951 lines
26 KiB
ArmAsm
951 lines
26 KiB
ArmAsm
/*
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* arch/s390/kernel/entry.S
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* S390 low-level entry points.
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*
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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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*/
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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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#include <asm/page.h>
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__PT_R0 = __PT_GPRS
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__PT_R1 = __PT_GPRS + 4
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__PT_R2 = __PT_GPRS + 8
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__PT_R3 = __PT_GPRS + 12
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__PT_R4 = __PT_GPRS + 16
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__PT_R5 = __PT_GPRS + 20
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__PT_R6 = __PT_GPRS + 24
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__PT_R7 = __PT_GPRS + 28
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__PT_R8 = __PT_GPRS + 32
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__PT_R9 = __PT_GPRS + 36
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__PT_R10 = __PT_GPRS + 40
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__PT_R11 = __PT_GPRS + 44
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__PT_R12 = __PT_GPRS + 48
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__PT_R13 = __PT_GPRS + 524
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__PT_R14 = __PT_GPRS + 56
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__PT_R15 = __PT_GPRS + 60
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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_MCCK_PENDING)
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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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.macro TRACE_IRQS_ON
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#ifdef CONFIG_TRACE_IRQFLAGS
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basr %r2,%r0
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l %r1,BASED(.Lhardirqs_on)
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basr %r14,%r1 # call trace_hardirqs_on_caller
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#endif
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.endm
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.macro TRACE_IRQS_OFF
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#ifdef CONFIG_TRACE_IRQFLAGS
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basr %r2,%r0
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l %r1,BASED(.Lhardirqs_off)
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basr %r14,%r1 # call trace_hardirqs_off_caller
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#endif
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.endm
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.macro LOCKDEP_SYS_EXIT
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#ifdef CONFIG_LOCKDEP
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tm __PT_PSW+1(%r11),0x01 # returning to user ?
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jz .+10
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l %r1,BASED(.Llockdep_sys_exit)
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basr %r14,%r1 # call lockdep_sys_exit
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#endif
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.endm
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.macro CHECK_STACK stacksize,savearea
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#ifdef CONFIG_CHECK_STACK
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tml %r15,\stacksize - CONFIG_STACK_GUARD
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la %r14,\savearea
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jz stack_overflow
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#endif
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.endm
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.macro SWITCH_ASYNC savearea,stack,shift
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tmh %r8,0x0001 # interrupting from user ?
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jnz 1f
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lr %r14,%r9
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sl %r14,BASED(.Lcritical_start)
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cl %r14,BASED(.Lcritical_length)
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jhe 0f
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la %r11,\savearea # inside critical section, do cleanup
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bras %r14,cleanup_critical
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tmh %r8,0x0001 # retest problem state after cleanup
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jnz 1f
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0: l %r14,\stack # are we already on the target stack?
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slr %r14,%r15
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sra %r14,\shift
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jnz 1f
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CHECK_STACK 1<<\shift,\savearea
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j 2f
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1: l %r15,\stack # load target stack
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2: ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
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la %r11,STACK_FRAME_OVERHEAD(%r15)
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.endm
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.macro ADD64 high,low,timer
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al \high,\timer
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al \low,\timer+4
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brc 12,.+8
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ahi \high,1
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.endm
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.macro SUB64 high,low,timer
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sl \high,\timer
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sl \low,\timer+4
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brc 3,.+8
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ahi \high,-1
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.endm
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.macro UPDATE_VTIME high,low,enter_timer
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lm \high,\low,__LC_EXIT_TIMER
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SUB64 \high,\low,\enter_timer
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ADD64 \high,\low,__LC_USER_TIMER
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stm \high,\low,__LC_USER_TIMER
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lm \high,\low,__LC_LAST_UPDATE_TIMER
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SUB64 \high,\low,__LC_EXIT_TIMER
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ADD64 \high,\low,__LC_SYSTEM_TIMER
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stm \high,\low,__LC_SYSTEM_TIMER
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mvc __LC_LAST_UPDATE_TIMER(8),\enter_timer
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.endm
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.macro REENABLE_IRQS
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st %r8,__LC_RETURN_PSW
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ni __LC_RETURN_PSW,0xbf
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ssm __LC_RETURN_PSW
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.endm
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.section .kprobes.text, "ax"
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/*
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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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* Returns:
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* gpr2 = prev
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*/
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ENTRY(__switch_to)
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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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jz 0f
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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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0: 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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br %r14
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__critical_start:
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/*
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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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*/
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ENTRY(system_call)
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stpt __LC_SYNC_ENTER_TIMER
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sysc_stm:
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stm %r8,%r15,__LC_SAVE_AREA_SYNC
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l %r12,__LC_THREAD_INFO
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l %r13,__LC_SVC_NEW_PSW+4
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sysc_per:
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l %r15,__LC_KERNEL_STACK
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ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
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la %r11,STACK_FRAME_OVERHEAD(%r15) # pointer to pt_regs
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sysc_vtime:
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UPDATE_VTIME %r8,%r9,__LC_SYNC_ENTER_TIMER
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stm %r0,%r7,__PT_R0(%r11)
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mvc __PT_R8(32,%r11),__LC_SAVE_AREA_SYNC
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mvc __PT_PSW(8,%r11),__LC_SVC_OLD_PSW
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mvc __PT_INT_CODE(4,%r11),__LC_SVC_ILC
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sysc_do_svc:
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oi __TI_flags+3(%r12),_TIF_SYSCALL
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lh %r8,__PT_INT_CODE+2(%r11)
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sla %r8,2 # shift and test for svc0
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jnz sysc_nr_ok
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# svc 0: system call number in %r1
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cl %r1,BASED(.Lnr_syscalls)
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jnl sysc_nr_ok
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sth %r1,__PT_INT_CODE+2(%r11)
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lr %r8,%r1
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sla %r8,2
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sysc_nr_ok:
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l %r10,BASED(.Lsys_call_table) # 31 bit system call table
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xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
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st %r2,__PT_ORIG_GPR2(%r11)
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st %r7,STACK_FRAME_OVERHEAD(%r15)
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l %r9,0(%r8,%r10) # get system call addr.
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tm __TI_flags+2(%r12),_TIF_TRACE >> 8
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jnz sysc_tracesys
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basr %r14,%r9 # call sys_xxxx
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st %r2,__PT_R2(%r11) # store return value
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sysc_return:
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LOCKDEP_SYS_EXIT
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sysc_tif:
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tm __PT_PSW+1(%r11),0x01 # returning to user ?
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jno sysc_restore
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tm __TI_flags+3(%r12),_TIF_WORK_SVC
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jnz sysc_work # check for work
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ni __TI_flags+3(%r12),255-_TIF_SYSCALL
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sysc_restore:
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mvc __LC_RETURN_PSW(8),__PT_PSW(%r11)
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stpt __LC_EXIT_TIMER
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lm %r0,%r15,__PT_R0(%r11)
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lpsw __LC_RETURN_PSW
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sysc_done:
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#
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# One of the work bits is on. Find out which one.
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#
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sysc_work:
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tm __TI_flags+3(%r12),_TIF_MCCK_PENDING
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jo sysc_mcck_pending
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tm __TI_flags+3(%r12),_TIF_NEED_RESCHED
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jo sysc_reschedule
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tm __TI_flags+3(%r12),_TIF_SIGPENDING
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jo sysc_sigpending
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tm __TI_flags+3(%r12),_TIF_NOTIFY_RESUME
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jo sysc_notify_resume
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tm __TI_flags+3(%r12),_TIF_PER_TRAP
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jo sysc_singlestep
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j sysc_return # beware of critical section cleanup
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#
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# _TIF_NEED_RESCHED is set, call schedule
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#
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sysc_reschedule:
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l %r1,BASED(.Lschedule)
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la %r14,BASED(sysc_return)
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br %r1 # call schedule
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#
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# _TIF_MCCK_PENDING is set, call handler
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#
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sysc_mcck_pending:
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l %r1,BASED(.Lhandle_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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#
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# _TIF_SIGPENDING is set, call do_signal
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#
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sysc_sigpending:
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ni __TI_flags+3(%r12),255-_TIF_PER_TRAP # clear TIF_PER_TRAP
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lr %r2,%r11 # pass pointer to 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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jno sysc_return
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lm %r2,%r7,__PT_R2(%r11) # load svc arguments
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xr %r8,%r8 # svc 0 returns -ENOSYS
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clc __PT_INT_CODE+2(2,%r11),BASED(.Lnr_syscalls+2)
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jnl sysc_nr_ok # invalid svc number -> do svc 0
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lh %r8,__PT_INT_CODE+2(%r11) # load new svc number
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sla %r8,2
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j sysc_nr_ok # restart svc
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#
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# _TIF_NOTIFY_RESUME is set, call do_notify_resume
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#
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sysc_notify_resume:
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lr %r2,%r11 # pass pointer to 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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#
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# _TIF_PER_TRAP is set, call do_per_trap
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#
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sysc_singlestep:
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ni __TI_flags+3(%r12),255-(_TIF_SYSCALL | _TIF_PER_TRAP)
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lr %r2,%r11 # pass pointer to pt_regs
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l %r1,BASED(.Ldo_per_trap)
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la %r14,BASED(sysc_return)
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br %r1 # call do_per_trap
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#
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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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#
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sysc_tracesys:
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l %r1,BASED(.Ltrace_enter)
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lr %r2,%r11 # pass pointer to pt_regs
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la %r3,0
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xr %r0,%r0
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icm %r0,3,__PT_INT_CODE+2(%r11)
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st %r0,__PT_R2(%r11)
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basr %r14,%r1 # call do_syscall_trace_enter
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cl %r2,BASED(.Lnr_syscalls)
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jnl sysc_tracenogo
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lr %r8,%r2
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sll %r8,2
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l %r9,0(%r8,%r10)
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sysc_tracego:
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lm %r3,%r7,__PT_R3(%r11)
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st %r7,STACK_FRAME_OVERHEAD(%r15)
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l %r2,__PT_ORIG_GPR2(%r11)
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basr %r14,%r9 # call sys_xxx
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st %r2,__PT_R2(%r11) # store return value
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sysc_tracenogo:
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tm __TI_flags+2(%r12),_TIF_TRACE >> 8
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jz sysc_return
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l %r1,BASED(.Ltrace_exit)
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lr %r2,%r11 # pass pointer to pt_regs
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la %r14,BASED(sysc_return)
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br %r1 # call do_syscall_trace_exit
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#
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# a new process exits the kernel with ret_from_fork
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#
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ENTRY(ret_from_fork)
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la %r11,STACK_FRAME_OVERHEAD(%r15)
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l %r12,__LC_THREAD_INFO
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l %r13,__LC_SVC_NEW_PSW+4
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tm __PT_PSW+1(%r11),0x01 # forking a kernel thread ?
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jo 0f
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st %r15,__PT_R15(%r11) # store stack pointer for new kthread
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0: l %r1,BASED(.Lschedule_tail)
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basr %r14,%r1 # call schedule_tail
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TRACE_IRQS_ON
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ssm __LC_SVC_NEW_PSW # reenable interrupts
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j sysc_tracenogo
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#
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# kernel_execve function needs to deal with pt_regs that is not
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# at the usual place
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#
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ENTRY(kernel_execve)
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stm %r12,%r15,48(%r15)
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lr %r14,%r15
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l %r13,__LC_SVC_NEW_PSW+4
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ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
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st %r14,__SF_BACKCHAIN(%r15)
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la %r12,STACK_FRAME_OVERHEAD(%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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lr %r5,%r12
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basr %r14,%r1 # call do_execve
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ltr %r2,%r2
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je 0f
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ahi %r15,(STACK_FRAME_OVERHEAD + __PT_SIZE)
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lm %r12,%r15,48(%r15)
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br %r14
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# execve succeeded.
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0: ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
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l %r15,__LC_KERNEL_STACK # load ksp
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ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
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la %r11,STACK_FRAME_OVERHEAD(%r15)
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mvc 0(__PT_SIZE,%r11),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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ssm __LC_SVC_NEW_PSW # reenable interrupts
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l %r1,BASED(.Lexecve_tail)
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basr %r14,%r1 # call execve_tail
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j sysc_return
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/*
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* Program check handler routine
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*/
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ENTRY(pgm_check_handler)
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stpt __LC_SYNC_ENTER_TIMER
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stm %r8,%r15,__LC_SAVE_AREA_SYNC
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l %r12,__LC_THREAD_INFO
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l %r13,__LC_SVC_NEW_PSW+4
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lm %r8,%r9,__LC_PGM_OLD_PSW
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tmh %r8,0x0001 # test problem state bit
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jnz 1f # -> fault in user space
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tmh %r8,0x4000 # PER bit set in old PSW ?
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jnz 0f # -> enabled, can't be a double fault
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tm __LC_PGM_ILC+3,0x80 # check for per exception
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jnz pgm_svcper # -> single stepped svc
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0: CHECK_STACK STACK_SIZE,__LC_SAVE_AREA_SYNC
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j 2f
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1: UPDATE_VTIME %r14,%r15,__LC_SYNC_ENTER_TIMER
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l %r15,__LC_KERNEL_STACK
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2: ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
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la %r11,STACK_FRAME_OVERHEAD(%r15)
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stm %r0,%r7,__PT_R0(%r11)
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mvc __PT_R8(32,%r11),__LC_SAVE_AREA_SYNC
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stm %r8,%r9,__PT_PSW(%r11)
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mvc __PT_INT_CODE(4,%r11),__LC_PGM_ILC
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mvc __PT_INT_PARM_LONG(4,%r11),__LC_TRANS_EXC_CODE
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tm __LC_PGM_ILC+3,0x80 # check for per exception
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jz 0f
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l %r1,__TI_task(%r12)
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tmh %r8,0x0001 # kernel per event ?
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jz pgm_kprobe
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oi __TI_flags+3(%r12),_TIF_PER_TRAP
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mvc __THREAD_per_address(4,%r1),__LC_PER_ADDRESS
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mvc __THREAD_per_cause(2,%r1),__LC_PER_CAUSE
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mvc __THREAD_per_paid(1,%r1),__LC_PER_PAID
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0: REENABLE_IRQS
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xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
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l %r1,BASED(.Ljump_table)
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la %r10,0x7f
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n %r10,__PT_INT_CODE(%r11)
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je sysc_return
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sll %r10,2
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l %r1,0(%r10,%r1) # load address of handler routine
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lr %r2,%r11 # pass pointer to pt_regs
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basr %r14,%r1 # branch to interrupt-handler
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j sysc_return
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#
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# PER event in supervisor state, must be kprobes
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#
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pgm_kprobe:
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REENABLE_IRQS
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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)
|
|
ni __LC_RETURN_PSW+1,0xfd # clean wait state bit
|
|
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_CPU_ADDRESS # 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
|
|
|
|
__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
|
|
ni __LC_RETURN_MCCK_PSW+1,0xfd # clear wait state bit
|
|
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
|
|
|
|
/*
|
|
* Restart interruption handler, kick starter for additional CPUs
|
|
*/
|
|
#ifdef CONFIG_SMP
|
|
__CPUINIT
|
|
ENTRY(restart_int_handler)
|
|
basr %r1,0
|
|
restart_base:
|
|
spt restart_vtime-restart_base(%r1)
|
|
stck __LC_LAST_UPDATE_CLOCK
|
|
mvc __LC_LAST_UPDATE_TIMER(8),restart_vtime-restart_base(%r1)
|
|
mvc __LC_EXIT_TIMER(8),restart_vtime-restart_base(%r1)
|
|
l %r15,__LC_GPREGS_SAVE_AREA+60 # load ksp
|
|
lctl %c0,%c15,__LC_CREGS_SAVE_AREA # get new ctl regs
|
|
lam %a0,%a15,__LC_AREGS_SAVE_AREA
|
|
lm %r6,%r15,__SF_GPRS(%r15)# load registers from clone
|
|
l %r1,__LC_THREAD_INFO
|
|
mvc __LC_USER_TIMER(8),__TI_user_timer(%r1)
|
|
mvc __LC_SYSTEM_TIMER(8),__TI_system_timer(%r1)
|
|
xc __LC_STEAL_TIMER(8),__LC_STEAL_TIMER
|
|
ssm __LC_PGM_NEW_PSW # turn dat on, keep irqs off
|
|
basr %r14,0
|
|
l %r14,restart_addr-.(%r14)
|
|
basr %r14,%r14 # call start_secondary
|
|
restart_addr:
|
|
.long start_secondary
|
|
.align 8
|
|
restart_vtime:
|
|
.long 0x7fffffff,0xffffffff
|
|
.previous
|
|
#else
|
|
/*
|
|
* If we do not run with SMP enabled, let the new CPU crash ...
|
|
*/
|
|
ENTRY(restart_int_handler)
|
|
basr %r1,0
|
|
restart_base:
|
|
lpsw restart_crash-restart_base(%r1)
|
|
.align 8
|
|
restart_crash:
|
|
.long 0x000a0000,0x00000000
|
|
restart_go:
|
|
#endif
|
|
|
|
#
|
|
# PSW restart interrupt handler
|
|
#
|
|
ENTRY(psw_restart_int_handler)
|
|
st %r15,__LC_SAVE_AREA_RESTART
|
|
basr %r15,0
|
|
0: l %r15,.Lrestart_stack-0b(%r15) # load restart stack
|
|
l %r15,0(%r15)
|
|
ahi %r15,-__PT_SIZE # create pt_regs on stack
|
|
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
|
|
xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
|
|
basr %r14,0
|
|
1: l %r14,.Ldo_restart-1b(%r14)
|
|
basr %r14,%r14
|
|
basr %r14,0 # load disabled wait PSW if
|
|
2: lpsw restart_psw_crash-2b(%r14) # do_restart returns
|
|
.align 4
|
|
.Ldo_restart:
|
|
.long do_restart
|
|
.Lrestart_stack:
|
|
.long restart_stack
|
|
.align 8
|
|
restart_psw_crash:
|
|
.long 0x000a0000,0x00000000 + restart_psw_crash
|
|
|
|
.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
|
|
|
|
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
|
|
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)
|
|
ni __LC_RETURN_PSW+1,0xfd # clear wait state bit
|
|
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
|
|
|
|
/*
|
|
* Integer constants
|
|
*/
|
|
.align 4
|
|
.Lnr_syscalls: .long NR_syscalls
|
|
|
|
/*
|
|
* 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
|