#include "syscalls.S"
963#undef SYSCALL