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-rw-r--r--arch/s390/kernel/entry64.S881
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diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S
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+/*
+ * arch/s390/kernel/entry.S
+ * S390 low-level entry points.
+ *
+ * S390 version
+ * Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
+ * Hartmut Penner (hp@de.ibm.com),
+ * Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
+ */
+
+#include <linux/sys.h>
+#include <linux/linkage.h>
+#include <linux/config.h>
+#include <asm/cache.h>
+#include <asm/lowcore.h>
+#include <asm/errno.h>
+#include <asm/ptrace.h>
+#include <asm/thread_info.h>
+#include <asm/offsets.h>
+#include <asm/unistd.h>
+#include <asm/page.h>
+
+/*
+ * Stack layout for the system_call stack entry.
+ * The first few entries are identical to the user_regs_struct.
+ */
+SP_PTREGS = STACK_FRAME_OVERHEAD
+SP_ARGS = STACK_FRAME_OVERHEAD + __PT_ARGS
+SP_PSW = STACK_FRAME_OVERHEAD + __PT_PSW
+SP_R0 = STACK_FRAME_OVERHEAD + __PT_GPRS
+SP_R1 = STACK_FRAME_OVERHEAD + __PT_GPRS + 8
+SP_R2 = STACK_FRAME_OVERHEAD + __PT_GPRS + 16
+SP_R3 = STACK_FRAME_OVERHEAD + __PT_GPRS + 24
+SP_R4 = STACK_FRAME_OVERHEAD + __PT_GPRS + 32
+SP_R5 = STACK_FRAME_OVERHEAD + __PT_GPRS + 40
+SP_R6 = STACK_FRAME_OVERHEAD + __PT_GPRS + 48
+SP_R7 = STACK_FRAME_OVERHEAD + __PT_GPRS + 56
+SP_R8 = STACK_FRAME_OVERHEAD + __PT_GPRS + 64
+SP_R9 = STACK_FRAME_OVERHEAD + __PT_GPRS + 72
+SP_R10 = STACK_FRAME_OVERHEAD + __PT_GPRS + 80
+SP_R11 = STACK_FRAME_OVERHEAD + __PT_GPRS + 88
+SP_R12 = STACK_FRAME_OVERHEAD + __PT_GPRS + 96
+SP_R13 = STACK_FRAME_OVERHEAD + __PT_GPRS + 104
+SP_R14 = STACK_FRAME_OVERHEAD + __PT_GPRS + 112
+SP_R15 = STACK_FRAME_OVERHEAD + __PT_GPRS + 120
+SP_ORIG_R2 = STACK_FRAME_OVERHEAD + __PT_ORIG_GPR2
+SP_ILC = STACK_FRAME_OVERHEAD + __PT_ILC
+SP_TRAP = STACK_FRAME_OVERHEAD + __PT_TRAP
+SP_SIZE = STACK_FRAME_OVERHEAD + __PT_SIZE
+
+STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
+STACK_SIZE = 1 << STACK_SHIFT
+
+_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
+ _TIF_RESTART_SVC | _TIF_SINGLE_STEP )
+_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NEED_RESCHED)
+
+#define BASED(name) name-system_call(%r13)
+
+ .macro STORE_TIMER lc_offset
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+ stpt \lc_offset
+#endif
+ .endm
+
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+ .macro UPDATE_VTIME lc_from,lc_to,lc_sum
+ lg %r10,\lc_from
+ slg %r10,\lc_to
+ alg %r10,\lc_sum
+ stg %r10,\lc_sum
+ .endm
+#endif
+
+/*
+ * Register usage in interrupt handlers:
+ * R9 - pointer to current task structure
+ * R13 - pointer to literal pool
+ * R14 - return register for function calls
+ * R15 - kernel stack pointer
+ */
+
+ .macro SAVE_ALL_BASE savearea
+ stmg %r12,%r15,\savearea
+ larl %r13,system_call
+ .endm
+
+ .macro SAVE_ALL psworg,savearea,sync
+ la %r12,\psworg
+ .if \sync
+ tm \psworg+1,0x01 # test problem state bit
+ jz 2f # skip stack setup save
+ lg %r15,__LC_KERNEL_STACK # problem state -> load ksp
+ .else
+ tm \psworg+1,0x01 # test problem state bit
+ jnz 1f # from user -> load kernel stack
+ clc \psworg+8(8),BASED(.Lcritical_end)
+ jhe 0f
+ clc \psworg+8(8),BASED(.Lcritical_start)
+ jl 0f
+ brasl %r14,cleanup_critical
+ tm 0(%r12),0x01 # retest problem state after cleanup
+ jnz 1f
+0: lg %r14,__LC_ASYNC_STACK # are we already on the async. stack ?
+ slgr %r14,%r15
+ srag %r14,%r14,STACK_SHIFT
+ jz 2f
+1: lg %r15,__LC_ASYNC_STACK # load async stack
+ .endif
+#ifdef CONFIG_CHECK_STACK
+ j 3f
+2: tml %r15,STACK_SIZE - CONFIG_STACK_GUARD
+ jz stack_overflow
+3:
+#endif
+2: aghi %r15,-SP_SIZE # make room for registers & psw
+ mvc SP_PSW(16,%r15),0(%r12) # move user PSW to stack
+ la %r12,\psworg
+ stg %r2,SP_ORIG_R2(%r15) # store original content of gpr 2
+ icm %r12,12,__LC_SVC_ILC
+ stmg %r0,%r11,SP_R0(%r15) # store gprs %r0-%r11 to kernel stack
+ st %r12,SP_ILC(%r15)
+ mvc SP_R12(32,%r15),\savearea # move %r12-%r15 to stack
+ la %r12,0
+ stg %r12,__SF_BACKCHAIN(%r15)
+ .endm
+
+ .macro RESTORE_ALL sync
+ mvc __LC_RETURN_PSW(16),SP_PSW(%r15) # move user PSW to lowcore
+ .if !\sync
+ ni __LC_RETURN_PSW+1,0xfd # clear wait state bit
+ .endif
+ lmg %r0,%r15,SP_R0(%r15) # load gprs 0-15 of user
+ STORE_TIMER __LC_EXIT_TIMER
+ lpswe __LC_RETURN_PSW # back to caller
+ .endm
+
+/*
+ * Scheduler resume function, called by switch_to
+ * gpr2 = (task_struct *) prev
+ * gpr3 = (task_struct *) next
+ * Returns:
+ * gpr2 = prev
+ */
+ .globl __switch_to
+__switch_to:
+ tm __THREAD_per+4(%r3),0xe8 # is the new process using per ?
+ jz __switch_to_noper # if not we're fine
+ stctg %c9,%c11,__SF_EMPTY(%r15)# We are using per stuff
+ clc __THREAD_per(24,%r3),__SF_EMPTY(%r15)
+ je __switch_to_noper # we got away without bashing TLB's
+ lctlg %c9,%c11,__THREAD_per(%r3) # Nope we didn't
+__switch_to_noper:
+ stmg %r6,%r15,__SF_GPRS(%r15)# store __switch_to registers of prev task
+ stg %r15,__THREAD_ksp(%r2) # store kernel stack to prev->tss.ksp
+ lg %r15,__THREAD_ksp(%r3) # load kernel stack from next->tss.ksp
+ lmg %r6,%r15,__SF_GPRS(%r15)# load __switch_to registers of next task
+ stg %r3,__LC_CURRENT # __LC_CURRENT = current task struct
+ lctl %c4,%c4,__TASK_pid(%r3) # load pid to control reg. 4
+ lg %r3,__THREAD_info(%r3) # load thread_info from task struct
+ stg %r3,__LC_THREAD_INFO
+ aghi %r3,STACK_SIZE
+ stg %r3,__LC_KERNEL_STACK # __LC_KERNEL_STACK = new kernel stack
+ br %r14
+
+__critical_start:
+/*
+ * SVC interrupt handler routine. System calls are synchronous events and
+ * are executed with interrupts enabled.
+ */
+
+ .globl system_call
+system_call:
+ STORE_TIMER __LC_SYNC_ENTER_TIMER
+sysc_saveall:
+ SAVE_ALL_BASE __LC_SAVE_AREA
+ SAVE_ALL __LC_SVC_OLD_PSW,__LC_SAVE_AREA,1
+ llgh %r7,__LC_SVC_INT_CODE # get svc number from lowcore
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+sysc_vtime:
+ tm SP_PSW+1(%r15),0x01 # interrupting from user ?
+ jz sysc_do_svc
+ UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
+sysc_stime:
+ UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
+sysc_update:
+ mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
+#endif
+sysc_do_svc:
+ lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
+ slag %r7,%r7,2 # *4 and test for svc 0
+ jnz sysc_nr_ok
+ # svc 0: system call number in %r1
+ cl %r1,BASED(.Lnr_syscalls)
+ jnl sysc_nr_ok
+ lgfr %r7,%r1 # clear high word in r1
+ slag %r7,%r7,2 # svc 0: system call number in %r1
+sysc_nr_ok:
+ mvc SP_ARGS(8,%r15),SP_R7(%r15)
+sysc_do_restart:
+ larl %r10,sys_call_table
+#ifdef CONFIG_S390_SUPPORT
+ tm SP_PSW+3(%r15),0x01 # are we running in 31 bit mode ?
+ jo sysc_noemu
+ larl %r10,sys_call_table_emu # use 31 bit emulation system calls
+sysc_noemu:
+#endif
+ tm __TI_flags+7(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
+ lgf %r8,0(%r7,%r10) # load address of system call routine
+ jnz sysc_tracesys
+ basr %r14,%r8 # call sys_xxxx
+ stg %r2,SP_R2(%r15) # store return value (change R2 on stack)
+ # ATTENTION: check sys_execve_glue before
+ # changing anything here !!
+
+sysc_return:
+ tm SP_PSW+1(%r15),0x01 # returning to user ?
+ jno sysc_leave
+ tm __TI_flags+7(%r9),_TIF_WORK_SVC
+ jnz sysc_work # there is work to do (signals etc.)
+sysc_leave:
+ RESTORE_ALL 1
+
+#
+# recheck if there is more work to do
+#
+sysc_work_loop:
+ tm __TI_flags+7(%r9),_TIF_WORK_SVC
+ jz sysc_leave # there is no work to do
+#
+# One of the work bits is on. Find out which one.
+#
+sysc_work:
+ tm __TI_flags+7(%r9),_TIF_NEED_RESCHED
+ jo sysc_reschedule
+ tm __TI_flags+7(%r9),_TIF_SIGPENDING
+ jo sysc_sigpending
+ tm __TI_flags+7(%r9),_TIF_RESTART_SVC
+ jo sysc_restart
+ tm __TI_flags+7(%r9),_TIF_SINGLE_STEP
+ jo sysc_singlestep
+ j sysc_leave
+
+#
+# _TIF_NEED_RESCHED is set, call schedule
+#
+sysc_reschedule:
+ larl %r14,sysc_work_loop
+ jg schedule # return point is sysc_return
+
+#
+# _TIF_SIGPENDING is set, call do_signal
+#
+sysc_sigpending:
+ ni __TI_flags+7(%r9),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
+ la %r2,SP_PTREGS(%r15) # load pt_regs
+ sgr %r3,%r3 # clear *oldset
+ brasl %r14,do_signal # call do_signal
+ tm __TI_flags+7(%r9),_TIF_RESTART_SVC
+ jo sysc_restart
+ tm __TI_flags+7(%r9),_TIF_SINGLE_STEP
+ jo sysc_singlestep
+ j sysc_leave # out of here, do NOT recheck
+
+#
+# _TIF_RESTART_SVC is set, set up registers and restart svc
+#
+sysc_restart:
+ ni __TI_flags+7(%r9),255-_TIF_RESTART_SVC # clear TIF_RESTART_SVC
+ lg %r7,SP_R2(%r15) # load new svc number
+ slag %r7,%r7,2 # *4
+ mvc SP_R2(8,%r15),SP_ORIG_R2(%r15) # restore first argument
+ lmg %r2,%r6,SP_R2(%r15) # load svc arguments
+ j sysc_do_restart # restart svc
+
+#
+# _TIF_SINGLE_STEP is set, call do_single_step
+#
+sysc_singlestep:
+ ni __TI_flags+7(%r9),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
+ lhi %r0,__LC_PGM_OLD_PSW
+ sth %r0,SP_TRAP(%r15) # set trap indication to pgm check
+ la %r2,SP_PTREGS(%r15) # address of register-save area
+ larl %r14,sysc_return # load adr. of system return
+ jg do_single_step # branch to do_sigtrap
+
+
+__critical_end:
+
+#
+# call syscall_trace before and after system call
+# special linkage: %r12 contains the return address for trace_svc
+#
+sysc_tracesys:
+ la %r2,SP_PTREGS(%r15) # load pt_regs
+ la %r3,0
+ srl %r7,2
+ stg %r7,SP_R2(%r15)
+ brasl %r14,syscall_trace
+ lghi %r0,NR_syscalls
+ clg %r0,SP_R2(%r15)
+ jnh sysc_tracenogo
+ lg %r7,SP_R2(%r15) # strace might have changed the
+ sll %r7,2 # system call
+ lgf %r8,0(%r7,%r10)
+sysc_tracego:
+ lmg %r3,%r6,SP_R3(%r15)
+ lg %r2,SP_ORIG_R2(%r15)
+ basr %r14,%r8 # call sys_xxx
+ stg %r2,SP_R2(%r15) # store return value
+sysc_tracenogo:
+ tm __TI_flags+7(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
+ jz sysc_return
+ la %r2,SP_PTREGS(%r15) # load pt_regs
+ la %r3,1
+ larl %r14,sysc_return # return point is sysc_return
+ jg syscall_trace
+
+#
+# a new process exits the kernel with ret_from_fork
+#
+ .globl ret_from_fork
+ret_from_fork:
+ lg %r13,__LC_SVC_NEW_PSW+8
+ lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
+ tm SP_PSW+1(%r15),0x01 # forking a kernel thread ?
+ jo 0f
+ stg %r15,SP_R15(%r15) # store stack pointer for new kthread
+0: brasl %r14,schedule_tail
+ stosm 24(%r15),0x03 # reenable interrupts
+ j sysc_return
+
+#
+# clone, fork, vfork, exec and sigreturn need glue,
+# because they all expect pt_regs as parameter,
+# but are called with different parameter.
+# return-address is set up above
+#
+sys_clone_glue:
+ la %r2,SP_PTREGS(%r15) # load pt_regs
+ jg sys_clone # branch to sys_clone
+
+#ifdef CONFIG_S390_SUPPORT
+sys32_clone_glue:
+ la %r2,SP_PTREGS(%r15) # load pt_regs
+ jg sys32_clone # branch to sys32_clone
+#endif
+
+sys_fork_glue:
+ la %r2,SP_PTREGS(%r15) # load pt_regs
+ jg sys_fork # branch to sys_fork
+
+sys_vfork_glue:
+ la %r2,SP_PTREGS(%r15) # load pt_regs
+ jg sys_vfork # branch to sys_vfork
+
+sys_execve_glue:
+ la %r2,SP_PTREGS(%r15) # load pt_regs
+ lgr %r12,%r14 # save return address
+ brasl %r14,sys_execve # call sys_execve
+ ltgr %r2,%r2 # check if execve failed
+ bnz 0(%r12) # it did fail -> store result in gpr2
+ b 6(%r12) # SKIP STG 2,SP_R2(15) in
+ # system_call/sysc_tracesys
+#ifdef CONFIG_S390_SUPPORT
+sys32_execve_glue:
+ la %r2,SP_PTREGS(%r15) # load pt_regs
+ lgr %r12,%r14 # save return address
+ brasl %r14,sys32_execve # call sys32_execve
+ ltgr %r2,%r2 # check if execve failed
+ bnz 0(%r12) # it did fail -> store result in gpr2
+ b 6(%r12) # SKIP STG 2,SP_R2(15) in
+ # system_call/sysc_tracesys
+#endif
+
+sys_sigreturn_glue:
+ la %r2,SP_PTREGS(%r15) # load pt_regs as parameter
+ jg sys_sigreturn # branch to sys_sigreturn
+
+#ifdef CONFIG_S390_SUPPORT
+sys32_sigreturn_glue:
+ la %r2,SP_PTREGS(%r15) # load pt_regs as parameter
+ jg sys32_sigreturn # branch to sys32_sigreturn
+#endif
+
+sys_rt_sigreturn_glue:
+ la %r2,SP_PTREGS(%r15) # load pt_regs as parameter
+ jg sys_rt_sigreturn # branch to sys_sigreturn
+
+#ifdef CONFIG_S390_SUPPORT
+sys32_rt_sigreturn_glue:
+ la %r2,SP_PTREGS(%r15) # load pt_regs as parameter
+ jg sys32_rt_sigreturn # branch to sys32_sigreturn
+#endif
+
+#
+# sigsuspend and rt_sigsuspend need pt_regs as an additional
+# parameter and they have to skip the store of %r2 into the
+# user register %r2 because the return value was set in
+# sigsuspend and rt_sigsuspend already and must not be overwritten!
+#
+
+sys_sigsuspend_glue:
+ lgr %r5,%r4 # move mask back
+ lgr %r4,%r3 # move history1 parameter
+ lgr %r3,%r2 # move history0 parameter
+ la %r2,SP_PTREGS(%r15) # load pt_regs as first parameter
+ la %r14,6(%r14) # skip store of return value
+ jg sys_sigsuspend # branch to sys_sigsuspend
+
+#ifdef CONFIG_S390_SUPPORT
+sys32_sigsuspend_glue:
+ llgfr %r4,%r4 # unsigned long
+ lgr %r5,%r4 # move mask back
+ lgfr %r3,%r3 # int
+ lgr %r4,%r3 # move history1 parameter
+ lgfr %r2,%r2 # int
+ lgr %r3,%r2 # move history0 parameter
+ la %r2,SP_PTREGS(%r15) # load pt_regs as first parameter
+ la %r14,6(%r14) # skip store of return value
+ jg sys32_sigsuspend # branch to sys32_sigsuspend
+#endif
+
+sys_rt_sigsuspend_glue:
+ lgr %r4,%r3 # move sigsetsize parameter
+ lgr %r3,%r2 # move unewset parameter
+ la %r2,SP_PTREGS(%r15) # load pt_regs as first parameter
+ la %r14,6(%r14) # skip store of return value
+ jg sys_rt_sigsuspend # branch to sys_rt_sigsuspend
+
+#ifdef CONFIG_S390_SUPPORT
+sys32_rt_sigsuspend_glue:
+ llgfr %r3,%r3 # size_t
+ lgr %r4,%r3 # move sigsetsize parameter
+ llgtr %r2,%r2 # sigset_emu31_t *
+ lgr %r3,%r2 # move unewset parameter
+ la %r2,SP_PTREGS(%r15) # load pt_regs as first parameter
+ la %r14,6(%r14) # skip store of return value
+ jg sys32_rt_sigsuspend # branch to sys32_rt_sigsuspend
+#endif
+
+sys_sigaltstack_glue:
+ la %r4,SP_PTREGS(%r15) # load pt_regs as parameter
+ jg sys_sigaltstack # branch to sys_sigreturn
+
+#ifdef CONFIG_S390_SUPPORT
+sys32_sigaltstack_glue:
+ la %r4,SP_PTREGS(%r15) # load pt_regs as parameter
+ jg sys32_sigaltstack_wrapper # branch to sys_sigreturn
+#endif
+
+/*
+ * Program check handler routine
+ */
+
+ .globl pgm_check_handler
+pgm_check_handler:
+/*
+ * First we need to check for a special case:
+ * Single stepping an instruction that disables the PER event mask will
+ * cause a PER event AFTER the mask has been set. Example: SVC or LPSW.
+ * For a single stepped SVC the program check handler gets control after
+ * the SVC new PSW has been loaded. But we want to execute the SVC first and
+ * then handle the PER event. Therefore we update the SVC old PSW to point
+ * to the pgm_check_handler and branch to the SVC handler after we checked
+ * if we have to load the kernel stack register.
+ * For every other possible cause for PER event without the PER mask set
+ * we just ignore the PER event (FIXME: is there anything we have to do
+ * for LPSW?).
+ */
+ STORE_TIMER __LC_SYNC_ENTER_TIMER
+ SAVE_ALL_BASE __LC_SAVE_AREA
+ tm __LC_PGM_INT_CODE+1,0x80 # check whether we got a per exception
+ jnz pgm_per # got per exception -> special case
+ SAVE_ALL __LC_PGM_OLD_PSW,__LC_SAVE_AREA,1
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+ tm SP_PSW+1(%r15),0x01 # interrupting from user ?
+ jz pgm_no_vtime
+ UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
+ UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
+ mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
+pgm_no_vtime:
+#endif
+ lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
+ lgf %r3,__LC_PGM_ILC # load program interruption code
+ lghi %r8,0x7f
+ ngr %r8,%r3
+pgm_do_call:
+ sll %r8,3
+ larl %r1,pgm_check_table
+ lg %r1,0(%r8,%r1) # load address of handler routine
+ la %r2,SP_PTREGS(%r15) # address of register-save area
+ larl %r14,sysc_return
+ br %r1 # branch to interrupt-handler
+
+#
+# handle per exception
+#
+pgm_per:
+ tm __LC_PGM_OLD_PSW,0x40 # test if per event recording is on
+ jnz pgm_per_std # ok, normal per event from user space
+# ok its one of the special cases, now we need to find out which one
+ clc __LC_PGM_OLD_PSW(16),__LC_SVC_NEW_PSW
+ je pgm_svcper
+# no interesting special case, ignore PER event
+ lmg %r12,%r15,__LC_SAVE_AREA
+ lpswe __LC_PGM_OLD_PSW
+
+#
+# Normal per exception
+#
+pgm_per_std:
+ SAVE_ALL __LC_PGM_OLD_PSW,__LC_SAVE_AREA,1
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+ tm SP_PSW+1(%r15),0x01 # interrupting from user ?
+ jz pgm_no_vtime2
+ UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
+ UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
+ mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
+pgm_no_vtime2:
+#endif
+ lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
+ lg %r1,__TI_task(%r9)
+ mvc __THREAD_per+__PER_atmid(2,%r1),__LC_PER_ATMID
+ mvc __THREAD_per+__PER_address(8,%r1),__LC_PER_ADDRESS
+ mvc __THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID
+ oi __TI_flags+7(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
+ lgf %r3,__LC_PGM_ILC # load program interruption code
+ lghi %r8,0x7f
+ ngr %r8,%r3 # clear per-event-bit and ilc
+ je sysc_return
+ j pgm_do_call
+
+#
+# it was a single stepped SVC that is causing all the trouble
+#
+pgm_svcper:
+ SAVE_ALL __LC_SVC_OLD_PSW,__LC_SAVE_AREA,1
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+ tm SP_PSW+1(%r15),0x01 # interrupting from user ?
+ jz pgm_no_vtime3
+ UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
+ UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
+ mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
+pgm_no_vtime3:
+#endif
+ llgh %r7,__LC_SVC_INT_CODE # get svc number from lowcore
+ lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
+ lg %r1,__TI_task(%r9)
+ mvc __THREAD_per+__PER_atmid(2,%r1),__LC_PER_ATMID
+ mvc __THREAD_per+__PER_address(8,%r1),__LC_PER_ADDRESS
+ mvc __THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID
+ oi __TI_flags+7(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
+ stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
+ j sysc_do_svc
+
+/*
+ * IO interrupt handler routine
+ */
+ .globl io_int_handler
+io_int_handler:
+ STORE_TIMER __LC_ASYNC_ENTER_TIMER
+ stck __LC_INT_CLOCK
+ SAVE_ALL_BASE __LC_SAVE_AREA+32
+ SAVE_ALL __LC_IO_OLD_PSW,__LC_SAVE_AREA+32,0
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+ tm SP_PSW+1(%r15),0x01 # interrupting from user ?
+ jz io_no_vtime
+ UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
+ UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
+ mvc __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
+io_no_vtime:
+#endif
+ lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
+ la %r2,SP_PTREGS(%r15) # address of register-save area
+ brasl %r14,do_IRQ # call standard irq handler
+
+io_return:
+ tm SP_PSW+1(%r15),0x01 # returning to user ?
+#ifdef CONFIG_PREEMPT
+ jno io_preempt # no -> check for preemptive scheduling
+#else
+ jno io_leave # no-> skip resched & signal
+#endif
+ tm __TI_flags+7(%r9),_TIF_WORK_INT
+ jnz io_work # there is work to do (signals etc.)
+io_leave:
+ RESTORE_ALL 0
+
+#ifdef CONFIG_PREEMPT
+io_preempt:
+ icm %r0,15,__TI_precount(%r9)
+ jnz io_leave
+ # switch to kernel stack
+ lg %r1,SP_R15(%r15)
+ aghi %r1,-SP_SIZE
+ mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
+ xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1) # clear back chain
+ lgr %r15,%r1
+io_resume_loop:
+ tm __TI_flags+7(%r9),_TIF_NEED_RESCHED
+ jno io_leave
+ larl %r1,.Lc_pactive
+ mvc __TI_precount(4,%r9),0(%r1)
+ stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
+ brasl %r14,schedule # call schedule
+ stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
+ xc __TI_precount(4,%r9),__TI_precount(%r9)
+ j io_resume_loop
+#endif
+
+#
+# switch to kernel stack, then check TIF bits
+#
+io_work:
+ lg %r1,__LC_KERNEL_STACK
+ aghi %r1,-SP_SIZE
+ mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
+ xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1) # clear back chain
+ lgr %r15,%r1
+#
+# One of the work bits is on. Find out which one.
+# Checked are: _TIF_SIGPENDING and _TIF_NEED_RESCHED
+#
+io_work_loop:
+ tm __TI_flags+7(%r9),_TIF_NEED_RESCHED
+ jo io_reschedule
+ tm __TI_flags+7(%r9),_TIF_SIGPENDING
+ jo io_sigpending
+ j io_leave
+
+#
+# _TIF_NEED_RESCHED is set, call schedule
+#
+io_reschedule:
+ stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
+ brasl %r14,schedule # call scheduler
+ stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
+ tm __TI_flags+7(%r9),_TIF_WORK_INT
+ jz io_leave # there is no work to do
+ j io_work_loop
+
+#
+# _TIF_SIGPENDING is set, call do_signal
+#
+io_sigpending:
+ stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
+ la %r2,SP_PTREGS(%r15) # load pt_regs
+ slgr %r3,%r3 # clear *oldset
+ brasl %r14,do_signal # call do_signal
+ stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
+ j sysc_leave # out of here, do NOT recheck
+
+/*
+ * External interrupt handler routine
+ */
+ .globl ext_int_handler
+ext_int_handler:
+ STORE_TIMER __LC_ASYNC_ENTER_TIMER
+ stck __LC_INT_CLOCK
+ SAVE_ALL_BASE __LC_SAVE_AREA+32
+ SAVE_ALL __LC_EXT_OLD_PSW,__LC_SAVE_AREA+32,0
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+ tm SP_PSW+1(%r15),0x01 # interrupting from user ?
+ jz ext_no_vtime
+ UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
+ UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
+ mvc __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
+ext_no_vtime:
+#endif
+ lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
+ la %r2,SP_PTREGS(%r15) # address of register-save area
+ llgh %r3,__LC_EXT_INT_CODE # get interruption code
+ brasl %r14,do_extint
+ j io_return
+
+/*
+ * Machine check handler routines
+ */
+ .globl mcck_int_handler
+mcck_int_handler:
+ STORE_TIMER __LC_ASYNC_ENTER_TIMER
+ SAVE_ALL_BASE __LC_SAVE_AREA+64
+ SAVE_ALL __LC_MCK_OLD_PSW,__LC_SAVE_AREA+64,0
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+ tm SP_PSW+1(%r15),0x01 # interrupting from user ?
+ jz mcck_no_vtime
+ UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
+ UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
+ mvc __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
+mcck_no_vtime:
+#endif
+ brasl %r14,s390_do_machine_check
+mcck_return:
+ RESTORE_ALL 0
+
+#ifdef CONFIG_SMP
+/*
+ * Restart interruption handler, kick starter for additional CPUs
+ */
+ .globl restart_int_handler
+restart_int_handler:
+ lg %r15,__LC_SAVE_AREA+120 # load ksp
+ lghi %r10,__LC_CREGS_SAVE_AREA
+ lctlg %c0,%c15,0(%r10) # get new ctl regs
+ lghi %r10,__LC_AREGS_SAVE_AREA
+ lam %a0,%a15,0(%r10)
+ lmg %r6,%r15,__SF_GPRS(%r15) # load registers from clone
+ stosm __SF_EMPTY(%r15),0x04 # now we can turn dat on
+ jg start_secondary
+#else
+/*
+ * If we do not run with SMP enabled, let the new CPU crash ...
+ */
+ .globl restart_int_handler
+restart_int_handler:
+ basr %r1,0
+restart_base:
+ lpswe restart_crash-restart_base(%r1)
+ .align 8
+restart_crash:
+ .long 0x000a0000,0x00000000,0x00000000,0x00000000
+restart_go:
+#endif
+
+#ifdef CONFIG_CHECK_STACK
+/*
+ * The synchronous or the asynchronous stack overflowed. We are dead.
+ * No need to properly save the registers, we are going to panic anyway.
+ * Setup a pt_regs so that show_trace can provide a good call trace.
+ */
+stack_overflow:
+ lg %r15,__LC_PANIC_STACK # change to panic stack
+ aghi %r1,-SP_SIZE
+ mvc SP_PSW(16,%r15),0(%r12) # move user PSW to stack
+ stmg %r0,%r11,SP_R0(%r15) # store gprs %r0-%r11 to kernel stack
+ la %r1,__LC_SAVE_AREA
+ chi %r12,__LC_SVC_OLD_PSW
+ je 0f
+ chi %r12,__LC_PGM_OLD_PSW
+ je 0f
+ la %r1,__LC_SAVE_AREA+16
+0: mvc SP_R12(32,%r15),0(%r1) # move %r12-%r15 to stack
+ xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15) # clear back chain
+ la %r2,SP_PTREGS(%r15) # load pt_regs
+ jg kernel_stack_overflow
+#endif
+
+cleanup_table_system_call:
+ .quad system_call, sysc_do_svc
+cleanup_table_sysc_return:
+ .quad sysc_return, sysc_leave
+cleanup_table_sysc_leave:
+ .quad sysc_leave, sysc_work_loop
+cleanup_table_sysc_work_loop:
+ .quad sysc_work_loop, sysc_reschedule
+
+cleanup_critical:
+ clc 8(8,%r12),BASED(cleanup_table_system_call)
+ jl 0f
+ clc 8(8,%r12),BASED(cleanup_table_system_call+8)
+ jl cleanup_system_call
+0:
+ clc 8(8,%r12),BASED(cleanup_table_sysc_return)
+ jl 0f
+ clc 8(8,%r12),BASED(cleanup_table_sysc_return+8)
+ jl cleanup_sysc_return
+0:
+ clc 8(8,%r12),BASED(cleanup_table_sysc_leave)
+ jl 0f
+ clc 8(8,%r12),BASED(cleanup_table_sysc_leave+8)
+ jl cleanup_sysc_leave
+0:
+ clc 8(8,%r12),BASED(cleanup_table_sysc_work_loop)
+ jl 0f
+ clc 8(8,%r12),BASED(cleanup_table_sysc_work_loop+8)
+ jl cleanup_sysc_leave
+0:
+ br %r14
+
+cleanup_system_call:
+ mvc __LC_RETURN_PSW(16),0(%r12)
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+ clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn+8)
+ jh 0f
+ mvc __LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER
+0: clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn+16)
+ jhe cleanup_vtime
+#endif
+ clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn)
+ jh 0f
+ mvc __LC_SAVE_AREA(32),__LC_SAVE_AREA+32
+0: stg %r13,__LC_SAVE_AREA+40
+ SAVE_ALL __LC_SVC_OLD_PSW,__LC_SAVE_AREA,1
+ stg %r15,__LC_SAVE_AREA+56
+ llgh %r7,__LC_SVC_INT_CODE
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+cleanup_vtime:
+ clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn+24)
+ jhe cleanup_stime
+ tm SP_PSW+1(%r15),0x01 # interrupting from user ?
+ jz cleanup_novtime
+ UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
+cleanup_stime:
+ clc __LC_RETURN_PSW+8(8),BASED(cleanup_system_call_insn+32)
+ jh cleanup_update
+ UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
+cleanup_update:
+ mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
+cleanup_novtime:
+#endif
+ mvc __LC_RETURN_PSW+8(8),BASED(cleanup_table_system_call+8)
+ la %r12,__LC_RETURN_PSW
+ br %r14
+cleanup_system_call_insn:
+ .quad sysc_saveall
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+ .quad system_call
+ .quad sysc_vtime
+ .quad sysc_stime
+ .quad sysc_update
+#endif
+
+cleanup_sysc_return:
+ mvc __LC_RETURN_PSW(8),0(%r12)
+ mvc __LC_RETURN_PSW+8(8),BASED(cleanup_table_sysc_return)
+ la %r12,__LC_RETURN_PSW
+ br %r14
+
+cleanup_sysc_leave:
+ clc 8(8,%r12),BASED(cleanup_sysc_leave_insn)
+ je 0f
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+ mvc __LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER
+ clc 8(8,%r12),BASED(cleanup_sysc_leave_insn+8)
+ je 0f
+#endif
+ mvc __LC_RETURN_PSW(16),SP_PSW(%r15)
+ mvc __LC_SAVE_AREA+32(32),SP_R12(%r15)
+ lmg %r0,%r11,SP_R0(%r15)
+ lg %r15,SP_R15(%r15)
+0: la %r12,__LC_RETURN_PSW
+ br %r14
+cleanup_sysc_leave_insn:
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+ .quad sysc_leave + 16
+#endif
+ .quad sysc_leave + 12
+
+/*
+ * Integer constants
+ */
+ .align 4
+.Lconst:
+.Lc_pactive: .long PREEMPT_ACTIVE
+.Lnr_syscalls: .long NR_syscalls
+.L0x0130: .short 0x130
+.L0x0140: .short 0x140
+.L0x0150: .short 0x150
+.L0x0160: .short 0x160
+.L0x0170: .short 0x170
+.Lcritical_start:
+ .quad __critical_start
+.Lcritical_end:
+ .quad __critical_end
+
+#define SYSCALL(esa,esame,emu) .long esame
+ .globl sys_call_table
+sys_call_table:
+#include "syscalls.S"
+#undef SYSCALL
+
+#ifdef CONFIG_S390_SUPPORT
+
+#define SYSCALL(esa,esame,emu) .long emu
+ .globl sys_call_table_emu
+sys_call_table_emu:
+#include "syscalls.S"
+#undef SYSCALL
+#endif