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 22__PT_R0 = __PT_GPRS 23__PT_R1 = __PT_GPRS + 4 24__PT_R2 = __PT_GPRS + 8 25__PT_R3 = __PT_GPRS + 12 26__PT_R4 = __PT_GPRS + 16 27__PT_R5 = __PT_GPRS + 20 28__PT_R6 = __PT_GPRS + 24 29__PT_R7 = __PT_GPRS + 28 30__PT_R8 = __PT_GPRS + 32 31__PT_R9 = __PT_GPRS + 36 32__PT_R10 = __PT_GPRS + 40 33__PT_R11 = __PT_GPRS + 44 34__PT_R12 = __PT_GPRS + 48 35__PT_R13 = __PT_GPRS + 524 36__PT_R14 = __PT_GPRS + 56 37__PT_R15 = __PT_GPRS + 60 38 39_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \ 40 _TIF_MCCK_PENDING | _TIF_PER_TRAP ) 41_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \ 42 _TIF_MCCK_PENDING) 43_TIF_TRACE = (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | \ 44 _TIF_SYSCALL_TRACEPOINT) 45 46STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER 47STACK_SIZE = 1 << STACK_SHIFT 48 49#define BASED(name) name-system_call(%r13) 50 51 .macro TRACE_IRQS_ON 52#ifdef CONFIG_TRACE_IRQFLAGS 53 basr %r2,%r0 54 l %r1,BASED(.Lhardirqs_on) 55 basr %r14,%r1 # call trace_hardirqs_on_caller 56#endif 57 .endm 58 59 .macro TRACE_IRQS_OFF 60#ifdef CONFIG_TRACE_IRQFLAGS 61 basr %r2,%r0 62 l %r1,BASED(.Lhardirqs_off) 63 basr %r14,%r1 # call trace_hardirqs_off_caller 64#endif 65 .endm 66 67 .macro LOCKDEP_SYS_EXIT 68#ifdef CONFIG_LOCKDEP 69 tm __PT_PSW+1(%r11),0x01 # returning to user ? 70 jz .+10 71 l %r1,BASED(.Llockdep_sys_exit) 72 basr %r14,%r1 # call lockdep_sys_exit 73#endif 74 .endm 75 76 .macro CHECK_STACK stacksize,savearea 77#ifdef CONFIG_CHECK_STACK 78 tml %r15,\stacksize - CONFIG_STACK_GUARD 79 la %r14,\savearea 80 jz stack_overflow 81#endif 82 .endm 83 84 .macro SWITCH_ASYNC savearea,stack,shift 85 tmh %r8,0x0001 # interrupting from user ? 86 jnz 1f 87 lr %r14,%r9 88 sl %r14,BASED(.Lcritical_start) 89 cl %r14,BASED(.Lcritical_length) 90 jhe 0f 91 la %r11,\savearea # inside critical section, do cleanup 92 bras %r14,cleanup_critical 93 tmh %r8,0x0001 # retest problem state after cleanup 94 jnz 1f 950: l %r14,\stack # are we already on the target stack? 96 slr %r14,%r15 97 sra %r14,\shift 98 jnz 1f 99 CHECK_STACK 1<<\shift,\savearea 100 j 2f 1011: l %r15,\stack # load target stack 1022: ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) 103 la %r11,STACK_FRAME_OVERHEAD(%r15) 104 .endm 105 106 .macro ADD64 high,low,timer 107 al \high,\timer 108 al \low,4+\timer 109 brc 12,.+8 110 ahi \high,1 111 .endm 112 113 .macro SUB64 high,low,timer 114 sl \high,\timer 115 sl \low,4+\timer 116 brc 3,.+8 117 ahi \high,-1 118 .endm 119 120 .macro UPDATE_VTIME high,low,enter_timer 121 lm \high,\low,__LC_EXIT_TIMER 122 SUB64 \high,\low,\enter_timer 123 ADD64 \high,\low,__LC_USER_TIMER 124 stm \high,\low,__LC_USER_TIMER 125 lm \high,\low,__LC_LAST_UPDATE_TIMER 126 SUB64 \high,\low,__LC_EXIT_TIMER 127 ADD64 \high,\low,__LC_SYSTEM_TIMER 128 stm \high,\low,__LC_SYSTEM_TIMER 129 mvc __LC_LAST_UPDATE_TIMER(8),\enter_timer 130 .endm 131 132 .macro REENABLE_IRQS 133 st %r8,__LC_RETURN_PSW 134 ni __LC_RETURN_PSW,0xbf 135 ssm __LC_RETURN_PSW 136 .endm 137 138 .section .kprobes.text, "ax" 139 140/* 141 * Scheduler resume function, called by switch_to 142 * gpr2 = (task_struct *) prev 143 * gpr3 = (task_struct *) next 144 * Returns: 145 * gpr2 = prev 146 */ 147ENTRY(__switch_to) 148 stm %r6,%r15,__SF_GPRS(%r15) # store gprs of prev task 149 st %r15,__THREAD_ksp(%r2) # store kernel stack of prev 150 l %r4,__THREAD_info(%r2) # get thread_info of prev 151 l %r5,__THREAD_info(%r3) # get thread_info of next 152 lr %r15,%r5 153 ahi %r15,STACK_SIZE # end of kernel stack of next 154 st %r3,__LC_CURRENT # store task struct of next 155 st %r5,__LC_THREAD_INFO # store thread info of next 156 st %r15,__LC_KERNEL_STACK # store end of kernel stack 157 lctl %c4,%c4,__TASK_pid(%r3) # load pid to control reg. 4 158 mvc __LC_CURRENT_PID(4,%r0),__TASK_pid(%r3) # store pid of next 159 l %r15,__THREAD_ksp(%r3) # load kernel stack of next 160 tm __TI_flags+3(%r4),_TIF_MCCK_PENDING # machine check pending? 161 jz 0f 162 ni __TI_flags+3(%r4),255-_TIF_MCCK_PENDING # clear flag in prev 163 oi __TI_flags+3(%r5),_TIF_MCCK_PENDING # set it in next 1640: lm %r6,%r15,__SF_GPRS(%r15) # load gprs of next task 165 br %r14 166 167__critical_start: 168/* 169 * SVC interrupt handler routine. System calls are synchronous events and 170 * are executed with interrupts enabled. 171 */ 172 173ENTRY(system_call) 174 stpt __LC_SYNC_ENTER_TIMER 175sysc_stm: 176 stm %r8,%r15,__LC_SAVE_AREA_SYNC 177 l %r12,__LC_THREAD_INFO 178 l %r13,__LC_SVC_NEW_PSW+4 179sysc_per: 180 l %r15,__LC_KERNEL_STACK 181 ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) 182 la %r11,STACK_FRAME_OVERHEAD(%r15) # pointer to pt_regs 183sysc_vtime: 184 UPDATE_VTIME %r8,%r9,__LC_SYNC_ENTER_TIMER 185 stm %r0,%r7,__PT_R0(%r11) 186 mvc __PT_R8(32,%r11),__LC_SAVE_AREA_SYNC 187 mvc __PT_PSW(8,%r11),__LC_SVC_OLD_PSW 188 mvc __PT_INT_CODE(4,%r11),__LC_SVC_ILC 189sysc_do_svc: 190 oi __TI_flags+3(%r12),_TIF_SYSCALL 191 lh %r8,__PT_INT_CODE+2(%r11) 192 sla %r8,2 # shift and test for svc0 193 jnz sysc_nr_ok 194 # svc 0: system call number in %r1 195 cl %r1,BASED(.Lnr_syscalls) 196 jnl sysc_nr_ok 197 sth %r1,__PT_INT_CODE+2(%r11) 198 lr %r8,%r1 199 sla %r8,2 200sysc_nr_ok: 201 l %r10,BASED(.Lsys_call_table) # 31 bit system call table 202 xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) 203 st %r2,__PT_ORIG_GPR2(%r11) 204 st %r7,STACK_FRAME_OVERHEAD(%r15) 205 l %r9,0(%r8,%r10) # get system call addr. 206 tm __TI_flags+2(%r12),_TIF_TRACE >> 8 207 jnz sysc_tracesys 208 basr %r14,%r9 # call sys_xxxx 209 st %r2,__PT_R2(%r11) # store return value 210 211sysc_return: 212 LOCKDEP_SYS_EXIT 213sysc_tif: 214 tm __PT_PSW+1(%r11),0x01 # returning to user ? 215 jno sysc_restore 216 tm __TI_flags+3(%r12),_TIF_WORK_SVC 217 jnz sysc_work # check for work 218 ni __TI_flags+3(%r12),255-_TIF_SYSCALL 219sysc_restore: 220 mvc __LC_RETURN_PSW(8),__PT_PSW(%r11) 221 stpt __LC_EXIT_TIMER 222 lm %r0,%r15,__PT_R0(%r11) 223 lpsw __LC_RETURN_PSW 224sysc_done: 225 226# 227# One of the work bits is on. Find out which one. 228# 229sysc_work: 230 tm __TI_flags+3(%r12),_TIF_MCCK_PENDING 231 jo sysc_mcck_pending 232 tm __TI_flags+3(%r12),_TIF_NEED_RESCHED 233 jo sysc_reschedule 234 tm __TI_flags+3(%r12),_TIF_SIGPENDING 235 jo sysc_sigpending 236 tm __TI_flags+3(%r12),_TIF_NOTIFY_RESUME 237 jo sysc_notify_resume 238 tm __TI_flags+3(%r12),_TIF_PER_TRAP 239 jo sysc_singlestep 240 j sysc_return # beware of critical section cleanup 241 242# 243# _TIF_NEED_RESCHED is set, call schedule 244# 245sysc_reschedule: 246 l %r1,BASED(.Lschedule) 247 la %r14,BASED(sysc_return) 248 br %r1 # call schedule 249 250# 251# _TIF_MCCK_PENDING is set, call handler 252# 253sysc_mcck_pending: 254 l %r1,BASED(.Lhandle_mcck) 255 la %r14,BASED(sysc_return) 256 br %r1 # TIF bit will be cleared by handler 257 258# 259# _TIF_SIGPENDING is set, call do_signal 260# 261sysc_sigpending: 262 ni __TI_flags+3(%r12),255-_TIF_PER_TRAP # clear TIF_PER_TRAP 263 lr %r2,%r11 # pass pointer to pt_regs 264 l %r1,BASED(.Ldo_signal) 265 basr %r14,%r1 # call do_signal 266 tm __TI_flags+3(%r12),_TIF_SYSCALL 267 jno sysc_return 268 lm %r2,%r7,__PT_R2(%r11) # load svc arguments 269 xr %r8,%r8 # svc 0 returns -ENOSYS 270 clc __PT_INT_CODE+2(2,%r11),BASED(.Lnr_syscalls+2) 271 jnl sysc_nr_ok # invalid svc number -> do svc 0 272 lh %r8,__PT_INT_CODE+2(%r11) # load new svc number 273 sla %r8,2 274 j sysc_nr_ok # restart svc 275 276# 277# _TIF_NOTIFY_RESUME is set, call do_notify_resume 278# 279sysc_notify_resume: 280 lr %r2,%r11 # pass pointer to pt_regs 281 l %r1,BASED(.Ldo_notify_resume) 282 la %r14,BASED(sysc_return) 283 br %r1 # call do_notify_resume 284 285# 286# _TIF_PER_TRAP is set, call do_per_trap 287# 288sysc_singlestep: 289 ni __TI_flags+3(%r12),255-(_TIF_SYSCALL | _TIF_PER_TRAP) 290 lr %r2,%r11 # pass pointer to pt_regs 291 l %r1,BASED(.Ldo_per_trap) 292 la %r14,BASED(sysc_return) 293 br %r1 # call do_per_trap 294 295# 296# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before 297# and after the system call 298# 299sysc_tracesys: 300 l %r1,BASED(.Ltrace_enter) 301 lr %r2,%r11 # pass pointer to pt_regs 302 la %r3,0 303 xr %r0,%r0 304 icm %r0,3,__PT_INT_CODE+2(%r11) 305 st %r0,__PT_R2(%r11) 306 basr %r14,%r1 # call do_syscall_trace_enter 307 cl %r2,BASED(.Lnr_syscalls) 308 jnl sysc_tracenogo 309 lr %r8,%r2 310 sll %r8,2 311 l %r9,0(%r8,%r10) 312sysc_tracego: 313 lm %r3,%r7,__PT_R3(%r11) 314 st %r7,STACK_FRAME_OVERHEAD(%r15) 315 l %r2,__PT_ORIG_GPR2(%r11) 316 basr %r14,%r9 # call sys_xxx 317 st %r2,__PT_R2(%r11) # store return value 318sysc_tracenogo: 319 tm __TI_flags+2(%r12),_TIF_TRACE >> 8 320 jz sysc_return 321 l %r1,BASED(.Ltrace_exit) 322 lr %r2,%r11 # pass pointer to pt_regs 323 la %r14,BASED(sysc_return) 324 br %r1 # call do_syscall_trace_exit 325 326# 327# a new process exits the kernel with ret_from_fork 328# 329ENTRY(ret_from_fork) 330 la %r11,STACK_FRAME_OVERHEAD(%r15) 331 l %r12,__LC_THREAD_INFO 332 l %r13,__LC_SVC_NEW_PSW+4 333 l %r1,BASED(.Lschedule_tail) 334 basr %r14,%r1 # call schedule_tail 335 TRACE_IRQS_ON 336 ssm __LC_SVC_NEW_PSW # reenable interrupts 337 tm __PT_PSW+1(%r11),0x01 # forking a kernel thread ? 338 jne sysc_tracenogo 339 # it's a kernel thread 340 lm %r9,%r10,__PT_R9(%r11) # load gprs 341ENTRY(kernel_thread_starter) 342 la %r2,0(%r10) 343 basr %r14,%r9 344 j sysc_tracenogo 345 346/* 347 * Program check handler routine 348 */ 349 350ENTRY(pgm_check_handler) 351 stpt __LC_SYNC_ENTER_TIMER 352 stm %r8,%r15,__LC_SAVE_AREA_SYNC 353 l %r12,__LC_THREAD_INFO 354 l %r13,__LC_SVC_NEW_PSW+4 355 lm %r8,%r9,__LC_PGM_OLD_PSW 356 tmh %r8,0x0001 # test problem state bit 357 jnz 1f # -> fault in user space 358 tmh %r8,0x4000 # PER bit set in old PSW ? 359 jnz 0f # -> enabled, can't be a double fault 360 tm __LC_PGM_ILC+3,0x80 # check for per exception 361 jnz pgm_svcper # -> single stepped svc 3620: CHECK_STACK STACK_SIZE,__LC_SAVE_AREA_SYNC 363 j 2f 3641: UPDATE_VTIME %r14,%r15,__LC_SYNC_ENTER_TIMER 365 l %r15,__LC_KERNEL_STACK 3662: ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) 367 la %r11,STACK_FRAME_OVERHEAD(%r15) 368 stm %r0,%r7,__PT_R0(%r11) 369 mvc __PT_R8(32,%r11),__LC_SAVE_AREA_SYNC 370 stm %r8,%r9,__PT_PSW(%r11) 371 mvc __PT_INT_CODE(4,%r11),__LC_PGM_ILC 372 mvc __PT_INT_PARM_LONG(4,%r11),__LC_TRANS_EXC_CODE 373 tm __LC_PGM_ILC+3,0x80 # check for per exception 374 jz 0f 375 l %r1,__TI_task(%r12) 376 tmh %r8,0x0001 # kernel per event ? 377 jz pgm_kprobe 378 oi __TI_flags+3(%r12),_TIF_PER_TRAP 379 mvc __THREAD_per_address(4,%r1),__LC_PER_ADDRESS 380 mvc __THREAD_per_cause(2,%r1),__LC_PER_CAUSE 381 mvc __THREAD_per_paid(1,%r1),__LC_PER_PAID 3820: REENABLE_IRQS 383 xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) 384 l %r1,BASED(.Ljump_table) 385 la %r10,0x7f 386 n %r10,__PT_INT_CODE(%r11) 387 je sysc_return 388 sll %r10,2 389 l %r1,0(%r10,%r1) # load address of handler routine 390 lr %r2,%r11 # pass pointer to pt_regs 391 basr %r14,%r1 # branch to interrupt-handler 392 j sysc_return 393 394# 395# PER event in supervisor state, must be kprobes 396# 397pgm_kprobe: 398 REENABLE_IRQS 399 xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) 400 l %r1,BASED(.Ldo_per_trap) 401 lr %r2,%r11 # pass pointer to pt_regs 402 basr %r14,%r1 # call do_per_trap 403 j sysc_return 404 405# 406# single stepped system call 407# 408pgm_svcper: 409 oi __TI_flags+3(%r12),_TIF_PER_TRAP 410 mvc __LC_RETURN_PSW(4),__LC_SVC_NEW_PSW 411 mvc __LC_RETURN_PSW+4(4),BASED(.Lsysc_per) 412 lpsw __LC_RETURN_PSW # branch to sysc_per and enable irqs 413 414/* 415 * IO interrupt handler routine 416 */ 417 418ENTRY(io_int_handler) 419 stck __LC_INT_CLOCK 420 stpt __LC_ASYNC_ENTER_TIMER 421 stm %r8,%r15,__LC_SAVE_AREA_ASYNC 422 l %r12,__LC_THREAD_INFO 423 l %r13,__LC_SVC_NEW_PSW+4 424 lm %r8,%r9,__LC_IO_OLD_PSW 425 tmh %r8,0x0001 # interrupting from user ? 426 jz io_skip 427 UPDATE_VTIME %r14,%r15,__LC_ASYNC_ENTER_TIMER 428io_skip: 429 SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT 430 stm %r0,%r7,__PT_R0(%r11) 431 mvc __PT_R8(32,%r11),__LC_SAVE_AREA_ASYNC 432 stm %r8,%r9,__PT_PSW(%r11) 433 TRACE_IRQS_OFF 434 xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) 435 l %r1,BASED(.Ldo_IRQ) 436 lr %r2,%r11 # pass pointer to pt_regs 437 basr %r14,%r1 # call do_IRQ 438io_return: 439 LOCKDEP_SYS_EXIT 440 TRACE_IRQS_ON 441io_tif: 442 tm __TI_flags+3(%r12),_TIF_WORK_INT 443 jnz io_work # there is work to do (signals etc.) 444io_restore: 445 mvc __LC_RETURN_PSW(8),__PT_PSW(%r11) 446 stpt __LC_EXIT_TIMER 447 lm %r0,%r15,__PT_R0(%r11) 448 lpsw __LC_RETURN_PSW 449io_done: 450 451# 452# There is work todo, find out in which context we have been interrupted: 453# 1) if we return to user space we can do all _TIF_WORK_INT work 454# 2) if we return to kernel code and preemptive scheduling is enabled check 455# the preemption counter and if it is zero call preempt_schedule_irq 456# Before any work can be done, a switch to the kernel stack is required. 457# 458io_work: 459 tm __PT_PSW+1(%r11),0x01 # returning to user ? 460 jo io_work_user # yes -> do resched & signal 461#ifdef CONFIG_PREEMPT 462 # check for preemptive scheduling 463 icm %r0,15,__TI_precount(%r12) 464 jnz io_restore # preemption disabled 465 tm __TI_flags+3(%r12),_TIF_NEED_RESCHED 466 jno io_restore 467 # switch to kernel stack 468 l %r1,__PT_R15(%r11) 469 ahi %r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE) 470 mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11) 471 xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) 472 la %r11,STACK_FRAME_OVERHEAD(%r1) 473 lr %r15,%r1 474 # TRACE_IRQS_ON already done at io_return, call 475 # TRACE_IRQS_OFF to keep things symmetrical 476 TRACE_IRQS_OFF 477 l %r1,BASED(.Lpreempt_irq) 478 basr %r14,%r1 # call preempt_schedule_irq 479 j io_return 480#else 481 j io_restore 482#endif 483 484# 485# Need to do work before returning to userspace, switch to kernel stack 486# 487io_work_user: 488 l %r1,__LC_KERNEL_STACK 489 ahi %r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE) 490 mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11) 491 xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) 492 la %r11,STACK_FRAME_OVERHEAD(%r1) 493 lr %r15,%r1 494 495# 496# One of the work bits is on. Find out which one. 497# Checked are: _TIF_SIGPENDING, _TIF_NOTIFY_RESUME, _TIF_NEED_RESCHED 498# and _TIF_MCCK_PENDING 499# 500io_work_tif: 501 tm __TI_flags+3(%r12),_TIF_MCCK_PENDING 502 jo io_mcck_pending 503 tm __TI_flags+3(%r12),_TIF_NEED_RESCHED 504 jo io_reschedule 505 tm __TI_flags+3(%r12),_TIF_SIGPENDING 506 jo io_sigpending 507 tm __TI_flags+3(%r12),_TIF_NOTIFY_RESUME 508 jo io_notify_resume 509 j io_return # beware of critical section cleanup 510 511# 512# _TIF_MCCK_PENDING is set, call handler 513# 514io_mcck_pending: 515 # TRACE_IRQS_ON already done at io_return 516 l %r1,BASED(.Lhandle_mcck) 517 basr %r14,%r1 # TIF bit will be cleared by handler 518 TRACE_IRQS_OFF 519 j io_return 520 521# 522# _TIF_NEED_RESCHED is set, call schedule 523# 524io_reschedule: 525 # TRACE_IRQS_ON already done at io_return 526 l %r1,BASED(.Lschedule) 527 ssm __LC_SVC_NEW_PSW # reenable interrupts 528 basr %r14,%r1 # call scheduler 529 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts 530 TRACE_IRQS_OFF 531 j io_return 532 533# 534# _TIF_SIGPENDING is set, call do_signal 535# 536io_sigpending: 537 # TRACE_IRQS_ON already done at io_return 538 l %r1,BASED(.Ldo_signal) 539 ssm __LC_SVC_NEW_PSW # reenable interrupts 540 lr %r2,%r11 # pass pointer to pt_regs 541 basr %r14,%r1 # call do_signal 542 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts 543 TRACE_IRQS_OFF 544 j io_return 545 546# 547# _TIF_SIGPENDING is set, call do_signal 548# 549io_notify_resume: 550 # TRACE_IRQS_ON already done at io_return 551 l %r1,BASED(.Ldo_notify_resume) 552 ssm __LC_SVC_NEW_PSW # reenable interrupts 553 lr %r2,%r11 # pass pointer to pt_regs 554 basr %r14,%r1 # call do_notify_resume 555 ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts 556 TRACE_IRQS_OFF 557 j io_return 558 559/* 560 * External interrupt handler routine 561 */ 562 563ENTRY(ext_int_handler) 564 stck __LC_INT_CLOCK 565 stpt __LC_ASYNC_ENTER_TIMER 566 stm %r8,%r15,__LC_SAVE_AREA_ASYNC 567 l %r12,__LC_THREAD_INFO 568 l %r13,__LC_SVC_NEW_PSW+4 569 lm %r8,%r9,__LC_EXT_OLD_PSW 570 tmh %r8,0x0001 # interrupting from user ? 571 jz ext_skip 572 UPDATE_VTIME %r14,%r15,__LC_ASYNC_ENTER_TIMER 573ext_skip: 574 SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT 575 stm %r0,%r7,__PT_R0(%r11) 576 mvc __PT_R8(32,%r11),__LC_SAVE_AREA_ASYNC 577 stm %r8,%r9,__PT_PSW(%r11) 578 TRACE_IRQS_OFF 579 lr %r2,%r11 # pass pointer to pt_regs 580 l %r3,__LC_EXT_CPU_ADDR # get cpu address + interruption code 581 l %r4,__LC_EXT_PARAMS # get external parameters 582 l %r1,BASED(.Ldo_extint) 583 basr %r14,%r1 # call do_extint 584 j io_return 585 586/* 587 * Load idle PSW. The second "half" of this function is in cleanup_idle. 588 */ 589ENTRY(psw_idle) 590 st %r3,__SF_EMPTY(%r15) 591 basr %r1,0 592 la %r1,psw_idle_lpsw+4-.(%r1) 593 st %r1,__SF_EMPTY+4(%r15) 594 oi __SF_EMPTY+4(%r15),0x80 595 stck __CLOCK_IDLE_ENTER(%r2) 596 stpt __TIMER_IDLE_ENTER(%r2) 597psw_idle_lpsw: 598 lpsw __SF_EMPTY(%r15) 599 br %r14 600psw_idle_end: 601 602__critical_end: 603 604/* 605 * Machine check handler routines 606 */ 607 608ENTRY(mcck_int_handler) 609 stck __LC_MCCK_CLOCK 610 spt __LC_CPU_TIMER_SAVE_AREA # revalidate cpu timer 611 lm %r0,%r15,__LC_GPREGS_SAVE_AREA # revalidate gprs 612 l %r12,__LC_THREAD_INFO 613 l %r13,__LC_SVC_NEW_PSW+4 614 lm %r8,%r9,__LC_MCK_OLD_PSW 615 tm __LC_MCCK_CODE,0x80 # system damage? 616 jo mcck_panic # yes -> rest of mcck code invalid 617 la %r14,__LC_CPU_TIMER_SAVE_AREA 618 mvc __LC_MCCK_ENTER_TIMER(8),0(%r14) 619 tm __LC_MCCK_CODE+5,0x02 # stored cpu timer value valid? 620 jo 3f 621 la %r14,__LC_SYNC_ENTER_TIMER 622 clc 0(8,%r14),__LC_ASYNC_ENTER_TIMER 623 jl 0f 624 la %r14,__LC_ASYNC_ENTER_TIMER 6250: clc 0(8,%r14),__LC_EXIT_TIMER 626 jl 1f 627 la %r14,__LC_EXIT_TIMER 6281: clc 0(8,%r14),__LC_LAST_UPDATE_TIMER 629 jl 2f 630 la %r14,__LC_LAST_UPDATE_TIMER 6312: spt 0(%r14) 632 mvc __LC_MCCK_ENTER_TIMER(8),0(%r14) 6333: tm __LC_MCCK_CODE+2,0x09 # mwp + ia of old psw valid? 634 jno mcck_panic # no -> skip cleanup critical 635 tm %r8,0x0001 # interrupting from user ? 636 jz mcck_skip 637 UPDATE_VTIME %r14,%r15,__LC_MCCK_ENTER_TIMER 638mcck_skip: 639 SWITCH_ASYNC __LC_GPREGS_SAVE_AREA+32,__LC_PANIC_STACK,PAGE_SHIFT 640 mvc __PT_R0(64,%r11),__LC_GPREGS_SAVE_AREA 641 stm %r8,%r9,__PT_PSW(%r11) 642 xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) 643 l %r1,BASED(.Ldo_machine_check) 644 lr %r2,%r11 # pass pointer to pt_regs 645 basr %r14,%r1 # call s390_do_machine_check 646 tm __PT_PSW+1(%r11),0x01 # returning to user ? 647 jno mcck_return 648 l %r1,__LC_KERNEL_STACK # switch to kernel stack 649 ahi %r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE) 650 mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11) 651 xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) 652 la %r11,STACK_FRAME_OVERHEAD(%r15) 653 lr %r15,%r1 654 ssm __LC_PGM_NEW_PSW # turn dat on, keep irqs off 655 tm __TI_flags+3(%r12),_TIF_MCCK_PENDING 656 jno mcck_return 657 TRACE_IRQS_OFF 658 l %r1,BASED(.Lhandle_mcck) 659 basr %r14,%r1 # call s390_handle_mcck 660 TRACE_IRQS_ON 661mcck_return: 662 mvc __LC_RETURN_MCCK_PSW(8),__PT_PSW(%r11) # move return PSW 663 tm __LC_RETURN_MCCK_PSW+1,0x01 # returning to user ? 664 jno 0f 665 lm %r0,%r15,__PT_R0(%r11) 666 stpt __LC_EXIT_TIMER 667 lpsw __LC_RETURN_MCCK_PSW 6680: lm %r0,%r15,__PT_R0(%r11) 669 lpsw __LC_RETURN_MCCK_PSW 670 671mcck_panic: 672 l %r14,__LC_PANIC_STACK 673 slr %r14,%r15 674 sra %r14,PAGE_SHIFT 675 jz 0f 676 l %r15,__LC_PANIC_STACK 6770: ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) 678 j mcck_skip 679 680# 681# PSW restart interrupt handler 682# 683ENTRY(restart_int_handler) 684 st %r15,__LC_SAVE_AREA_RESTART 685 l %r15,__LC_RESTART_STACK 686 ahi %r15,-__PT_SIZE # create pt_regs on stack 687 xc 0(__PT_SIZE,%r15),0(%r15) 688 stm %r0,%r14,__PT_R0(%r15) 689 mvc __PT_R15(4,%r15),__LC_SAVE_AREA_RESTART 690 mvc __PT_PSW(8,%r15),__LC_RST_OLD_PSW # store restart old psw 691 ahi %r15,-STACK_FRAME_OVERHEAD # create stack frame on stack 692 xc 0(STACK_FRAME_OVERHEAD,%r15),0(%r15) 693 l %r1,__LC_RESTART_FN # load fn, parm & source cpu 694 l %r2,__LC_RESTART_DATA 695 l %r3,__LC_RESTART_SOURCE 696 ltr %r3,%r3 # test source cpu address 697 jm 1f # negative -> skip source stop 6980: sigp %r4,%r3,SIGP_SENSE # sigp sense to source cpu 699 brc 10,0b # wait for status stored 7001: basr %r14,%r1 # call function 701 stap __SF_EMPTY(%r15) # store cpu address 702 lh %r3,__SF_EMPTY(%r15) 7032: sigp %r4,%r3,SIGP_STOP # sigp stop to current cpu 704 brc 2,2b 7053: j 3b 706 707 .section .kprobes.text, "ax" 708 709#ifdef CONFIG_CHECK_STACK 710/* 711 * The synchronous or the asynchronous stack overflowed. We are dead. 712 * No need to properly save the registers, we are going to panic anyway. 713 * Setup a pt_regs so that show_trace can provide a good call trace. 714 */ 715stack_overflow: 716 l %r15,__LC_PANIC_STACK # change to panic stack 717 ahi %r15,-__PT_SIZE # create pt_regs 718 stm %r0,%r7,__PT_R0(%r15) 719 stm %r8,%r9,__PT_PSW(%r15) 720 mvc __PT_R8(32,%r11),0(%r14) 721 lr %r15,%r11 722 ahi %r15,-STACK_FRAME_OVERHEAD 723 l %r1,BASED(1f) 724 xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) 725 lr %r2,%r11 # pass pointer to pt_regs 726 br %r1 # branch to kernel_stack_overflow 7271: .long kernel_stack_overflow 728#endif 729 730cleanup_table: 731 .long system_call + 0x80000000 732 .long sysc_do_svc + 0x80000000 733 .long sysc_tif + 0x80000000 734 .long sysc_restore + 0x80000000 735 .long sysc_done + 0x80000000 736 .long io_tif + 0x80000000 737 .long io_restore + 0x80000000 738 .long io_done + 0x80000000 739 .long psw_idle + 0x80000000 740 .long psw_idle_end + 0x80000000 741 742cleanup_critical: 743 cl %r9,BASED(cleanup_table) # system_call 744 jl 0f 745 cl %r9,BASED(cleanup_table+4) # sysc_do_svc 746 jl cleanup_system_call 747 cl %r9,BASED(cleanup_table+8) # sysc_tif 748 jl 0f 749 cl %r9,BASED(cleanup_table+12) # sysc_restore 750 jl cleanup_sysc_tif 751 cl %r9,BASED(cleanup_table+16) # sysc_done 752 jl cleanup_sysc_restore 753 cl %r9,BASED(cleanup_table+20) # io_tif 754 jl 0f 755 cl %r9,BASED(cleanup_table+24) # io_restore 756 jl cleanup_io_tif 757 cl %r9,BASED(cleanup_table+28) # io_done 758 jl cleanup_io_restore 759 cl %r9,BASED(cleanup_table+32) # psw_idle 760 jl 0f 761 cl %r9,BASED(cleanup_table+36) # psw_idle_end 762 jl cleanup_idle 7630: br %r14 764 765cleanup_system_call: 766 # check if stpt has been executed 767 cl %r9,BASED(cleanup_system_call_insn) 768 jh 0f 769 mvc __LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER 770 chi %r11,__LC_SAVE_AREA_ASYNC 771 je 0f 772 mvc __LC_SYNC_ENTER_TIMER(8),__LC_MCCK_ENTER_TIMER 7730: # check if stm has been executed 774 cl %r9,BASED(cleanup_system_call_insn+4) 775 jh 0f 776 mvc __LC_SAVE_AREA_SYNC(32),0(%r11) 7770: # set up saved registers r12, and r13 778 st %r12,16(%r11) # r12 thread-info pointer 779 st %r13,20(%r11) # r13 literal-pool pointer 780 # check if the user time calculation has been done 781 cl %r9,BASED(cleanup_system_call_insn+8) 782 jh 0f 783 l %r10,__LC_EXIT_TIMER 784 l %r15,__LC_EXIT_TIMER+4 785 SUB64 %r10,%r15,__LC_SYNC_ENTER_TIMER 786 ADD64 %r10,%r15,__LC_USER_TIMER 787 st %r10,__LC_USER_TIMER 788 st %r15,__LC_USER_TIMER+4 7890: # check if the system time calculation has been done 790 cl %r9,BASED(cleanup_system_call_insn+12) 791 jh 0f 792 l %r10,__LC_LAST_UPDATE_TIMER 793 l %r15,__LC_LAST_UPDATE_TIMER+4 794 SUB64 %r10,%r15,__LC_EXIT_TIMER 795 ADD64 %r10,%r15,__LC_SYSTEM_TIMER 796 st %r10,__LC_SYSTEM_TIMER 797 st %r15,__LC_SYSTEM_TIMER+4 7980: # update accounting time stamp 799 mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER 800 # set up saved register 11 801 l %r15,__LC_KERNEL_STACK 802 ahi %r15,-__PT_SIZE 803 st %r15,12(%r11) # r11 pt_regs pointer 804 # fill pt_regs 805 mvc __PT_R8(32,%r15),__LC_SAVE_AREA_SYNC 806 stm %r0,%r7,__PT_R0(%r15) 807 mvc __PT_PSW(8,%r15),__LC_SVC_OLD_PSW 808 mvc __PT_INT_CODE(4,%r15),__LC_SVC_ILC 809 # setup saved register 15 810 ahi %r15,-STACK_FRAME_OVERHEAD 811 st %r15,28(%r11) # r15 stack pointer 812 # set new psw address and exit 813 l %r9,BASED(cleanup_table+4) # sysc_do_svc + 0x80000000 814 br %r14 815cleanup_system_call_insn: 816 .long system_call + 0x80000000 817 .long sysc_stm + 0x80000000 818 .long sysc_vtime + 0x80000000 + 36 819 .long sysc_vtime + 0x80000000 + 76 820 821cleanup_sysc_tif: 822 l %r9,BASED(cleanup_table+8) # sysc_tif + 0x80000000 823 br %r14 824 825cleanup_sysc_restore: 826 cl %r9,BASED(cleanup_sysc_restore_insn) 827 jhe 0f 828 l %r9,12(%r11) # get saved pointer to pt_regs 829 mvc __LC_RETURN_PSW(8),__PT_PSW(%r9) 830 mvc 0(32,%r11),__PT_R8(%r9) 831 lm %r0,%r7,__PT_R0(%r9) 8320: lm %r8,%r9,__LC_RETURN_PSW 833 br %r14 834cleanup_sysc_restore_insn: 835 .long sysc_done - 4 + 0x80000000 836 837cleanup_io_tif: 838 l %r9,BASED(cleanup_table+20) # io_tif + 0x80000000 839 br %r14 840 841cleanup_io_restore: 842 cl %r9,BASED(cleanup_io_restore_insn) 843 jhe 0f 844 l %r9,12(%r11) # get saved r11 pointer to pt_regs 845 mvc __LC_RETURN_PSW(8),__PT_PSW(%r9) 846 mvc 0(32,%r11),__PT_R8(%r9) 847 lm %r0,%r7,__PT_R0(%r9) 8480: lm %r8,%r9,__LC_RETURN_PSW 849 br %r14 850cleanup_io_restore_insn: 851 .long io_done - 4 + 0x80000000 852 853cleanup_idle: 854 # copy interrupt clock & cpu timer 855 mvc __CLOCK_IDLE_EXIT(8,%r2),__LC_INT_CLOCK 856 mvc __TIMER_IDLE_EXIT(8,%r2),__LC_ASYNC_ENTER_TIMER 857 chi %r11,__LC_SAVE_AREA_ASYNC 858 je 0f 859 mvc __CLOCK_IDLE_EXIT(8,%r2),__LC_MCCK_CLOCK 860 mvc __TIMER_IDLE_EXIT(8,%r2),__LC_MCCK_ENTER_TIMER 8610: # check if stck has been executed 862 cl %r9,BASED(cleanup_idle_insn) 863 jhe 1f 864 mvc __CLOCK_IDLE_ENTER(8,%r2),__CLOCK_IDLE_EXIT(%r2) 865 mvc __TIMER_IDLE_ENTER(8,%r2),__TIMER_IDLE_EXIT(%r3) 8661: # account system time going idle 867 lm %r9,%r10,__LC_STEAL_TIMER 868 ADD64 %r9,%r10,__CLOCK_IDLE_ENTER(%r2) 869 SUB64 %r9,%r10,__LC_LAST_UPDATE_CLOCK 870 stm %r9,%r10,__LC_STEAL_TIMER 871 mvc __LC_LAST_UPDATE_CLOCK(8),__CLOCK_IDLE_EXIT(%r2) 872 lm %r9,%r10,__LC_SYSTEM_TIMER 873 ADD64 %r9,%r10,__LC_LAST_UPDATE_TIMER 874 SUB64 %r9,%r10,__TIMER_IDLE_ENTER(%r2) 875 stm %r9,%r10,__LC_SYSTEM_TIMER 876 mvc __LC_LAST_UPDATE_TIMER(8),__TIMER_IDLE_EXIT(%r2) 877 # prepare return psw 878 n %r8,BASED(cleanup_idle_wait) # clear wait state bit 879 l %r9,24(%r11) # return from psw_idle 880 br %r14 881cleanup_idle_insn: 882 .long psw_idle_lpsw + 0x80000000 883cleanup_idle_wait: 884 .long 0xfffdffff 885 886/* 887 * Integer constants 888 */ 889 .align 4 890.Lnr_syscalls: 891 .long NR_syscalls 892.Lvtimer_max: 893 .quad 0x7fffffffffffffff 894 895/* 896 * Symbol constants 897 */ 898.Ldo_machine_check: .long s390_do_machine_check 899.Lhandle_mcck: .long s390_handle_mcck 900.Ldo_IRQ: .long do_IRQ 901.Ldo_extint: .long do_extint 902.Ldo_signal: .long do_signal 903.Ldo_notify_resume: .long do_notify_resume 904.Ldo_per_trap: .long do_per_trap 905.Ljump_table: .long pgm_check_table 906.Lschedule: .long schedule 907#ifdef CONFIG_PREEMPT 908.Lpreempt_irq: .long preempt_schedule_irq 909#endif 910.Ltrace_enter: .long do_syscall_trace_enter 911.Ltrace_exit: .long do_syscall_trace_exit 912.Lschedule_tail: .long schedule_tail 913.Lsys_call_table: .long sys_call_table 914.Lsysc_per: .long sysc_per + 0x80000000 915#ifdef CONFIG_TRACE_IRQFLAGS 916.Lhardirqs_on: .long trace_hardirqs_on_caller 917.Lhardirqs_off: .long trace_hardirqs_off_caller 918#endif 919#ifdef CONFIG_LOCKDEP 920.Llockdep_sys_exit: .long lockdep_sys_exit 921#endif 922.Lcritical_start: .long __critical_start + 0x80000000 923.Lcritical_length: .long __critical_end - __critical_start 924 925 .section .rodata, "a" 926#define SYSCALL(esa,esame,emu) .long esa 927 .globl sys_call_table 928sys_call_table: 929#include "syscalls.S" 930#undef SYSCALL 931