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 964