linux_dsm_epyc7002/arch/s390/kernel/entry.S
Martin Schwidefsky 9ec2708053 [S390] fix kprobes single stepping
Fix kprobes after git commit 1e54622e04
broke it. The kprobe_handler is now called with interrupts in the state
at the time of the breakpoint. The single step of the replaced instruction
is done with interrupts off which makes it necessary to enable and disable
the interupts in the kprobes code.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-10-29 16:50:50 +02:00

1085 lines
32 KiB
ArmAsm

/*
* arch/s390/kernel/entry.S
* S390 low-level entry points.
*
* Copyright (C) IBM Corp. 1999,2006
* 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/init.h>
#include <asm/cache.h>
#include <asm/errno.h>
#include <asm/ptrace.h>
#include <asm/thread_info.h>
#include <asm/asm-offsets.h>
#include <asm/unistd.h>
#include <asm/page.h>
/*
* 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_SVCNR = STACK_FRAME_OVERHEAD + __PT_SVCNR
SP_SIZE = STACK_FRAME_OVERHEAD + __PT_SIZE
_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
_TIF_MCCK_PENDING | _TIF_RESTART_SVC | _TIF_SINGLE_STEP )
_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
_TIF_MCCK_PENDING)
_TIF_SYSCALL = (_TIF_SYSCALL_TRACE>>8 | _TIF_SYSCALL_AUDIT>>8 | \
_TIF_SECCOMP>>8 | _TIF_SYSCALL_TRACEPOINT>>8)
STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
STACK_SIZE = 1 << STACK_SHIFT
#define BASED(name) name-system_call(%r13)
#ifdef CONFIG_TRACE_IRQFLAGS
.macro TRACE_IRQS_ON
basr %r2,%r0
l %r1,BASED(.Ltrace_irq_on_caller)
basr %r14,%r1
.endm
.macro TRACE_IRQS_OFF
basr %r2,%r0
l %r1,BASED(.Ltrace_irq_off_caller)
basr %r14,%r1
.endm
#else
#define TRACE_IRQS_ON
#define TRACE_IRQS_OFF
#endif
#ifdef CONFIG_LOCKDEP
.macro LOCKDEP_SYS_EXIT
tm SP_PSW+1(%r15),0x01 # returning to user ?
jz 0f
l %r1,BASED(.Llockdep_sys_exit)
basr %r14,%r1
0:
.endm
#else
#define LOCKDEP_SYS_EXIT
#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 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
.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_SVC psworg,savearea
la %r12,\psworg
l %r15,__LC_KERNEL_STACK # problem state -> load ksp
.endm
.macro SAVE_ALL_SYNC psworg,savearea
la %r12,\psworg
tm \psworg+1,0x01 # test problem state bit
bz BASED(2f) # skip stack setup save
l %r15,__LC_KERNEL_STACK # problem state -> load ksp
#ifdef CONFIG_CHECK_STACK
b BASED(3f)
2: tml %r15,STACK_SIZE - CONFIG_STACK_GUARD
bz BASED(stack_overflow)
3:
#endif
2:
.endm
.macro SAVE_ALL_ASYNC psworg,savearea
la %r12,\psworg
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 1(%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
#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
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 psworg,sync
mvc \psworg(8),SP_PSW(%r15) # move user PSW to lowcore
.if !\sync
ni \psworg+1,0xfd # clear wait state bit
.endif
lm %r0,%r15,SP_R0(%r15) # load gprs 0-15 of user
stpt __LC_EXIT_TIMER
lpsw \psworg # back to caller
.endm
.macro REENABLE_IRQS
mvc __SF_EMPTY(1,%r15),SP_PSW(%r15)
ni __SF_EMPTY(%r15),0xbf
ssm __SF_EMPTY(%r15)
.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:
stpt __LC_SYNC_ENTER_TIMER
sysc_saveall:
SAVE_ALL_BASE __LC_SAVE_AREA
SAVE_ALL_SVC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
lh %r7,0x8a # get svc number from lowcore
sysc_vtime:
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
sysc_do_svc:
l %r9,__LC_THREAD_INFO # load pointer to thread_info struct
ltr %r7,%r7 # 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
sysc_nr_ok:
sth %r7,SP_SVCNR(%r15)
sll %r7,2 # svc number *4
l %r8,BASED(.Lsysc_table)
tm __TI_flags+2(%r9),_TIF_SYSCALL
mvc SP_ARGS(4,%r15),SP_R7(%r15)
l %r8,0(%r7,%r8) # 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)
sysc_return:
LOCKDEP_SYS_EXIT
sysc_tif:
tm __TI_flags+3(%r9),_TIF_WORK_SVC
bnz BASED(sysc_work) # there is work to do (signals etc.)
sysc_restore:
RESTORE_ALL __LC_RETURN_PSW,1
sysc_done:
#
# There is work to do, but first we need to check if we return to userspace.
#
sysc_work:
tm SP_PSW+1(%r15),0x01 # returning to user ?
bno BASED(sysc_restore)
#
# One of the work bits is on. Find out which one.
#
sysc_work_tif:
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_NOTIFY_RESUME
bo BASED(sysc_notify_resume)
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_return) # beware of critical section cleanup
#
# _TIF_NEED_RESCHED is set, call schedule
#
sysc_reschedule:
l %r1,BASED(.Lschedule)
la %r14,BASED(sysc_return)
br %r1 # call scheduler
#
# _TIF_MCCK_PENDING is set, call handler
#
sysc_mcck_pending:
l %r1,BASED(.Ls390_handle_mcck)
la %r14,BASED(sysc_return)
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
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_return)
#
# _TIF_NOTIFY_RESUME is set, call do_notify_resume
#
sysc_notify_resume:
la %r2,SP_PTREGS(%r15) # load pt_regs
l %r1,BASED(.Ldo_notify_resume)
la %r14,BASED(sysc_return)
br %r1 # call do_notify_resume
#
# _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
mvc SP_R2(4,%r15),SP_ORIG_R2(%r15) # restore first argument
lm %r2,%r6,SP_R2(%r15) # load svc arguments
b BASED(sysc_nr_ok) # 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_SVCNR(%r15),0xff # set trap indication to pgm check
mvi SP_SVCNR+1(%r15),0xff
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
#
# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
# and after the system call
#
sysc_tracesys:
l %r1,BASED(.Ltrace_entry)
la %r2,SP_PTREGS(%r15) # load pt_regs
la %r3,0
srl %r7,2
st %r7,SP_R2(%r15)
basr %r14,%r1
cl %r2,BASED(.Lnr_syscalls)
bnl BASED(sysc_tracenogo)
l %r8,BASED(.Lsysc_table)
lr %r7,%r2
sll %r7,2 # svc number *4
l %r8,0(%r7,%r8)
sysc_tracego:
lm %r3,%r6,SP_R3(%r15)
mvc SP_ARGS(4,%r15),SP_R7(%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+2(%r9),_TIF_SYSCALL
bz BASED(sysc_return)
l %r1,BASED(.Ltrace_exit)
la %r2,SP_PTREGS(%r15) # load pt_regs
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
TRACE_IRQS_ON
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
b BASED(sysc_tracenogo)
#
# kernel_execve function needs to deal with pt_regs that is not
# at the usual place
#
.globl kernel_execve
kernel_execve:
stm %r12,%r15,48(%r15)
lr %r14,%r15
l %r13,__LC_SVC_NEW_PSW+4
s %r15,BASED(.Lc_spsize)
st %r14,__SF_BACKCHAIN(%r15)
la %r12,SP_PTREGS(%r15)
xc 0(__PT_SIZE,%r12),0(%r12)
l %r1,BASED(.Ldo_execve)
lr %r5,%r12
basr %r14,%r1
ltr %r2,%r2
be BASED(0f)
a %r15,BASED(.Lc_spsize)
lm %r12,%r15,48(%r15)
br %r14
# execve succeeded.
0: stnsm __SF_EMPTY(%r15),0xfc # disable interrupts
l %r15,__LC_KERNEL_STACK # load ksp
s %r15,BASED(.Lc_spsize) # make room for registers & psw
l %r9,__LC_THREAD_INFO
mvc SP_PTREGS(__PT_SIZE,%r15),0(%r12) # copy pt_regs
xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
l %r1,BASED(.Lexecve_tail)
basr %r14,%r1
b BASED(sysc_return)
/*
* 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?).
*/
stpt __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_SYNC __LC_PGM_OLD_PSW,__LC_SAVE_AREA
CREATE_STACK_FRAME __LC_PGM_OLD_PSW,__LC_SAVE_AREA
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:
l %r9,__LC_THREAD_INFO # load pointer to thread_info struct
l %r3,__LC_PGM_ILC # load program interruption code
l %r4,__LC_TRANS_EXC_CODE
REENABLE_IRQS
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
basr %r14,%r7 # branch to interrupt-handler
pgm_exit:
b BASED(sysc_return)
#
# 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_SYNC __LC_PGM_OLD_PSW,__LC_SAVE_AREA
CREATE_STACK_FRAME __LC_PGM_OLD_PSW,__LC_SAVE_AREA
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:
l %r9,__LC_THREAD_INFO # load pointer to thread_info struct
l %r1,__TI_task(%r9)
tm SP_PSW+1(%r15),0x01 # kernel per event ?
bz BASED(kernel_per)
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
l %r4,__LC_TRANS_EXC_CODE
REENABLE_IRQS
la %r8,0x7f
nr %r8,%r3 # clear per-event-bit and ilc
be BASED(pgm_exit2) # only per or per+check ?
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
basr %r14,%r7 # branch to interrupt-handler
pgm_exit2:
b BASED(sysc_return)
#
# it was a single stepped SVC that is causing all the trouble
#
pgm_svcper:
SAVE_ALL_SYNC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
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
lh %r7,0x8a # get svc number from lowcore
l %r9,__LC_THREAD_INFO # load pointer to thread_info struct
l %r8,__TI_task(%r9)
mvc __THREAD_per+__PER_atmid(2,%r8),__LC_PER_ATMID
mvc __THREAD_per+__PER_address(4,%r8),__LC_PER_ADDRESS
mvc __THREAD_per+__PER_access_id(1,%r8),__LC_PER_ACCESS_ID
oi __TI_flags+3(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
lm %r2,%r6,SP_R2(%r15) # load svc arguments
b BASED(sysc_do_svc)
#
# per was called from kernel, must be kprobes
#
kernel_per:
REENABLE_IRQS
mvi SP_SVCNR(%r15),0xff # set trap indication to pgm check
mvi SP_SVCNR+1(%r15),0xff
la %r2,SP_PTREGS(%r15) # address of register-save area
l %r1,BASED(.Lhandle_per) # load adr. of per handler
basr %r14,%r1 # branch to do_single_step
b BASED(pgm_exit)
/*
* IO interrupt handler routine
*/
.globl io_int_handler
io_int_handler:
stck __LC_INT_CLOCK
stpt __LC_ASYNC_ENTER_TIMER
SAVE_ALL_BASE __LC_SAVE_AREA+16
SAVE_ALL_ASYNC __LC_IO_OLD_PSW,__LC_SAVE_AREA+16
CREATE_STACK_FRAME __LC_IO_OLD_PSW,__LC_SAVE_AREA+16
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:
TRACE_IRQS_OFF
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:
LOCKDEP_SYS_EXIT
TRACE_IRQS_ON
io_tif:
tm __TI_flags+3(%r9),_TIF_WORK_INT
bnz BASED(io_work) # there is work to do (signals etc.)
io_restore:
RESTORE_ALL __LC_RETURN_PSW,0
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 SP_PSW+1(%r15),0x01 # returning to user ?
bo BASED(io_work_user) # yes -> do resched & signal
#ifdef CONFIG_PREEMPT
# check for preemptive scheduling
icm %r0,15,__TI_precount(%r9)
bnz BASED(io_restore) # preemption disabled
tm __TI_flags+3(%r9),_TIF_NEED_RESCHED
bno BASED(io_restore)
# switch to kernel stack
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
# TRACE_IRQS_ON already done at io_return, call
# TRACE_IRQS_OFF to keep things symmetrical
TRACE_IRQS_OFF
l %r1,BASED(.Lpreempt_schedule_irq)
basr %r14,%r1 # call preempt_schedule_irq
b BASED(io_return)
#else
b BASED(io_restore)
#endif
#
# Need to do work before returning to userspace, switch to kernel stack
#
io_work_user:
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_NOTIFY_RESUME, _TIF_NEED_RESCHED
# and _TIF_MCCK_PENDING
#
io_work_tif:
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)
tm __TI_flags+3(%r9),_TIF_NOTIFY_RESUME
bo BASED(io_notify_resume)
b BASED(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(.Ls390_handle_mcck)
basr %r14,%r1 # TIF bit will be cleared by handler
TRACE_IRQS_OFF
b BASED(io_return)
#
# _TIF_NEED_RESCHED is set, call schedule
#
io_reschedule:
# TRACE_IRQS_ON already done at io_return
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
TRACE_IRQS_OFF
b BASED(io_return)
#
# _TIF_SIGPENDING is set, call do_signal
#
io_sigpending:
# TRACE_IRQS_ON already done at io_return
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
la %r2,SP_PTREGS(%r15) # load pt_regs
l %r1,BASED(.Ldo_signal)
basr %r14,%r1 # call do_signal
stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
TRACE_IRQS_OFF
b BASED(io_return)
#
# _TIF_SIGPENDING is set, call do_signal
#
io_notify_resume:
# TRACE_IRQS_ON already done at io_return
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
la %r2,SP_PTREGS(%r15) # load pt_regs
l %r1,BASED(.Ldo_notify_resume)
basr %r14,%r1 # call do_signal
stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
TRACE_IRQS_OFF
b BASED(io_return)
/*
* External interrupt handler routine
*/
.globl ext_int_handler
ext_int_handler:
stck __LC_INT_CLOCK
stpt __LC_ASYNC_ENTER_TIMER
SAVE_ALL_BASE __LC_SAVE_AREA+16
SAVE_ALL_ASYNC __LC_EXT_OLD_PSW,__LC_SAVE_AREA+16
CREATE_STACK_FRAME __LC_EXT_OLD_PSW,__LC_SAVE_AREA+16
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:
l %r9,__LC_THREAD_INFO # load pointer to thread_info struct
TRACE_IRQS_OFF
la %r2,SP_PTREGS(%r15) # address of register-save area
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
b BASED(io_return)
__critical_end:
/*
* Machine check handler routines
*/
.globl mcck_int_handler
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
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
mvc __LC_MCCK_ENTER_TIMER(8),__LC_CPU_TIMER_SAVE_AREA
tm __LC_MCCK_CODE+5,0x02 # stored cpu timer value valid?
bo BASED(1f)
la %r14,__LC_SYNC_ENTER_TIMER
clc 0(8,%r14),__LC_ASYNC_ENTER_TIMER
bl BASED(0f)
la %r14,__LC_ASYNC_ENTER_TIMER
0: clc 0(8,%r14),__LC_EXIT_TIMER
bl BASED(0f)
la %r14,__LC_EXIT_TIMER
0: clc 0(8,%r14),__LC_LAST_UPDATE_TIMER
bl BASED(0f)
la %r14,__LC_LAST_UPDATE_TIMER
0: spt 0(%r14)
mvc __LC_MCCK_ENTER_TIMER(8),0(%r14)
1: 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
tm __LC_MCCK_CODE+2,0x08 # mwp of old psw valid?
bno BASED(mcck_no_vtime) # no -> skip cleanup critical
tm SP_PSW+1(%r15),0x01 # interrupting from user ?
bz BASED(mcck_no_vtime)
UPDATE_VTIME __LC_EXIT_TIMER,__LC_MCCK_ENTER_TIMER,__LC_USER_TIMER
UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
mvc __LC_LAST_UPDATE_TIMER(8),__LC_MCCK_ENTER_TIMER
mcck_no_vtime:
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)
TRACE_IRQS_OFF
l %r1,BASED(.Ls390_handle_mcck)
basr %r14,%r1 # call machine check handler
TRACE_IRQS_ON
mcck_return:
mvc __LC_RETURN_MCCK_PSW(8),SP_PSW(%r15) # move return PSW
ni __LC_RETURN_MCCK_PSW+1,0xfd # clear wait state bit
tm __LC_RETURN_MCCK_PSW+1,0x01 # returning to user ?
bno BASED(0f)
lm %r0,%r15,SP_R0(%r15) # load gprs 0-15
stpt __LC_EXIT_TIMER
lpsw __LC_RETURN_MCCK_PSW # back to caller
0: lm %r0,%r15,SP_R0(%r15) # load gprs 0-15
lpsw __LC_RETURN_MCCK_PSW # back to caller
RESTORE_ALL __LC_RETURN_MCCK_PSW,0
/*
* Restart interruption handler, kick starter for additional CPUs
*/
#ifdef CONFIG_SMP
__CPUINIT
.globl restart_int_handler
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_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
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
.align 8
restart_vtime:
.long 0x7fffffff,0xffffffff
.previous
#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_tif:
.long sysc_tif + 0x80000000, sysc_restore + 0x80000000
cleanup_table_sysc_restore:
.long sysc_restore + 0x80000000, sysc_done + 0x80000000
cleanup_table_io_tif:
.long io_tif + 0x80000000, io_restore + 0x80000000
cleanup_table_io_restore:
.long io_restore + 0x80000000, io_done + 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_tif)
bl BASED(0f)
clc 4(4,%r12),BASED(cleanup_table_sysc_tif+4)
bl BASED(cleanup_sysc_tif)
0:
clc 4(4,%r12),BASED(cleanup_table_sysc_restore)
bl BASED(0f)
clc 4(4,%r12),BASED(cleanup_table_sysc_restore+4)
bl BASED(cleanup_sysc_restore)
0:
clc 4(4,%r12),BASED(cleanup_table_io_tif)
bl BASED(0f)
clc 4(4,%r12),BASED(cleanup_table_io_tif+4)
bl BASED(cleanup_io_tif)
0:
clc 4(4,%r12),BASED(cleanup_table_io_restore)
bl BASED(0f)
clc 4(4,%r12),BASED(cleanup_table_io_restore+4)
bl BASED(cleanup_io_restore)
0:
br %r14
cleanup_system_call:
mvc __LC_RETURN_PSW(8),0(%r12)
clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+4)
bh BASED(0f)
mvc __LC_SYNC_ENTER_TIMER(8),__LC_MCCK_ENTER_TIMER
c %r12,BASED(.Lmck_old_psw)
be BASED(0f)
mvc __LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER
0: c %r12,BASED(.Lmck_old_psw)
la %r12,__LC_SAVE_AREA+32
be BASED(0f)
la %r12,__LC_SAVE_AREA+16
0: clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+8)
bhe BASED(cleanup_vtime)
clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn)
bh BASED(0f)
mvc __LC_SAVE_AREA(16),0(%r12)
0: st %r13,4(%r12)
st %r12,__LC_SAVE_AREA+48 # argh
SAVE_ALL_SYNC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
l %r12,__LC_SAVE_AREA+48 # argh
st %r15,12(%r12)
lh %r7,0x8a
cleanup_vtime:
clc __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+12)
bhe BASED(cleanup_stime)
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
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
.long system_call + 0x80000000
.long sysc_vtime + 0x80000000
.long sysc_stime + 0x80000000
.long sysc_update + 0x80000000
cleanup_sysc_tif:
mvc __LC_RETURN_PSW(4),0(%r12)
mvc __LC_RETURN_PSW+4(4),BASED(cleanup_table_sysc_tif)
la %r12,__LC_RETURN_PSW
br %r14
cleanup_sysc_restore:
clc 4(4,%r12),BASED(cleanup_sysc_restore_insn)
be BASED(2f)
mvc __LC_EXIT_TIMER(8),__LC_MCCK_ENTER_TIMER
c %r12,BASED(.Lmck_old_psw)
be BASED(0f)
mvc __LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER
0: clc 4(4,%r12),BASED(cleanup_sysc_restore_insn+4)
be BASED(2f)
mvc __LC_RETURN_PSW(8),SP_PSW(%r15)
c %r12,BASED(.Lmck_old_psw)
la %r12,__LC_SAVE_AREA+32
be BASED(1f)
la %r12,__LC_SAVE_AREA+16
1: mvc 0(16,%r12),SP_R12(%r15)
lm %r0,%r11,SP_R0(%r15)
l %r15,SP_R15(%r15)
2: la %r12,__LC_RETURN_PSW
br %r14
cleanup_sysc_restore_insn:
.long sysc_done - 4 + 0x80000000
.long sysc_done - 8 + 0x80000000
cleanup_io_tif:
mvc __LC_RETURN_PSW(4),0(%r12)
mvc __LC_RETURN_PSW+4(4),BASED(cleanup_table_io_tif)
la %r12,__LC_RETURN_PSW
br %r14
cleanup_io_restore:
clc 4(4,%r12),BASED(cleanup_io_restore_insn)
be BASED(1f)
mvc __LC_EXIT_TIMER(8),__LC_MCCK_ENTER_TIMER
clc 4(4,%r12),BASED(cleanup_io_restore_insn+4)
be BASED(1f)
mvc __LC_RETURN_PSW(8),SP_PSW(%r15)
mvc __LC_SAVE_AREA+32(16),SP_R12(%r15)
lm %r0,%r11,SP_R0(%r15)
l %r15,SP_R15(%r15)
1: la %r12,__LC_RETURN_PSW
br %r14
cleanup_io_restore_insn:
.long io_done - 4 + 0x80000000
.long io_done - 8 + 0x80000000
/*
* Integer constants
*/
.align 4
.Lc_spsize: .long SP_SIZE
.Lc_overhead: .long STACK_FRAME_OVERHEAD
.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
.Lmck_old_psw: .long __LC_MCK_OLD_PSW
.Ldo_IRQ: .long do_IRQ
.Ldo_extint: .long do_extint
.Ldo_signal: .long do_signal
.Ldo_notify_resume:
.long do_notify_resume
.Lhandle_per: .long do_single_step
.Ldo_execve: .long do_execve
.Lexecve_tail: .long execve_tail
.Ljump_table: .long pgm_check_table
.Lschedule: .long schedule
#ifdef CONFIG_PREEMPT
.Lpreempt_schedule_irq:
.long preempt_schedule_irq
#endif
.Ltrace_entry: .long do_syscall_trace_enter
.Ltrace_exit: .long do_syscall_trace_exit
.Lschedtail: .long schedule_tail
.Lsysc_table: .long sys_call_table
#ifdef CONFIG_TRACE_IRQFLAGS
.Ltrace_irq_on_caller:
.long trace_hardirqs_on_caller
.Ltrace_irq_off_caller:
.long trace_hardirqs_off_caller
#endif
#ifdef CONFIG_LOCKDEP
.Llockdep_sys_exit:
.long lockdep_sys_exit
#endif
.Lcritical_start:
.long __critical_start + 0x80000000
.Lcritical_end:
.long __critical_end + 0x80000000
.Lcleanup_critical:
.long cleanup_critical
.section .rodata, "a"
#define SYSCALL(esa,esame,emu) .long esa
.globl sys_call_table
sys_call_table:
#include "syscalls.S"
#undef SYSCALL