| /* |
| * 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) |
| stm %r6,%r15,__SF_GPRS(%r15) # store gprs of prev task |
| st %r15,__THREAD_ksp(%r2) # store kernel stack of prev |
| l %r4,__THREAD_info(%r2) # get thread_info of prev |
| l %r5,__THREAD_info(%r3) # get thread_info of next |
| lr %r15,%r5 |
| ahi %r15,STACK_SIZE # end of kernel stack of next |
| st %r3,__LC_CURRENT # store task struct of next |
| st %r5,__LC_THREAD_INFO # store thread info of next |
| st %r15,__LC_KERNEL_STACK # store end of kernel stack |
| lctl %c4,%c4,__TASK_pid(%r3) # load pid to control reg. 4 |
| mvc __LC_CURRENT_PID(4,%r0),__TASK_pid(%r3) # store pid of next |
| l %r15,__THREAD_ksp(%r3) # load kernel stack 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: lm %r6,%r15,__SF_GPRS(%r15) # load gprs of next task |
| 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 |
