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1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * S390 low-level entry points.
4 *
5 * Copyright IBM Corp. 1999, 2012
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 */
10
11#include <linux/export.h>
12#include <linux/init.h>
13#include <linux/linkage.h>
14#include <asm/asm-extable.h>
15#include <asm/alternative.h>
16#include <asm/processor.h>
17#include <asm/cache.h>
18#include <asm/dwarf.h>
19#include <asm/errno.h>
20#include <asm/ptrace.h>
21#include <asm/thread_info.h>
22#include <asm/asm-offsets.h>
23#include <asm/unistd.h>
24#include <asm/page.h>
25#include <asm/sigp.h>
26#include <asm/irq.h>
27#include <asm/fpu-insn.h>
28#include <asm/setup.h>
29#include <asm/nmi.h>
30#include <asm/nospec-insn.h>
31#include <asm/lowcore.h>
32
33_LPP_OFFSET = __LC_LPP
34
35 .macro STBEAR address
36 ALTERNATIVE "nop", ".insn s,0xb2010000,\address", ALT_FACILITY(193)
37 .endm
38
39 .macro LBEAR address
40 ALTERNATIVE "nop", ".insn s,0xb2000000,\address", ALT_FACILITY(193)
41 .endm
42
43 .macro LPSWEY address, lpswe
44 ALTERNATIVE_2 "b \lpswe;nopr", \
45 ".insn siy,0xeb0000000071,\address,0", ALT_FACILITY(193), \
46 __stringify(.insn siy,0xeb0000000071,LOWCORE_ALT_ADDRESS+\address,0), \
47 ALT_LOWCORE
48 .endm
49
50 .macro MBEAR reg, lowcore
51 ALTERNATIVE "brcl 0,0", __stringify(mvc __PT_LAST_BREAK(8,\reg),__LC_LAST_BREAK(\lowcore)),\
52 ALT_FACILITY(193)
53 .endm
54
55 .macro CHECK_STACK savearea, lowcore
56#ifdef CONFIG_CHECK_STACK
57 tml %r15,THREAD_SIZE - CONFIG_STACK_GUARD
58 la %r14,\savearea(\lowcore)
59 jz stack_overflow
60#endif
61 .endm
62
63 .macro CHECK_VMAP_STACK savearea, lowcore, oklabel
64#ifdef CONFIG_VMAP_STACK
65 lgr %r14,%r15
66 nill %r14,0x10000 - THREAD_SIZE
67 oill %r14,STACK_INIT_OFFSET
68 clg %r14,__LC_KERNEL_STACK(\lowcore)
69 je \oklabel
70 clg %r14,__LC_ASYNC_STACK(\lowcore)
71 je \oklabel
72 clg %r14,__LC_MCCK_STACK(\lowcore)
73 je \oklabel
74 clg %r14,__LC_NODAT_STACK(\lowcore)
75 je \oklabel
76 clg %r14,__LC_RESTART_STACK(\lowcore)
77 je \oklabel
78 la %r14,\savearea(\lowcore)
79 j stack_overflow
80#else
81 j \oklabel
82#endif
83 .endm
84
85 /*
86 * The TSTMSK macro generates a test-under-mask instruction by
87 * calculating the memory offset for the specified mask value.
88 * Mask value can be any constant. The macro shifts the mask
89 * value to calculate the memory offset for the test-under-mask
90 * instruction.
91 */
92 .macro TSTMSK addr, mask, size=8, bytepos=0
93 .if (\bytepos < \size) && (\mask >> 8)
94 .if (\mask & 0xff)
95 .error "Mask exceeds byte boundary"
96 .endif
97 TSTMSK \addr, "(\mask >> 8)", \size, "(\bytepos + 1)"
98 .exitm
99 .endif
100 .ifeq \mask
101 .error "Mask must not be zero"
102 .endif
103 off = \size - \bytepos - 1
104 tm off+\addr, \mask
105 .endm
106
107 .macro BPOFF
108 ALTERNATIVE "nop", ".insn rrf,0xb2e80000,0,0,12,0", ALT_SPEC(82)
109 .endm
110
111 .macro BPON
112 ALTERNATIVE "nop", ".insn rrf,0xb2e80000,0,0,13,0", ALT_SPEC(82)
113 .endm
114
115 .macro BPENTER tif_ptr,tif_mask
116 ALTERNATIVE "TSTMSK \tif_ptr,\tif_mask; jz .+8; .insn rrf,0xb2e80000,0,0,13,0", \
117 "j .+12; nop; nop", ALT_SPEC(82)
118 .endm
119
120 .macro BPEXIT tif_ptr,tif_mask
121 TSTMSK \tif_ptr,\tif_mask
122 ALTERNATIVE "jz .+8; .insn rrf,0xb2e80000,0,0,12,0", \
123 "jnz .+8; .insn rrf,0xb2e80000,0,0,13,0", ALT_SPEC(82)
124 .endm
125
126#if IS_ENABLED(CONFIG_KVM)
127 .macro SIEEXIT sie_control,lowcore
128 lg %r9,\sie_control # get control block pointer
129 ni __SIE_PROG0C+3(%r9),0xfe # no longer in SIE
130 lctlg %c1,%c1,__LC_KERNEL_ASCE(\lowcore) # load primary asce
131 lg %r9,__LC_CURRENT(\lowcore)
132 mvi __TI_sie(%r9),0
133 larl %r9,sie_exit # skip forward to sie_exit
134 .endm
135#endif
136
137 .macro STACKLEAK_ERASE
138#ifdef CONFIG_GCC_PLUGIN_STACKLEAK
139 brasl %r14,stackleak_erase_on_task_stack
140#endif
141 .endm
142
143 GEN_BR_THUNK %r14
144
145 .section .kprobes.text, "ax"
146.Ldummy:
147 /*
148 * The following nop exists only in order to avoid that the next
149 * symbol starts at the beginning of the kprobes text section.
150 * In that case there would be several symbols at the same address.
151 * E.g. objdump would take an arbitrary symbol when disassembling
152 * the code.
153 * With the added nop in between this cannot happen.
154 */
155 nop 0
156
157/*
158 * Scheduler resume function, called by __switch_to
159 * gpr2 = (task_struct *)prev
160 * gpr3 = (task_struct *)next
161 * Returns:
162 * gpr2 = prev
163 */
164SYM_FUNC_START(__switch_to_asm)
165 stmg %r6,%r15,__SF_GPRS(%r15) # store gprs of prev task
166 lghi %r4,__TASK_stack
167 lghi %r1,__TASK_thread
168 llill %r5,STACK_INIT_OFFSET
169 stg %r15,__THREAD_ksp(%r1,%r2) # store kernel stack of prev
170 lg %r15,0(%r4,%r3) # start of kernel stack of next
171 agr %r15,%r5 # end of kernel stack of next
172 GET_LC %r13
173 stg %r3,__LC_CURRENT(%r13) # store task struct of next
174 stg %r15,__LC_KERNEL_STACK(%r13) # store end of kernel stack
175 lg %r15,__THREAD_ksp(%r1,%r3) # load kernel stack of next
176 aghi %r3,__TASK_pid
177 mvc __LC_CURRENT_PID(4,%r13),0(%r3) # store pid of next
178 ALTERNATIVE "nop", "lpp _LPP_OFFSET(%r13)", ALT_FACILITY(40)
179 lmg %r6,%r15,__SF_GPRS(%r15) # load gprs of next task
180 BR_EX %r14
181SYM_FUNC_END(__switch_to_asm)
182
183#if IS_ENABLED(CONFIG_KVM)
184/*
185 * __sie64a calling convention:
186 * %r2 pointer to sie control block phys
187 * %r3 pointer to sie control block virt
188 * %r4 guest register save area
189 * %r5 guest asce
190 */
191SYM_FUNC_START(__sie64a)
192 stmg %r6,%r14,__SF_GPRS(%r15) # save kernel registers
193 GET_LC %r13
194 lg %r14,__LC_CURRENT(%r13)
195 stg %r2,__SF_SIE_CONTROL_PHYS(%r15) # save sie block physical..
196 stg %r3,__SF_SIE_CONTROL(%r15) # ...and virtual addresses
197 stg %r4,__SF_SIE_SAVEAREA(%r15) # save guest register save area
198 stg %r5,__SF_SIE_GUEST_ASCE(%r15) # save guest asce
199 xc __SF_SIE_REASON(8,%r15),__SF_SIE_REASON(%r15) # reason code = 0
200 mvc __SF_SIE_FLAGS(8,%r15),__TI_flags(%r14) # copy thread flags
201 lmg %r0,%r13,0(%r4) # load guest gprs 0-13
202 mvi __TI_sie(%r14),1
203 lctlg %c1,%c1,__SF_SIE_GUEST_ASCE(%r15) # load primary asce
204 lg %r14,__SF_SIE_CONTROL(%r15) # get control block pointer
205 oi __SIE_PROG0C+3(%r14),1 # we are going into SIE now
206 tm __SIE_PROG20+3(%r14),3 # last exit...
207 jnz .Lsie_skip
208 lg %r14,__SF_SIE_CONTROL_PHYS(%r15) # get sie block phys addr
209 BPEXIT __SF_SIE_FLAGS(%r15),_TIF_ISOLATE_BP_GUEST
210.Lsie_entry:
211 sie 0(%r14)
212# Let the next instruction be NOP to avoid triggering a machine check
213# and handling it in a guest as result of the instruction execution.
214 nopr 7
215.Lsie_leave:
216 BPOFF
217 BPENTER __SF_SIE_FLAGS(%r15),_TIF_ISOLATE_BP_GUEST
218.Lsie_skip:
219 lg %r14,__SF_SIE_CONTROL(%r15) # get control block pointer
220 ni __SIE_PROG0C+3(%r14),0xfe # no longer in SIE
221 GET_LC %r14
222 lctlg %c1,%c1,__LC_KERNEL_ASCE(%r14) # load primary asce
223 lg %r14,__LC_CURRENT(%r14)
224 mvi __TI_sie(%r14),0
225SYM_INNER_LABEL(sie_exit, SYM_L_GLOBAL)
226 lg %r14,__SF_SIE_SAVEAREA(%r15) # load guest register save area
227 stmg %r0,%r13,0(%r14) # save guest gprs 0-13
228 xgr %r0,%r0 # clear guest registers to
229 xgr %r1,%r1 # prevent speculative use
230 xgr %r3,%r3
231 xgr %r4,%r4
232 xgr %r5,%r5
233 lmg %r6,%r14,__SF_GPRS(%r15) # restore kernel registers
234 lg %r2,__SF_SIE_REASON(%r15) # return exit reason code
235 BR_EX %r14
236SYM_FUNC_END(__sie64a)
237EXPORT_SYMBOL(__sie64a)
238EXPORT_SYMBOL(sie_exit)
239#endif
240
241/*
242 * SVC interrupt handler routine. System calls are synchronous events and
243 * are entered with interrupts disabled.
244 */
245
246SYM_CODE_START(system_call)
247 STMG_LC %r8,%r15,__LC_SAVE_AREA
248 GET_LC %r13
249 stpt __LC_SYS_ENTER_TIMER(%r13)
250 BPOFF
251 lghi %r14,0
252.Lsysc_per:
253 STBEAR __LC_LAST_BREAK(%r13)
254 lctlg %c1,%c1,__LC_KERNEL_ASCE(%r13)
255 lg %r15,__LC_KERNEL_STACK(%r13)
256 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
257 stmg %r0,%r7,STACK_FRAME_OVERHEAD+__PT_R0(%r15)
258 # clear user controlled register to prevent speculative use
259 xgr %r0,%r0
260 xgr %r1,%r1
261 xgr %r4,%r4
262 xgr %r5,%r5
263 xgr %r6,%r6
264 xgr %r7,%r7
265 xgr %r8,%r8
266 xgr %r9,%r9
267 xgr %r10,%r10
268 xgr %r11,%r11
269 la %r2,STACK_FRAME_OVERHEAD(%r15) # pointer to pt_regs
270 mvc __PT_R8(64,%r2),__LC_SAVE_AREA(%r13)
271 MBEAR %r2,%r13
272 lgr %r3,%r14
273 brasl %r14,__do_syscall
274 STACKLEAK_ERASE
275 lctlg %c1,%c1,__LC_USER_ASCE(%r13)
276 mvc __LC_RETURN_PSW(16,%r13),STACK_FRAME_OVERHEAD+__PT_PSW(%r15)
277 BPON
278 LBEAR STACK_FRAME_OVERHEAD+__PT_LAST_BREAK(%r15)
279 stpt __LC_EXIT_TIMER(%r13)
280 lmg %r0,%r15,STACK_FRAME_OVERHEAD+__PT_R0(%r15)
281 LPSWEY __LC_RETURN_PSW,__LC_RETURN_LPSWE
282SYM_CODE_END(system_call)
283
284#
285# a new process exits the kernel with ret_from_fork
286#
287SYM_CODE_START(ret_from_fork)
288 lgr %r3,%r11
289 brasl %r14,__ret_from_fork
290 STACKLEAK_ERASE
291 GET_LC %r13
292 lctlg %c1,%c1,__LC_USER_ASCE(%r13)
293 mvc __LC_RETURN_PSW(16,%r13),STACK_FRAME_OVERHEAD+__PT_PSW(%r15)
294 BPON
295 LBEAR STACK_FRAME_OVERHEAD+__PT_LAST_BREAK(%r15)
296 stpt __LC_EXIT_TIMER(%r13)
297 lmg %r0,%r15,STACK_FRAME_OVERHEAD+__PT_R0(%r15)
298 LPSWEY __LC_RETURN_PSW,__LC_RETURN_LPSWE
299SYM_CODE_END(ret_from_fork)
300
301/*
302 * Program check handler routine
303 */
304
305SYM_CODE_START(pgm_check_handler)
306 STMG_LC %r8,%r15,__LC_SAVE_AREA
307 GET_LC %r13
308 stpt __LC_SYS_ENTER_TIMER(%r13)
309 BPOFF
310 lmg %r8,%r9,__LC_PGM_OLD_PSW(%r13)
311 xgr %r10,%r10
312 tmhh %r8,0x0001 # coming from user space?
313 jno .Lpgm_skip_asce
314 lctlg %c1,%c1,__LC_KERNEL_ASCE(%r13)
315 j 3f # -> fault in user space
316.Lpgm_skip_asce:
317#if IS_ENABLED(CONFIG_KVM)
318 lg %r11,__LC_CURRENT(%r13)
319 tm __TI_sie(%r11),0xff
320 jz 1f
321 BPENTER __SF_SIE_FLAGS(%r15),_TIF_ISOLATE_BP_GUEST
322 SIEEXIT __SF_SIE_CONTROL(%r15),%r13
323 lghi %r10,_PIF_GUEST_FAULT
324#endif
3251: tmhh %r8,0x4000 # PER bit set in old PSW ?
326 jnz 2f # -> enabled, can't be a double fault
327 tm __LC_PGM_ILC+3(%r13),0x80 # check for per exception
328 jnz .Lpgm_svcper # -> single stepped svc
3292: CHECK_STACK __LC_SAVE_AREA,%r13
330 aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
331 # CHECK_VMAP_STACK branches to stack_overflow or 4f
332 CHECK_VMAP_STACK __LC_SAVE_AREA,%r13,4f
3333: lg %r15,__LC_KERNEL_STACK(%r13)
3344: la %r11,STACK_FRAME_OVERHEAD(%r15)
335 stg %r10,__PT_FLAGS(%r11)
336 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
337 stmg %r0,%r7,__PT_R0(%r11)
338 mvc __PT_R8(64,%r11),__LC_SAVE_AREA(%r13)
339 mvc __PT_LAST_BREAK(8,%r11),__LC_PGM_LAST_BREAK(%r13)
340 stmg %r8,%r9,__PT_PSW(%r11)
341 # clear user controlled registers to prevent speculative use
342 xgr %r0,%r0
343 xgr %r1,%r1
344 xgr %r3,%r3
345 xgr %r4,%r4
346 xgr %r5,%r5
347 xgr %r6,%r6
348 xgr %r7,%r7
349 xgr %r12,%r12
350 lgr %r2,%r11
351 brasl %r14,__do_pgm_check
352 tmhh %r8,0x0001 # returning to user space?
353 jno .Lpgm_exit_kernel
354 STACKLEAK_ERASE
355 lctlg %c1,%c1,__LC_USER_ASCE(%r13)
356 BPON
357 stpt __LC_EXIT_TIMER(%r13)
358.Lpgm_exit_kernel:
359 mvc __LC_RETURN_PSW(16,%r13),STACK_FRAME_OVERHEAD+__PT_PSW(%r15)
360 LBEAR STACK_FRAME_OVERHEAD+__PT_LAST_BREAK(%r15)
361 lmg %r0,%r15,STACK_FRAME_OVERHEAD+__PT_R0(%r15)
362 LPSWEY __LC_RETURN_PSW,__LC_RETURN_LPSWE
363
364#
365# single stepped system call
366#
367.Lpgm_svcper:
368 mvc __LC_RETURN_PSW(8,%r13),__LC_SVC_NEW_PSW(%r13)
369 larl %r14,.Lsysc_per
370 stg %r14,__LC_RETURN_PSW+8(%r13)
371 lghi %r14,1
372 LBEAR __LC_PGM_LAST_BREAK(%r13)
373 LPSWEY __LC_RETURN_PSW,__LC_RETURN_LPSWE # branch to .Lsysc_per
374SYM_CODE_END(pgm_check_handler)
375
376/*
377 * Interrupt handler macro used for external and IO interrupts.
378 */
379.macro INT_HANDLER name,lc_old_psw,handler
380SYM_CODE_START(\name)
381 STMG_LC %r8,%r15,__LC_SAVE_AREA
382 GET_LC %r13
383 stckf __LC_INT_CLOCK(%r13)
384 stpt __LC_SYS_ENTER_TIMER(%r13)
385 STBEAR __LC_LAST_BREAK(%r13)
386 BPOFF
387 lmg %r8,%r9,\lc_old_psw(%r13)
388 tmhh %r8,0x0001 # interrupting from user ?
389 jnz 1f
390#if IS_ENABLED(CONFIG_KVM)
391 lg %r10,__LC_CURRENT(%r13)
392 tm __TI_sie(%r10),0xff
393 jz 0f
394 BPENTER __SF_SIE_FLAGS(%r15),_TIF_ISOLATE_BP_GUEST
395 SIEEXIT __SF_SIE_CONTROL(%r15),%r13
396#endif
3970: CHECK_STACK __LC_SAVE_AREA,%r13
398 aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
399 j 2f
4001: lctlg %c1,%c1,__LC_KERNEL_ASCE(%r13)
401 lg %r15,__LC_KERNEL_STACK(%r13)
4022: xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
403 la %r11,STACK_FRAME_OVERHEAD(%r15)
404 stmg %r0,%r7,__PT_R0(%r11)
405 # clear user controlled registers to prevent speculative use
406 xgr %r0,%r0
407 xgr %r1,%r1
408 xgr %r3,%r3
409 xgr %r4,%r4
410 xgr %r5,%r5
411 xgr %r6,%r6
412 xgr %r7,%r7
413 xgr %r10,%r10
414 xc __PT_FLAGS(8,%r11),__PT_FLAGS(%r11)
415 mvc __PT_R8(64,%r11),__LC_SAVE_AREA(%r13)
416 MBEAR %r11,%r13
417 stmg %r8,%r9,__PT_PSW(%r11)
418 lgr %r2,%r11 # pass pointer to pt_regs
419 brasl %r14,\handler
420 mvc __LC_RETURN_PSW(16,%r13),__PT_PSW(%r11)
421 tmhh %r8,0x0001 # returning to user ?
422 jno 2f
423 STACKLEAK_ERASE
424 lctlg %c1,%c1,__LC_USER_ASCE(%r13)
425 BPON
426 stpt __LC_EXIT_TIMER(%r13)
4272: LBEAR __PT_LAST_BREAK(%r11)
428 lmg %r0,%r15,__PT_R0(%r11)
429 LPSWEY __LC_RETURN_PSW,__LC_RETURN_LPSWE
430SYM_CODE_END(\name)
431.endm
432
433 .section .irqentry.text, "ax"
434
435INT_HANDLER ext_int_handler,__LC_EXT_OLD_PSW,do_ext_irq
436INT_HANDLER io_int_handler,__LC_IO_OLD_PSW,do_io_irq
437
438 .section .kprobes.text, "ax"
439
440/*
441 * Machine check handler routines
442 */
443SYM_CODE_START(mcck_int_handler)
444 BPOFF
445 GET_LC %r13
446 lmg %r8,%r9,__LC_MCK_OLD_PSW(%r13)
447 TSTMSK __LC_MCCK_CODE(%r13),MCCK_CODE_SYSTEM_DAMAGE
448 jo .Lmcck_panic # yes -> rest of mcck code invalid
449 TSTMSK __LC_MCCK_CODE(%r13),MCCK_CODE_CR_VALID
450 jno .Lmcck_panic # control registers invalid -> panic
451 ptlb
452 lay %r14,__LC_CPU_TIMER_SAVE_AREA(%r13)
453 mvc __LC_MCCK_ENTER_TIMER(8,%r13),0(%r14)
454 TSTMSK __LC_MCCK_CODE(%r13),MCCK_CODE_CPU_TIMER_VALID
455 jo 3f
456 la %r14,__LC_SYS_ENTER_TIMER(%r13)
457 clc 0(8,%r14),__LC_EXIT_TIMER(%r13)
458 jl 1f
459 la %r14,__LC_EXIT_TIMER(%r13)
4601: clc 0(8,%r14),__LC_LAST_UPDATE_TIMER(%r13)
461 jl 2f
462 la %r14,__LC_LAST_UPDATE_TIMER(%r13)
4632: spt 0(%r14)
464 mvc __LC_MCCK_ENTER_TIMER(8,%r13),0(%r14)
4653: TSTMSK __LC_MCCK_CODE(%r13),MCCK_CODE_PSW_MWP_VALID
466 jno .Lmcck_panic
467 tmhh %r8,0x0001 # interrupting from user ?
468 jnz .Lmcck_user
469 TSTMSK __LC_MCCK_CODE(%r13),MCCK_CODE_PSW_IA_VALID
470 jno .Lmcck_panic
471#if IS_ENABLED(CONFIG_KVM)
472 lg %r10,__LC_CURRENT(%r13)
473 tm __TI_sie(%r10),0xff
474 jz .Lmcck_user
475 # Need to compare the address instead of __TI_SIE flag.
476 # Otherwise there would be a race between setting the flag
477 # and entering SIE (or leaving and clearing the flag). This
478 # would cause machine checks targeted at the guest to be
479 # handled by the host.
480 larl %r14,.Lsie_entry
481 clgrjl %r9,%r14, 4f
482 larl %r14,.Lsie_leave
483 clgrjhe %r9,%r14, 4f
484 lg %r10,__LC_PCPU
485 oi __PCPU_FLAGS+7(%r10), _CIF_MCCK_GUEST
4864: BPENTER __SF_SIE_FLAGS(%r15),_TIF_ISOLATE_BP_GUEST
487 SIEEXIT __SF_SIE_CONTROL(%r15),%r13
488#endif
489.Lmcck_user:
490 lg %r15,__LC_MCCK_STACK(%r13)
491 la %r11,STACK_FRAME_OVERHEAD(%r15)
492 stctg %c1,%c1,__PT_CR1(%r11)
493 lctlg %c1,%c1,__LC_KERNEL_ASCE(%r13)
494 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
495 lay %r14,__LC_GPREGS_SAVE_AREA(%r13)
496 mvc __PT_R0(128,%r11),0(%r14)
497 # clear user controlled registers to prevent speculative use
498 xgr %r0,%r0
499 xgr %r1,%r1
500 xgr %r3,%r3
501 xgr %r4,%r4
502 xgr %r5,%r5
503 xgr %r6,%r6
504 xgr %r7,%r7
505 xgr %r10,%r10
506 stmg %r8,%r9,__PT_PSW(%r11)
507 xc __PT_FLAGS(8,%r11),__PT_FLAGS(%r11)
508 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
509 lgr %r2,%r11 # pass pointer to pt_regs
510 brasl %r14,s390_do_machine_check
511 lctlg %c1,%c1,__PT_CR1(%r11)
512 lmg %r0,%r10,__PT_R0(%r11)
513 mvc __LC_RETURN_MCCK_PSW(16,%r13),__PT_PSW(%r11) # move return PSW
514 tm __LC_RETURN_MCCK_PSW+1(%r13),0x01 # returning to user ?
515 jno 0f
516 BPON
517 stpt __LC_EXIT_TIMER(%r13)
5180: ALTERNATIVE "brcl 0,0", __stringify(lay %r12,__LC_LAST_BREAK_SAVE_AREA(%r13)),\
519 ALT_FACILITY(193)
520 LBEAR 0(%r12)
521 lmg %r11,%r15,__PT_R11(%r11)
522 LPSWEY __LC_RETURN_MCCK_PSW,__LC_RETURN_MCCK_LPSWE
523
524.Lmcck_panic:
525 /*
526 * Iterate over all possible CPU addresses in the range 0..0xffff
527 * and stop each CPU using signal processor. Use compare and swap
528 * to allow just one CPU-stopper and prevent concurrent CPUs from
529 * stopping each other while leaving the others running.
530 */
531 lhi %r5,0
532 lhi %r6,1
533 larl %r7,stop_lock
534 cs %r5,%r6,0(%r7) # single CPU-stopper only
535 jnz 4f
536 larl %r7,this_cpu
537 stap 0(%r7) # this CPU address
538 lh %r4,0(%r7)
539 nilh %r4,0
540 lhi %r0,1
541 sll %r0,16 # CPU counter
542 lhi %r3,0 # next CPU address
5430: cr %r3,%r4
544 je 2f
5451: sigp %r1,%r3,SIGP_STOP # stop next CPU
546 brc SIGP_CC_BUSY,1b
5472: ahi %r3,1
548 brct %r0,0b
5493: sigp %r1,%r4,SIGP_STOP # stop this CPU
550 brc SIGP_CC_BUSY,3b
5514: j 4b
552SYM_CODE_END(mcck_int_handler)
553
554SYM_CODE_START(restart_int_handler)
555 ALTERNATIVE "nop", "lpp _LPP_OFFSET", ALT_FACILITY(40)
556 stg %r15,__LC_SAVE_AREA_RESTART
557 TSTMSK __LC_RESTART_FLAGS,RESTART_FLAG_CTLREGS,4
558 jz 0f
559 lctlg %c0,%c15,__LC_CREGS_SAVE_AREA
5600: larl %r15,daton_psw
561 lpswe 0(%r15) # turn dat on, keep irqs off
562.Ldaton:
563 GET_LC %r15
564 lg %r15,__LC_RESTART_STACK(%r15)
565 xc STACK_FRAME_OVERHEAD(__PT_SIZE,%r15),STACK_FRAME_OVERHEAD(%r15)
566 stmg %r0,%r14,STACK_FRAME_OVERHEAD+__PT_R0(%r15)
567 GET_LC %r13
568 mvc STACK_FRAME_OVERHEAD+__PT_R15(8,%r15),__LC_SAVE_AREA_RESTART(%r13)
569 mvc STACK_FRAME_OVERHEAD+__PT_PSW(16,%r15),__LC_RST_OLD_PSW(%r13)
570 xc 0(STACK_FRAME_OVERHEAD,%r15),0(%r15)
571 lg %r1,__LC_RESTART_FN(%r13) # load fn, parm & source cpu
572 lg %r2,__LC_RESTART_DATA(%r13)
573 lgf %r3,__LC_RESTART_SOURCE(%r13)
574 ltgr %r3,%r3 # test source cpu address
575 jm 1f # negative -> skip source stop
5760: sigp %r4,%r3,SIGP_SENSE # sigp sense to source cpu
577 brc 10,0b # wait for status stored
5781: basr %r14,%r1 # call function
579 stap __SF_EMPTY(%r15) # store cpu address
580 llgh %r3,__SF_EMPTY(%r15)
5812: sigp %r4,%r3,SIGP_STOP # sigp stop to current cpu
582 brc 2,2b
5833: j 3b
584SYM_CODE_END(restart_int_handler)
585
586 __INIT
587SYM_CODE_START(early_pgm_check_handler)
588 STMG_LC %r8,%r15,__LC_SAVE_AREA
589 GET_LC %r13
590 aghi %r15,-(STACK_FRAME_OVERHEAD+__PT_SIZE)
591 la %r11,STACK_FRAME_OVERHEAD(%r15)
592 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
593 stmg %r0,%r7,__PT_R0(%r11)
594 mvc __PT_PSW(16,%r11),__LC_PGM_OLD_PSW(%r13)
595 mvc __PT_R8(64,%r11),__LC_SAVE_AREA(%r13)
596 lgr %r2,%r11
597 brasl %r14,__do_early_pgm_check
598 mvc __LC_RETURN_PSW(16,%r13),STACK_FRAME_OVERHEAD+__PT_PSW(%r15)
599 lmg %r0,%r15,STACK_FRAME_OVERHEAD+__PT_R0(%r15)
600 LPSWEY __LC_RETURN_PSW,__LC_RETURN_LPSWE
601SYM_CODE_END(early_pgm_check_handler)
602 __FINIT
603
604 .section .kprobes.text, "ax"
605
606#if defined(CONFIG_CHECK_STACK) || defined(CONFIG_VMAP_STACK)
607/*
608 * The synchronous or the asynchronous stack overflowed. We are dead.
609 * No need to properly save the registers, we are going to panic anyway.
610 * Setup a pt_regs so that show_trace can provide a good call trace.
611 */
612SYM_CODE_START(stack_overflow)
613 GET_LC %r15
614 lg %r15,__LC_NODAT_STACK(%r15) # change to panic stack
615 la %r11,STACK_FRAME_OVERHEAD(%r15)
616 stmg %r0,%r7,__PT_R0(%r11)
617 stmg %r8,%r9,__PT_PSW(%r11)
618 mvc __PT_R8(64,%r11),0(%r14)
619 stg %r10,__PT_ORIG_GPR2(%r11) # store last break to orig_gpr2
620 xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
621 lgr %r2,%r11 # pass pointer to pt_regs
622 jg kernel_stack_overflow
623SYM_CODE_END(stack_overflow)
624#endif
625
626 .section .data, "aw"
627 .balign 4
628SYM_DATA_LOCAL(stop_lock, .long 0)
629SYM_DATA_LOCAL(this_cpu, .short 0)
630 .balign 8
631SYM_DATA_START_LOCAL(daton_psw)
632 .quad PSW_KERNEL_BITS
633 .quad .Ldaton
634SYM_DATA_END(daton_psw)
635
636 .section .rodata, "a"
637 .balign 8
638#define SYSCALL(esame,emu) .quad __s390x_ ## esame
639SYM_DATA_START(sys_call_table)
640#include "asm/syscall_table.h"
641SYM_DATA_END(sys_call_table)
642#undef SYSCALL
643
644#ifdef CONFIG_COMPAT
645
646#define SYSCALL(esame,emu) .quad __s390_ ## emu
647SYM_DATA_START(sys_call_table_emu)
648#include "asm/syscall_table.h"
649SYM_DATA_END(sys_call_table_emu)
650#undef SYSCALL
651#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