| /* |
| * S390 low-level entry points. |
| * |
| * Copyright 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> |
| #include <asm/sigp.h> |
| |
| __PT_R0 = __PT_GPRS |
| __PT_R1 = __PT_GPRS + 8 |
| __PT_R2 = __PT_GPRS + 16 |
| __PT_R3 = __PT_GPRS + 24 |
| __PT_R4 = __PT_GPRS + 32 |
| __PT_R5 = __PT_GPRS + 40 |
| __PT_R6 = __PT_GPRS + 48 |
| __PT_R7 = __PT_GPRS + 56 |
| __PT_R8 = __PT_GPRS + 64 |
| __PT_R9 = __PT_GPRS + 72 |
| __PT_R10 = __PT_GPRS + 80 |
| __PT_R11 = __PT_GPRS + 88 |
| __PT_R12 = __PT_GPRS + 96 |
| __PT_R13 = __PT_GPRS + 104 |
| __PT_R14 = __PT_GPRS + 112 |
| __PT_R15 = __PT_GPRS + 120 |
| |
| STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER |
| STACK_SIZE = 1 << STACK_SHIFT |
| |
| _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) |
| _TIF_EXIT_SIE = (_TIF_SIGPENDING | _TIF_NEED_RESCHED | _TIF_MCCK_PENDING) |
| |
| #define BASED(name) name-system_call(%r13) |
| |
| .macro TRACE_IRQS_ON |
| #ifdef CONFIG_TRACE_IRQFLAGS |
| basr %r2,%r0 |
| brasl %r14,trace_hardirqs_on_caller |
| #endif |
| .endm |
| |
| .macro TRACE_IRQS_OFF |
| #ifdef CONFIG_TRACE_IRQFLAGS |
| basr %r2,%r0 |
| brasl %r14,trace_hardirqs_off_caller |
| #endif |
| .endm |
| |
| .macro LOCKDEP_SYS_EXIT |
| #ifdef CONFIG_LOCKDEP |
| tm __PT_PSW+1(%r11),0x01 # returning to user ? |
| jz .+10 |
| brasl %r14,lockdep_sys_exit |
| #endif |
| .endm |
| |
| .macro SPP newpp |
| #if defined(CONFIG_KVM) || defined(CONFIG_KVM_MODULE) |
| tm __LC_MACHINE_FLAGS+6,0x20 # MACHINE_FLAG_SPP |
| jz .+8 |
| .insn s,0xb2800000,\newpp |
| #endif |
| .endm |
| |
| .macro HANDLE_SIE_INTERCEPT scratch |
| #if defined(CONFIG_KVM) || defined(CONFIG_KVM_MODULE) |
| tmhh %r8,0x0001 # interrupting from user ? |
| jnz .+42 |
| lgr \scratch,%r9 |
| slg \scratch,BASED(.Lsie_loop) |
| clg \scratch,BASED(.Lsie_length) |
| jhe .+22 |
| lg %r9,BASED(.Lsie_loop) |
| SPP BASED(.Lhost_id) # set host id |
| #endif |
| .endm |
| |
| .macro CHECK_STACK stacksize,savearea |
| #ifdef CONFIG_CHECK_STACK |
| tml %r15,\stacksize - CONFIG_STACK_GUARD |
| lghi %r14,\savearea |
| jz stack_overflow |
| #endif |
| .endm |
| |
| .macro SWITCH_ASYNC savearea,stack,shift |
| tmhh %r8,0x0001 # interrupting from user ? |
| jnz 1f |
| lgr %r14,%r9 |
| slg %r14,BASED(.Lcritical_start) |
| clg %r14,BASED(.Lcritical_length) |
| jhe 0f |
| lghi %r11,\savearea # inside critical section, do cleanup |
| brasl %r14,cleanup_critical |
| tmhh %r8,0x0001 # retest problem state after cleanup |
| jnz 1f |
| 0: lg %r14,\stack # are we already on the target stack? |
| slgr %r14,%r15 |
| srag %r14,%r14,\shift |
| jnz 1f |
| CHECK_STACK 1<<\shift,\savearea |
| j 2f |
| 1: lg %r15,\stack # load target stack |
| 2: aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) |
| la %r11,STACK_FRAME_OVERHEAD(%r15) |
| .endm |
| |
| .macro UPDATE_VTIME scratch,enter_timer |
| lg \scratch,__LC_EXIT_TIMER |
| slg \scratch,\enter_timer |
| alg \scratch,__LC_USER_TIMER |
| stg \scratch,__LC_USER_TIMER |
| lg \scratch,__LC_LAST_UPDATE_TIMER |
| slg \scratch,__LC_EXIT_TIMER |
| alg \scratch,__LC_SYSTEM_TIMER |
| stg \scratch,__LC_SYSTEM_TIMER |
| mvc __LC_LAST_UPDATE_TIMER(8),\enter_timer |
| .endm |
| |
| .macro LAST_BREAK scratch |
| srag \scratch,%r10,23 |
| jz .+10 |
| stg %r10,__TI_last_break(%r12) |
| .endm |
| |
| .macro REENABLE_IRQS |
| stg %r8,__LC_RETURN_PSW |
| ni __LC_RETURN_PSW,0xbf |
| ssm __LC_RETURN_PSW |
| .endm |
| |
| .macro STCK savearea |
| #ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES |
| .insn s,0xb27c0000,\savearea # store clock fast |
| #else |
| .insn s,0xb2050000,\savearea # store clock |
| #endif |
| .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) |
| stmg %r6,%r15,__SF_GPRS(%r15) # store gprs of prev task |
| stg %r15,__THREAD_ksp(%r2) # store kernel stack of prev |
| lg %r4,__THREAD_info(%r2) # get thread_info of prev |
| lg %r5,__THREAD_info(%r3) # get thread_info of next |
| lgr %r15,%r5 |
| aghi %r15,STACK_SIZE # end of kernel stack of next |
| stg %r3,__LC_CURRENT # store task struct of next |
| stg %r5,__LC_THREAD_INFO # store thread info of next |
| stg %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(4,%r0),__TASK_pid(%r3) # store pid of next |
| lg %r15,__THREAD_ksp(%r3) # load kernel stack of next |
| tm __TI_flags+7(%r4),_TIF_MCCK_PENDING # machine check pending? |
| jz 0f |
| ni __TI_flags+7(%r4),255-_TIF_MCCK_PENDING # clear flag in prev |
| oi __TI_flags+7(%r5),_TIF_MCCK_PENDING # set it in next |
| 0: lmg %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_stmg: |
| stmg %r8,%r15,__LC_SAVE_AREA_SYNC |
| lg %r10,__LC_LAST_BREAK |
| lg %r12,__LC_THREAD_INFO |
| larl %r13,system_call |
| sysc_per: |
| lg %r15,__LC_KERNEL_STACK |
| aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) |
| la %r11,STACK_FRAME_OVERHEAD(%r15) # pointer to pt_regs |
| sysc_vtime: |
| UPDATE_VTIME %r13,__LC_SYNC_ENTER_TIMER |
| LAST_BREAK %r13 |
| stmg %r0,%r7,__PT_R0(%r11) |
| mvc __PT_R8(64,%r11),__LC_SAVE_AREA_SYNC |
| mvc __PT_PSW(16,%r11),__LC_SVC_OLD_PSW |
| mvc __PT_INT_CODE(4,%r11),__LC_SVC_ILC |
| sysc_do_svc: |
| oi __TI_flags+7(%r12),_TIF_SYSCALL |
| llgh %r8,__PT_INT_CODE+2(%r11) |
| slag %r8,%r8,2 # shift and test for svc 0 |
| jnz sysc_nr_ok |
| # svc 0: system call number in %r1 |
| llgfr %r1,%r1 # clear high word in r1 |
| cghi %r1,NR_syscalls |
| jnl sysc_nr_ok |
| sth %r1,__PT_INT_CODE+2(%r11) |
| slag %r8,%r1,2 |
| sysc_nr_ok: |
| larl %r10,sys_call_table # 64 bit system call table |
| #ifdef CONFIG_COMPAT |
| tm __TI_flags+5(%r12),(_TIF_31BIT>>16) |
| jno sysc_noemu |
| larl %r10,sys_call_table_emu # 31 bit system call table |
| sysc_noemu: |
| #endif |
| xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) |
| stg %r2,__PT_ORIG_GPR2(%r11) |
| stg %r7,STACK_FRAME_OVERHEAD(%r15) |
| lgf %r9,0(%r8,%r10) # get system call add. |
| tm __TI_flags+6(%r12),_TIF_TRACE >> 8 |
| jnz sysc_tracesys |
| basr %r14,%r9 # call sys_xxxx |
| stg %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+7(%r12),_TIF_WORK_SVC |
| jnz sysc_work # check for work |
| ni __TI_flags+7(%r12),255-_TIF_SYSCALL |
| sysc_restore: |
| lg %r14,__LC_VDSO_PER_CPU |
| lmg %r0,%r10,__PT_R0(%r11) |
| mvc __LC_RETURN_PSW(16),__PT_PSW(%r11) |
| stpt __LC_EXIT_TIMER |
| mvc __VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER |
| lmg %r11,%r15,__PT_R11(%r11) |
| lpswe __LC_RETURN_PSW |
| sysc_done: |
| |
| # |
| # One of the work bits is on. Find out which one. |
| # |
| sysc_work: |
| tm __TI_flags+7(%r12),_TIF_MCCK_PENDING |
| jo sysc_mcck_pending |
| tm __TI_flags+7(%r12),_TIF_NEED_RESCHED |
| jo sysc_reschedule |
| tm __TI_flags+7(%r12),_TIF_SIGPENDING |
| jo sysc_sigpending |
| tm __TI_flags+7(%r12),_TIF_NOTIFY_RESUME |
| jo sysc_notify_resume |
| tm __TI_flags+7(%r12),_TIF_PER_TRAP |
| jo sysc_singlestep |
| j sysc_return # beware of critical section cleanup |
| |
| # |
| # _TIF_NEED_RESCHED is set, call schedule |
| # |
| sysc_reschedule: |
| larl %r14,sysc_return |
| jg schedule |
| |
| # |
| # _TIF_MCCK_PENDING is set, call handler |
| # |
| sysc_mcck_pending: |
| larl %r14,sysc_return |
| jg s390_handle_mcck # TIF bit will be cleared by handler |
| |
| # |
| # _TIF_SIGPENDING is set, call do_signal |
| # |
| sysc_sigpending: |
| ni __TI_flags+7(%r12),255-_TIF_PER_TRAP # clear TIF_PER_TRAP |
| lgr %r2,%r11 # pass pointer to pt_regs |
| brasl %r14,do_signal |
| tm __TI_flags+7(%r12),_TIF_SYSCALL |
| jno sysc_return |
| lmg %r2,%r7,__PT_R2(%r11) # load svc arguments |
| lghi %r8,0 # svc 0 returns -ENOSYS |
| lh %r1,__PT_INT_CODE+2(%r11) # load new svc number |
| cghi %r1,NR_syscalls |
| jnl sysc_nr_ok # invalid svc number -> do svc 0 |
| slag %r8,%r1,2 |
| j sysc_nr_ok # restart svc |
| |
| # |
| # _TIF_NOTIFY_RESUME is set, call do_notify_resume |
| # |
| sysc_notify_resume: |
| lgr %r2,%r11 # pass pointer to pt_regs |
| larl %r14,sysc_return |
| jg do_notify_resume |
| |
| # |
| # _TIF_PER_TRAP is set, call do_per_trap |
| # |
| sysc_singlestep: |
| ni __TI_flags+7(%r12),255-(_TIF_SYSCALL | _TIF_PER_TRAP) |
| lgr %r2,%r11 # pass pointer to pt_regs |
| larl %r14,sysc_return |
| jg do_per_trap |
| |
| # |
| # call tracehook_report_syscall_entry/tracehook_report_syscall_exit before |
| # and after the system call |
| # |
| sysc_tracesys: |
| lgr %r2,%r11 # pass pointer to pt_regs |
| la %r3,0 |
| llgh %r0,__PT_INT_CODE+2(%r11) |
| stg %r0,__PT_R2(%r11) |
| brasl %r14,do_syscall_trace_enter |
| lghi %r0,NR_syscalls |
| clgr %r0,%r2 |
| jnh sysc_tracenogo |
| sllg %r8,%r2,2 |
| lgf %r9,0(%r8,%r10) |
| sysc_tracego: |
| lmg %r3,%r7,__PT_R3(%r11) |
| stg %r7,STACK_FRAME_OVERHEAD(%r15) |
| lg %r2,__PT_ORIG_GPR2(%r11) |
| basr %r14,%r9 # call sys_xxx |
| stg %r2,__PT_R2(%r11) # store return value |
| sysc_tracenogo: |
| tm __TI_flags+6(%r12),_TIF_TRACE >> 8 |
| jz sysc_return |
| lgr %r2,%r11 # pass pointer to pt_regs |
| larl %r14,sysc_return |
| jg do_syscall_trace_exit |
| |
| # |
| # a new process exits the kernel with ret_from_fork |
| # |
| ENTRY(ret_from_fork) |
| la %r11,STACK_FRAME_OVERHEAD(%r15) |
| lg %r12,__LC_THREAD_INFO |
| tm __PT_PSW+1(%r11),0x01 # forking a kernel thread ? |
| jo 0f |
| stg %r15,__PT_R15(%r11) # store stack pointer for new kthread |
| 0: brasl %r14,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) |
| stmg %r12,%r15,96(%r15) |
| lgr %r14,%r15 |
| aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) |
| stg %r14,__SF_BACKCHAIN(%r15) |
| la %r12,STACK_FRAME_OVERHEAD(%r15) |
| xc 0(__PT_SIZE,%r12),0(%r12) |
| lgr %r5,%r12 |
| brasl %r14,do_execve |
| ltgfr %r2,%r2 |
| je 0f |
| aghi %r15,(STACK_FRAME_OVERHEAD + __PT_SIZE) |
| lmg %r12,%r15,96(%r15) |
| br %r14 |
| # execve succeeded. |
| 0: ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts |
| lg %r15,__LC_KERNEL_STACK # load ksp |
| aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) |
| la %r11,STACK_FRAME_OVERHEAD(%r15) |
| mvc 0(__PT_SIZE,%r11),0(%r12) # copy pt_regs |
| lg %r12,__LC_THREAD_INFO |
| xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) |
| ssm __LC_SVC_NEW_PSW # reenable interrupts |
| brasl %r14,execve_tail |
| j sysc_return |
| |
| /* |
| * Program check handler routine |
| */ |
| |
| ENTRY(pgm_check_handler) |
| stpt __LC_SYNC_ENTER_TIMER |
| stmg %r8,%r15,__LC_SAVE_AREA_SYNC |
| lg %r10,__LC_LAST_BREAK |
| lg %r12,__LC_THREAD_INFO |
| larl %r13,system_call |
| lmg %r8,%r9,__LC_PGM_OLD_PSW |
| HANDLE_SIE_INTERCEPT %r14 |
| tmhh %r8,0x0001 # test problem state bit |
| jnz 1f # -> fault in user space |
| tmhh %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,__LC_SYNC_ENTER_TIMER |
| LAST_BREAK %r14 |
| lg %r15,__LC_KERNEL_STACK |
| 2: aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) |
| la %r11,STACK_FRAME_OVERHEAD(%r15) |
| stmg %r0,%r7,__PT_R0(%r11) |
| mvc __PT_R8(64,%r11),__LC_SAVE_AREA_SYNC |
| stmg %r8,%r9,__PT_PSW(%r11) |
| mvc __PT_INT_CODE(4,%r11),__LC_PGM_ILC |
| mvc __PT_INT_PARM_LONG(8,%r11),__LC_TRANS_EXC_CODE |
| stg %r10,__PT_ARGS(%r11) |
| tm __LC_PGM_ILC+3,0x80 # check for per exception |
| jz 0f |
| lg %r1,__TI_task(%r12) |
| tmhh %r8,0x0001 # kernel per event ? |
| jz pgm_kprobe |
| oi __TI_flags+7(%r12),_TIF_PER_TRAP |
| mvc __THREAD_per_address(8,%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(8,%r15),__SF_BACKCHAIN(%r15) |
| larl %r1,pgm_check_table |
| llgh %r10,__PT_INT_CODE+2(%r11) |
| nill %r10,0x007f |
| sll %r10,3 |
| je sysc_return |
| lg %r1,0(%r10,%r1) # load address of handler routine |
| lgr %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(8,%r15),__SF_BACKCHAIN(%r15) |
| lgr %r2,%r11 # pass pointer to pt_regs |
| brasl %r14,do_per_trap |
| j sysc_return |
| |
| # |
| # single stepped system call |
| # |
| pgm_svcper: |
| oi __TI_flags+7(%r12),_TIF_PER_TRAP |
| mvc __LC_RETURN_PSW(8),__LC_SVC_NEW_PSW |
| larl %r14,sysc_per |
| stg %r14,__LC_RETURN_PSW+8 |
| lpswe __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 |
| stmg %r8,%r15,__LC_SAVE_AREA_ASYNC |
| lg %r10,__LC_LAST_BREAK |
| lg %r12,__LC_THREAD_INFO |
| larl %r13,system_call |
| lmg %r8,%r9,__LC_IO_OLD_PSW |
| HANDLE_SIE_INTERCEPT %r14 |
| SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT |
| tmhh %r8,0x0001 # interrupting from user? |
| jz io_skip |
| UPDATE_VTIME %r14,__LC_ASYNC_ENTER_TIMER |
| LAST_BREAK %r14 |
| io_skip: |
| stmg %r0,%r7,__PT_R0(%r11) |
| mvc __PT_R8(64,%r11),__LC_SAVE_AREA_ASYNC |
| stmg %r8,%r9,__PT_PSW(%r11) |
| TRACE_IRQS_OFF |
| xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) |
| lgr %r2,%r11 # pass pointer to pt_regs |
| brasl %r14,do_IRQ |
| io_return: |
| LOCKDEP_SYS_EXIT |
| TRACE_IRQS_ON |
| io_tif: |
| tm __TI_flags+7(%r12),_TIF_WORK_INT |
| jnz io_work # there is work to do (signals etc.) |
| io_restore: |
| lg %r14,__LC_VDSO_PER_CPU |
| lmg %r0,%r10,__PT_R0(%r11) |
| mvc __LC_RETURN_PSW(16),__PT_PSW(%r11) |
| stpt __LC_EXIT_TIMER |
| mvc __VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER |
| lmg %r11,%r15,__PT_R11(%r11) |
| lpswe __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 kvm is enabled check if we need to |
| # modify the psw to leave SIE |
| # 3) 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 is disabled |
| tm __TI_flags+7(%r12),_TIF_NEED_RESCHED |
| jno io_restore |
| # switch to kernel stack |
| lg %r1,__PT_R15(%r11) |
| aghi %r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE) |
| mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11) |
| xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1) |
| la %r11,STACK_FRAME_OVERHEAD(%r1) |
| lgr %r15,%r1 |
| # TRACE_IRQS_ON already done at io_return, call |
| # TRACE_IRQS_OFF to keep things symmetrical |
| TRACE_IRQS_OFF |
| brasl %r14,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: |
| lg %r1,__LC_KERNEL_STACK |
| aghi %r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE) |
| mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11) |
| xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1) |
| la %r11,STACK_FRAME_OVERHEAD(%r1) |
| lgr %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+7(%r12),_TIF_MCCK_PENDING |
| jo io_mcck_pending |
| tm __TI_flags+7(%r12),_TIF_NEED_RESCHED |
| jo io_reschedule |
| tm __TI_flags+7(%r12),_TIF_SIGPENDING |
| jo io_sigpending |
| tm __TI_flags+7(%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 |
| brasl %r14,s390_handle_mcck # 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 |
| ssm __LC_SVC_NEW_PSW # reenable interrupts |
| brasl %r14,schedule # call scheduler |
| ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts |
| TRACE_IRQS_OFF |
| j io_return |
| |
| # |
| # _TIF_SIGPENDING or is set, call do_signal |
| # |
| io_sigpending: |
| # TRACE_IRQS_ON already done at io_return |
| ssm __LC_SVC_NEW_PSW # reenable interrupts |
| lgr %r2,%r11 # pass pointer to pt_regs |
| brasl %r14,do_signal |
| ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts |
| TRACE_IRQS_OFF |
| j io_return |
| |
| # |
| # _TIF_NOTIFY_RESUME or is set, call do_notify_resume |
| # |
| io_notify_resume: |
| # TRACE_IRQS_ON already done at io_return |
| ssm __LC_SVC_NEW_PSW # reenable interrupts |
| lgr %r2,%r11 # pass pointer to pt_regs |
| brasl %r14,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 |
| stmg %r8,%r15,__LC_SAVE_AREA_ASYNC |
| lg %r10,__LC_LAST_BREAK |
| lg %r12,__LC_THREAD_INFO |
| larl %r13,system_call |
| lmg %r8,%r9,__LC_EXT_OLD_PSW |
| HANDLE_SIE_INTERCEPT %r14 |
| SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT |
| tmhh %r8,0x0001 # interrupting from user ? |
| jz ext_skip |
| UPDATE_VTIME %r14,__LC_ASYNC_ENTER_TIMER |
| LAST_BREAK %r14 |
| ext_skip: |
| stmg %r0,%r7,__PT_R0(%r11) |
| mvc __PT_R8(64,%r11),__LC_SAVE_AREA_ASYNC |
| stmg %r8,%r9,__PT_PSW(%r11) |
| TRACE_IRQS_OFF |
| xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) |
| lghi %r1,4096 |
| lgr %r2,%r11 # pass pointer to pt_regs |
| llgf %r3,__LC_EXT_CPU_ADDR # get cpu address + interruption code |
| llgf %r4,__LC_EXT_PARAMS # get external parameter |
| lg %r5,__LC_EXT_PARAMS2-4096(%r1) # get 64 bit external parameter |
| brasl %r14,do_extint |
| j io_return |
| |
| /* |
| * Load idle PSW. The second "half" of this function is in cleanup_idle. |
| */ |
| ENTRY(psw_idle) |
| stg %r3,__SF_EMPTY(%r15) |
| larl %r1,psw_idle_lpsw+4 |
| stg %r1,__SF_EMPTY+8(%r15) |
| STCK __CLOCK_IDLE_ENTER(%r2) |
| stpt __TIMER_IDLE_ENTER(%r2) |
| psw_idle_lpsw: |
| lpswe __SF_EMPTY(%r15) |
| br %r14 |
| psw_idle_end: |
| |
| __critical_end: |
| |
| /* |
| * Machine check handler routines |
| */ |
| ENTRY(mcck_int_handler) |
| STCK __LC_MCCK_CLOCK |
| la %r1,4095 # revalidate r1 |
| spt __LC_CPU_TIMER_SAVE_AREA-4095(%r1) # revalidate cpu timer |
| lmg %r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r1)# revalidate gprs |
| lg %r10,__LC_LAST_BREAK |
| lg %r12,__LC_THREAD_INFO |
| larl %r13,system_call |
| lmg %r8,%r9,__LC_MCK_OLD_PSW |
| HANDLE_SIE_INTERCEPT %r14 |
| tm __LC_MCCK_CODE,0x80 # system damage? |
| jo mcck_panic # yes -> rest of mcck code invalid |
| lghi %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 |
| SWITCH_ASYNC __LC_GPREGS_SAVE_AREA+64,__LC_PANIC_STACK,PAGE_SHIFT |
| tm %r8,0x0001 # interrupting from user ? |
| jz mcck_skip |
| UPDATE_VTIME %r14,__LC_MCCK_ENTER_TIMER |
| LAST_BREAK %r14 |
| mcck_skip: |
| lghi %r14,__LC_GPREGS_SAVE_AREA |
| mvc __PT_R0(128,%r11),0(%r14) |
| stmg %r8,%r9,__PT_PSW(%r11) |
| xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) |
| lgr %r2,%r11 # pass pointer to pt_regs |
| brasl %r14,s390_do_machine_check |
| tm __PT_PSW+1(%r11),0x01 # returning to user ? |
| jno mcck_return |
| lg %r1,__LC_KERNEL_STACK # switch to kernel stack |
| aghi %r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE) |
| mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11) |
| xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1) |
| la %r11,STACK_FRAME_OVERHEAD(%r1) |
| lgr %r15,%r1 |
| ssm __LC_PGM_NEW_PSW # turn dat on, keep irqs off |
| tm __TI_flags+7(%r12),_TIF_MCCK_PENDING |
| jno mcck_return |
| TRACE_IRQS_OFF |
| brasl %r14,s390_handle_mcck |
| TRACE_IRQS_ON |
| mcck_return: |
| lg %r14,__LC_VDSO_PER_CPU |
| lmg %r0,%r10,__PT_R0(%r11) |
| mvc __LC_RETURN_MCCK_PSW(16),__PT_PSW(%r11) # move return PSW |
| tm __LC_RETURN_MCCK_PSW+1,0x01 # returning to user ? |
| jno 0f |
| stpt __LC_EXIT_TIMER |
| mvc __VDSO_ECTG_BASE(16,%r14),__LC_EXIT_TIMER |
| 0: lmg %r11,%r15,__PT_R11(%r11) |
| lpswe __LC_RETURN_MCCK_PSW |
| |
| mcck_panic: |
| lg %r14,__LC_PANIC_STACK |
| slgr %r14,%r15 |
| srag %r14,%r14,PAGE_SHIFT |
| jz 0f |
| lg %r15,__LC_PANIC_STACK |
| 0: aghi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE) |
| j mcck_skip |
| |
| # |
| # PSW restart interrupt handler |
| # |
| ENTRY(restart_int_handler) |
| stg %r15,__LC_SAVE_AREA_RESTART |
| lg %r15,__LC_RESTART_STACK |
| aghi %r15,-__PT_SIZE # create pt_regs on stack |
| xc 0(__PT_SIZE,%r15),0(%r15) |
| stmg %r0,%r14,__PT_R0(%r15) |
| mvc __PT_R15(8,%r15),__LC_SAVE_AREA_RESTART |
| mvc __PT_PSW(16,%r15),__LC_RST_OLD_PSW # store restart old psw |
| aghi %r15,-STACK_FRAME_OVERHEAD # create stack frame on stack |
| xc 0(STACK_FRAME_OVERHEAD,%r15),0(%r15) |
| lg %r1,__LC_RESTART_FN # load fn, parm & source cpu |
| lg %r2,__LC_RESTART_DATA |
| lg %r3,__LC_RESTART_SOURCE |
| ltgr %r3,%r3 # test source cpu address |
| jm 1f # negative -> skip source stop |
| 0: sigp %r4,%r3,SIGP_SENSE # 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 |
| llgh %r3,__SF_EMPTY(%r15) |
| 2: sigp %r4,%r3,SIGP_STOP # 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: |
| lg %r11,__LC_PANIC_STACK # change to panic stack |
| aghi %r11,-__PT_SIZE # create pt_regs |
| stmg %r0,%r7,__PT_R0(%r11) |
| stmg %r8,%r9,__PT_PSW(%r11) |
| mvc __PT_R8(64,%r11),0(%r14) |
| stg %r10,__PT_ORIG_GPR2(%r11) # store last break to orig_gpr2 |
| lgr %r15,%r11 |
| aghi %r15,-STACK_FRAME_OVERHEAD |
| xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) |
| lgr %r2,%r11 # pass pointer to pt_regs |
| jg kernel_stack_overflow |
| #endif |
| |
| .align 8 |
| cleanup_table: |
| .quad system_call |
| .quad sysc_do_svc |
| .quad sysc_tif |
| .quad sysc_restore |
| .quad sysc_done |
| .quad io_tif |
| .quad io_restore |
| .quad io_done |
| .quad psw_idle |
| .quad psw_idle_end |
| |
| cleanup_critical: |
| clg %r9,BASED(cleanup_table) # system_call |
| jl 0f |
| clg %r9,BASED(cleanup_table+8) # sysc_do_svc |
| jl cleanup_system_call |
| clg %r9,BASED(cleanup_table+16) # sysc_tif |
| jl 0f |
| clg %r9,BASED(cleanup_table+24) # sysc_restore |
| jl cleanup_sysc_tif |
| clg %r9,BASED(cleanup_table+32) # sysc_done |
| jl cleanup_sysc_restore |
| clg %r9,BASED(cleanup_table+40) # io_tif |
| jl 0f |
| clg %r9,BASED(cleanup_table+48) # io_restore |
| jl cleanup_io_tif |
| clg %r9,BASED(cleanup_table+56) # io_done |
| jl cleanup_io_restore |
| clg %r9,BASED(cleanup_table+64) # psw_idle |
| jl 0f |
| clg %r9,BASED(cleanup_table+72) # psw_idle_end |
| jl cleanup_idle |
| 0: br %r14 |
| |
| |
| cleanup_system_call: |
| # check if stpt has been executed |
| clg %r9,BASED(cleanup_system_call_insn) |
| jh 0f |
| mvc __LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER |
| cghi %r11,__LC_SAVE_AREA_ASYNC |
| je 0f |
| mvc __LC_SYNC_ENTER_TIMER(8),__LC_MCCK_ENTER_TIMER |
| 0: # check if stmg has been executed |
| clg %r9,BASED(cleanup_system_call_insn+8) |
| jh 0f |
| mvc __LC_SAVE_AREA_SYNC(64),0(%r11) |
| 0: # check if base register setup + TIF bit load has been done |
| clg %r9,BASED(cleanup_system_call_insn+16) |
| jhe 0f |
| # set up saved registers r10 and r12 |
| stg %r10,16(%r11) # r10 last break |
| stg %r12,32(%r11) # r12 thread-info pointer |
| 0: # check if the user time update has been done |
| clg %r9,BASED(cleanup_system_call_insn+24) |
| jh 0f |
| lg %r15,__LC_EXIT_TIMER |
| slg %r15,__LC_SYNC_ENTER_TIMER |
| alg %r15,__LC_USER_TIMER |
| stg %r15,__LC_USER_TIMER |
| 0: # check if the system time update has been done |
| clg %r9,BASED(cleanup_system_call_insn+32) |
| jh 0f |
| lg %r15,__LC_LAST_UPDATE_TIMER |
| slg %r15,__LC_EXIT_TIMER |
| alg %r15,__LC_SYSTEM_TIMER |
| stg %r15,__LC_SYSTEM_TIMER |
| 0: # update accounting time stamp |
| mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER |
| # do LAST_BREAK |
| lg %r9,16(%r11) |
| srag %r9,%r9,23 |
| jz 0f |
| mvc __TI_last_break(8,%r12),16(%r11) |
| 0: # set up saved register r11 |
| lg %r15,__LC_KERNEL_STACK |
| aghi %r15,-__PT_SIZE |
| stg %r15,24(%r11) # r11 pt_regs pointer |
| # fill pt_regs |
| mvc __PT_R8(64,%r15),__LC_SAVE_AREA_SYNC |
| stmg %r0,%r7,__PT_R0(%r15) |
| mvc __PT_PSW(16,%r15),__LC_SVC_OLD_PSW |
| mvc __PT_INT_CODE(4,%r15),__LC_SVC_ILC |
| # setup saved register r15 |
| aghi %r15,-STACK_FRAME_OVERHEAD |
| stg %r15,56(%r11) # r15 stack pointer |
| # set new psw address and exit |
| larl %r9,sysc_do_svc |
| br %r14 |
| cleanup_system_call_insn: |
| .quad system_call |
| .quad sysc_stmg |
| .quad sysc_per |
| .quad sysc_vtime+18 |
| .quad sysc_vtime+42 |
| |
| cleanup_sysc_tif: |
| larl %r9,sysc_tif |
| br %r14 |
| |
| cleanup_sysc_restore: |
| clg %r9,BASED(cleanup_sysc_restore_insn) |
| je 0f |
| lg %r9,24(%r11) # get saved pointer to pt_regs |
| mvc __LC_RETURN_PSW(16),__PT_PSW(%r9) |
| mvc 0(64,%r11),__PT_R8(%r9) |
| lmg %r0,%r7,__PT_R0(%r9) |
| 0: lmg %r8,%r9,__LC_RETURN_PSW |
| br %r14 |
| cleanup_sysc_restore_insn: |
| .quad sysc_done - 4 |
| |
| cleanup_io_tif: |
| larl %r9,io_tif |
| br %r14 |
| |
| cleanup_io_restore: |
| clg %r9,BASED(cleanup_io_restore_insn) |
| je 0f |
| lg %r9,24(%r11) # get saved r11 pointer to pt_regs |
| mvc __LC_RETURN_PSW(16),__PT_PSW(%r9) |
| mvc 0(64,%r11),__PT_R8(%r9) |
| lmg %r0,%r7,__PT_R0(%r9) |
| 0: lmg %r8,%r9,__LC_RETURN_PSW |
| br %r14 |
| cleanup_io_restore_insn: |
| .quad io_done - 4 |
| |
| cleanup_idle: |
| # copy interrupt clock & cpu timer |
| mvc __CLOCK_IDLE_EXIT(8,%r2),__LC_INT_CLOCK |
| mvc __TIMER_IDLE_EXIT(8,%r2),__LC_ASYNC_ENTER_TIMER |
| cghi %r11,__LC_SAVE_AREA_ASYNC |
| je 0f |
| mvc __CLOCK_IDLE_EXIT(8,%r2),__LC_MCCK_CLOCK |
| mvc __TIMER_IDLE_EXIT(8,%r2),__LC_MCCK_ENTER_TIMER |
| 0: # check if stck & stpt have been executed |
| clg %r9,BASED(cleanup_idle_insn) |
| jhe 1f |
| mvc __CLOCK_IDLE_ENTER(8,%r2),__CLOCK_IDLE_EXIT(%r2) |
| mvc __TIMER_IDLE_ENTER(8,%r2),__TIMER_IDLE_EXIT(%r2) |
| 1: # account system time going idle |
| lg %r9,__LC_STEAL_TIMER |
| alg %r9,__CLOCK_IDLE_ENTER(%r2) |
| slg %r9,__LC_LAST_UPDATE_CLOCK |
| stg %r9,__LC_STEAL_TIMER |
| mvc __LC_LAST_UPDATE_CLOCK(8),__CLOCK_IDLE_EXIT(%r2) |
| lg %r9,__LC_SYSTEM_TIMER |
| alg %r9,__LC_LAST_UPDATE_TIMER |
| slg %r9,__TIMER_IDLE_ENTER(%r2) |
| stg %r9,__LC_SYSTEM_TIMER |
| mvc __LC_LAST_UPDATE_TIMER(8),__TIMER_IDLE_EXIT(%r2) |
| # prepare return psw |
| nihh %r8,0xfffd # clear wait state bit |
| lg %r9,48(%r11) # return from psw_idle |
| br %r14 |
| cleanup_idle_insn: |
| .quad psw_idle_lpsw |
| |
| /* |
| * Integer constants |
| */ |
| .align 8 |
| .Lcritical_start: |
| .quad __critical_start |
| .Lcritical_length: |
| .quad __critical_end - __critical_start |
| |
| |
| #if defined(CONFIG_KVM) || defined(CONFIG_KVM_MODULE) |
| /* |
| * sie64a calling convention: |
| * %r2 pointer to sie control block |
| * %r3 guest register save area |
| */ |
| ENTRY(sie64a) |
| stmg %r6,%r14,__SF_GPRS(%r15) # save kernel registers |
| stg %r2,__SF_EMPTY(%r15) # save control block pointer |
| stg %r3,__SF_EMPTY+8(%r15) # save guest register save area |
| xc __SF_EMPTY+16(8,%r15),__SF_EMPTY+16(%r15) # host id == 0 |
| lmg %r0,%r13,0(%r3) # load guest gprs 0-13 |
| sie_loop: |
| lg %r14,__LC_THREAD_INFO # pointer thread_info struct |
| tm __TI_flags+7(%r14),_TIF_EXIT_SIE |
| jnz sie_exit |
| lg %r14,__LC_GMAP # get gmap pointer |
| ltgr %r14,%r14 |
| jz sie_gmap |
| lctlg %c1,%c1,__GMAP_ASCE(%r14) # load primary asce |
| sie_gmap: |
| lg %r14,__SF_EMPTY(%r15) # get control block pointer |
| SPP __SF_EMPTY(%r15) # set guest id |
| sie 0(%r14) |
| sie_done: |
| SPP __SF_EMPTY+16(%r15) # set host id |
| lg %r14,__LC_THREAD_INFO # pointer thread_info struct |
| sie_exit: |
| lctlg %c1,%c1,__LC_USER_ASCE # load primary asce |
| lg %r14,__SF_EMPTY+8(%r15) # load guest register save area |
| stmg %r0,%r13,0(%r14) # save guest gprs 0-13 |
| lmg %r6,%r14,__SF_GPRS(%r15) # restore kernel registers |
| lghi %r2,0 |
| br %r14 |
| sie_fault: |
| lctlg %c1,%c1,__LC_USER_ASCE # load primary asce |
| lg %r14,__LC_THREAD_INFO # pointer thread_info struct |
| lg %r14,__SF_EMPTY+8(%r15) # load guest register save area |
| stmg %r0,%r13,0(%r14) # save guest gprs 0-13 |
| lmg %r6,%r14,__SF_GPRS(%r15) # restore kernel registers |
| lghi %r2,-EFAULT |
| br %r14 |
| |
| .align 8 |
| .Lsie_loop: |
| .quad sie_loop |
| .Lsie_length: |
| .quad sie_done - sie_loop |
| .Lhost_id: |
| .quad 0 |
| |
| .section __ex_table,"a" |
| .quad sie_loop,sie_fault |
| .previous |
| #endif |
| |
| .section .rodata, "a" |
| #define SYSCALL(esa,esame,emu) .long esame |
| .globl sys_call_table |
| sys_call_table: |
| #include "syscalls.S" |
| #undef SYSCALL |
| |
| #ifdef CONFIG_COMPAT |
| |
| #define SYSCALL(esa,esame,emu) .long emu |
| sys_call_table_emu: |
| #include "syscalls.S" |
| #undef SYSCALL |
| #endif |