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* arch/s390/kernel/entry.S
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* S390 low-level entry points.
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* Copyright (C) IBM Corp. 1999,2006
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* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
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* Hartmut Penner (hp@de.ibm.com),
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* Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
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* Heiko Carstens <heiko.carstens@de.ibm.com>
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#include <linux/init.h>
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#include <linux/linkage.h>
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#include <asm/cache.h>
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#include <asm/errno.h>
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#include <asm/ptrace.h>
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#include <asm/thread_info.h>
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#include <asm/asm-offsets.h>
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#include <asm/unistd.h>
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* Stack layout for the system_call stack entry.
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* The first few entries are identical to the user_regs_struct.
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SP_PTREGS = STACK_FRAME_OVERHEAD
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SP_ARGS = STACK_FRAME_OVERHEAD + __PT_ARGS
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SP_PSW = STACK_FRAME_OVERHEAD + __PT_PSW
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SP_R0 = STACK_FRAME_OVERHEAD + __PT_GPRS
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SP_R1 = STACK_FRAME_OVERHEAD + __PT_GPRS + 4
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SP_R2 = STACK_FRAME_OVERHEAD + __PT_GPRS + 8
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SP_R3 = STACK_FRAME_OVERHEAD + __PT_GPRS + 12
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SP_R4 = STACK_FRAME_OVERHEAD + __PT_GPRS + 16
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SP_R5 = STACK_FRAME_OVERHEAD + __PT_GPRS + 20
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SP_R6 = STACK_FRAME_OVERHEAD + __PT_GPRS + 24
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SP_R7 = STACK_FRAME_OVERHEAD + __PT_GPRS + 28
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SP_R8 = STACK_FRAME_OVERHEAD + __PT_GPRS + 32
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SP_R9 = STACK_FRAME_OVERHEAD + __PT_GPRS + 36
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SP_R10 = STACK_FRAME_OVERHEAD + __PT_GPRS + 40
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SP_R11 = STACK_FRAME_OVERHEAD + __PT_GPRS + 44
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SP_R12 = STACK_FRAME_OVERHEAD + __PT_GPRS + 48
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SP_R13 = STACK_FRAME_OVERHEAD + __PT_GPRS + 52
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SP_R14 = STACK_FRAME_OVERHEAD + __PT_GPRS + 56
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SP_R15 = STACK_FRAME_OVERHEAD + __PT_GPRS + 60
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SP_ORIG_R2 = STACK_FRAME_OVERHEAD + __PT_ORIG_GPR2
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SP_SVC_CODE = STACK_FRAME_OVERHEAD + __PT_SVC_CODE
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SP_SIZE = STACK_FRAME_OVERHEAD + __PT_SIZE
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_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
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_TIF_MCCK_PENDING | _TIF_PER_TRAP )
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_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
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_TIF_TRACE = (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | \
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_TIF_SYSCALL_TRACEPOINT)
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STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
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STACK_SIZE = 1 << STACK_SHIFT
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#define BASED(name) name-system_call(%r13)
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#ifdef CONFIG_TRACE_IRQFLAGS
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l %r1,BASED(.Ltrace_irq_on_caller)
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l %r1,BASED(.Ltrace_irq_off_caller)
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#define TRACE_IRQS_OFF
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.macro LOCKDEP_SYS_EXIT
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tm SP_PSW+1(%r15),0x01 # returning to user ?
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l %r1,BASED(.Llockdep_sys_exit)
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#define LOCKDEP_SYS_EXIT
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* Register usage in interrupt handlers:
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* R9 - pointer to current task structure
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* R13 - pointer to literal pool
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* R14 - return register for function calls
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* R15 - kernel stack pointer
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.macro UPDATE_VTIME lc_from,lc_to,lc_sum
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1: stm %r10,%r11,\lc_sum
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.macro SAVE_ALL_SVC psworg,savearea
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stm %r12,%r15,\savearea
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l %r13,__LC_SVC_NEW_PSW+4 # load &system_call to %r13
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l %r15,__LC_KERNEL_STACK # problem state -> load ksp
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s %r15,BASED(.Lc_spsize) # make room for registers & psw
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.macro SAVE_ALL_BASE savearea
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stm %r12,%r15,\savearea
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l %r13,__LC_SVC_NEW_PSW+4 # load &system_call to %r13
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.macro SAVE_ALL_PGM psworg,savearea
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tm \psworg+1,0x01 # test problem state bit
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#ifdef CONFIG_CHECK_STACK
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tml %r15,STACK_SIZE - CONFIG_STACK_GUARD
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b BASED(stack_overflow)
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1: l %r15,__LC_KERNEL_STACK # problem state -> load ksp
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2: s %r15,BASED(.Lc_spsize) # make room for registers & psw
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.macro SAVE_ALL_ASYNC psworg,savearea
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stm %r12,%r15,\savearea
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l %r13,__LC_SVC_NEW_PSW+4 # load &system_call to %r13
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tm \psworg+1,0x01 # test problem state bit
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bnz BASED(1f) # from user -> load async stack
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clc \psworg+4(4),BASED(.Lcritical_end)
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clc \psworg+4(4),BASED(.Lcritical_start)
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l %r14,BASED(.Lcleanup_critical)
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tm 1(%r12),0x01 # retest problem state after cleanup
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0: l %r14,__LC_ASYNC_STACK # are we already on the async stack ?
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#ifdef CONFIG_CHECK_STACK
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tml %r15,STACK_SIZE - CONFIG_STACK_GUARD
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b BASED(stack_overflow)
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1: l %r15,__LC_ASYNC_STACK
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2: s %r15,BASED(.Lc_spsize) # make room for registers & psw
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.macro CREATE_STACK_FRAME savearea
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xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
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st %r2,SP_ORIG_R2(%r15) # store original content of gpr 2
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mvc SP_R12(16,%r15),\savearea # move %r12-%r15 to stack
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stm %r0,%r11,SP_R0(%r15) # store gprs %r0-%r11 to kernel stack
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.macro RESTORE_ALL psworg,sync
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mvc \psworg(8),SP_PSW(%r15) # move user PSW to lowcore
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ni \psworg+1,0xfd # clear wait state bit
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lm %r0,%r15,SP_R0(%r15) # load gprs 0-15 of user
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lpsw \psworg # back to caller
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mvc __SF_EMPTY(1,%r15),SP_PSW(%r15)
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ni __SF_EMPTY(%r15),0xbf
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.section .kprobes.text, "ax"
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* Scheduler resume function, called by switch_to
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* gpr2 = (task_struct *) prev
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* gpr3 = (task_struct *) next
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0: l %r4,__THREAD_info(%r2) # get thread_info of prev
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l %r5,__THREAD_info(%r3) # get thread_info of next
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tm __TI_flags+3(%r4),_TIF_MCCK_PENDING # machine check pending?
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ni __TI_flags+3(%r4),255-_TIF_MCCK_PENDING # clear flag in prev
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oi __TI_flags+3(%r5),_TIF_MCCK_PENDING # set it in next
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1: stm %r6,%r15,__SF_GPRS(%r15) # store gprs of prev task
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st %r15,__THREAD_ksp(%r2) # store kernel stack of prev
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l %r15,__THREAD_ksp(%r3) # load kernel stack of next
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lctl %c4,%c4,__TASK_pid(%r3) # load pid to control reg. 4
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lm %r6,%r15,__SF_GPRS(%r15) # load gprs of next task
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st %r3,__LC_CURRENT # store task struct of next
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mvc __LC_CURRENT_PID(4,%r0),__TASK_pid(%r3) # store pid of next
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st %r5,__LC_THREAD_INFO # store thread info of next
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ahi %r5,STACK_SIZE # end of kernel stack of next
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st %r5,__LC_KERNEL_STACK # store end of kernel stack
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* SVC interrupt handler routine. System calls are synchronous events and
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* are executed with interrupts enabled.
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stpt __LC_SYNC_ENTER_TIMER
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SAVE_ALL_SVC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
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CREATE_STACK_FRAME __LC_SAVE_AREA
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l %r12,__LC_THREAD_INFO # load pointer to thread_info struct
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mvc SP_PSW(8,%r15),__LC_SVC_OLD_PSW
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mvc SP_SVC_CODE(4,%r15),__LC_SVC_ILC
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oi __TI_flags+3(%r12),_TIF_SYSCALL
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UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
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UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
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mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
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icm %r7,3,SP_SVC_CODE+2(%r15)# load svc number and test for svc 0
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bnz BASED(sysc_nr_ok) # svc number > 0
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# svc 0: system call number in %r1
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cl %r1,BASED(.Lnr_syscalls)
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bnl BASED(sysc_nr_ok)
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sth %r1,SP_SVC_CODE+2(%r15)
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lr %r7,%r1 # copy svc number to %r7
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sll %r7,2 # svc number *4
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l %r10,BASED(.Lsysc_table)
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tm __TI_flags+2(%r12),_TIF_TRACE >> 8
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mvc SP_ARGS(4,%r15),SP_R7(%r15)
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l %r8,0(%r7,%r10) # get system call addr.
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bnz BASED(sysc_tracesys)
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basr %r14,%r8 # call sys_xxxx
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st %r2,SP_R2(%r15) # store return value (change R2 on stack)
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tm SP_PSW+1(%r15),0x01 # returning to user ?
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bno BASED(sysc_restore)
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tm __TI_flags+3(%r12),_TIF_WORK_SVC
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bnz BASED(sysc_work) # there is work to do (signals etc.)
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ni __TI_flags+3(%r12),255-_TIF_SYSCALL
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RESTORE_ALL __LC_RETURN_PSW,1
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# One of the work bits is on. Find out which one.
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tm __TI_flags+3(%r12),_TIF_MCCK_PENDING
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bo BASED(sysc_mcck_pending)
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tm __TI_flags+3(%r12),_TIF_NEED_RESCHED
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bo BASED(sysc_reschedule)
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tm __TI_flags+3(%r12),_TIF_SIGPENDING
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bo BASED(sysc_sigpending)
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tm __TI_flags+3(%r12),_TIF_NOTIFY_RESUME
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bo BASED(sysc_notify_resume)
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tm __TI_flags+3(%r12),_TIF_PER_TRAP
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bo BASED(sysc_singlestep)
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b BASED(sysc_return) # beware of critical section cleanup
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# _TIF_NEED_RESCHED is set, call schedule
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l %r1,BASED(.Lschedule)
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la %r14,BASED(sysc_return)
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br %r1 # call scheduler
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# _TIF_MCCK_PENDING is set, call handler
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l %r1,BASED(.Ls390_handle_mcck)
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la %r14,BASED(sysc_return)
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br %r1 # TIF bit will be cleared by handler
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# _TIF_SIGPENDING is set, call do_signal
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ni __TI_flags+3(%r12),255-_TIF_PER_TRAP # clear TIF_PER_TRAP
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la %r2,SP_PTREGS(%r15) # load pt_regs
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l %r1,BASED(.Ldo_signal)
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basr %r14,%r1 # call do_signal
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tm __TI_flags+3(%r12),_TIF_SYSCALL
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bno BASED(sysc_return)
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lm %r2,%r6,SP_R2(%r15) # load svc arguments
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xr %r7,%r7 # svc 0 returns -ENOSYS
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clc SP_SVC_CODE+2(2,%r15),BASED(.Lnr_syscalls+2)
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bnl BASED(sysc_nr_ok) # invalid svc number -> do svc 0
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icm %r7,3,SP_SVC_CODE+2(%r15)# load new svc number
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b BASED(sysc_nr_ok) # restart svc
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# _TIF_NOTIFY_RESUME is set, call do_notify_resume
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la %r2,SP_PTREGS(%r15) # load pt_regs
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l %r1,BASED(.Ldo_notify_resume)
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la %r14,BASED(sysc_return)
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br %r1 # call do_notify_resume
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# _TIF_PER_TRAP is set, call do_per_trap
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ni __TI_flags+3(%r12),255-(_TIF_SYSCALL | _TIF_PER_TRAP)
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la %r2,SP_PTREGS(%r15) # address of register-save area
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l %r1,BASED(.Lhandle_per) # load adr. of per handler
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la %r14,BASED(sysc_return) # load adr. of system return
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br %r1 # branch to do_per_trap
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# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
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# and after the system call
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l %r1,BASED(.Ltrace_entry)
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la %r2,SP_PTREGS(%r15) # load pt_regs
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icm %r0,3,SP_SVC_CODE(%r15)
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cl %r2,BASED(.Lnr_syscalls)
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bnl BASED(sysc_tracenogo)
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sll %r7,2 # svc number *4
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lm %r3,%r6,SP_R3(%r15)
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mvc SP_ARGS(4,%r15),SP_R7(%r15)
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l %r2,SP_ORIG_R2(%r15)
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basr %r14,%r8 # call sys_xxx
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st %r2,SP_R2(%r15) # store return value
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tm __TI_flags+2(%r12),_TIF_TRACE >> 8
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bz BASED(sysc_return)
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l %r1,BASED(.Ltrace_exit)
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la %r2,SP_PTREGS(%r15) # load pt_regs
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la %r14,BASED(sysc_return)
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# a new process exits the kernel with ret_from_fork
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l %r13,__LC_SVC_NEW_PSW+4
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l %r12,__LC_THREAD_INFO # load pointer to thread_info struct
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tm SP_PSW+1(%r15),0x01 # forking a kernel thread ?
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st %r15,SP_R15(%r15) # store stack pointer for new kthread
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0: l %r1,BASED(.Lschedtail)
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stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
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b BASED(sysc_tracenogo)
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# kernel_execve function needs to deal with pt_regs that is not
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stm %r12,%r15,48(%r15)
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l %r13,__LC_SVC_NEW_PSW+4
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s %r15,BASED(.Lc_spsize)
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st %r14,__SF_BACKCHAIN(%r15)
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la %r12,SP_PTREGS(%r15)
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xc 0(__PT_SIZE,%r12),0(%r12)
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l %r1,BASED(.Ldo_execve)
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a %r15,BASED(.Lc_spsize)
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lm %r12,%r15,48(%r15)
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0: stnsm __SF_EMPTY(%r15),0xfc # disable interrupts
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l %r15,__LC_KERNEL_STACK # load ksp
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s %r15,BASED(.Lc_spsize) # make room for registers & psw
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mvc SP_PTREGS(__PT_SIZE,%r15),0(%r12) # copy pt_regs
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l %r12,__LC_THREAD_INFO
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xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
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stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
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l %r1,BASED(.Lexecve_tail)
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* Program check handler routine
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ENTRY(pgm_check_handler)
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* First we need to check for a special case:
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* Single stepping an instruction that disables the PER event mask will
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* cause a PER event AFTER the mask has been set. Example: SVC or LPSW.
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* For a single stepped SVC the program check handler gets control after
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* the SVC new PSW has been loaded. But we want to execute the SVC first and
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* then handle the PER event. Therefore we update the SVC old PSW to point
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* to the pgm_check_handler and branch to the SVC handler after we checked
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* if we have to load the kernel stack register.
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* For every other possible cause for PER event without the PER mask set
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* we just ignore the PER event (FIXME: is there anything we have to do
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stpt __LC_SYNC_ENTER_TIMER
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SAVE_ALL_BASE __LC_SAVE_AREA
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tm __LC_PGM_INT_CODE+1,0x80 # check whether we got a per exception
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bnz BASED(pgm_per) # got per exception -> special case
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SAVE_ALL_PGM __LC_PGM_OLD_PSW,__LC_SAVE_AREA
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CREATE_STACK_FRAME __LC_SAVE_AREA
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mvc SP_PSW(8,%r15),__LC_PGM_OLD_PSW
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l %r12,__LC_THREAD_INFO # load pointer to thread_info struct
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tm SP_PSW+1(%r15),0x01 # interrupting from user ?
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bz BASED(pgm_no_vtime)
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UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
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UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
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mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
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l %r3,__LC_PGM_ILC # load program interruption code
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l %r4,__LC_TRANS_EXC_CODE
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l %r1,BASED(.Ljump_table)
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l %r1,0(%r8,%r1) # load address of handler routine
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la %r2,SP_PTREGS(%r15) # address of register-save area
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basr %r14,%r1 # branch to interrupt-handler
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# handle per exception
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tm __LC_PGM_OLD_PSW,0x40 # test if per event recording is on
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bnz BASED(pgm_per_std) # ok, normal per event from user space
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# ok its one of the special cases, now we need to find out which one
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clc __LC_PGM_OLD_PSW(8),__LC_SVC_NEW_PSW
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# no interesting special case, ignore PER event
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lm %r12,%r15,__LC_SAVE_AREA
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# Normal per exception
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SAVE_ALL_PGM __LC_PGM_OLD_PSW,__LC_SAVE_AREA
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CREATE_STACK_FRAME __LC_SAVE_AREA
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mvc SP_PSW(8,%r15),__LC_PGM_OLD_PSW
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l %r12,__LC_THREAD_INFO # load pointer to thread_info struct
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tm SP_PSW+1(%r15),0x01 # interrupting from user ?
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bz BASED(pgm_no_vtime2)
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UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
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UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
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mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
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l %r1,__TI_task(%r12)
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tm SP_PSW+1(%r15),0x01 # kernel per event ?
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mvc __THREAD_per_cause(2,%r1),__LC_PER_CAUSE
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mvc __THREAD_per_address(4,%r1),__LC_PER_ADDRESS
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mvc __THREAD_per_paid(1,%r1),__LC_PER_PAID
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oi __TI_flags+3(%r12),_TIF_PER_TRAP # set TIF_PER_TRAP
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l %r3,__LC_PGM_ILC # load program interruption code
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l %r4,__LC_TRANS_EXC_CODE
500
nr %r8,%r3 # clear per-event-bit and ilc
501
be BASED(pgm_exit2) # only per or per+check ?
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l %r1,BASED(.Ljump_table)
504
l %r1,0(%r8,%r1) # load address of handler routine
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la %r2,SP_PTREGS(%r15) # address of register-save area
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basr %r14,%r1 # branch to interrupt-handler
511
# it was a single stepped SVC that is causing all the trouble
514
SAVE_ALL_PGM __LC_SVC_OLD_PSW,__LC_SAVE_AREA
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CREATE_STACK_FRAME __LC_SAVE_AREA
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l %r12,__LC_THREAD_INFO # load pointer to thread_info struct
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mvc SP_PSW(8,%r15),__LC_SVC_OLD_PSW
518
mvc SP_SVC_CODE(4,%r15),__LC_SVC_ILC
519
oi __TI_flags+3(%r12),(_TIF_SYSCALL | _TIF_PER_TRAP)
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UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
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UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
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mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
523
l %r8,__TI_task(%r12)
524
mvc __THREAD_per_cause(2,%r8),__LC_PER_CAUSE
525
mvc __THREAD_per_address(4,%r8),__LC_PER_ADDRESS
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mvc __THREAD_per_paid(1,%r8),__LC_PER_PAID
527
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
528
lm %r2,%r6,SP_R2(%r15) # load svc arguments
532
# per was called from kernel, must be kprobes
536
la %r2,SP_PTREGS(%r15) # address of register-save area
537
l %r1,BASED(.Lhandle_per) # load adr. of per handler
538
basr %r14,%r1 # branch to do_single_step
542
* IO interrupt handler routine
545
ENTRY(io_int_handler)
547
stpt __LC_ASYNC_ENTER_TIMER
548
SAVE_ALL_ASYNC __LC_IO_OLD_PSW,__LC_SAVE_AREA+16
549
CREATE_STACK_FRAME __LC_SAVE_AREA+16
550
mvc SP_PSW(8,%r15),0(%r12) # move user PSW to stack
551
l %r12,__LC_THREAD_INFO # load pointer to thread_info struct
552
tm SP_PSW+1(%r15),0x01 # interrupting from user ?
553
bz BASED(io_no_vtime)
554
UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
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UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
556
mvc __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
559
l %r1,BASED(.Ldo_IRQ) # load address of do_IRQ
560
la %r2,SP_PTREGS(%r15) # address of register-save area
561
basr %r14,%r1 # branch to standard irq handler
566
tm __TI_flags+3(%r12),_TIF_WORK_INT
567
bnz BASED(io_work) # there is work to do (signals etc.)
569
RESTORE_ALL __LC_RETURN_PSW,0
573
# There is work todo, find out in which context we have been interrupted:
574
# 1) if we return to user space we can do all _TIF_WORK_INT work
575
# 2) if we return to kernel code and preemptive scheduling is enabled check
576
# the preemption counter and if it is zero call preempt_schedule_irq
577
# Before any work can be done, a switch to the kernel stack is required.
580
tm SP_PSW+1(%r15),0x01 # returning to user ?
581
bo BASED(io_work_user) # yes -> do resched & signal
582
#ifdef CONFIG_PREEMPT
583
# check for preemptive scheduling
584
icm %r0,15,__TI_precount(%r12)
585
bnz BASED(io_restore) # preemption disabled
586
tm __TI_flags+3(%r12),_TIF_NEED_RESCHED
587
bno BASED(io_restore)
588
# switch to kernel stack
590
s %r1,BASED(.Lc_spsize)
591
mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
592
xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain
594
# TRACE_IRQS_ON already done at io_return, call
595
# TRACE_IRQS_OFF to keep things symmetrical
597
l %r1,BASED(.Lpreempt_schedule_irq)
598
basr %r14,%r1 # call preempt_schedule_irq
605
# Need to do work before returning to userspace, switch to kernel stack
608
l %r1,__LC_KERNEL_STACK
609
s %r1,BASED(.Lc_spsize)
610
mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
611
xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain
615
# One of the work bits is on. Find out which one.
616
# Checked are: _TIF_SIGPENDING, _TIF_NOTIFY_RESUME, _TIF_NEED_RESCHED
617
# and _TIF_MCCK_PENDING
620
tm __TI_flags+3(%r12),_TIF_MCCK_PENDING
621
bo BASED(io_mcck_pending)
622
tm __TI_flags+3(%r12),_TIF_NEED_RESCHED
623
bo BASED(io_reschedule)
624
tm __TI_flags+3(%r12),_TIF_SIGPENDING
625
bo BASED(io_sigpending)
626
tm __TI_flags+3(%r12),_TIF_NOTIFY_RESUME
627
bo BASED(io_notify_resume)
628
b BASED(io_return) # beware of critical section cleanup
631
# _TIF_MCCK_PENDING is set, call handler
634
# TRACE_IRQS_ON already done at io_return
635
l %r1,BASED(.Ls390_handle_mcck)
636
basr %r14,%r1 # TIF bit will be cleared by handler
641
# _TIF_NEED_RESCHED is set, call schedule
644
# TRACE_IRQS_ON already done at io_return
645
l %r1,BASED(.Lschedule)
646
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
647
basr %r14,%r1 # call scheduler
648
stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
653
# _TIF_SIGPENDING is set, call do_signal
656
# TRACE_IRQS_ON already done at io_return
657
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
658
la %r2,SP_PTREGS(%r15) # load pt_regs
659
l %r1,BASED(.Ldo_signal)
660
basr %r14,%r1 # call do_signal
661
stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
666
# _TIF_SIGPENDING is set, call do_signal
669
# TRACE_IRQS_ON already done at io_return
670
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
671
la %r2,SP_PTREGS(%r15) # load pt_regs
672
l %r1,BASED(.Ldo_notify_resume)
673
basr %r14,%r1 # call do_signal
674
stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
679
* External interrupt handler routine
682
ENTRY(ext_int_handler)
684
stpt __LC_ASYNC_ENTER_TIMER
685
SAVE_ALL_ASYNC __LC_EXT_OLD_PSW,__LC_SAVE_AREA+16
686
CREATE_STACK_FRAME __LC_SAVE_AREA+16
687
mvc SP_PSW(8,%r15),0(%r12) # move user PSW to stack
688
l %r12,__LC_THREAD_INFO # load pointer to thread_info struct
689
tm SP_PSW+1(%r15),0x01 # interrupting from user ?
690
bz BASED(ext_no_vtime)
691
UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
692
UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
693
mvc __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
696
la %r2,SP_PTREGS(%r15) # address of register-save area
697
l %r3,__LC_CPU_ADDRESS # get cpu address + interruption code
698
l %r4,__LC_EXT_PARAMS # get external parameters
699
l %r1,BASED(.Ldo_extint)
706
* Machine check handler routines
709
ENTRY(mcck_int_handler)
711
spt __LC_CPU_TIMER_SAVE_AREA # revalidate cpu timer
712
lm %r0,%r15,__LC_GPREGS_SAVE_AREA # revalidate gprs
713
SAVE_ALL_BASE __LC_SAVE_AREA+32
714
la %r12,__LC_MCK_OLD_PSW
715
tm __LC_MCCK_CODE,0x80 # system damage?
716
bo BASED(mcck_int_main) # yes -> rest of mcck code invalid
717
mvc __LC_MCCK_ENTER_TIMER(8),__LC_CPU_TIMER_SAVE_AREA
718
tm __LC_MCCK_CODE+5,0x02 # stored cpu timer value valid?
720
la %r14,__LC_SYNC_ENTER_TIMER
721
clc 0(8,%r14),__LC_ASYNC_ENTER_TIMER
723
la %r14,__LC_ASYNC_ENTER_TIMER
724
0: clc 0(8,%r14),__LC_EXIT_TIMER
726
la %r14,__LC_EXIT_TIMER
727
0: clc 0(8,%r14),__LC_LAST_UPDATE_TIMER
729
la %r14,__LC_LAST_UPDATE_TIMER
731
mvc __LC_MCCK_ENTER_TIMER(8),0(%r14)
732
1: tm __LC_MCCK_CODE+2,0x09 # mwp + ia of old psw valid?
733
bno BASED(mcck_int_main) # no -> skip cleanup critical
734
tm __LC_MCK_OLD_PSW+1,0x01 # test problem state bit
735
bnz BASED(mcck_int_main) # from user -> load async stack
736
clc __LC_MCK_OLD_PSW+4(4),BASED(.Lcritical_end)
737
bhe BASED(mcck_int_main)
738
clc __LC_MCK_OLD_PSW+4(4),BASED(.Lcritical_start)
739
bl BASED(mcck_int_main)
740
l %r14,BASED(.Lcleanup_critical)
743
l %r14,__LC_PANIC_STACK # are we already on the panic stack?
747
l %r15,__LC_PANIC_STACK # load panic stack
748
0: s %r15,BASED(.Lc_spsize) # make room for registers & psw
749
CREATE_STACK_FRAME __LC_SAVE_AREA+32
750
mvc SP_PSW(8,%r15),0(%r12)
751
l %r12,__LC_THREAD_INFO # load pointer to thread_info struct
752
tm __LC_MCCK_CODE+2,0x08 # mwp of old psw valid?
753
bno BASED(mcck_no_vtime) # no -> skip cleanup critical
754
tm SP_PSW+1(%r15),0x01 # interrupting from user ?
755
bz BASED(mcck_no_vtime)
756
UPDATE_VTIME __LC_EXIT_TIMER,__LC_MCCK_ENTER_TIMER,__LC_USER_TIMER
757
UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
758
mvc __LC_LAST_UPDATE_TIMER(8),__LC_MCCK_ENTER_TIMER
760
la %r2,SP_PTREGS(%r15) # load pt_regs
761
l %r1,BASED(.Ls390_mcck)
762
basr %r14,%r1 # call machine check handler
763
tm SP_PSW+1(%r15),0x01 # returning to user ?
764
bno BASED(mcck_return)
765
l %r1,__LC_KERNEL_STACK # switch to kernel stack
766
s %r1,BASED(.Lc_spsize)
767
mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
768
xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain
770
stosm __SF_EMPTY(%r15),0x04 # turn dat on
771
tm __TI_flags+3(%r12),_TIF_MCCK_PENDING
772
bno BASED(mcck_return)
774
l %r1,BASED(.Ls390_handle_mcck)
775
basr %r14,%r1 # call machine check handler
778
mvc __LC_RETURN_MCCK_PSW(8),SP_PSW(%r15) # move return PSW
779
ni __LC_RETURN_MCCK_PSW+1,0xfd # clear wait state bit
780
tm __LC_RETURN_MCCK_PSW+1,0x01 # returning to user ?
782
lm %r0,%r15,SP_R0(%r15) # load gprs 0-15
784
lpsw __LC_RETURN_MCCK_PSW # back to caller
785
0: lm %r0,%r15,SP_R0(%r15) # load gprs 0-15
786
lpsw __LC_RETURN_MCCK_PSW # back to caller
788
RESTORE_ALL __LC_RETURN_MCCK_PSW,0
791
* Restart interruption handler, kick starter for additional CPUs
795
ENTRY(restart_int_handler)
798
spt restart_vtime-restart_base(%r1)
799
stck __LC_LAST_UPDATE_CLOCK
800
mvc __LC_LAST_UPDATE_TIMER(8),restart_vtime-restart_base(%r1)
801
mvc __LC_EXIT_TIMER(8),restart_vtime-restart_base(%r1)
802
l %r15,__LC_SAVE_AREA+60 # load ksp
803
lctl %c0,%c15,__LC_CREGS_SAVE_AREA # get new ctl regs
804
lam %a0,%a15,__LC_AREGS_SAVE_AREA
805
lm %r6,%r15,__SF_GPRS(%r15) # load registers from clone
806
l %r1,__LC_THREAD_INFO
807
mvc __LC_USER_TIMER(8),__TI_user_timer(%r1)
808
mvc __LC_SYSTEM_TIMER(8),__TI_system_timer(%r1)
809
xc __LC_STEAL_TIMER(8),__LC_STEAL_TIMER
810
stosm __SF_EMPTY(%r15),0x04 # now we can turn dat on
812
l %r14,restart_addr-.(%r14)
813
basr %r14,%r14 # branch to start_secondary
815
.long start_secondary
818
.long 0x7fffffff,0xffffffff
822
* If we do not run with SMP enabled, let the new CPU crash ...
824
ENTRY(restart_int_handler)
827
lpsw restart_crash-restart_base(%r1)
830
.long 0x000a0000,0x00000000
835
# PSW restart interrupt handler
837
ENTRY(psw_restart_int_handler)
838
st %r15,__LC_SAVE_AREA+48(%r0) # save r15
840
0: l %r15,.Lrestart_stack-0b(%r15) # load restart stack
842
ahi %r15,-SP_SIZE # make room for pt_regs
843
stm %r0,%r14,SP_R0(%r15) # store gprs %r0-%r14 to stack
844
mvc SP_R15(4,%r15),__LC_SAVE_AREA+48(%r0)# store saved %r15 to stack
845
mvc SP_PSW(8,%r15),__LC_RST_OLD_PSW(%r0) # store restart old psw
846
xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) # set backchain to 0
848
1: l %r14,.Ldo_restart-1b(%r14)
851
basr %r14,0 # load disabled wait PSW if
852
2: lpsw restart_psw_crash-2b(%r14) # do_restart returns
860
.long 0x000a0000,0x00000000 + restart_psw_crash
862
.section .kprobes.text, "ax"
864
#ifdef CONFIG_CHECK_STACK
866
* The synchronous or the asynchronous stack overflowed. We are dead.
867
* No need to properly save the registers, we are going to panic anyway.
868
* Setup a pt_regs so that show_trace can provide a good call trace.
871
l %r15,__LC_PANIC_STACK # change to panic stack
872
sl %r15,BASED(.Lc_spsize)
873
mvc SP_PSW(8,%r15),0(%r12) # move user PSW to stack
874
stm %r0,%r11,SP_R0(%r15) # store gprs %r0-%r11 to kernel stack
875
la %r1,__LC_SAVE_AREA
876
ch %r12,BASED(.L0x020) # old psw addr == __LC_SVC_OLD_PSW ?
878
ch %r12,BASED(.L0x028) # old psw addr == __LC_PGM_OLD_PSW ?
880
la %r1,__LC_SAVE_AREA+16
881
0: mvc SP_R12(16,%r15),0(%r1) # move %r12-%r15 to stack
882
xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) # clear back chain
883
l %r1,BASED(1f) # branch to kernel_stack_overflow
884
la %r2,SP_PTREGS(%r15) # load pt_regs
886
1: .long kernel_stack_overflow
889
cleanup_table_system_call:
890
.long system_call + 0x80000000, sysc_do_svc + 0x80000000
891
cleanup_table_sysc_tif:
892
.long sysc_tif + 0x80000000, sysc_restore + 0x80000000
893
cleanup_table_sysc_restore:
894
.long sysc_restore + 0x80000000, sysc_done + 0x80000000
895
cleanup_table_io_tif:
896
.long io_tif + 0x80000000, io_restore + 0x80000000
897
cleanup_table_io_restore:
898
.long io_restore + 0x80000000, io_done + 0x80000000
901
clc 4(4,%r12),BASED(cleanup_table_system_call)
903
clc 4(4,%r12),BASED(cleanup_table_system_call+4)
904
bl BASED(cleanup_system_call)
906
clc 4(4,%r12),BASED(cleanup_table_sysc_tif)
908
clc 4(4,%r12),BASED(cleanup_table_sysc_tif+4)
909
bl BASED(cleanup_sysc_tif)
911
clc 4(4,%r12),BASED(cleanup_table_sysc_restore)
913
clc 4(4,%r12),BASED(cleanup_table_sysc_restore+4)
914
bl BASED(cleanup_sysc_restore)
916
clc 4(4,%r12),BASED(cleanup_table_io_tif)
918
clc 4(4,%r12),BASED(cleanup_table_io_tif+4)
919
bl BASED(cleanup_io_tif)
921
clc 4(4,%r12),BASED(cleanup_table_io_restore)
923
clc 4(4,%r12),BASED(cleanup_table_io_restore+4)
924
bl BASED(cleanup_io_restore)
929
mvc __LC_RETURN_PSW(8),0(%r12)
930
clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+4)
932
mvc __LC_SYNC_ENTER_TIMER(8),__LC_MCCK_ENTER_TIMER
933
c %r12,BASED(.Lmck_old_psw)
935
mvc __LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER
936
0: c %r12,BASED(.Lmck_old_psw)
937
la %r12,__LC_SAVE_AREA+32
939
la %r12,__LC_SAVE_AREA+16
940
0: clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+8)
941
bhe BASED(cleanup_vtime)
942
clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn)
944
mvc __LC_SAVE_AREA(16),0(%r12)
946
l %r15,__LC_KERNEL_STACK # problem state -> load ksp
947
s %r15,BASED(.Lc_spsize) # make room for registers & psw
949
CREATE_STACK_FRAME __LC_SAVE_AREA
950
mvc 0(4,%r12),__LC_THREAD_INFO
951
l %r12,__LC_THREAD_INFO
952
mvc SP_PSW(8,%r15),__LC_SVC_OLD_PSW
953
mvc SP_SVC_CODE(4,%r15),__LC_SVC_ILC
954
oi __TI_flags+3(%r12),_TIF_SYSCALL
956
clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+12)
957
bhe BASED(cleanup_stime)
958
UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
960
clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+16)
961
bh BASED(cleanup_update)
962
UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
964
mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
965
mvc __LC_RETURN_PSW+4(4),BASED(cleanup_table_system_call+4)
966
la %r12,__LC_RETURN_PSW
968
cleanup_system_call_insn:
969
.long sysc_saveall + 0x80000000
970
.long system_call + 0x80000000
971
.long sysc_vtime + 0x80000000
972
.long sysc_stime + 0x80000000
973
.long sysc_update + 0x80000000
976
mvc __LC_RETURN_PSW(4),0(%r12)
977
mvc __LC_RETURN_PSW+4(4),BASED(cleanup_table_sysc_tif)
978
la %r12,__LC_RETURN_PSW
981
cleanup_sysc_restore:
982
clc 4(4,%r12),BASED(cleanup_sysc_restore_insn)
984
mvc __LC_EXIT_TIMER(8),__LC_MCCK_ENTER_TIMER
985
c %r12,BASED(.Lmck_old_psw)
987
mvc __LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER
988
0: clc 4(4,%r12),BASED(cleanup_sysc_restore_insn+4)
990
mvc __LC_RETURN_PSW(8),SP_PSW(%r15)
991
c %r12,BASED(.Lmck_old_psw)
992
la %r12,__LC_SAVE_AREA+32
994
la %r12,__LC_SAVE_AREA+16
995
1: mvc 0(16,%r12),SP_R12(%r15)
996
lm %r0,%r11,SP_R0(%r15)
998
2: la %r12,__LC_RETURN_PSW
1000
cleanup_sysc_restore_insn:
1001
.long sysc_done - 4 + 0x80000000
1002
.long sysc_done - 8 + 0x80000000
1005
mvc __LC_RETURN_PSW(4),0(%r12)
1006
mvc __LC_RETURN_PSW+4(4),BASED(cleanup_table_io_tif)
1007
la %r12,__LC_RETURN_PSW
1011
clc 4(4,%r12),BASED(cleanup_io_restore_insn)
1013
mvc __LC_EXIT_TIMER(8),__LC_MCCK_ENTER_TIMER
1014
clc 4(4,%r12),BASED(cleanup_io_restore_insn+4)
1016
mvc __LC_RETURN_PSW(8),SP_PSW(%r15)
1017
mvc __LC_SAVE_AREA+32(16),SP_R12(%r15)
1018
lm %r0,%r11,SP_R0(%r15)
1020
1: la %r12,__LC_RETURN_PSW
1022
cleanup_io_restore_insn:
1023
.long io_done - 4 + 0x80000000
1024
.long io_done - 8 + 0x80000000
1030
.Lc_spsize: .long SP_SIZE
1031
.Lc_overhead: .long STACK_FRAME_OVERHEAD
1032
.Lnr_syscalls: .long NR_syscalls
1033
.L0x018: .short 0x018
1034
.L0x020: .short 0x020
1035
.L0x028: .short 0x028
1036
.L0x030: .short 0x030
1037
.L0x038: .short 0x038
1043
.Ls390_mcck: .long s390_do_machine_check
1045
.long s390_handle_mcck
1046
.Lmck_old_psw: .long __LC_MCK_OLD_PSW
1047
.Ldo_IRQ: .long do_IRQ
1048
.Ldo_extint: .long do_extint
1049
.Ldo_signal: .long do_signal
1051
.long do_notify_resume
1052
.Lhandle_per: .long do_per_trap
1053
.Ldo_execve: .long do_execve
1054
.Lexecve_tail: .long execve_tail
1055
.Ljump_table: .long pgm_check_table
1056
.Lschedule: .long schedule
1057
#ifdef CONFIG_PREEMPT
1058
.Lpreempt_schedule_irq:
1059
.long preempt_schedule_irq
1061
.Ltrace_entry: .long do_syscall_trace_enter
1062
.Ltrace_exit: .long do_syscall_trace_exit
1063
.Lschedtail: .long schedule_tail
1064
.Lsysc_table: .long sys_call_table
1065
#ifdef CONFIG_TRACE_IRQFLAGS
1066
.Ltrace_irq_on_caller:
1067
.long trace_hardirqs_on_caller
1068
.Ltrace_irq_off_caller:
1069
.long trace_hardirqs_off_caller
1071
#ifdef CONFIG_LOCKDEP
1073
.long lockdep_sys_exit
1076
.long __critical_start + 0x80000000
1078
.long __critical_end + 0x80000000
1080
.long cleanup_critical
1082
.section .rodata, "a"
1083
#define SYSCALL(esa,esame,emu) .long esa
1084
.globl sys_call_table
1086
#include "syscalls.S"