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linux/arch/s390/kernel/entry.S
Heiko Carstens 77fa22450d [PATCH] s390: improved machine check handling
Improved machine check handling.  Kernel is now able to receive machine checks
while in kernel mode (system call, interrupt and program check handling).
Also register validation is now performed.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25 16:24:37 -07:00

953 lines
31 KiB
ArmAsm

/*
* 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),
* Heiko Carstens <heiko.carstens@de.ibm.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 + 4
SP_R2 = STACK_FRAME_OVERHEAD + __PT_GPRS + 8
SP_R3 = STACK_FRAME_OVERHEAD + __PT_GPRS + 12
SP_R4 = STACK_FRAME_OVERHEAD + __PT_GPRS + 16
SP_R5 = STACK_FRAME_OVERHEAD + __PT_GPRS + 20
SP_R6 = STACK_FRAME_OVERHEAD + __PT_GPRS + 24
SP_R7 = STACK_FRAME_OVERHEAD + __PT_GPRS + 28
SP_R8 = STACK_FRAME_OVERHEAD + __PT_GPRS + 32
SP_R9 = STACK_FRAME_OVERHEAD + __PT_GPRS + 36
SP_R10 = STACK_FRAME_OVERHEAD + __PT_GPRS + 40
SP_R11 = STACK_FRAME_OVERHEAD + __PT_GPRS + 44
SP_R12 = STACK_FRAME_OVERHEAD + __PT_GPRS + 48
SP_R13 = STACK_FRAME_OVERHEAD + __PT_GPRS + 52
SP_R14 = STACK_FRAME_OVERHEAD + __PT_GPRS + 56
SP_R15 = STACK_FRAME_OVERHEAD + __PT_GPRS + 60
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
_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NEED_RESCHED | _TIF_MCCK_PENDING | \
_TIF_RESTART_SVC | _TIF_SINGLE_STEP )
_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NEED_RESCHED | _TIF_MCCK_PENDING)
STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
STACK_SIZE = 1 << STACK_SHIFT
#define BASED(name) name-system_call(%r13)
/*
* 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 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
lm %r10,%r11,\lc_from
sl %r10,\lc_to
sl %r11,\lc_to+4
bc 3,BASED(0f)
sl %r10,BASED(.Lc_1)
0: al %r10,\lc_sum
al %r11,\lc_sum+4
bc 12,BASED(1f)
al %r10,BASED(.Lc_1)
1: stm %r10,%r11,\lc_sum
.endm
#endif
.macro SAVE_ALL_BASE savearea
stm %r12,%r15,\savearea
l %r13,__LC_SVC_NEW_PSW+4 # load &system_call to %r13
.endm
.macro SAVE_ALL psworg,savearea,sync
la %r12,\psworg
.if \sync
tm \psworg+1,0x01 # test problem state bit
bz BASED(2f) # skip stack setup save
l %r15,__LC_KERNEL_STACK # problem state -> load ksp
.else
tm \psworg+1,0x01 # test problem state bit
bnz BASED(1f) # from user -> load async stack
clc \psworg+4(4),BASED(.Lcritical_end)
bhe BASED(0f)
clc \psworg+4(4),BASED(.Lcritical_start)
bl BASED(0f)
l %r14,BASED(.Lcleanup_critical)
basr %r14,%r14
tm 0(%r12),0x01 # retest problem state after cleanup
bnz BASED(1f)
0: l %r14,__LC_ASYNC_STACK # are we already on the async stack ?
slr %r14,%r15
sra %r14,STACK_SHIFT
be BASED(2f)
1: l %r15,__LC_ASYNC_STACK
.endif
#ifdef CONFIG_CHECK_STACK
b BASED(3f)
2: tml %r15,STACK_SIZE - CONFIG_STACK_GUARD
bz BASED(stack_overflow)
3:
#endif
2:
.endm
.macro CREATE_STACK_FRAME psworg,savearea
s %r15,BASED(.Lc_spsize) # make room for registers & psw
mvc SP_PSW(8,%r15),0(%r12) # move user PSW to stack
la %r12,\psworg
st %r2,SP_ORIG_R2(%r15) # store original content of gpr 2
icm %r12,12,__LC_SVC_ILC
stm %r0,%r11,SP_R0(%r15) # store gprs %r0-%r11 to kernel stack
st %r12,SP_ILC(%r15)
mvc SP_R12(16,%r15),\savearea # move %r12-%r15 to stack
la %r12,0
st %r12,__SF_BACKCHAIN(%r15) # clear back chain
.endm
.macro RESTORE_ALL sync
mvc __LC_RETURN_PSW(8),SP_PSW(%r15) # move user PSW to lowcore
.if !\sync
ni __LC_RETURN_PSW+1,0xfd # clear wait state bit
.endif
lm %r0,%r15,SP_R0(%r15) # load gprs 0-15 of user
STORE_TIMER __LC_EXIT_TIMER
lpsw __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:
basr %r1,0
__switch_to_base:
tm __THREAD_per(%r3),0xe8 # new process is using per ?
bz __switch_to_noper-__switch_to_base(%r1) # if not we're fine
stctl %c9,%c11,__SF_EMPTY(%r15) # We are using per stuff
clc __THREAD_per(12,%r3),__SF_EMPTY(%r15)
be __switch_to_noper-__switch_to_base(%r1) # we got away w/o bashing TLB's
lctl %c9,%c11,__THREAD_per(%r3) # Nope we didn't
__switch_to_noper:
l %r4,__THREAD_info(%r2) # get thread_info of prev
tm __TI_flags+3(%r4),_TIF_MCCK_PENDING # machine check pending?
bz __switch_to_no_mcck-__switch_to_base(%r1)
ni __TI_flags+3(%r4),255-_TIF_MCCK_PENDING # clear flag in prev
l %r4,__THREAD_info(%r3) # get thread_info of next
oi __TI_flags+3(%r4),_TIF_MCCK_PENDING # set it in next
__switch_to_no_mcck:
stm %r6,%r15,__SF_GPRS(%r15)# store __switch_to registers of prev task
st %r15,__THREAD_ksp(%r2) # store kernel stack to prev->tss.ksp
l %r15,__THREAD_ksp(%r3) # load kernel stack from next->tss.ksp
lm %r6,%r15,__SF_GPRS(%r15)# load __switch_to registers of next task
st %r3,__LC_CURRENT # __LC_CURRENT = current task struct
lctl %c4,%c4,__TASK_pid(%r3) # load pid to control reg. 4
l %r3,__THREAD_info(%r3) # load thread_info from task struct
st %r3,__LC_THREAD_INFO
ahi %r3,STACK_SIZE
st %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
CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
lh %r7,0x8a # get svc number from lowcore
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
sysc_vtime:
tm SP_PSW+1(%r15),0x01 # interrupting from user ?
bz BASED(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:
l %r9,__LC_THREAD_INFO # load pointer to thread_info struct
sla %r7,2 # *4 and test for svc 0
bnz BASED(sysc_nr_ok) # svc number > 0
# svc 0: system call number in %r1
cl %r1,BASED(.Lnr_syscalls)
bnl BASED(sysc_nr_ok)
lr %r7,%r1 # copy svc number to %r7
sla %r7,2 # *4
sysc_nr_ok:
mvc SP_ARGS(4,%r15),SP_R7(%r15)
sysc_do_restart:
tm __TI_flags+3(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
l %r8,sys_call_table-system_call(%r7,%r13) # get system call addr.
bnz BASED(sysc_tracesys)
basr %r14,%r8 # call sys_xxxx
st %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 ?
bno BASED(sysc_leave)
tm __TI_flags+3(%r9),_TIF_WORK_SVC
bnz BASED(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+3(%r9),_TIF_WORK_SVC
bz BASED(sysc_leave) # there is no work to do
#
# One of the work bits is on. Find out which one.
#
sysc_work:
tm __TI_flags+3(%r9),_TIF_MCCK_PENDING
bo BASED(sysc_mcck_pending)
tm __TI_flags+3(%r9),_TIF_NEED_RESCHED
bo BASED(sysc_reschedule)
tm __TI_flags+3(%r9),_TIF_SIGPENDING
bo BASED(sysc_sigpending)
tm __TI_flags+3(%r9),_TIF_RESTART_SVC
bo BASED(sysc_restart)
tm __TI_flags+3(%r9),_TIF_SINGLE_STEP
bo BASED(sysc_singlestep)
b BASED(sysc_leave)
#
# _TIF_NEED_RESCHED is set, call schedule
#
sysc_reschedule:
l %r1,BASED(.Lschedule)
la %r14,BASED(sysc_work_loop)
br %r1 # call scheduler
#
# _TIF_MCCK_PENDING is set, call handler
#
sysc_mcck_pending:
l %r1,BASED(.Ls390_handle_mcck)
la %r14,BASED(sysc_work_loop)
br %r1 # TIF bit will be cleared by handler
#
# _TIF_SIGPENDING is set, call do_signal
#
sysc_sigpending:
ni __TI_flags+3(%r9),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
la %r2,SP_PTREGS(%r15) # load pt_regs
sr %r3,%r3 # clear *oldset
l %r1,BASED(.Ldo_signal)
basr %r14,%r1 # call do_signal
tm __TI_flags+3(%r9),_TIF_RESTART_SVC
bo BASED(sysc_restart)
tm __TI_flags+3(%r9),_TIF_SINGLE_STEP
bo BASED(sysc_singlestep)
b BASED(sysc_leave) # out of here, do NOT recheck
#
# _TIF_RESTART_SVC is set, set up registers and restart svc
#
sysc_restart:
ni __TI_flags+3(%r9),255-_TIF_RESTART_SVC # clear TIF_RESTART_SVC
l %r7,SP_R2(%r15) # load new svc number
sla %r7,2
mvc SP_R2(4,%r15),SP_ORIG_R2(%r15) # restore first argument
lm %r2,%r6,SP_R2(%r15) # load svc arguments
b BASED(sysc_do_restart) # restart svc
#
# _TIF_SINGLE_STEP is set, call do_single_step
#
sysc_singlestep:
ni __TI_flags+3(%r9),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
mvi SP_TRAP+1(%r15),0x28 # set trap indication to pgm check
la %r2,SP_PTREGS(%r15) # address of register-save area
l %r1,BASED(.Lhandle_per) # load adr. of per handler
la %r14,BASED(sysc_return) # load adr. of system return
br %r1 # branch to do_single_step
__critical_end:
#
# call trace before and after sys_call
#
sysc_tracesys:
l %r1,BASED(.Ltrace)
la %r2,SP_PTREGS(%r15) # load pt_regs
la %r3,0
srl %r7,2
st %r7,SP_R2(%r15)
basr %r14,%r1
clc SP_R2(4,%r15),BASED(.Lnr_syscalls)
bnl BASED(sysc_tracenogo)
l %r7,SP_R2(%r15) # strace might have changed the
sll %r7,2 # system call
l %r8,sys_call_table-system_call(%r7,%r13)
sysc_tracego:
lm %r3,%r6,SP_R3(%r15)
l %r2,SP_ORIG_R2(%r15)
basr %r14,%r8 # call sys_xxx
st %r2,SP_R2(%r15) # store return value
sysc_tracenogo:
tm __TI_flags+3(%r9),(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT)
bz BASED(sysc_return)
l %r1,BASED(.Ltrace)
la %r2,SP_PTREGS(%r15) # load pt_regs
la %r3,1
la %r14,BASED(sysc_return)
br %r1
#
# a new process exits the kernel with ret_from_fork
#
.globl ret_from_fork
ret_from_fork:
l %r13,__LC_SVC_NEW_PSW+4
l %r9,__LC_THREAD_INFO # load pointer to thread_info struct
tm SP_PSW+1(%r15),0x01 # forking a kernel thread ?
bo BASED(0f)
st %r15,SP_R15(%r15) # store stack pointer for new kthread
0: l %r1,BASED(.Lschedtail)
basr %r14,%r1
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
b BASED(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
l %r1,BASED(.Lclone)
br %r1 # branch to sys_clone
sys_fork_glue:
la %r2,SP_PTREGS(%r15) # load pt_regs
l %r1,BASED(.Lfork)
br %r1 # branch to sys_fork
sys_vfork_glue:
la %r2,SP_PTREGS(%r15) # load pt_regs
l %r1,BASED(.Lvfork)
br %r1 # branch to sys_vfork
sys_execve_glue:
la %r2,SP_PTREGS(%r15) # load pt_regs
l %r1,BASED(.Lexecve)
lr %r12,%r14 # save return address
basr %r14,%r1 # call sys_execve
ltr %r2,%r2 # check if execve failed
bnz 0(%r12) # it did fail -> store result in gpr2
b 4(%r12) # SKIP ST 2,SP_R2(15) after BASR 14,8
# in system_call/sysc_tracesys
sys_sigreturn_glue:
la %r2,SP_PTREGS(%r15) # load pt_regs as parameter
l %r1,BASED(.Lsigreturn)
br %r1 # branch to sys_sigreturn
sys_rt_sigreturn_glue:
la %r2,SP_PTREGS(%r15) # load pt_regs as parameter
l %r1,BASED(.Lrt_sigreturn)
br %r1 # branch to sys_sigreturn
#
# 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:
lr %r5,%r4 # move mask back
lr %r4,%r3 # move history1 parameter
lr %r3,%r2 # move history0 parameter
la %r2,SP_PTREGS(%r15) # load pt_regs as first parameter
l %r1,BASED(.Lsigsuspend)
la %r14,4(%r14) # skip store of return value
br %r1 # branch to sys_sigsuspend
sys_rt_sigsuspend_glue:
lr %r4,%r3 # move sigsetsize parameter
lr %r3,%r2 # move unewset parameter
la %r2,SP_PTREGS(%r15) # load pt_regs as first parameter
l %r1,BASED(.Lrt_sigsuspend)
la %r14,4(%r14) # skip store of return value
br %r1 # branch to sys_rt_sigsuspend
sys_sigaltstack_glue:
la %r4,SP_PTREGS(%r15) # load pt_regs as parameter
l %r1,BASED(.Lsigaltstack)
br %r1 # branch to sys_sigreturn
/*
* 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
bnz BASED(pgm_per) # got per exception -> special case
SAVE_ALL __LC_PGM_OLD_PSW,__LC_SAVE_AREA,1
CREATE_STACK_FRAME __LC_PGM_OLD_PSW,__LC_SAVE_AREA
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
tm SP_PSW+1(%r15),0x01 # interrupting from user ?
bz BASED(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
l %r9,__LC_THREAD_INFO # load pointer to thread_info struct
l %r3,__LC_PGM_ILC # load program interruption code
la %r8,0x7f
nr %r8,%r3
pgm_do_call:
l %r7,BASED(.Ljump_table)
sll %r8,2
l %r7,0(%r8,%r7) # load address of handler routine
la %r2,SP_PTREGS(%r15) # address of register-save area
la %r14,BASED(sysc_return)
br %r7 # branch to interrupt-handler
#
# handle per exception
#
pgm_per:
tm __LC_PGM_OLD_PSW,0x40 # test if per event recording is on
bnz BASED(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(8),__LC_SVC_NEW_PSW
be BASED(pgm_svcper)
# no interesting special case, ignore PER event
lm %r12,%r15,__LC_SAVE_AREA
lpsw 0x28
#
# Normal per exception
#
pgm_per_std:
SAVE_ALL __LC_PGM_OLD_PSW,__LC_SAVE_AREA,1
CREATE_STACK_FRAME __LC_PGM_OLD_PSW,__LC_SAVE_AREA
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
tm SP_PSW+1(%r15),0x01 # interrupting from user ?
bz BASED(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
l %r9,__LC_THREAD_INFO # load pointer to thread_info struct
l %r1,__TI_task(%r9)
mvc __THREAD_per+__PER_atmid(2,%r1),__LC_PER_ATMID
mvc __THREAD_per+__PER_address(4,%r1),__LC_PER_ADDRESS
mvc __THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID
oi __TI_flags+3(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
l %r3,__LC_PGM_ILC # load program interruption code
la %r8,0x7f
nr %r8,%r3 # clear per-event-bit and ilc
be BASED(sysc_return) # only per or per+check ?
b BASED(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
CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
tm SP_PSW+1(%r15),0x01 # interrupting from user ?
bz BASED(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
lh %r7,0x8a # get svc number from lowcore
l %r9,__LC_THREAD_INFO # load pointer to thread_info struct
l %r1,__TI_task(%r9)
mvc __THREAD_per+__PER_atmid(2,%r1),__LC_PER_ATMID
mvc __THREAD_per+__PER_address(4,%r1),__LC_PER_ADDRESS
mvc __THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID
oi __TI_flags+3(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
b BASED(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+16
SAVE_ALL __LC_IO_OLD_PSW,__LC_SAVE_AREA+16,0
CREATE_STACK_FRAME __LC_IO_OLD_PSW,__LC_SAVE_AREA+16
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
tm SP_PSW+1(%r15),0x01 # interrupting from user ?
bz BASED(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
l %r9,__LC_THREAD_INFO # load pointer to thread_info struct
l %r1,BASED(.Ldo_IRQ) # load address of do_IRQ
la %r2,SP_PTREGS(%r15) # address of register-save area
basr %r14,%r1 # branch to standard irq handler
io_return:
tm SP_PSW+1(%r15),0x01 # returning to user ?
#ifdef CONFIG_PREEMPT
bno BASED(io_preempt) # no -> check for preemptive scheduling
#else
bno BASED(io_leave) # no-> skip resched & signal
#endif
tm __TI_flags+3(%r9),_TIF_WORK_INT
bnz BASED(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)
bnz BASED(io_leave)
l %r1,SP_R15(%r15)
s %r1,BASED(.Lc_spsize)
mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain
lr %r15,%r1
io_resume_loop:
tm __TI_flags+3(%r9),_TIF_NEED_RESCHED
bno BASED(io_leave)
mvc __TI_precount(4,%r9),BASED(.Lc_pactive)
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
l %r1,BASED(.Lschedule)
basr %r14,%r1 # call schedule
stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
xc __TI_precount(4,%r9),__TI_precount(%r9)
b BASED(io_resume_loop)
#endif
#
# switch to kernel stack, then check the TIF bits
#
io_work:
l %r1,__LC_KERNEL_STACK
s %r1,BASED(.Lc_spsize)
mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain
lr %r15,%r1
#
# One of the work bits is on. Find out which one.
# Checked are: _TIF_SIGPENDING, _TIF_NEED_RESCHED and _TIF_MCCK_PENDING
#
io_work_loop:
tm __TI_flags+3(%r9),_TIF_MCCK_PENDING
bo BASED(io_mcck_pending)
tm __TI_flags+3(%r9),_TIF_NEED_RESCHED
bo BASED(io_reschedule)
tm __TI_flags+3(%r9),_TIF_SIGPENDING
bo BASED(io_sigpending)
b BASED(io_leave)
#
# _TIF_MCCK_PENDING is set, call handler
#
io_mcck_pending:
l %r1,BASED(.Ls390_handle_mcck)
l %r14,BASED(io_work_loop)
br %r1 # TIF bit will be cleared by handler
#
# _TIF_NEED_RESCHED is set, call schedule
#
io_reschedule:
l %r1,BASED(.Lschedule)
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
basr %r14,%r1 # call scheduler
stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
tm __TI_flags+3(%r9),_TIF_WORK_INT
bz BASED(io_leave) # there is no work to do
b BASED(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
sr %r3,%r3 # clear *oldset
l %r1,BASED(.Ldo_signal)
basr %r14,%r1 # call do_signal
stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
b BASED(io_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+16
SAVE_ALL __LC_EXT_OLD_PSW,__LC_SAVE_AREA+16,0
CREATE_STACK_FRAME __LC_EXT_OLD_PSW,__LC_SAVE_AREA+16
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
tm SP_PSW+1(%r15),0x01 # interrupting from user ?
bz BASED(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
l %r9,__LC_THREAD_INFO # load pointer to thread_info struct
la %r2,SP_PTREGS(%r15) # address of register-save area
lh %r3,__LC_EXT_INT_CODE # get interruption code
l %r1,BASED(.Ldo_extint)
basr %r14,%r1
b BASED(io_return)
/*
* Machine check handler routines
*/
.globl mcck_int_handler
mcck_int_handler:
spt __LC_CPU_TIMER_SAVE_AREA # revalidate cpu timer
lm %r0,%r15,__LC_GPREGS_SAVE_AREA # revalidate gprs
SAVE_ALL_BASE __LC_SAVE_AREA+32
la %r12,__LC_MCK_OLD_PSW
tm __LC_MCCK_CODE,0x80 # system damage?
bo BASED(mcck_int_main) # yes -> rest of mcck code invalid
tm __LC_MCCK_CODE+5,0x02 # stored cpu timer value valid?
bo BASED(0f)
spt __LC_LAST_UPDATE_TIMER # revalidate cpu timer
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
mvc __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
mvc __LC_LAST_UPDATE_TIMER(8),__LC_EXIT_TIMER
0: tm __LC_MCCK_CODE+2,0x08 # mwp of old psw valid?
bno BASED(mcck_no_vtime) # no -> skip cleanup critical
tm __LC_MCK_OLD_PSW+1,0x01 # interrupting from user ?
bz BASED(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
0:
tm __LC_MCCK_CODE+2,0x09 # mwp + ia of old psw valid?
bno BASED(mcck_int_main) # no -> skip cleanup critical
tm __LC_MCK_OLD_PSW+1,0x01 # test problem state bit
bnz BASED(mcck_int_main) # from user -> load async stack
clc __LC_MCK_OLD_PSW+4(4),BASED(.Lcritical_end)
bhe BASED(mcck_int_main)
clc __LC_MCK_OLD_PSW+4(4),BASED(.Lcritical_start)
bl BASED(mcck_int_main)
l %r14,BASED(.Lcleanup_critical)
basr %r14,%r14
mcck_int_main:
l %r14,__LC_PANIC_STACK # are we already on the panic stack?
slr %r14,%r15
sra %r14,PAGE_SHIFT
be BASED(0f)
l %r15,__LC_PANIC_STACK # load panic stack
0: CREATE_STACK_FRAME __LC_MCK_OLD_PSW,__LC_SAVE_AREA+32
l %r9,__LC_THREAD_INFO # load pointer to thread_info struct
la %r2,SP_PTREGS(%r15) # load pt_regs
l %r1,BASED(.Ls390_mcck)
basr %r14,%r1 # call machine check handler
tm SP_PSW+1(%r15),0x01 # returning to user ?
bno BASED(mcck_return)
l %r1,__LC_KERNEL_STACK # switch to kernel stack
s %r1,BASED(.Lc_spsize)
mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain
lr %r15,%r1
stosm __SF_EMPTY(%r15),0x04 # turn dat on
tm __TI_flags+3(%r9),_TIF_MCCK_PENDING
bno BASED(mcck_return)
l %r1,BASED(.Ls390_handle_mcck)
basr %r14,%r1 # call machine check handler
mcck_return:
RESTORE_ALL 0
#ifdef CONFIG_SMP
/*
* Restart interruption handler, kick starter for additional CPUs
*/
.globl restart_int_handler
restart_int_handler:
l %r15,__LC_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
stosm __SF_EMPTY(%r15),0x04 # now we can turn dat on
basr %r14,0
l %r14,restart_addr-.(%r14)
br %r14 # branch to start_secondary
restart_addr:
.long 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:
lpsw restart_crash-restart_base(%r1)
.align 8
restart_crash:
.long 0x000a0000,0x00000000
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:
l %r15,__LC_PANIC_STACK # change to panic stack
sl %r15,BASED(.Lc_spsize)
mvc SP_PSW(8,%r15),0(%r12) # move user PSW to stack
stm %r0,%r11,SP_R0(%r15) # store gprs %r0-%r11 to kernel stack
la %r1,__LC_SAVE_AREA
ch %r12,BASED(.L0x020) # old psw addr == __LC_SVC_OLD_PSW ?
be BASED(0f)
ch %r12,BASED(.L0x028) # old psw addr == __LC_PGM_OLD_PSW ?
be BASED(0f)
la %r1,__LC_SAVE_AREA+16
0: mvc SP_R12(16,%r15),0(%r1) # move %r12-%r15 to stack
xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) # clear back chain
l %r1,BASED(1f) # branch to kernel_stack_overflow
la %r2,SP_PTREGS(%r15) # load pt_regs
br %r1
1: .long kernel_stack_overflow
#endif
cleanup_table_system_call:
.long system_call + 0x80000000, sysc_do_svc + 0x80000000
cleanup_table_sysc_return:
.long sysc_return + 0x80000000, sysc_leave + 0x80000000
cleanup_table_sysc_leave:
.long sysc_leave + 0x80000000, sysc_work_loop + 0x80000000
cleanup_table_sysc_work_loop:
.long sysc_work_loop + 0x80000000, sysc_reschedule + 0x80000000
cleanup_critical:
clc 4(4,%r12),BASED(cleanup_table_system_call)
bl BASED(0f)
clc 4(4,%r12),BASED(cleanup_table_system_call+4)
bl BASED(cleanup_system_call)
0:
clc 4(4,%r12),BASED(cleanup_table_sysc_return)
bl BASED(0f)
clc 4(4,%r12),BASED(cleanup_table_sysc_return+4)
bl BASED(cleanup_sysc_return)
0:
clc 4(4,%r12),BASED(cleanup_table_sysc_leave)
bl BASED(0f)
clc 4(4,%r12),BASED(cleanup_table_sysc_leave+4)
bl BASED(cleanup_sysc_leave)
0:
clc 4(4,%r12),BASED(cleanup_table_sysc_work_loop)
bl BASED(0f)
clc 4(4,%r12),BASED(cleanup_table_sysc_work_loop+4)
bl BASED(cleanup_sysc_return)
0:
br %r14
cleanup_system_call:
mvc __LC_RETURN_PSW(8),0(%r12)
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+4)
bh BASED(0f)
mvc __LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER
0: clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+8)
bhe BASED(cleanup_vtime)
#endif
clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn)
bh BASED(0f)
mvc __LC_SAVE_AREA(16),__LC_SAVE_AREA+16
0: st %r13,__LC_SAVE_AREA+20
SAVE_ALL __LC_SVC_OLD_PSW,__LC_SAVE_AREA,1
CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
st %r15,__LC_SAVE_AREA+28
lh %r7,0x8a
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
cleanup_vtime:
clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+12)
bhe BASED(cleanup_stime)
tm SP_PSW+1(%r15),0x01 # interrupting from user ?
bz BASED(cleanup_novtime)
UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
cleanup_stime:
clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+16)
bh BASED(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+4(4),BASED(cleanup_table_system_call+4)
la %r12,__LC_RETURN_PSW
br %r14
cleanup_system_call_insn:
.long sysc_saveall + 0x80000000
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
.long system_call + 0x80000000
.long sysc_vtime + 0x80000000
.long sysc_stime + 0x80000000
.long sysc_update + 0x80000000
#endif
cleanup_sysc_return:
mvc __LC_RETURN_PSW(4),0(%r12)
mvc __LC_RETURN_PSW+4(4),BASED(cleanup_table_sysc_return)
la %r12,__LC_RETURN_PSW
br %r14
cleanup_sysc_leave:
clc 4(4,%r12),BASED(cleanup_sysc_leave_insn)
be BASED(0f)
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
mvc __LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER
clc 4(4,%r12),BASED(cleanup_sysc_leave_insn+4)
be BASED(0f)
#endif
mvc __LC_RETURN_PSW(8),SP_PSW(%r15)
mvc __LC_SAVE_AREA+16(16),SP_R12(%r15)
lm %r0,%r11,SP_R0(%r15)
l %r15,SP_R15(%r15)
0: la %r12,__LC_RETURN_PSW
br %r14
cleanup_sysc_leave_insn:
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
.long sysc_leave + 14 + 0x80000000
#endif
.long sysc_leave + 10 + 0x80000000
/*
* Integer constants
*/
.align 4
.Lc_spsize: .long SP_SIZE
.Lc_overhead: .long STACK_FRAME_OVERHEAD
.Lc_pactive: .long PREEMPT_ACTIVE
.Lnr_syscalls: .long NR_syscalls
.L0x018: .short 0x018
.L0x020: .short 0x020
.L0x028: .short 0x028
.L0x030: .short 0x030
.L0x038: .short 0x038
.Lc_1: .long 1
/*
* Symbol constants
*/
.Ls390_mcck: .long s390_do_machine_check
.Ls390_handle_mcck:
.long s390_handle_mcck
.Ldo_IRQ: .long do_IRQ
.Ldo_extint: .long do_extint
.Ldo_signal: .long do_signal
.Lhandle_per: .long do_single_step
.Ljump_table: .long pgm_check_table
.Lschedule: .long schedule
.Lclone: .long sys_clone
.Lexecve: .long sys_execve
.Lfork: .long sys_fork
.Lrt_sigreturn:.long sys_rt_sigreturn
.Lrt_sigsuspend:
.long sys_rt_sigsuspend
.Lsigreturn: .long sys_sigreturn
.Lsigsuspend: .long sys_sigsuspend
.Lsigaltstack: .long sys_sigaltstack
.Ltrace: .long syscall_trace
.Lvfork: .long sys_vfork
.Lschedtail: .long schedule_tail
.Lcritical_start:
.long __critical_start + 0x80000000
.Lcritical_end:
.long __critical_end + 0x80000000
.Lcleanup_critical:
.long cleanup_critical
#define SYSCALL(esa,esame,emu) .long esa
.globl sys_call_table
sys_call_table:
#include "syscalls.S"
#undef SYSCALL