diff options
Diffstat (limited to 'arch/s390/kernel/entry.S')
| -rw-r--r-- | arch/s390/kernel/entry.S | 967 |
1 files changed, 967 insertions, 0 deletions
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S new file mode 100644 index 00000000..74ee563f --- /dev/null +++ b/arch/s390/kernel/entry.S @@ -0,0 +1,967 @@ +/* + * arch/s390/kernel/entry.S + * S390 low-level entry points. + * + * Copyright (C) IBM Corp. 1999,2012 + * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com), + * Hartmut Penner (hp@de.ibm.com), + * Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com), + * Heiko Carstens <heiko.carstens@de.ibm.com> + */ + +#include <linux/init.h> +#include <linux/linkage.h> +#include <asm/cache.h> +#include <asm/errno.h> +#include <asm/ptrace.h> +#include <asm/thread_info.h> +#include <asm/asm-offsets.h> +#include <asm/unistd.h> +#include <asm/page.h> + +__PT_R0 = __PT_GPRS +__PT_R1 = __PT_GPRS + 4 +__PT_R2 = __PT_GPRS + 8 +__PT_R3 = __PT_GPRS + 12 +__PT_R4 = __PT_GPRS + 16 +__PT_R5 = __PT_GPRS + 20 +__PT_R6 = __PT_GPRS + 24 +__PT_R7 = __PT_GPRS + 28 +__PT_R8 = __PT_GPRS + 32 +__PT_R9 = __PT_GPRS + 36 +__PT_R10 = __PT_GPRS + 40 +__PT_R11 = __PT_GPRS + 44 +__PT_R12 = __PT_GPRS + 48 +__PT_R13 = __PT_GPRS + 524 +__PT_R14 = __PT_GPRS + 56 +__PT_R15 = __PT_GPRS + 60 + +_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \ + _TIF_MCCK_PENDING | _TIF_PER_TRAP ) +_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \ + _TIF_MCCK_PENDING) +_TIF_TRACE = (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | \ + _TIF_SYSCALL_TRACEPOINT) + +STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER +STACK_SIZE = 1 << STACK_SHIFT + +#define BASED(name) name-system_call(%r13) + + .macro TRACE_IRQS_ON +#ifdef CONFIG_TRACE_IRQFLAGS + basr %r2,%r0 + l %r1,BASED(.Lhardirqs_on) + basr %r14,%r1 # call trace_hardirqs_on_caller +#endif + .endm + + .macro TRACE_IRQS_OFF +#ifdef CONFIG_TRACE_IRQFLAGS + basr %r2,%r0 + l %r1,BASED(.Lhardirqs_off) + basr %r14,%r1 # call trace_hardirqs_off_caller +#endif + .endm + + .macro LOCKDEP_SYS_EXIT +#ifdef CONFIG_LOCKDEP + tm __PT_PSW+1(%r11),0x01 # returning to user ? + jz .+10 + l %r1,BASED(.Llockdep_sys_exit) + basr %r14,%r1 # call lockdep_sys_exit +#endif + .endm + + .macro CHECK_STACK stacksize,savearea +#ifdef CONFIG_CHECK_STACK + tml %r15,\stacksize - CONFIG_STACK_GUARD + la %r14,\savearea + jz stack_overflow +#endif + .endm + + .macro SWITCH_ASYNC savearea,stack,shift + tmh %r8,0x0001 # interrupting from user ? + jnz 1f + lr %r14,%r9 + sl %r14,BASED(.Lcritical_start) + cl %r14,BASED(.Lcritical_length) + jhe 0f + la %r11,\savearea # inside critical section, do cleanup + bras %r14,cleanup_critical + tmh %r8,0x0001 # retest problem state after cleanup + jnz 1f +0: l %r14,\stack # are we already on the target stack? + slr %r14,%r15 + sra %r14,\shift + jnz 1f + CHECK_STACK 1<<\shift,\savearea + j 2f +1: l %r15,\stack # load target stack +2: ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) + la %r11,STACK_FRAME_OVERHEAD(%r15) + .endm + + .macro ADD64 high,low,timer + al \high,\timer + al \low,4+\timer + brc 12,.+8 + ahi \high,1 + .endm + + .macro SUB64 high,low,timer + sl \high,\timer + sl \low,4+\timer + brc 3,.+8 + ahi \high,-1 + .endm + + .macro UPDATE_VTIME high,low,enter_timer + lm \high,\low,__LC_EXIT_TIMER + SUB64 \high,\low,\enter_timer + ADD64 \high,\low,__LC_USER_TIMER + stm \high,\low,__LC_USER_TIMER + lm \high,\low,__LC_LAST_UPDATE_TIMER + SUB64 \high,\low,__LC_EXIT_TIMER + ADD64 \high,\low,__LC_SYSTEM_TIMER + stm \high,\low,__LC_SYSTEM_TIMER + mvc __LC_LAST_UPDATE_TIMER(8),\enter_timer + .endm + + .macro REENABLE_IRQS + st %r8,__LC_RETURN_PSW + ni __LC_RETURN_PSW,0xbf + ssm __LC_RETURN_PSW + .endm + + .section .kprobes.text, "ax" + +/* + * Scheduler resume function, called by switch_to + * gpr2 = (task_struct *) prev + * gpr3 = (task_struct *) next + * Returns: + * gpr2 = prev + */ +ENTRY(__switch_to) + l %r4,__THREAD_info(%r2) # get thread_info of prev + l %r5,__THREAD_info(%r3) # get thread_info of next + tm __TI_flags+3(%r4),_TIF_MCCK_PENDING # machine check pending? + jz 0f + ni __TI_flags+3(%r4),255-_TIF_MCCK_PENDING # clear flag in prev + oi __TI_flags+3(%r5),_TIF_MCCK_PENDING # set it in next +0: stm %r6,%r15,__SF_GPRS(%r15) # store gprs of prev task + st %r15,__THREAD_ksp(%r2) # store kernel stack of prev + l %r15,__THREAD_ksp(%r3) # load kernel stack of next + lctl %c4,%c4,__TASK_pid(%r3) # load pid to control reg. 4 + lm %r6,%r15,__SF_GPRS(%r15) # load gprs of next task + st %r3,__LC_CURRENT # store task struct of next + mvc __LC_CURRENT_PID(4,%r0),__TASK_pid(%r3) # store pid of next + st %r5,__LC_THREAD_INFO # store thread info of next + ahi %r5,STACK_SIZE # end of kernel stack of next + st %r5,__LC_KERNEL_STACK # store end of kernel stack + br %r14 + +__critical_start: +/* + * SVC interrupt handler routine. System calls are synchronous events and + * are executed with interrupts enabled. + */ + +ENTRY(system_call) + stpt __LC_SYNC_ENTER_TIMER +sysc_stm: + stm %r8,%r15,__LC_SAVE_AREA_SYNC + l %r12,__LC_THREAD_INFO + l %r13,__LC_SVC_NEW_PSW+4 +sysc_per: + l %r15,__LC_KERNEL_STACK + ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) + la %r11,STACK_FRAME_OVERHEAD(%r15) # pointer to pt_regs +sysc_vtime: + UPDATE_VTIME %r8,%r9,__LC_SYNC_ENTER_TIMER + stm %r0,%r7,__PT_R0(%r11) + mvc __PT_R8(32,%r11),__LC_SAVE_AREA_SYNC + mvc __PT_PSW(8,%r11),__LC_SVC_OLD_PSW + mvc __PT_INT_CODE(4,%r11),__LC_SVC_ILC +sysc_do_svc: + oi __TI_flags+3(%r12),_TIF_SYSCALL + lh %r8,__PT_INT_CODE+2(%r11) + sla %r8,2 # shift and test for svc0 + jnz sysc_nr_ok + # svc 0: system call number in %r1 + cl %r1,BASED(.Lnr_syscalls) + jnl sysc_nr_ok + sth %r1,__PT_INT_CODE+2(%r11) + lr %r8,%r1 + sla %r8,2 +sysc_nr_ok: + l %r10,BASED(.Lsys_call_table) # 31 bit system call table + xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) + st %r2,__PT_ORIG_GPR2(%r11) + st %r7,STACK_FRAME_OVERHEAD(%r15) + l %r9,0(%r8,%r10) # get system call addr. + tm __TI_flags+2(%r12),_TIF_TRACE >> 8 + jnz sysc_tracesys + basr %r14,%r9 # call sys_xxxx + st %r2,__PT_R2(%r11) # store return value + +sysc_return: + LOCKDEP_SYS_EXIT +sysc_tif: + tm __PT_PSW+1(%r11),0x01 # returning to user ? + jno sysc_restore + tm __TI_flags+3(%r12),_TIF_WORK_SVC + jnz sysc_work # check for work + ni __TI_flags+3(%r12),255-_TIF_SYSCALL +sysc_restore: + mvc __LC_RETURN_PSW(8),__PT_PSW(%r11) + stpt __LC_EXIT_TIMER + lm %r0,%r15,__PT_R0(%r11) + lpsw __LC_RETURN_PSW +sysc_done: + +# +# One of the work bits is on. Find out which one. +# +sysc_work: + tm __TI_flags+3(%r12),_TIF_MCCK_PENDING + jo sysc_mcck_pending + tm __TI_flags+3(%r12),_TIF_NEED_RESCHED + jo sysc_reschedule + tm __TI_flags+3(%r12),_TIF_SIGPENDING + jo sysc_sigpending + tm __TI_flags+3(%r12),_TIF_NOTIFY_RESUME + jo sysc_notify_resume + tm __TI_flags+3(%r12),_TIF_PER_TRAP + jo sysc_singlestep + j sysc_return # beware of critical section cleanup + +# +# _TIF_NEED_RESCHED is set, call schedule +# +sysc_reschedule: + l %r1,BASED(.Lschedule) + la %r14,BASED(sysc_return) + br %r1 # call schedule + +# +# _TIF_MCCK_PENDING is set, call handler +# +sysc_mcck_pending: + l %r1,BASED(.Lhandle_mcck) + la %r14,BASED(sysc_return) + br %r1 # TIF bit will be cleared by handler + +# +# _TIF_SIGPENDING is set, call do_signal +# +sysc_sigpending: + ni __TI_flags+3(%r12),255-_TIF_PER_TRAP # clear TIF_PER_TRAP + lr %r2,%r11 # pass pointer to pt_regs + l %r1,BASED(.Ldo_signal) + basr %r14,%r1 # call do_signal + tm __TI_flags+3(%r12),_TIF_SYSCALL + jno sysc_return + lm %r2,%r7,__PT_R2(%r11) # load svc arguments + xr %r8,%r8 # svc 0 returns -ENOSYS + clc __PT_INT_CODE+2(2,%r11),BASED(.Lnr_syscalls+2) + jnl sysc_nr_ok # invalid svc number -> do svc 0 + lh %r8,__PT_INT_CODE+2(%r11) # load new svc number + sla %r8,2 + j sysc_nr_ok # restart svc + +# +# _TIF_NOTIFY_RESUME is set, call do_notify_resume +# +sysc_notify_resume: + lr %r2,%r11 # pass pointer to pt_regs + l %r1,BASED(.Ldo_notify_resume) + la %r14,BASED(sysc_return) + br %r1 # call do_notify_resume + +# +# _TIF_PER_TRAP is set, call do_per_trap +# +sysc_singlestep: + ni __TI_flags+3(%r12),255-(_TIF_SYSCALL | _TIF_PER_TRAP) + lr %r2,%r11 # pass pointer to pt_regs + l %r1,BASED(.Ldo_per_trap) + la %r14,BASED(sysc_return) + br %r1 # call do_per_trap + +# +# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before +# and after the system call +# +sysc_tracesys: + l %r1,BASED(.Ltrace_enter) + lr %r2,%r11 # pass pointer to pt_regs + la %r3,0 + xr %r0,%r0 + icm %r0,3,__PT_INT_CODE+2(%r11) + st %r0,__PT_R2(%r11) + basr %r14,%r1 # call do_syscall_trace_enter + cl %r2,BASED(.Lnr_syscalls) + jnl sysc_tracenogo + lr %r8,%r2 + sll %r8,2 + l %r9,0(%r8,%r10) +sysc_tracego: + lm %r3,%r7,__PT_R3(%r11) + st %r7,STACK_FRAME_OVERHEAD(%r15) + l %r2,__PT_ORIG_GPR2(%r11) + basr %r14,%r9 # call sys_xxx + st %r2,__PT_R2(%r11) # store return value +sysc_tracenogo: + tm __TI_flags+2(%r12),_TIF_TRACE >> 8 + jz sysc_return + l %r1,BASED(.Ltrace_exit) + lr %r2,%r11 # pass pointer to pt_regs + la %r14,BASED(sysc_return) + br %r1 # call do_syscall_trace_exit + +# +# a new process exits the kernel with ret_from_fork +# +ENTRY(ret_from_fork) + la %r11,STACK_FRAME_OVERHEAD(%r15) + l %r12,__LC_THREAD_INFO + l %r13,__LC_SVC_NEW_PSW+4 + tm __PT_PSW+1(%r11),0x01 # forking a kernel thread ? + jo 0f + st %r15,__PT_R15(%r11) # store stack pointer for new kthread +0: l %r1,BASED(.Lschedule_tail) + basr %r14,%r1 # call schedule_tail + TRACE_IRQS_ON + ssm __LC_SVC_NEW_PSW # reenable interrupts + j sysc_tracenogo + +# +# kernel_execve function needs to deal with pt_regs that is not +# at the usual place +# +ENTRY(kernel_execve) + stm %r12,%r15,48(%r15) + lr %r14,%r15 + l %r13,__LC_SVC_NEW_PSW+4 + ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) + st %r14,__SF_BACKCHAIN(%r15) + la %r12,STACK_FRAME_OVERHEAD(%r15) + xc 0(__PT_SIZE,%r12),0(%r12) + l %r1,BASED(.Ldo_execve) + lr %r5,%r12 + basr %r14,%r1 # call do_execve + ltr %r2,%r2 + je 0f + ahi %r15,(STACK_FRAME_OVERHEAD + __PT_SIZE) + lm %r12,%r15,48(%r15) + br %r14 + # execve succeeded. +0: ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts + l %r15,__LC_KERNEL_STACK # load ksp + ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) + la %r11,STACK_FRAME_OVERHEAD(%r15) + mvc 0(__PT_SIZE,%r11),0(%r12) # copy pt_regs + l %r12,__LC_THREAD_INFO + xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) + ssm __LC_SVC_NEW_PSW # reenable interrupts + l %r1,BASED(.Lexecve_tail) + basr %r14,%r1 # call execve_tail + j sysc_return + +/* + * Program check handler routine + */ + +ENTRY(pgm_check_handler) + stpt __LC_SYNC_ENTER_TIMER + stm %r8,%r15,__LC_SAVE_AREA_SYNC + l %r12,__LC_THREAD_INFO + l %r13,__LC_SVC_NEW_PSW+4 + lm %r8,%r9,__LC_PGM_OLD_PSW + tmh %r8,0x0001 # test problem state bit + jnz 1f # -> fault in user space + tmh %r8,0x4000 # PER bit set in old PSW ? + jnz 0f # -> enabled, can't be a double fault + tm __LC_PGM_ILC+3,0x80 # check for per exception + jnz pgm_svcper # -> single stepped svc +0: CHECK_STACK STACK_SIZE,__LC_SAVE_AREA_SYNC + j 2f +1: UPDATE_VTIME %r14,%r15,__LC_SYNC_ENTER_TIMER + l %r15,__LC_KERNEL_STACK +2: ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) + la %r11,STACK_FRAME_OVERHEAD(%r15) + stm %r0,%r7,__PT_R0(%r11) + mvc __PT_R8(32,%r11),__LC_SAVE_AREA_SYNC + stm %r8,%r9,__PT_PSW(%r11) + mvc __PT_INT_CODE(4,%r11),__LC_PGM_ILC + mvc __PT_INT_PARM_LONG(4,%r11),__LC_TRANS_EXC_CODE + tm __LC_PGM_ILC+3,0x80 # check for per exception + jz 0f + l %r1,__TI_task(%r12) + tmh %r8,0x0001 # kernel per event ? + jz pgm_kprobe + oi __TI_flags+3(%r12),_TIF_PER_TRAP + mvc __THREAD_per_address(4,%r1),__LC_PER_ADDRESS + mvc __THREAD_per_cause(2,%r1),__LC_PER_CAUSE + mvc __THREAD_per_paid(1,%r1),__LC_PER_PAID +0: REENABLE_IRQS + xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) + l %r1,BASED(.Ljump_table) + la %r10,0x7f + n %r10,__PT_INT_CODE(%r11) + je sysc_return + sll %r10,2 + l %r1,0(%r10,%r1) # load address of handler routine + lr %r2,%r11 # pass pointer to pt_regs + basr %r14,%r1 # branch to interrupt-handler + j sysc_return + +# +# PER event in supervisor state, must be kprobes +# +pgm_kprobe: + REENABLE_IRQS + xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) + l %r1,BASED(.Ldo_per_trap) + lr %r2,%r11 # pass pointer to pt_regs + basr %r14,%r1 # call do_per_trap + j sysc_return + +# +# single stepped system call +# +pgm_svcper: + oi __TI_flags+3(%r12),_TIF_PER_TRAP + mvc __LC_RETURN_PSW(4),__LC_SVC_NEW_PSW + mvc __LC_RETURN_PSW+4(4),BASED(.Lsysc_per) + lpsw __LC_RETURN_PSW # branch to sysc_per and enable irqs + +/* + * IO interrupt handler routine + */ + +ENTRY(io_int_handler) + stck __LC_INT_CLOCK + stpt __LC_ASYNC_ENTER_TIMER + stm %r8,%r15,__LC_SAVE_AREA_ASYNC + l %r12,__LC_THREAD_INFO + l %r13,__LC_SVC_NEW_PSW+4 + lm %r8,%r9,__LC_IO_OLD_PSW + tmh %r8,0x0001 # interrupting from user ? + jz io_skip + UPDATE_VTIME %r14,%r15,__LC_ASYNC_ENTER_TIMER +io_skip: + SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT + stm %r0,%r7,__PT_R0(%r11) + mvc __PT_R8(32,%r11),__LC_SAVE_AREA_ASYNC + stm %r8,%r9,__PT_PSW(%r11) + TRACE_IRQS_OFF + xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) + l %r1,BASED(.Ldo_IRQ) + lr %r2,%r11 # pass pointer to pt_regs + basr %r14,%r1 # call do_IRQ +io_return: + LOCKDEP_SYS_EXIT + TRACE_IRQS_ON +io_tif: + tm __TI_flags+3(%r12),_TIF_WORK_INT + jnz io_work # there is work to do (signals etc.) +io_restore: + mvc __LC_RETURN_PSW(8),__PT_PSW(%r11) + stpt __LC_EXIT_TIMER + lm %r0,%r15,__PT_R0(%r11) + lpsw __LC_RETURN_PSW +io_done: + +# +# There is work todo, find out in which context we have been interrupted: +# 1) if we return to user space we can do all _TIF_WORK_INT work +# 2) if we return to kernel code and preemptive scheduling is enabled check +# the preemption counter and if it is zero call preempt_schedule_irq +# Before any work can be done, a switch to the kernel stack is required. +# +io_work: + tm __PT_PSW+1(%r11),0x01 # returning to user ? + jo io_work_user # yes -> do resched & signal +#ifdef CONFIG_PREEMPT + # check for preemptive scheduling + icm %r0,15,__TI_precount(%r12) + jnz io_restore # preemption disabled + tm __TI_flags+3(%r12),_TIF_NEED_RESCHED + jno io_restore + # switch to kernel stack + l %r1,__PT_R15(%r11) + ahi %r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE) + mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11) + xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) + la %r11,STACK_FRAME_OVERHEAD(%r1) + lr %r15,%r1 + # TRACE_IRQS_ON already done at io_return, call + # TRACE_IRQS_OFF to keep things symmetrical + TRACE_IRQS_OFF + l %r1,BASED(.Lpreempt_irq) + basr %r14,%r1 # call preempt_schedule_irq + j io_return +#else + j io_restore +#endif + +# +# Need to do work before returning to userspace, switch to kernel stack +# +io_work_user: + l %r1,__LC_KERNEL_STACK + ahi %r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE) + mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11) + xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) + la %r11,STACK_FRAME_OVERHEAD(%r1) + lr %r15,%r1 + +# +# One of the work bits is on. Find out which one. +# Checked are: _TIF_SIGPENDING, _TIF_NOTIFY_RESUME, _TIF_NEED_RESCHED +# and _TIF_MCCK_PENDING +# +io_work_tif: + tm __TI_flags+3(%r12),_TIF_MCCK_PENDING + jo io_mcck_pending + tm __TI_flags+3(%r12),_TIF_NEED_RESCHED + jo io_reschedule + tm __TI_flags+3(%r12),_TIF_SIGPENDING + jo io_sigpending + tm __TI_flags+3(%r12),_TIF_NOTIFY_RESUME + jo io_notify_resume + j io_return # beware of critical section cleanup + +# +# _TIF_MCCK_PENDING is set, call handler +# +io_mcck_pending: + # TRACE_IRQS_ON already done at io_return + l %r1,BASED(.Lhandle_mcck) + basr %r14,%r1 # TIF bit will be cleared by handler + TRACE_IRQS_OFF + j io_return + +# +# _TIF_NEED_RESCHED is set, call schedule +# +io_reschedule: + # TRACE_IRQS_ON already done at io_return + l %r1,BASED(.Lschedule) + ssm __LC_SVC_NEW_PSW # reenable interrupts + basr %r14,%r1 # call scheduler + ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts + TRACE_IRQS_OFF + j io_return + +# +# _TIF_SIGPENDING is set, call do_signal +# +io_sigpending: + # TRACE_IRQS_ON already done at io_return + l %r1,BASED(.Ldo_signal) + ssm __LC_SVC_NEW_PSW # reenable interrupts + lr %r2,%r11 # pass pointer to pt_regs + basr %r14,%r1 # call do_signal + ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts + TRACE_IRQS_OFF + j io_return + +# +# _TIF_SIGPENDING is set, call do_signal +# +io_notify_resume: + # TRACE_IRQS_ON already done at io_return + l %r1,BASED(.Ldo_notify_resume) + ssm __LC_SVC_NEW_PSW # reenable interrupts + lr %r2,%r11 # pass pointer to pt_regs + basr %r14,%r1 # call do_notify_resume + ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts + TRACE_IRQS_OFF + j io_return + +/* + * External interrupt handler routine + */ + +ENTRY(ext_int_handler) + stck __LC_INT_CLOCK + stpt __LC_ASYNC_ENTER_TIMER + stm %r8,%r15,__LC_SAVE_AREA_ASYNC + l %r12,__LC_THREAD_INFO + l %r13,__LC_SVC_NEW_PSW+4 + lm %r8,%r9,__LC_EXT_OLD_PSW + tmh %r8,0x0001 # interrupting from user ? + jz ext_skip + UPDATE_VTIME %r14,%r15,__LC_ASYNC_ENTER_TIMER +ext_skip: + SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT + stm %r0,%r7,__PT_R0(%r11) + mvc __PT_R8(32,%r11),__LC_SAVE_AREA_ASYNC + stm %r8,%r9,__PT_PSW(%r11) + TRACE_IRQS_OFF + lr %r2,%r11 # pass pointer to pt_regs + l %r3,__LC_EXT_CPU_ADDR # get cpu address + interruption code + l %r4,__LC_EXT_PARAMS # get external parameters + l %r1,BASED(.Ldo_extint) + basr %r14,%r1 # call do_extint + j io_return + +/* + * Load idle PSW. The second "half" of this function is in cleanup_idle. + */ +ENTRY(psw_idle) + st %r4,__SF_EMPTY(%r15) + basr %r1,0 + la %r1,psw_idle_lpsw+4-.(%r1) + st %r1,__SF_EMPTY+4(%r15) + oi __SF_EMPTY+4(%r15),0x80 + la %r1,.Lvtimer_max-psw_idle_lpsw-4(%r1) + stck __IDLE_ENTER(%r2) + ltr %r5,%r5 + stpt __VQ_IDLE_ENTER(%r3) + jz psw_idle_lpsw + spt 0(%r1) +psw_idle_lpsw: + lpsw __SF_EMPTY(%r15) + br %r14 +psw_idle_end: + +__critical_end: + +/* + * Machine check handler routines + */ + +ENTRY(mcck_int_handler) + stck __LC_MCCK_CLOCK + spt __LC_CPU_TIMER_SAVE_AREA # revalidate cpu timer + lm %r0,%r15,__LC_GPREGS_SAVE_AREA # revalidate gprs + l %r12,__LC_THREAD_INFO + l %r13,__LC_SVC_NEW_PSW+4 + lm %r8,%r9,__LC_MCK_OLD_PSW + tm __LC_MCCK_CODE,0x80 # system damage? + jo mcck_panic # yes -> rest of mcck code invalid + la %r14,__LC_CPU_TIMER_SAVE_AREA + mvc __LC_MCCK_ENTER_TIMER(8),0(%r14) + tm __LC_MCCK_CODE+5,0x02 # stored cpu timer value valid? + jo 3f + la %r14,__LC_SYNC_ENTER_TIMER + clc 0(8,%r14),__LC_ASYNC_ENTER_TIMER + jl 0f + la %r14,__LC_ASYNC_ENTER_TIMER +0: clc 0(8,%r14),__LC_EXIT_TIMER + jl 1f + la %r14,__LC_EXIT_TIMER +1: clc 0(8,%r14),__LC_LAST_UPDATE_TIMER + jl 2f + la %r14,__LC_LAST_UPDATE_TIMER +2: spt 0(%r14) + mvc __LC_MCCK_ENTER_TIMER(8),0(%r14) +3: tm __LC_MCCK_CODE+2,0x09 # mwp + ia of old psw valid? + jno mcck_panic # no -> skip cleanup critical + tm %r8,0x0001 # interrupting from user ? + jz mcck_skip + UPDATE_VTIME %r14,%r15,__LC_MCCK_ENTER_TIMER +mcck_skip: + SWITCH_ASYNC __LC_GPREGS_SAVE_AREA+32,__LC_PANIC_STACK,PAGE_SHIFT + mvc __PT_R0(64,%r11),__LC_GPREGS_SAVE_AREA + stm %r8,%r9,__PT_PSW(%r11) + xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) + l %r1,BASED(.Ldo_machine_check) + lr %r2,%r11 # pass pointer to pt_regs + basr %r14,%r1 # call s390_do_machine_check + tm __PT_PSW+1(%r11),0x01 # returning to user ? + jno mcck_return + l %r1,__LC_KERNEL_STACK # switch to kernel stack + ahi %r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE) + mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11) + xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) + la %r11,STACK_FRAME_OVERHEAD(%r15) + lr %r15,%r1 + ssm __LC_PGM_NEW_PSW # turn dat on, keep irqs off + tm __TI_flags+3(%r12),_TIF_MCCK_PENDING + jno mcck_return + TRACE_IRQS_OFF + l %r1,BASED(.Lhandle_mcck) + basr %r14,%r1 # call s390_handle_mcck + TRACE_IRQS_ON +mcck_return: + mvc __LC_RETURN_MCCK_PSW(8),__PT_PSW(%r11) # move return PSW + tm __LC_RETURN_MCCK_PSW+1,0x01 # returning to user ? + jno 0f + lm %r0,%r15,__PT_R0(%r11) + stpt __LC_EXIT_TIMER + lpsw __LC_RETURN_MCCK_PSW +0: lm %r0,%r15,__PT_R0(%r11) + lpsw __LC_RETURN_MCCK_PSW + +mcck_panic: + l %r14,__LC_PANIC_STACK + slr %r14,%r15 + sra %r14,PAGE_SHIFT + jz 0f + l %r15,__LC_PANIC_STACK +0: ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) + j mcck_skip + +# +# PSW restart interrupt handler +# +ENTRY(restart_int_handler) + st %r15,__LC_SAVE_AREA_RESTART + l %r15,__LC_RESTART_STACK + ahi %r15,-__PT_SIZE # create pt_regs on stack + xc 0(__PT_SIZE,%r15),0(%r15) + stm %r0,%r14,__PT_R0(%r15) + mvc __PT_R15(4,%r15),__LC_SAVE_AREA_RESTART + mvc __PT_PSW(8,%r15),__LC_RST_OLD_PSW # store restart old psw + ahi %r15,-STACK_FRAME_OVERHEAD # create stack frame on stack + xc 0(STACK_FRAME_OVERHEAD,%r15),0(%r15) + lm %r1,%r3,__LC_RESTART_FN # load fn, parm & source cpu + ltr %r3,%r3 # test source cpu address + jm 1f # negative -> skip source stop +0: sigp %r4,%r3,1 # sigp sense to source cpu + brc 10,0b # wait for status stored +1: basr %r14,%r1 # call function + stap __SF_EMPTY(%r15) # store cpu address + lh %r3,__SF_EMPTY(%r15) +2: sigp %r4,%r3,5 # sigp stop to current cpu + brc 2,2b +3: j 3b + + .section .kprobes.text, "ax" + +#ifdef CONFIG_CHECK_STACK +/* + * The synchronous or the asynchronous stack overflowed. We are dead. + * No need to properly save the registers, we are going to panic anyway. + * Setup a pt_regs so that show_trace can provide a good call trace. + */ +stack_overflow: + l %r15,__LC_PANIC_STACK # change to panic stack + ahi %r15,-__PT_SIZE # create pt_regs + stm %r0,%r7,__PT_R0(%r15) + stm %r8,%r9,__PT_PSW(%r15) + mvc __PT_R8(32,%r11),0(%r14) + lr %r15,%r11 + ahi %r15,-STACK_FRAME_OVERHEAD + l %r1,BASED(1f) + xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) + lr %r2,%r11 # pass pointer to pt_regs + br %r1 # branch to kernel_stack_overflow +1: .long kernel_stack_overflow +#endif + +cleanup_table: + .long system_call + 0x80000000 + .long sysc_do_svc + 0x80000000 + .long sysc_tif + 0x80000000 + .long sysc_restore + 0x80000000 + .long sysc_done + 0x80000000 + .long io_tif + 0x80000000 + .long io_restore + 0x80000000 + .long io_done + 0x80000000 + .long psw_idle + 0x80000000 + .long psw_idle_end + 0x80000000 + +cleanup_critical: + cl %r9,BASED(cleanup_table) # system_call + jl 0f + cl %r9,BASED(cleanup_table+4) # sysc_do_svc + jl cleanup_system_call + cl %r9,BASED(cleanup_table+8) # sysc_tif + jl 0f + cl %r9,BASED(cleanup_table+12) # sysc_restore + jl cleanup_sysc_tif + cl %r9,BASED(cleanup_table+16) # sysc_done + jl cleanup_sysc_restore + cl %r9,BASED(cleanup_table+20) # io_tif + jl 0f + cl %r9,BASED(cleanup_table+24) # io_restore + jl cleanup_io_tif + cl %r9,BASED(cleanup_table+28) # io_done + jl cleanup_io_restore + cl %r9,BASED(cleanup_table+32) # psw_idle + jl 0f + cl %r9,BASED(cleanup_table+36) # psw_idle_end + jl cleanup_idle +0: br %r14 + +cleanup_system_call: + # check if stpt has been executed + cl %r9,BASED(cleanup_system_call_insn) + jh 0f + mvc __LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER + chi %r11,__LC_SAVE_AREA_ASYNC + je 0f + mvc __LC_SYNC_ENTER_TIMER(8),__LC_MCCK_ENTER_TIMER +0: # check if stm has been executed + cl %r9,BASED(cleanup_system_call_insn+4) + jh 0f + mvc __LC_SAVE_AREA_SYNC(32),0(%r11) +0: # set up saved registers r12, and r13 + st %r12,16(%r11) # r12 thread-info pointer + st %r13,20(%r11) # r13 literal-pool pointer + # check if the user time calculation has been done + cl %r9,BASED(cleanup_system_call_insn+8) + jh 0f + l %r10,__LC_EXIT_TIMER + l %r15,__LC_EXIT_TIMER+4 + SUB64 %r10,%r15,__LC_SYNC_ENTER_TIMER + ADD64 %r10,%r15,__LC_USER_TIMER + st %r10,__LC_USER_TIMER + st %r15,__LC_USER_TIMER+4 +0: # check if the system time calculation has been done + cl %r9,BASED(cleanup_system_call_insn+12) + jh 0f + l %r10,__LC_LAST_UPDATE_TIMER + l %r15,__LC_LAST_UPDATE_TIMER+4 + SUB64 %r10,%r15,__LC_EXIT_TIMER + ADD64 %r10,%r15,__LC_SYSTEM_TIMER + st %r10,__LC_SYSTEM_TIMER + st %r15,__LC_SYSTEM_TIMER+4 +0: # update accounting time stamp + mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER + # set up saved register 11 + l %r15,__LC_KERNEL_STACK + ahi %r15,-__PT_SIZE + st %r15,12(%r11) # r11 pt_regs pointer + # fill pt_regs + mvc __PT_R8(32,%r15),__LC_SAVE_AREA_SYNC + stm %r0,%r7,__PT_R0(%r15) + mvc __PT_PSW(8,%r15),__LC_SVC_OLD_PSW + mvc __PT_INT_CODE(4,%r15),__LC_SVC_ILC + # setup saved register 15 + ahi %r15,-STACK_FRAME_OVERHEAD + st %r15,28(%r11) # r15 stack pointer + # set new psw address and exit + l %r9,BASED(cleanup_table+4) # sysc_do_svc + 0x80000000 + br %r14 +cleanup_system_call_insn: + .long system_call + 0x80000000 + .long sysc_stm + 0x80000000 + .long sysc_vtime + 0x80000000 + 36 + .long sysc_vtime + 0x80000000 + 76 + +cleanup_sysc_tif: + l %r9,BASED(cleanup_table+8) # sysc_tif + 0x80000000 + br %r14 + +cleanup_sysc_restore: + cl %r9,BASED(cleanup_sysc_restore_insn) + jhe 0f + l %r9,12(%r11) # get saved pointer to pt_regs + mvc __LC_RETURN_PSW(8),__PT_PSW(%r9) + mvc 0(32,%r11),__PT_R8(%r9) + lm %r0,%r7,__PT_R0(%r9) +0: lm %r8,%r9,__LC_RETURN_PSW + br %r14 +cleanup_sysc_restore_insn: + .long sysc_done - 4 + 0x80000000 + +cleanup_io_tif: + l %r9,BASED(cleanup_table+20) # io_tif + 0x80000000 + br %r14 + +cleanup_io_restore: + cl %r9,BASED(cleanup_io_restore_insn) + jhe 0f + l %r9,12(%r11) # get saved r11 pointer to pt_regs + mvc __LC_RETURN_PSW(8),__PT_PSW(%r9) + mvc 0(32,%r11),__PT_R8(%r9) + lm %r0,%r7,__PT_R0(%r9) +0: lm %r8,%r9,__LC_RETURN_PSW + br %r14 +cleanup_io_restore_insn: + .long io_done - 4 + 0x80000000 + +cleanup_idle: + # copy interrupt clock & cpu timer + mvc __IDLE_EXIT(8,%r2),__LC_INT_CLOCK + mvc __VQ_IDLE_EXIT(8,%r3),__LC_ASYNC_ENTER_TIMER + chi %r11,__LC_SAVE_AREA_ASYNC + je 0f + mvc __IDLE_EXIT(8,%r2),__LC_MCCK_CLOCK + mvc __VQ_IDLE_EXIT(8,%r3),__LC_MCCK_ENTER_TIMER +0: # check if stck has been executed + cl %r9,BASED(cleanup_idle_insn) + jhe 1f + mvc __IDLE_ENTER(8,%r2),__IDLE_EXIT(%r2) + mvc __VQ_IDLE_ENTER(8,%r3),__VQ_IDLE_EXIT(%r3) + j 2f +1: # check if the cpu timer has been reprogrammed + ltr %r5,%r5 + jz 2f + spt __VQ_IDLE_ENTER(%r3) +2: # account system time going idle + lm %r9,%r10,__LC_STEAL_TIMER + ADD64 %r9,%r10,__IDLE_ENTER(%r2) + SUB64 %r9,%r10,__LC_LAST_UPDATE_CLOCK + stm %r9,%r10,__LC_STEAL_TIMER + mvc __LC_LAST_UPDATE_CLOCK(8),__IDLE_EXIT(%r2) + lm %r9,%r10,__LC_SYSTEM_TIMER + ADD64 %r9,%r10,__LC_LAST_UPDATE_TIMER + SUB64 %r9,%r10,__VQ_IDLE_ENTER(%r3) + stm %r9,%r10,__LC_SYSTEM_TIMER + mvc __LC_LAST_UPDATE_TIMER(8),__VQ_IDLE_EXIT(%r3) + # prepare return psw + n %r8,BASED(cleanup_idle_wait) # clear wait state bit + l %r9,24(%r11) # return from psw_idle + br %r14 +cleanup_idle_insn: + .long psw_idle_lpsw + 0x80000000 +cleanup_idle_wait: + .long 0xfffdffff + +/* + * Integer constants + */ + .align 4 +.Lnr_syscalls: + .long NR_syscalls +.Lvtimer_max: + .quad 0x7fffffffffffffff + +/* + * Symbol constants + */ +.Ldo_machine_check: .long s390_do_machine_check +.Lhandle_mcck: .long s390_handle_mcck +.Ldo_IRQ: .long do_IRQ +.Ldo_extint: .long do_extint +.Ldo_signal: .long do_signal +.Ldo_notify_resume: .long do_notify_resume +.Ldo_per_trap: .long do_per_trap +.Ldo_execve: .long do_execve +.Lexecve_tail: .long execve_tail +.Ljump_table: .long pgm_check_table +.Lschedule: .long schedule +#ifdef CONFIG_PREEMPT +.Lpreempt_irq: .long preempt_schedule_irq +#endif +.Ltrace_enter: .long do_syscall_trace_enter +.Ltrace_exit: .long do_syscall_trace_exit +.Lschedule_tail: .long schedule_tail +.Lsys_call_table: .long sys_call_table +.Lsysc_per: .long sysc_per + 0x80000000 +#ifdef CONFIG_TRACE_IRQFLAGS +.Lhardirqs_on: .long trace_hardirqs_on_caller +.Lhardirqs_off: .long trace_hardirqs_off_caller +#endif +#ifdef CONFIG_LOCKDEP +.Llockdep_sys_exit: .long lockdep_sys_exit +#endif +.Lcritical_start: .long __critical_start + 0x80000000 +.Lcritical_length: .long __critical_end - __critical_start + + .section .rodata, "a" +#define SYSCALL(esa,esame,emu) .long esa + .globl sys_call_table +sys_call_table: +#include "syscalls.S" +#undef SYSCALL |